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    FAO - livestock's long shadow FAO - livestock's long shadow Document Transcript

    • PrefaceThe in-depth assessment presented in this document of the various significant impactsof the world’s livestock sector on the environment is deliberately termed Livestock’s longshadow so as to help raise the attention of both the technical and the general public to thevery substantial contribution of animal agriculture to climate change and air pollution, toland, soil and water degradation and to the reduction of biodiversity. This is not done simplyto blame the rapidly growing and intensifying global livestock sector for severely damag-ing the environment but to encourage decisive measures at the technical and politicallevels for mitigating such damage. The detailed assessment of the various environmentalimpacts of the sector is therefore associated with the outline of technical and policy-related action to address these impacts. The assessment builds on the work of the Livestock, Environment and Development(LEAD) Initiative. This multi-stakeholder Initiative, coordinated by FAO’s Animal Productionand Health Division, was formed to address the environmental consequences of livestockproduction, particularly in the light of rising demand for food products of animal originand the increasing pressure on natural resources. The LEAD Initiative brought togethera broad range of research and development institutions and individuals interested inlivestock–environment interactions; it has been active in a number of areas of particularconcern, i.e. in land and water pollution from intensive livestock production in land degra-dation from overgrazing in dry lands and in livestock-induced deforestation in the humidand subhumid tropics. While previous assessments of the livestock–environment interactions by LEAD haveadopted a livestock sector perspective, i.e. investigated the impacts of the sector on thenatural resources used in animal production, the current assessment sets off from theenvironment and determines the contribution of livestock to changes to the environment(land use and climate change, soil, water and biodiversity depletion). The benefit of thischange in perspective is substantial in that it provides the framework for gauging the sig-nificant and dynamic role of the livestock sector in driving global environmental change.This in turn should assist and enhance decision-making on necessary action at all levels,from local to global, from private to public, from individual to corporate and from non-governmental to intergovernmental. Action is required: if, as predicted, the production ofmeat will double from now to 2050, we need to halve impacts per unit of output to achievea mere status quo in overall impact. LEAD has been catalysing such action, supported by the Global Environment Facility(GEF) and other donors, in a range of livestock-induced environmental “hotspots”, such asin East and Southeast Asia where solutions are designed for the sustainable managementof the very large quantities of livestock waste in intensive animal production, such as inCentral America where new procedures are introduced for the payment of environmentalservices in livestock-based land use, and such as in the United Republic of Tanzania where iii
    • sustainable wildlife–livestock interactions are designed. Such efforts require decisions on, and enforcement of, suitable policy instruments for enabling stakeholder engagement in economically sustainable resource use that addresses the environmental concerns at stake. It is obvious that the responsibility for the necessary action to address the environmental damage by the livestock sector goes far beyond the sector; it also goes beyond agriculture. While the sector, and agriculture as a whole, have to live up to the challenge of finding suitable technical solutions for more environmentally sustainable resource use in animal agriculture, the decisions concerning their use clearly transcend agriculture; multisector and multiobjective decision-making is required. It is hoped that this assessment contributes to such decision-making and to thus shrink “Livestock’s long shadow”. Samuel Jutzi Director Animal Production and Health Division FAOiv
    • ContentsAcknowledgements xviAbbreviations and acronyms xviiExecutive summary xxChapter 1Introduction 31.1 Livestock as a major player in global environmental issues 41.2 The setting: factors shaping the livestock sector 61.3 Trends within the livestock sector 14Chapter 2Livestock in geographic transition 232.1 Trends in livestock related land use 24 2.1.1 Overview: a regionally diverse pattern of change 24 2.1.2 Globalization drives national land-use change 27 2.1.3 Land degradation: a vast and costly loss 29 2.1.4 Livestock and land use: the “geographical transition” 312.2 Geography of demand 332.3 Geography of livestock resources 34 2.3.1 Pastures and fodder 34 2.3.2 Feedcrops and crop residues 38 2.3.3 Agro-industrial by-products 43 2.3.4 Future trends 452.4 Production systems: location economics at play 50 2.4.1 Historical trends and distribution patterns 51 2.4.2 Geographical concentration 57 2.4.3 Increasing reliance on transport 60 
    • 2.5 Hotspots of land degradation 63 2.5.1 Pastures and feedcrops still expanding into natural ecosystems 64 2.5.2 Rangeland degradation: desertification and vegetation changes 66 2.5.3 Contamination in peri-urban environments 68 2.5.4 Intensive feedcrop agriculture 70 2.6 Conclusions 74 Chapter 3 Livestock’s role in climate change and air pollution 79 3.1 Issues and trends 79 3.2 Livestock in the carbon cycle 84 3.2.1 Carbon emissions from feed production 86 3.2.2 Carbon emissions from livestock rearing 95 3.2.3 Carbon emissions from livestock processing and refrigerated transport 99 3.3 Livestock in the nitrogen cycle 101 3.3.1 Nitrogen emissions from feed-related fertilizer 104 3.3.2 Emissions from aquatic sources following chemical fertilizer use 105 3.3.3 Wasting of nitrogen in the livestock production chain 106 3.3.4 Nitrogen emissions from stored manure 107 3.3.5 Nitrogen emissions from applied or deposited manure 109 3.3.6 Emissions following manure nitrogen losses after application and direct deposition 111 3.4 Summary of livestock’s impact 112 3.5 Mitigation options 114 3.5.1 Sequestering carbon and mitigating CO2 emissions 115 3.5.2 Reducing CH4 emissions from enteric fermentation through improved efficiency and diets 119 3.5.3 Mitigating CH4 emissions through improved manure management and biogas 121 3.5.4 Technical options for mitigating N2O emissions and NH3 volatilization 122vi
    • Chapter 4Livestock’s role in water depletion and pollution 1254.1 Issues and trends 1254.2 Water use 128 4.2.1 Drinking and servicing 128 4.2.2 Product processing 130 4.2.3 Feed production 1334.3 Water pollution 135 4.3.1 Livestock waste 136 4.3.2 Wastes from livestock processing 149 4.3.3 Pollution from feed and fodder production 1534.4 Livestock land-use impacts on the water cycle 162 4.4.1 Extensive grazing alters water flows 162 4.4.2 Land-use conversion 1654.5 Summary of the impact of livestock on water 1674.6 Mitigation options 169 4.6.1 Improved water-use efficiency 169 4.6.2 Better waste management 171 4.6.3 Land management 176Chapter 5Livestock’s impact on biodiversity 1815.1 Issues and trends 1815.2 Dimensions of biodiversity 1835.3 Livestock’s role in biodiversity loss 187 5.3.1 Habitat change 187 5.3.2 Climate change 195 5.3.3 Invasive alien species 196 5.3.4 Overexploitation and competition 202 5.3.5 Pollution 2095.4 Summary of livestock impacts on biodiversity 2145.5 Mitigation options for conservation of biodiversity 215 vii
    • Chapter 6 Policy challenges and options 221 6.1 Towards a conducive policy framework 222 6.1.1 General principles 222 6.1.2 Specific policy instruments 229 6.1.3 Policy issues in climate change 237 6.1.4 Policy issues in water 241 6.1.5 Policy issues in biodiversity 249 6.2 Policies options for addressing environmental pressure points 256 6.2.1 Controlling expansion into natural ecosystems 256 6.2.2 Limiting rangeland degradation 259 6.2.3 Reducing nutrient loading in livestock concentration areas 261 6.2.4 Lessening the environmental impact of intensive feedcrop production 263 Chapter 7 Summary and conclusions 267 7.1 Livestock and environment in context 268 7.2 What needs to be done? 275 7.3 The challenge ahead 281 References 285 Annexes 1. Global maps 321 2. Tables 359 3. Methodology of quantification and analysis 377viii
    • Tables 1.1 Urbanization rates and growth rates 7 1.2 Changes in food consumption in developing countries 10 1.3 Use of feed concentrate 12 1.4 Key productivity parameters for livestock in different world regions 14 1.5 Past and projected trends in consumption of meat and milk in developing and developed countries 15 1.6 Developing country trends in livestock production in 2005 16 2.1 Regional trends in land use for arable land, pasture and forest from 1961 to 2001 26 2.2 Estimates of the global extent of land degradation 30 2.3 Estimates of all degraded land in dry areas 30 2.4 Livestock and total dietary protein supply in 1980 and 2002 34 2.5 Estimated remaining and converted grasslands 35 2.6 Land ownership and access rights on pastoral land, possible combinations and resulting level of access security for the livestock keeper 36 2.7 Land use and land ownership in the United States 37 2.8 Supply and recycling of food by-products in Japan 45 2.9 Global livestock population and production in different production systems 53 2.10 Livestock population and production in different production systems in developing countries 54 2.11 Livestock population and production in different agro-ecological zones 55 2.12 Trade as a share of total production for selected products 61 2.13 Contribution of livestock to soil erosion on agricultural lands in the United States in 2001 74 3.1 Past and current concentration of important greenhouse gases 82 ix
    • 3.2 Atmospheric carbon sources and sinks 85 3.3 Chemical fertilizer N used for feed and pastures in selected countries 87 3.4 CO2 emissions from fossil fuel burning to produce nitrogen fertilizer for feedcrops in selected countries 88 3.5 On-farm energy use for agriculture in Minnesota, United States 89 3.6 Livestock numbers (2002) and estimated carbon dioxide emissions from respiration 96 3.7 Global methane emissions from enteric fermentation in 2004 97 3.8 Global methane emissions from manure management in 2004 99 3.9 Indicative energy costs for processing 100 3.10 Energy use for processing agricultural products in Minnesota, United States, in 1995 101 3.11 Estimated total N2O emission from animal excreta 110 3.12 Role of livestock in carbon dioxide, methane and nitrous oxide emissions 113 3.13 Global terrestrial carbon sequestration potential from improved management 118 4.1 Water use and depletion by sector 126 4.2 Drinking-water requirements for livestock 129 4.3 Service water requirements for different livestock types 130 4.4 Water use for drinking-water requirements 131 4.5 Water use for service water requirements 132 4.6 Water use and depletion in tanning operations 133 4.7 Evapotranspiration of water for production of barley, maize, wheat and soybean (BMWS) for feed 136 4.8 Nutrient intake and excretions by different animals 137 4.9 Estimated relative contribution of pig waste, domestic wastewater and non-point sources to nitrogen emissions in water systems 139 4.10 Ranges of BOD concentration for various wastes and animal products 140
    • 4.11 Global N and P application on crops and pasture from chemical fertilizer and animal manure 147 4.12 Estimated N and P losses to freshwater ecosystems from manured agricultural lands 148 4.13 Heavy metal inputs to agricultural land in England and Wales in 2000 149 4.14 Typical waste water characteristics from animal processing industries 152 4.15 Pollution loads discharged in effluents from tanning operations 153 4.16 Mineral fertilizer consumption in different world regions between 1980 and 2000 154 4.17 Contribution of livestock production to agricultural N and P consumption in the form of mineral fertilizer in selected countries 155 4.18 Estimated N and P losses to freshwater ecosystems from mineral fertilizers consumed for feed and forage production 156 4.19 Livestock contribution to nitrogen and phosphorus discharges to surface waters from non-point source and point source pollution in the United States 157 4.20 Pesticide use for feed production in the United States 159 4.21 Seasonal effects of vegetation composition change on water yield, by climate type 166 4.22 Estimated contribution of the livestock sector to water use and depletion processes 168 5.1 Estimated numbers of described species and possible global total 183 5.2 Major ecosystems and threats 186 5.3 Expert ranking of livestock-related threats to biodiversity resulting from the different mechanisms and types of production system 216 6.1 Comparison of key technical parameters in the beef industry in the Amazon area of Brazil (1985–2003) 256 7.1 Global facts about livestock 271 xi
    • Figures 1.1 Past and projected global rural and urban populations from 1950 to 2030 7 1.2 Consumption function of animal products at different levels of urbanization in China 8 1.3 Past and projected GDP per capita growth by region 8 1.4 The relationship between meat consumption and per capita income in 2002 9 1.5 Past and projected food consumption of livestock products 10 1.6 Past and projected meat production in developed and developing countries from 1970 to 2050 15 1.7 Past and projected milk production in developed and developing countries from 1970 to 2050 15 2.1 Estimated changes in land use from 1700 to 1995 24 2.2 Total harvested area and total production for cereals and soybeans 27 2.3 Comparative growth rates for production of selected animal products and feed grain use in developing countries 39 2.4 Regional trends in the use of feed grains 39 2.5 Feed demand for maize and wheat in selected regions and countries from 1961 to 2002 40 2.6 Relative composition of chicken feed ration in selected countries (by weight) 41 2.7 Relative composition of pig feed basket in selected countries (by weight) 42 2.8 Global trends in demand for soybean and soybean cake from 1961 to 2002 44 2.9 Classification of livestock production systems 52 2.10 Comparative distribution of pig and poultry 56xii
    • 2.11 Changes in geographical concentration of hens in Brazil from 1992 to 2001 57 2.12 Changes in geographical concentration of pigs in Brazil from 1992 to 2001 57 2.13 Changes in geographical concentration of pigs in France from 1989 to 2001 58 2.14 Changes in the peri-urban concentration of poultry from 1992 to 2000 in Thailand 59 2.15 Changes in geographical concentration of cattle in Brazil from 1992 to 2001 60 2.16 Ecological footprint per person, by component 65 2.17 Spatial distribution of humans, livestock and feed crops around Bangkok, 2001 70 2.18 Global trends in land-use area for livestock and total production of meat and milk 75 2.19 Trends in land-use area for livestock and local supply of meat and milk – EU-15 76 2.20 Trends in land-use area for livestock and local supply of meat and milk – South America 76 2.21 Trends in land-use area for livestock and local supply of meat and milk – East and Southeast Asia (excluding China) 76 3.1 The present carbon cycle 84 3.2 The nitrogen cycle 102 3.3 Spatial pattern of total inorganic nitrogen deposition in the early 1990s 115 4.1 Flow diagram for meat processing operations 133 4.2 Process of stream degradation caused by grazing 165 4.3 Technical options in manure management 174 6.1 Shift in livestock policy objectives in relation to economic development 226 6.2 General principles for pricing water 243 xiii
    • Boxes 2.1 Recent trends in forestry expansion 25 2.2 The complex and weakening control of access to pastureland 36 2.3 Ecological footprint 65 2.4 Livestock waste management in East Asia 71 2.5 Livestock production systems and erosion in the United States 73 3.1 The Kyoto Protocol 81 3.2 The many climatic faces of the burning of tropical savannah 94 3.3 A new assessment of nitrous oxide emissions from manure by production system, species and region 110 4.1 Livestock water use in Botswana 131 4.2 Impact of livestock intensification on nutrient balance in Asia 150 4.3 Pesticide use for feed production in the United States 158 5.1 The case of the protected areas 190 5.2 Changes in the Cerrado, Brazil’s tropical savannah 192 5.3 Woody encroachment in southern Texas 194 5.4 Wild birds and highly pathogenic avian influenza 198 5.5 From pampas to cardoon, to alfalfa, to soy 201 5.6 Gulf of Mexico hypoxia 212 5.7 Livestock production to safeguard wildlife 218 6.1 New Zealand–environmental impact of major agricultural policy reforms 232 6.2 Payment for environmental services in Central America 258 6.3 Wildlife management areas and land-use planning in the United Republic of Tanzania 260 6.4 Examples of successful management of livestock waste production from intensive agriculture 264xiv
    • Maps 2.1 Location of industrial pig sector in southern Viet Nam (Dong Nai, Binh Duong, Ho Chi Minh city and Long An province) 58 4.1 Estimated contribution of livestock to total P2O5 supply on agricultural land, in an area presenting a P2O5 mass balance of more than 10 kg per hectare. Selected Asian countries – 1998 to 2000. 151 4.2 Risk of human-induced water erosion 161 5.1 Major flyways of migratory birds (Shore birds) 198 5.2 Feed production in the Mississippi River drainage basin and general location of the 1999 midsummer hypoxic zone 212 xv
    • Acknowledgements This assessment of global livestock–environment interactions was called for by the Steer- ing Committee of the Livestock, Environment and Development (LEAD) Initiative at its meeting in May 2005 in Copenhagen. The assessment was conducted by the members of the LEAD team at FAO and the chair of LEAD. This assessment would not have been possible without the financial support and guid- ance from the LEAD Steering Committee, including Hanne Carus, Jorgen Henriksen and Jorgen Madsen (Denmark), Andreas Gerrits and Fritz Schneider (Switzerland), Philippe Chedanne, Jean-Luc François and Laurent Bonneau (France), Annette von Lossau (Germa- ny), Luis Cardoso (Portugal), Peter Bazeley (United Kingdom), Joyce Turk (United States), Ibrahim Muhammad (Tropical Agricultural Research and Higher Education Center, CATIE), Emmanuel Camus (Centre de coopération internationale en recherche agronomique pour le développement, CIRAD), Philippe Steinmetz and Philippe Vialatte (European Union), Samuel Jutzi (Food and Agriculture Organization, FAO), Ahmed Sidahmed (then International Fund for Agriculture, IFAD), Carlos Seré and Shirley Tarawali (International Livestock Research Institute, ILRI), Deborah Bossio (International Water Management Institute, IWMI), Carlos Pomerada (Costa Rica), Modibo Traoré (African Union/Inter-Afri- can Bureau for Animal Resources, AU/IBAR), Bingsheng Ke (Research Center for Rural Economy – Ministry of Agriculture, China) and Paul Ndiaye (Université Cheikh Anta-Diop, Senegal). Our sincere thanks go to those who kindly agreed to review various drafts includ- ing Wally Falcon and Hal Mooney (Stanford University, United States), Samuel Jutzi and Freddie Nachtergaele (FAO), Harald Menzi and Fritz Schneider (Swiss College of Agri- culture), Andreas Gerrits (Swiss Agency for Development and Cooperation, SDC), Jorgen Henriksen (Denmark) and Günter Fischer (International Institute for Applied Systems Analysis, IIASA), José Martinez (Institut de recherche pour l’ingéniere de l’agriculture et de l’environnement, CEMAGREF), Jim Galloway (University of Virginia) and Padma Kumar (Capitalisation of Livestock Programme Experiences in India, CALPI). From within FAO, comments were received from Jelle Bruinsma, Neela Gangadharan, Wulf Killmann and Jan Poulisse. Our thanks also go to Wally Falcon, Hal Mooney and Roz Naylor (Stanford University) for providing a stimulating working environment and continuous debate and encouragement. We also wish to acknowledge the support of Paul Harrison for style editing; Rosemary Allison for copyediting; Sébastien Pesseat and Claudia Ciarlantini for graphic design; Carolyn Opio, Jan Groenewold and Tom Misselbrook for support in data analysis; Ales- sandra Falcucci for support in spatial analysis and mapping and Christine Ellefson for a variety of support tasks. No need to say that all remaining errors and omissions remain the sole responsibility of the authors.xvi
    • Abbreviations and acronymsA/R Afforestation or reforestationAET Actual evapotranspirationASA American Soybean AssociationAU-IBAR African Union – Inter-African Bureau for Animal ResourcesBMWS Barley, maize, wheat and soybeanBNF Biological nitrogen fixationBOD Biological oxygen demandBSE Bovine spongiform encephalopathyCALPI Capitalisation of Livestock Programme Experiences in IndiaCAP Common Agricultural PolicyCATIE Tropical Agricultural Research and Higher Education CentreCBD Convention on Biological DiversityCDM Clean development mechanismCEMAGREF Recherche et expertise sur la multifonctionnalité de l’agricultureCERs Certified emissions reductionsCIRAD Centre de coopération en recherche agronomique pour le développementCIS Commonwealth of Independent StatesCOD Chemical oxygen demandCSA Central and South AmericaDANIDA Danish International Development AgencyEmbrapa Empresa Brasileira de Pesquisa Agropecuária – Ministério da Agricoltura, Pecuària e AbastecimentoEU European UnionFAO Food and Agriculture Organization of the United NationsFAOSTAT FAO statistical databasesFRA Global Forest Resource AssessmentGATT General Agreement on Tariffs and TradeGDP Gross domestic productGEF Global Environmental FacilityGHG Greenhouse gasesGMO Genetically modified organisms xvii
    • GWP Global warming potential HPAI Highly pathogenic avian influenza IFA International Fertilizer Industry Association IFAD International Fund for Agricultural Development IFPRI International Food Policy Research Institute IIASA Institute for Applied Systems Analysis IOM Institute of Medicine IPCC Intergovernmental Panel on Climate Change IUCN The World Conservation Union (formerly the International Union for the Conservation of Nature and Natural Resources) IWMI International Water Management Institute LEAD Livestock, Environment and Development (Initiative) LPS Livestock production system LULUCF Land use, land-use change and forestry LWMEAP Livestock Waste Management in East Asia Project MAFF–­UK Ministry of Agriculture, Fisheries and Food, United Kingdom of Great Britain and Northern Ireland MAF–­NZ Ministry of Agriculture and Forestry – New Zealand MEA Millennium Ecosystem Assessment NASA National Aeronautics and Space Administration NEC National Emission Ceiling (directive) NOAA National Oceanic and Atmospheric Administration OECD Organisation for Economic Co-operation and Development OIE World Organization for Animal Health PES Payment for environmental services ppb Parts per billion ppm Parts per million RCRE Rutgers Cooperative research and extension SAfMA South African Millennium Ecosystem Assessment SCOPE Scientific Committee on Problems of the Environment SOC Soil organic carbon SSA Sub-Saharan Africa TOC Total organic carbon UNCCD United Nations Convention to Combat Desertification in those Countries Experiencing Serious Drought and/or Desertification, particularly in Africa. UNCED United Nations Conference on Environment and Development UNDP United Nations Development Programmexviii
    • UNEP United Nations Environment ProgrammeUNEP‑WCMC UNEP World Conservation Monitoring CentreUNESCO United Nations Educational, Scientific and Cultural OrganizationUNFCCC United Nations Framework Convention on Climate ChangeUSDA/FAS United States Department of Agriculture: Foreign Agricultural ServiceUSDA-NRCS United States Department of Agriculture–­National Resources Conservation ServiceUSEPA United States Environmental Protection AgencyWANA West Asia and North AfricaWHO World Health OrganizationWMAs Wildlife Management AreasWRI World Resources InstituteWTO World Trade OrganizationWWF World Wide Fund for Nature xix
    • Executive summary This report aims to assess the full impact of the livestock sector on environmental prob- lems, along with potential technical and policy approaches to mitigation. The assess- ment is based on the most recent and complete data available, taking into account direct impacts, along with the impacts of feedcrop agriculture required for livestock production. The livestock sector emerges as one of the top two or three most significant contribu- tors to the most serious environmental problems, at every scale from local to global. The findings of this report suggest that it should be a major policy focus when dealing with problems of land degradation, climate change and air pollution, water shortage and water pollution and loss of biodiversity. Livestock’s contribution to environmental problems is on a massive scale and its poten- tial contribution to their solution is equally large. The impact is so significant that it needs to be addressed with urgency. Major reductions in impact could be achieved at reasonable cost. Global importance of the sector Although economically not a major global player, the livestock sector is socially and politically very significant. It accounts for 40 percent of agricultural gross domestic product (GDP). It employs 1.3 billion people and creates livelihoods for one billion of the world’s poor. Livestock products provide one-third of humanity’s protein intake, and are a contrib- uting cause of obesity and a potential remedy for undernourishment. Growing populations and incomes, along with changing food preferences, are rapidly increasing demand for livestock products, while globalization is boosting trade in livestock inputs and products. Global production of meat is projected to more than double from 229 million tonnes in 1999/01 to 465 million tonnes in 2050, and that of milk to grow from 580 to 1 043 million tonnes. The environmental impact per unit of livestock production must be cut by half, just to avoid increasing the level of damage beyond its present level. Structural changes and their impact The livestock sector is undergoing a complex process of technical and geographical change, which is shifting the balance of environmental problems caused by the sector. Extensive grazing still occupies and degrades vast areas of land; though there is an increasing trend towards intensification and industrialization. Livestock production is shifting geographically, first from rural areas to urban and peri-urban, to get closer to consumers, then towards the sources of feedstuff, whether these are feedcrop areas, or transport and trade hubs where feed is imported. There is also a shift of species, with production of monogastric species (pigs and poultry, mostly produced in industrial units) growing rapidly, while the growth of ruminant production (cattle, sheep and goats, oftenxx
    • raised extensively) slows. Through these shifts, the livestock sector enters into more anddirect competition for scarce land, water and other natural resources. These changes are pushing towards improved efficiency, thus reducing the land arearequired for livestock production. At the same time, they are marginalizing smallholdersand pastoralists, increasing inputs and wastes and increasing and concentrating the pol-lution created. Widely dispersed non-point sources of pollution are ceding importance topoint sources that create more local damage but are more easily regulated.Land degradationThe livestock sector is by far the single largest anthropogenic user of land. The total areaoccupied by grazing is equivalent to 26 percent of the ice-free terrestrial surface of theplanet. In addition, the total area dedicated to feedcrop production amounts to 33 percentof total arable land. In all, livestock production accounts for 70 percent of all agriculturalland and 30 percent of the land surface of the planet. Expansion of livestock production is a key factor in deforestation, especially in LatinAmerica where the greatest amount of deforestation is occurring – 70 percent of previousforested land in the Amazon is occupied by pastures, and feedcrops cover a large part ofthe remainder. About 20 percent of the world’s pastures and rangelands, with 73 percent ofrangelands in dry areas, have been degraded to some extent, mostly through overgrazing,compaction and erosion created by livestock action. The dry lands in particular are affectedby these trends, as livestock are often the only source of livelihoods for the people livingin these areas. Overgrazing can be reduced by grazing fees and by removing obstacles to mobility oncommon property pastures. Land degradation can be limited and reversed through soilconservation methods, silvopastoralism, better management of grazing systems, limits touncontrolled burning by pastoralists and controlled exclusion from sensitive areas.Atmosphere and climateWith rising temperatures, rising sea levels, melting icecaps and glaciers, shifting oceancurrents and weather patterns, climate change is the most serious challenge facing thehuman race. The livestock sector is a major player, responsible for 18 percent of greenhouse gasemissions measured in CO2 equivalent. This is a higher share than transport. The livestock sector accounts for 9 percent of anthropogenic CO2 emissions. The largestshare of this derives from land-use changes – especially deforestation – caused by expan-sion of pastures and arable land for feedcrops. Livestock are responsible for much largershares of some gases with far higher potential to warm the atmosphere. The sector emits37 percent of anthropogenic methane (with 23 times the global warming potential (GWP) ofCO2) most of that from enteric fermentation by ruminants. It emits 65 percent of anthropo-genic nitrous oxide (with 296 times the GWP of CO2), the great majority from manure. Live-stock are also responsible for almost two-thirds (64 percent) of anthropogenic ammoniaemissions, which contribute significantly to acid rain and acidification of ecosystems. This high level of emissions opens up large opportunities for climate change mitiga-tion through livestock actions. Intensification – in terms of increased productivity both in xxi
    • livestock production and in feedcrop agriculture – can reduce greenhouse gas emissions from deforestation and pasture degradation. In addition, restoring historical losses of soil carbon through conservation tillage, cover crops, agroforestry and other measures could sequester up to 1.3 tonnes of carbon per hectare per year, with additional amounts available through restoration of desertified pastures. Methane emissions can be reduced through improved diets to reduce enteric fermentation, improved manure management and biogas – which also provide renewable energy. Nitrogen emissions can be reduced through improved diets and manure management. The Kyoto Protocol’s clean development mechanism (CDM) can be used to finance the spread of biogas and silvopastoral initiatives involving afforestation and reforestation. Methodologies should be developed so that the CDM can finance other livestock-related options such as soil carbon sequestration through rehabilitation of degraded pastures. Water The world is moving towards increasing problems of freshwater shortage, scarcity and depletion, with 64 percent of the world’s population expected to live in water-stressed basins by 2025. The livestock sector is a key player in increasing water use, accounting for over 8 percent of global human water use, mostly for the irrigation of feedcrops. It is probably the largest sectoral source of water pollution, contributing to eutrophication, “dead” zones in coastal areas, degradation of coral reefs, human health problems, emergence of antibiotic resist- ance and many others. The major sources of pollution are from animal wastes, antibiotics and hormones, chemicals from tanneries, fertilizers and pesticides used for feedcrops, and sediments from eroded pastures. Global figures are not available but in the United States, with the world’s fourth largest land area, livestock are responsible for an estimated 55 percent of erosion and sediment, 37 percent of pesticide use, 50 percent of antibiotic use, and a third of the loads of nitrogen and phosphorus into freshwater resources. Livestock also affect the replenishment of freshwater by compacting soil, reducing infil- tration, degrading the banks of watercourses, drying up floodplains and lowering water tables. Livestock’s contribution to deforestation also increases runoff and reduces dry season flows. Water use can be reduced through improving the efficiency of irrigation systems. Livestock’s impact on erosion, sedimentation and water regulation can be addressed by measures against land degradation. Pollution can be tackled through better management of animal waste in industrial production units, better diets to improve nutrient absorption, improved manure management (including biogas) and better use of processed manure on croplands. Industrial livestock production should be decentralized to accessible croplands where wastes can be recycled without overloading soils and freshwater. Policy measures that would help in reducing water use and pollution include full cost pricing of water (to cover supply costs, as well as economic and environmental externali- ties), regulatory frameworks for limiting inputs and scale, specifying required equipment and discharge levels, zoning regulations and taxes to discourage large-scale concentra- tions close to cities, as well as the development of secure water rights and water markets, and participatory management of watersheds.xxii
    • BiodiversityWe are in an era of unprecedented threats to biodiversity. The loss of species is estimatedto be running 50 to 500 times higher than background rates found in the fossil record. Fif-teen out of 24 important ecosystem services are assessed to be in decline. Livestock now account for about 20 percent of the total terrestrial animal biomass, andthe 30 percent of the earth’s land surface that they now pre-empt was once habitat forwildlife. Indeed, the livestock sector may well be the leading player in the reduction ofbiodiversity, since it is the major driver of deforestation, as well as one of the leading driv-ers of land degradation, pollution, climate change, overfishing, sedimentation of coastalareas and facilitation of invasions by alien species. In addition, resource conflicts withpastoralists threaten species of wild predators and also protected areas close to pastures.Meanwhile in developed regions, especially Europe, pastures had become a location ofdiverse long-established types of ecosystem, many of which are now threatened by pastureabandonment. Some 306 of the 825 terrestrial ecoregions identified by the Worldwide Fund for Nature(WWF) – ranged across all biomes and all biogeographical realms, reported livestock asone of the current threats. Conservation International has identified 35 global hotspots forbiodiversity, characterized by exceptional levels of plant endemism and serious levels ofhabitat loss. Of these, 23 are reported to be affected by livestock production. An analysis ofthe authoritative World Conservation Union (IUCN) Red List of Threatened Species showsthat most of the world’s threatened species are suffering habitat loss where livestock area factor. Since many of livestock’s threats to biodiversity arise from their impact on the mainresource sectors (climate, air and water pollution, land degradation and deforestation),major options for mitigation are detailed in those sections. There is also scope for improv-ing pastoralists’ interactions with wildlife and parks and raising wildlife species in live-stock enterprises. Reduction of the wildlife area pre-empted by livestock can be achieved by intensification.Protection of wild areas, buffer zones, conservation easements, tax credits and penaltiescan increase the amount of land where biodiversity conservation is prioritized. Effortsshould extend more widely to integrate livestock production and producers into landscapemanagement.Cross-cutting policy frameworksCertain general policy approaches cut across all the above fields. A general conclusion isthat improving the resource use efficiency of livestock production can reduce environmen-tal impacts. While regulating about scale, inputs, wastes and so on can help, a crucial element inachieving greater efficiency is the correct pricing of natural resources such as land, waterand use of waste sinks. Most frequently natural resources are free or underpriced, whichleads to overexploitation and pollution. Often perverse subsidies directly encourage live-stock producers to engage in environmentally damaging activities. A top priority is to achieve prices and fees that reflect the full economic and environmen-tal costs, including all externalities. One requirement for prices to influence behaviour is xxiii
    • that there should be secure and if possible tradable rights to water, land, use of common land and waste sinks. Damaging subsidies should be removed, and economic and environmental externalities should be built into prices by selective taxing of and/or fees for resource use, inputs and wastes. In some cases direct incentives may be needed. Payment for environmental services is an important framework, especially in relation to extensive grazing systems: herders, producers and landowners can be paid for specific environmental services such as regulation of water flows, soil conservation, conservation of natural landscape and wildlife habitats, or carbon sequestration. Provision of environ- mental services may emerge as a major purpose of extensive grassland-based production systems. An important general lesson is that the livestock sector has such deep and wide-ranging environmental impacts that it should rank as one of the leading focuses for environmental policy: efforts here can produce large and multiple payoffs. Indeed, as societies develop, it is likely that environmental considerations, along with human health issues, will become the dominant policy considerations for the sector. Finally, there is an urgent need to develop suitable institutional and policy frameworks, at local, national and international levels, for the suggested changes to occur. This will require strong political commitment, and increased knowledge and awareness of the environmental risks of continuing “business as usual” and the environmental benefits of actions in the livestock sector.xxiv
    • 01
    • IntroductionL ivestock activities have significant impact on virtually all aspects of the environment,including air and climate change, land and soil, input production prevails, mainly for subsist- ence rather than for commercial purposes. This contrasts with commercial, high-input produc-water and biodiversity. The impact may be direct, tion in areas serving a growing or establishedthrough grazing for example, or indirect, such high demand. Such diverse production systemsas the expansion of soybean production for feed make extremely diverse claims on resources.replacing forests in South America. The diversity of production systems and interac- Livestock’s impact on the environment tions makes the analysis of the livestock–envi-is already huge, and it is growing and rap- ronment interface complex and sometimes con-idly changing. Global demand for meat, milk and troversial.eggs is fast increasing, driven by rising incomes, The livestock sector affects a vast range of nat-growing populations and urbanization. ural resources, and must be carefully managed As an economic activity, livestock production given the increasing scarcity of these resourcesis technically extremely diverse. In countries or and the opportunities that they represent forareas where there is no strong demand for food other sectors and activities. While intensiveproducts of animal origin, subsistence and low- livestock production is booming in large emerg-
    • Livestock’s long shadowing countries, there are still vast areas where environmental requirement, and a social andextensive livestock production and its associated health necessity. Animal foods are susceptiblelivelihoods persist. Both intensive and extensive to pathogens and often carry chemical residues.production requires attention and intervention so Food safety requirements must be met, and arethat the livestock sector can have fewer negative generally a prerequisite in formal markets.and more positive impacts on national and global The previous assessments of the Livestockpublic goods. Environment and Development (LEAD) Initiative A major motivation for this assessment is (de Haan, Steinfeld and Blackburn, 1997; Stein-that the environmental issues linked to livestock feld, de Haan and Blackburn, 1997) emphasizedhave not generally received an adequate insti- the livestock sector perspective and analysedtutional response – neither in developing nor in livestock‑environment interactions from thedeveloped countries. Livestock sector growth perspective of a livestock production system.in some places, and stagnation with poverty in This updated assessment inverts this approachothers, go largely uncontrolled. Although usually and starts from an environmental perspective. Itconsidered part of agriculture, in many places attempts to provide an objective assessment oflivestock production has grown in the same way the many diverse livestock–environment interac-as industry, and is no longer directly tied to land tions. Economic, social and public health objec-or to specific locations. tives are of course taken into account so as to As the environment around the animals is reach realistic conclusions. This assessmentincreasingly modified and standardized, environ- then outlines a series of potential solutions thatmental impacts swiftly change. Public policies, in can effectively address the negative consequenc-developed and developing countries alike, barely es of livestock production.keep pace with rapid transformations in produc-tion technology and structural shifts in the sec- 1.1 Livestock as a major player intor. Environmental laws and programmes are global environmental issuesusually put in place only after significant damage Livestock have a substantial impact on thehas already occurred. The focus continues to world’s water, land and biodiversity resourcesbe placed on protection and restoration, rather and contribute significantly to climate change.than on the more cost-effective approaches of Directly and indirectly, through grazing andprevention and mitigation. through feedcrop production, the livestock sec- In the varied contexts of the livestock sec- tor occupies about 30 percent of the ice-freetor, environmental issues require an integrated terrestrial surface on the planet. In many situ-approach, combining policy measures and tech- ations, livestock are a major source of land-nology changes, within a framework of multiple based pollution, emitting nutrients and organicobjectives. matter, pathogens and drug residues into riv- The livelihood concerns of hundreds of mil- ers, lakes and coastal seas. Animals and theirlions of poor livestock holders, who often engage wastes emit gases, some of which contribute toin livestock production because they have no climate change, as do land-use changes causedalternative, must be taken into account. The by demand for feedgrains and grazing land.demands of the emerging middle class, who are Livestock shape entire landscapes and theirconsuming growing amounts of meat, milk and demands on land for pasture and feedcrop pro-eggs, cannot be ignored either. Attempts to curb duction modify and reduce natural habitats.the booming demand for these products have Using animals for food and other products andgenerally proved ineffective. services is only one of many human activities Better policies in the livestock sector are an that depend on natural resources. Humans are
    • Introductionusing the world’s renewable natural resources may greatly increase the number of hungry peo-at rates that increasingly exceed their natu- ple, most severely in sub-Saharan Africa (FAO,ral abilities to renew themselves (Westing, Fox 2005a). According to FAO, developing countriesand Renner, 2001). Humans introduce growing may lose about 280 million tonnes of potentialamounts of pollutants into the air, water and cereal production as a result of climate change.soil, at rates ever higher than the capacity of the Because of habitat losses, unsustainable formsenvironment to dissipate or decompose these of exploitation and climate change, the loss ofpollutants. Humans are encroaching on what biodiversity continues to accelerate. The Mil-remains of relatively undisturbed environments, lennium Ecosystem Assessment (MEA, 2005a),putting biodiversity at risk of mass extinction. in a comprehensive assessment of the envi-Anthropogenic land-use changes have acceler- ronmental health of the planet, estimates thatated over the last decades, most dramatically in species are disappearing at 100 to 1 000 timesdeveloping countries. Urbanization and expan- the background levels seen in fossil records. Thesion of cropping have led to an unprecedented MEA gauged that one-third of all amphibians, aloss and fragmentation of habitats, including fifth of mammals and an eighth of all birds arevaluable ones such as forests and wetlands. now threatened by extinction. This assessment is Water availability is becoming a serious con- based on known species and it is estimated thatstraint to the expansion of agriculture and to 90 percent or more of all existing species havemeeting other growing human needs. Agricul- not been catalogued yet. While some speciesture is the largest user of water, accounting for provide obvious services such as food, timber or70 percent of total freshwater use. clothing, most species’ services are more diffi- While there are different views on the extent of cult to see and, therefore, less appreciated. Theyclimate change and its effect on the environment, include recycling of nutrients, pollination andit is now firmly established that anthropogenic seed dispersal, climate control and purificationclimate change is indeed occurring. The most of air and water.important gas associated with climate change Additional land available for cultivation is lim-is carbon dioxide (CO2) while other greenhouse ited. Therefore, most of the increase in agricul-gases, including methane, nitrous oxide, ozone tural production has come, and will come, fromand sulphur hexafluoride also contribute. Car- intensification of land that is already cropped orbon dioxide levels have increased by over 40 per- grazed. As a large user of crops and other plantcent over the past 200 years, from 270 parts per material, the livestock sector must continue tomillion (ppm) to 382 ppm (NOAA, 2006). Today, improve the conversion of these materials intoCO2 concentrations are higher than at any time edible products.during the last 650 000 years (Siegenthaler et al., The overall impact of livestock activities on the2005). Methane concentrations today are more environment is enormous. Part of the damagethan twice the pre-industrial level (Spahni et al., can be offset by applying scientific knowledge2005). Average temperatures have increased by and technological capability for dealing with0.8°C over the past century (NASA, 2005). Com- these problems. Meanwhile, the vast legacy ofbustion of fossil fuels is a major contributor to damage leaves future generations with a debt.these changes. Ultimately, environmental issues are social Climate change means an increase in average issues: environmental costs created by sometemperature and seems to be associated with an groups and nations are carried by others, or byincreased frequency of extreme weather events. the planet as a whole. The health of the environ-FAO warns that food distribution systems and ment and the availability of resources affect thetheir infrastructure will be disrupted, and this welfare of future generations, and overuse of 
    • Livestock’s long shadowresources and excess environmental pollution by or bilharzia, carried by water snails, is associatedcurrent generations are to their detriment. with changing water flows. The World Resources Environmental degradation is often associated Report (1999) underlines how the burden ofwith war and other forms of conflict. Throughout these preventable and environment-related dis-history, peoples and nations have fought over eases is borne disproportionately by the poor,natural resources such as land and water. By both in developing and developed countries.increasing the scarcity of these resources, envi- Environmental degradation at its current scaleronmental degradation increases the likelihood and pace is clearly a serious threat for the sus-of violent conflict, particularly when there is a tainability of natural resources. The functioninglack of governing institutions. In recent years, of ecosystems, both at local and global levels,public attention has been drawn to the prospect is already seriously compromised. Ultimately, ifthat future wars will be fought over increas- left unchecked, environmental degradation mayingly scarce natural resources (see, for example, threaten not only economic growth and stabilityKlare, 2001, or Renner, 2002). A Pentagon report but the very survival of humans on the planet.(Schwartz and Randall, 2003) suggested thatglobal warming could prove a greater risk to 1.2 The setting: factors shaping thethe world than terrorism and could lead to cata- livestock sectorstrophic droughts, famines and riots. The livestock sector, along with food and agri- At the local or regional level, the South- culture in general, is undergoing far-reachingern African Millennium Ecosystem Assessment change, much of it driven by factors outside the(SAfMA) (Biggs et al., 2004) reveals a striking sector. Growing populations and other demo-connection between ecological stress and social graphic factors such as age structure and urban-conflict. This SAfMA study suggests causal links ization determine food demand and have drivenin both directions; conflict may cause environ- the intensification of agriculture for centuries.mental degradation but the latter may also trig- Growing economies and individual incomes haveger conflict. The study quotes political violence also contributed to growing demand and a shiftin South Africa’s KwaZulu Natal Province as an in diets. These trends have accelerated over theexample where faction fighting over scarce land last two decades in large parts of Asia, Latinfor cattle has led to a series of killings. Water America and the Near East, spurring a rapidscarcity, land degradation from overgrazing or increase in demand for animal products andwoodfuel shortages can also lead to conflict. other high value foodstuffs such as fish, vegeta-The same study points to Burundi, Rwanda and bles and oils.eastern Congo as areas where major ecologi- The agriculture sector has responded to thecal problems have marched hand in hand with increased and diversified demands for foodrecent histories of violent conflict. items with innovations in biology, chemistry and Environmental degradation significantly affects machinery. It has done so mainly through inten-human health, both directly and indirectly. Direct sification rather than expansion. Land use haseffects on human health include contact with changed correspondingly.pollutants. Indirect effects include increased These secular changes of population, econ-exposure of humans and of animals to infec- omies, diets, technology and land use drivetious diseases because of climate change. The changes in the global livestock sector while,geographic range and seasonality of a number to some extent, the sector itself shapes theseof important diseases, including malaria and forces. Sketching these broad developmentsdengue fever, are very sensitive to changes in cli- helps to understand the context within which thematic conditions (UNEP 2005a). Schistosomiasis livestock sector operates.
    • IntroductionThe demographic transition Table 1.1Growing populations and cities boost and Urbanization rates and urbanization growth rateschange food demand Region Urban population Urbanization as percent of growth rate Population and population growth are major total population (Percentage determinants of the demand for food and other in 2005 per annum agricultural products. World population is cur- 1991–2005)rently 6.5 billion, growing at the rate of 76 million South Asia 29 2.8annually (UN, 2005). The UN’s medium projec- East Asia and the Pacific 57 2.4tion forecasts that world population will reach Sub-Saharan Africa 37 4.49.1 billion by 2050, peaking at around 9.5 billion West Asia and North Africa 59 2.8by the year 2070 (UN, 2005). Latin America and the Caribbean 78 2.1 While populations in the developed countries Developing countries 57 3.1as a whole are close to stagnant, 95 percent of Developed countries 73 0.6the population increase is occurring in devel- World 49 2.2oping countries. The fastest population growth Source: FAO (2006a) and FAO (2006b).rates (averaging 2.4 percent annually) are occur-ring in the group of 50 least developed countries(UN, 2005). Population growth rates are slowing world, with growth rates highest where currentbecause of decreased fertility rates, and are urbanization is low, particularly in South Asiabelow replacement levels in most developed and sub-Saharan Africa. Virtually all populationcountries and decreasing rapidly in emerging growth between 2000 and 2030 will be urbancountries, although they remain high in least (FAO, 2003a) (see Figure 1.1).developed countries. Urbanization usually implies higher levels of Fertility decline, in conjunction with increases participation in the workforce and has an impactin life expectancy, is leading to population ageing on patterns of food consumption, In cities, peo-globally. The proportion of older people (aged ple typically consume more food away from60 and over) is projected to double to more than home, and consume higher amounts of pre-20 percent from today’s level (UN, 2005). Age cooked, fast and convenience foods, and snacksgroups differ in their dietary and consumptionpatterns, with adults and older people typicallyconsuming larger amounts of animal protein Figure 1.1 Past and projected global rural and than children. urban populations from 1950 to 2030 Another important factor determining demandfor food is urbanization. In 2005 (the latest year 6 projectionsfor which statistics are available) 49 percent of 5the world population were living in cities (FAO, Billion people 42006b). This global figure masks important dif- 3ferences among the world regions: sub-Saharan 2Africa and South Asia are still only moderately 1urbanized – with 37 and 29 percent urbanization, 0respectively – whereas urbanization rates are 1950 1960 1970 1980 1990 2000 2010 2020 2030around 70 to 80 percent in developed countries Rural Urbanand in Latin America (FAO, 2006a; 2006b) (seeTable 1.1). Source: FAO (2006a) and FAO (2006b). Urbanization continues in all regions of the 
    • Livestock’s long shadow Figure 1.2 Consumption function of animal products at different levels of urbanization in China 500© FAO/Swa13B_0063/G. Bizzarri consumption (kcalories/person/day) 450 400 350 300 250 200 A student orders fast food near Luve – Swaziland 150 100 400 600 800 1 000 1 200 real PCE/person (1980 US$ppp) (Schmidhuber and Shetty, 2005; Rae, 1998; King, U=30% U=25% U=20% Tietyen and Vickner, 2000). Therefore, urbaniza- tion influences the position and the shape of Note: PCE: per capita expenditure. U = percent urban. PPP: the consumption functions for animal products purchasing power parity. (Rae, 1998) – this function measures the way in Source: Rae (1998). which consumption of a given item responds to changes in total expenditure. For China, a given increase in urbanization has China and 45 percent in urban areas. Meanwhile, a positive effect on per capita consumption lev- meat and egg consumption increased by 85 per- els of animal products (Rae, 1998) (Figure 1.2). cent and 278 percent respectively in rural areas Between 1981 and 2001, human consumption and by 29 percent and 113 percent in urban areas of grains dropped by 7 percent in rural areas of (Zhou, Wu and Tian, 2003). Figure 1.3 Past and projected GDP per capita growth by region 8.00 7.00 6.00 Percentage per annum 5.00 4.00 3.00 2.00 1.00 0.00 -1.00 -2.00 East Asia South Asia Sub-Saharan Middle East Latin OECD Transition Developed Developing and the Africa and America economies economies Pacific North Africa and the Caribbean 1991–2003 2003–2015 2015–2030 Source: World Bank (2006) and FAO (2006a). 
    • IntroductionEconomic growth percent, led by China, followed by South AsiaGrowing incomes boost demand for livestock with 3.6 percent. The World Bank (2006) projectsproducts that GDP growth in developing countries willOver recent decades, the global economy has accelerate in coming decades (Figure 1.3).experienced an unparalleled expansion. Popula- There is a high income elasticity of demand fortion growth, technological and science break- meat and other livestock products (Delgado etthroughs, political changes, and economic al., 1999) – that is, as incomes grow, expenditureand trade liberalization have all contributed to on livestock products grows rapidly. Thereforeeconomic growth. In developing countries, this growing per capita incomes will translate intogrowth has translated into rising per capita growing demand for these products. This willincomes, and an emerging middle class that has close much of the gap in average consumptionpurchasing power beyond their basic needs. figures of meat, milk and eggs that currently Over the decade 1991 to 2001, per capita GDP exists between developed and developing coun-grew at more than 1.4 percent a year for the tries. As Figure 1.4 shows, the effect of increasedworld as a whole. Developing countries grew at income on diets is greatest among lower- and2.3 percent on average compared to 1.8 percent middle-income populations. This observation isfor developed countries (World Bank, 2006). true at individual level as well as at the nationalGrowth has been particularly pronounced in East level (Devine, 2003).Asia with an annual growth rate of close to seven Figure 1.4 The relationship between meat consumption and per capita income in 2002 140 USA 120 Russian Federation 100 Per capita meat consumption (kg) Brazil 80 China 60 Japan 40 Thailand 20 India 0 0 5 000 10 000 15 000 20 000 25 000 30 000 35 000 40 000 Per capita income (US$ PPP) Note: National per capita based on purchasing power parity (PPP). Source: World Bank (2006) and FAO (2006b). 
    • Livestock’s long shadowThe nutrition transition Figure 1.5 Past and projected food consumption Worldwide shifts in dietary preferences of livestock productsThe advent of agriculture and the sedentariza- 1 000 projectionstion of hunter/gatherers enabled increasing 900populations to be fed – but it also led to a nar- 800rowing of the human diet. Prior to agriculture, 700 Kcalories/person/dayanimal products played a much larger role in 600human nutrition, and intake levels were similar 500to, if not higher than, current consumption lev- 400els in developed countries. Increases in income 300 200and advances in agriculture enabled developed 100countries to enrich and diversify their diets over 0the last 150 years. Developing countries are cur- 1962 1970 1980 1990 2000 2015 2030 2050rently engaged in a catching-up process, which Industrialized Near East/North Africahas been termed the “nutrition transition” by Transition South Asia Latin America and the Caribbean Sub-Saharan AfricaPopkins, Horton and Kim, (2001). The transition East Asiais characterized by an accelerated shift fromwidespread undernourishment to richer and Note: For past, three-year averages centered on the indicated year. Livestock products include meats, eggs,more varied diets and often to overnutrition. In milk and dairy products (excluding butter).contrast to the more secular nutrition transition Source: FAO (2006a) and FAO (2006b).that occurred in developed countries, this shiftnow occurs within a single generation in rapidlygrowing developing countries. by reduced physical activity, leading to a rapid With higher disposable incomes and urbaniza- increase in overweight and obesity (Popkin, Hor-tion, people move away from relatively monoto- ton and Kim, 2001). Worldwide the number ofnous diets of varying nutritional quality (based on overweight people (about 1 billion) has nowindigenous staple grains or starchy roots, locally surpassed the number of malnourished peoplegrown vegetables, other vegetables and fruits, (about 800 million). And a significant part ofand limited foods of animal origin) towards more the growth in obesity occurs in the developingvaried diets that include more pre-processed world. For example, the World Health Organiza-food, more foods of animal origin, more added tion (WHO) estimates that there are 300 millionsugar and fat, and often more alcohol (Table obese adults and 115 million suffering from obe-1.2 and Figure 1.5). This shift is accompanied sity-related conditions in the developing world.1 A rapid increase in diet-related chronic diseases, including heart disease, diabetes, hypertensionTable 1.2 and certain cancers is associated with the rapidChanges in food consumption in developing countries nutrition transition. In a number of developing 1962 1970 1980 1990 2000 2003 countries, diet-related chronic diseases have Consumption kg/person/year become a priority in national food and agricul-Cereals 132 145 159 170 161 156 tural policies, which now promote healthy eatingRoots and tubers 18 19 17 14 15 15 habits, exercise and school-based nutrition pro-Starchy roots 70 73 63 53 61 61 grammes (Popkin, Horton and Kim, 2001).Meat 10 11 14 19 27 29 The nutrition transition is driven by risingMilk 28 29 34 38 45 48 1 Available at: www.fao.org/FOCUS/E/obesity/obes1.htmSource: FAO (2006b).10
    • Introductionincomes and by the continuing trend to lower food products or opt for certified products, suchrelative prices for food. Prices have been declin- as free range or organic foods (Krystallis anding in real terms since the 1950s. Currently they Arvanitoyannis, 2006; King, et al., 2000). Theallow much higher consumption levels of high- growing trend towards vegetarianism, albeit stillvalue food items than was the case for developed at a very low level in most societies, is anothercountries at comparable levels of income in the manifestation of this trend. Government promo-past (Schmidhuber and Shetty, 2005). tion campaigns are also identified as potential While purchasing power and urbanization drivers of consumption trends (Morrison et al.,explain the greater part of the per capita con- 2003).sumption pattern, other social and cultural fac-tors can have a large influence locally. For exam- Technological changeple, Brazil and Thailand have similar income Growing productivityper capita and urbanization rates but animal The livestock sector has been affected by pro-product consumption in Brazil is roughly twice found technological change on three differentas high as in Thailand. The Russian Federation fronts:and Japan have similar consumption levels for • In livestock production, the widespread appli-animal-derived foods, yet income levels in Japan cation of advanced breeding and feeding tech-are about 13 times higher than in Russia (see nology has spurred impressive productivityfigure 1.4). growth in most parts of the world. Natural resource endowment is one of the • In crop agriculture, irrigation and fertiliza-additional factors determining consumption, as tion techniques, combined with the use ofit shapes the relative costs of different food com- improved varieties and mechanization, con-modities. Access to marine resources, on the one tinue to translate into growing yields andhand, and to natural resources for livestock pro- improved nutrient composition in pasture andduction, on the other, have drawn consumption major crops used for feed.trends in opposite directions. Lactose intoler- • The application of modern information tech-ance, found particularly in East Asia, has limited nology and other technical changes aremilk consumption. Cultural reasons have further improving post-harvest, distribution and mar-influenced consumption habits. This, for exam- keting of animal products.ple, is the case in South Asia, where consumption In animal production, technological develop-per capita of meat is lower than income alone ment has been most rapid in those subsectorswould explain. Other examples are the exclu- that have experienced the fastest growth: broilersion of pork from the diet by Muslims. Socio- and egg production, pork and dairy. Productivitycultural patterns have created a rich diversity of growth, and the underlying spread of advancedconsumer preferences, but have also influenced technologies, has been less pronounced for beefconsumers’ views about the quality of animal and meat from small ruminants. However, cer-products (Krystallis and Arvanitoyannis, 2006). tain key technological changes have occurred in More recently, consumption patterns are the production of all livestock commodities – aincreasingly influenced by growing concerns growing production intensity, characterized byabout health, the environment, ethical, animal increasing use of feed cereals, use of advancedwelfare and development issues. In countries of genetics and feeding systems, animal healththe Organisation for Economic Co-operation and protection and enclosure of animals. AdvancesDevelopment (OECD) a class of “concerned con- in these areas go hand in hand, and it is difficultsumers” has emerged, who (Harrington, 1994) to separate out the effect of individual factors ontend to reduce their consumption of livestock overall productivity increases. 11
    • Livestock’s long shadowIncreased grain feeding Table 1.3Traditionally, livestock production was based Use of feed concentrateon locally available feed resources such as crop Feed concentrate use in 2002 (million tonnes)wastes and browse that had no value as food.However, as livestock production grows and Commodity group Developing Developed World countries countriesintensifies, it depends less and less on locallyavailable feed resources, and increasingly on Grains 226.4 444.0 670.4feed concentrates that are traded domestically Brans 92.3 37.0 129.3and internationally. In 2002, a total of 670 million Oilseeds and pulses 11.6 15.7 27.3tonnes of cereals were fed to livestock, repre- Oilcakes 90.5 96.6 187.3senting roughly one-third of the global cereal Roots and tubers 57.8 94.6 152.4harvest (see Table 1.3). Another 350 million Fish meal 3.8 3.8 7.6tonnes of protein-rich processing by-products Total of above 482.4 691.71 1 174.1are used as feed (mainly brans, oilcakes and Source: FAO (2005).fishmeal). Monogastric species that can most efficientlymake use of concentrate feeds, i.e. pigs, poultry tributor to growing supplies in many developingand dairy cattle, have an advantage over beef countries, especially in Latin America (where thecattle, sheep and goats. Among the monogas- cropped area expanded by 15 percent betweentrics, poultry has shown the highest growth rates 1980 and 2003) and sub-Saharan Africa (22 per-and lowest prices, mainly because of favourable cent). Land-scarce Asia (developing) has seenfeed conversion rates. The use of feed con- a modest 12 percent expansion of the croppedcentrate for ruminants is limited to countries area. Some countries have seen a particularlywhere meat prices are high relative to grain strong expansion of area cropped, most of it atprices. Where grain prices are high relative to the expense of forest (Brazil and other Latinmeat prices – typically in food-deficit develop- American countries). Much of this area expan-ing countries – grain feeding to ruminants is not sion has been for the production of concentrateprofitable. feeds for livestock, notably soybeans and maize. What is driving the increasing use of feed Feed conversion and growth rates have beengrains? Most importantly, there is a long-term greatly improved by use of linear programmingdecline of grain prices; a trend that has persisted to develop least-cost feed rations, phased feed-since the 1950s. Supply has kept up with grow- ing and the use of enzymes and synthetic amino-ing demand: total supply of grains increased by acids, together with a much extended use of feed43 percent over the last 24 years (1980 to 2004). concentrates (grains and oilcakes).In real terms (constant US$), international pric- In future, feed concentrate use is projectedes for grains have halved since 1961. Expanding to grow more slowly than livestock produc-supply at declining prices has been achieved by tion, despite the fact that the latter is becom-area expansion and by intensification of crop ing increasingly cereal-based. This is becauseproduction. improved technologies in feeding, breeding and Intensification accounts for the bulk of supply animal health are producing even greater effi-expansion over the past 25 years, and is a result ciency gains.of technological advances and higher input usein crop production – notably plant breeding, More productive breedsthe application of fertilizers and mechanization. In animal genetics and breeding, the use ofArea expansion has been an important con- hybridization and artificial insemination has12
    • Introductionsped up the process of genetic improvement. sive livestock enterprises in the tropics usu-In poultry, for example, these techniques have ally control the climatic and health environmentgreatly expanded the number of animals that around the animals, so as to utilize the efficien-can be bred from a superior parent stock, creat- cies of modern breeds developed for temperateing animals with uniform characteristics (Fuglie regions.et al., 2000). Traditionally, the only means of Animal health improvements have furthergenetic improvement was selection based on contributed to raising productivity, including thethe phenotype. Starting from the beginning of use of antibiotics (now banned for use in growththe twentieth century, technologies such as enhancement in areas such as the Europeancontrolled management of reproduction and of Union (EU) in special pathogen-free productionpedigrees were developed. These were initially environments. In developing countries, theselimited to purebred stock (Arthur and Albers, technologies have spread widely in recent years,2003). Around mid-century, line specialization particularly in industrial production systemsand cross-breeding were initiated, first in North close to major consumption centres. The con-America, then in Europe and other OECD coun- tinuous increase in scales of production has alsotries. Artificial insemination was first introduced led to important productivity gains in developingin the 1960s and is now commonplace in all countries. These have allowed animal prod-intensive livestock production systems. Around ucts to be supplied to growing populations atthe same time, breeding value evaluation tech- decreasing real prices (Delgado et al., 2006).nologies were introduced in developed countries.More recent innovations include the use of DNA Cheaper feed grainsmarkers to identify specific traits. In crop production, similar improvements have Breeding goals have changed considerably improved supply and reduced prices of feedover time, but the speed and precision with grains, with important productivity increaseswhich these goals can be achieved has increased occurring earlier (in the 1960s and 1970s) thanconsiderably over recent decades. Short-cycle for livestock (FAO, 2003a). For developing coun-species, such as poultry and pigs, have a distinct tries, about 80 percent of the projected growth inadvantage over species having a longer genera- crop production to 2030 will come from intensifi-tion interval. Among all species, feed conversion cation, mostly in the form of yield increases, andand related parameters such as growth rate, also through higher cropping intensities. Irriga-milk yield and reproductive efficiency are para- tion is a major factor in land intensification: themount factors for breeding (Arthur and Albers, irrigated area in developing countries doubled2003). Fat content and other features that corre- between 1961–63 and 1997–99 and is expectedspond best to consumer demands are increasing to increase by another 20 percent by 2030 (FAO,in importance. 2003a). Widespread application of fertilizer and These changes have brought about impressive improved fertilizer composition and forms ofresults. For example, Arthur and Albers (2003) application are other important factors in cropreport that in the United States, feed conver- intensification, along with improvements in plantsion ratios for eggs have been reduced from protection.2.96 grams of feed per gram of egg in 1960 to The post-harvest sector, distribution and mar-2.01 grams in 2001. keting have seen profound structural changes. The breeding industry has been less suc- These are associated with the emergence ofcessful in developing breeds of dairy cows, pigs large retailers, with a tendency towards verticaland poultry that perform well in non-modified integration and coordination along the food chain.tropical low-input environments. Highly inten- This trend has been brought about by liberaliza- 13
    • Livestock’s long shadowTable 1.4Key productivity parameters for livestock in different world regionsRegion Chicken meat Egg yield Pig meat (kg output/kg biomass/year)1 (kg/layer/year) (kg output/kg biomass/year)1 1980 2005 1980 2005 1980 2005World 1.83 2.47 8.9 10.3 0.31 0.45Developing countries 1.29 1.98 5.5 8.8 0.14 0.33Developed countries 2.26 3.55 12.2 15.0 0.82 1.20Sub-Saharan Africa 1.46 1.63 3.4 3.6 0.53 0.57West Asia and North Africa 1.73 2.02 7.0 9.4 1.04 1.03Latin America and the Caribbean 1.67 3.41 8.6 9.8 0.41 0.79South Asia 0.61 2.69 5.8 8.1 0.72 0.71East and Southeast Asia 1.03 1.41 4.7 9.5 0.12 0.31Industrialized countries 2.45 3.72 14.1 16.0 1.03 1.34Transition countries 1.81 2.75 9.6 13.0 0.57 0.75Region Beef Small ruminants Milk yield (kg output/kg biomass/year)1 (kg output/kg biomass/year)1 (kg/cow/year) 1980 2005 1980 2005 1980 2005World 0.11 0.13 0.16 0.26 1 974 2 192Developing countries 0.06 0.09 0.14 0.26 708 1 015Developed countries 0.17 0.21 0.19 0.24 3 165 4 657Sub-Saharan Africa 0.06 0.06 0.15 0.15 411 397West Asia and North Africa 0.07 0.10 0.21 0.25 998 1 735Latin America and the Caribbean 0.08 0.11 0.11 0.13 1 021 1 380South Asia 0.03 0.04 0.16 0.23 517 904East and Southeast Asia including China 0.06 0.16 0.05 0.20 1 193 1 966Industrialized countries 0.17 0.20 0.20 0.25 4 226 6 350Transition countries 0.18 0.22 0.17 0.23 2 195 2 7541 Biomass is calculated as inventory x average liveweight. Output is given as carcass weight.Source: FAO (2006b).tion of markets and widespread application of small wealthy class elsewhere. At that time,new technologies in logistics and organizational most developing countries, with the exception ofmanagement transport. All of these help to bring Latin America and some West Asian countriesprices down for consumers – but at the same had an annual per capita meat consumption oftime they raise entry barriers for small produc- substantially less than 20 kg. For most peopleers (Costales, Gerber and Steinfeld, 2006). in Africa and Asia, meat, milk and eggs were an unaffordable luxury, consumed only on rare1.3 Trends within the livestock sector occasions. A high proportion of the larger live-Until about the early 1980s, diets that included stock in developing countries was not primarilydaily consumption of milk and meat were largely kept for food, but for other important functions,the privilege of OECD country citizens and a such as providing draught power and manure,14
    • Introductionand serving as an insurance policy and a capital Figure 1.6 Past and projected meat production asset, usually disposed of only in times of com- in developed and developing countries from 1970 to 2050munal feasting or emergency. This is changing rapidly. The livestock sector is 350 projectionscurrently growing faster than the rest of agricul- 300ture in almost all countries. Typically, its share 250 Million tonnesin agricultural GDP rises with income and level 200of development and is above 50 percent for most 150OECD countries. The nature of livestock produc- 100tion is also changing rapidly in many emerging 50economies, as well as in developed countries. 0 1970 1975 1980 1985 1990 1995 2000 2015 2030 2050Most of this change can be summarized under Developed countries Developing countriesthe term “industrialization”. Through industri-alization, livestock escape most of the environ- Source: FAO (2006a) and FAO (2006b).mental constraints that have shaped livestockproduction diversely in the wide range of envi-ronments in which they occur. Figure 1.7 Past and projected milk production in developed and developing countries from 1970 to 2050Livestock production and consumption booms inthe south, stagnates in the north 700Driven by population growth and rising income projections 600in many developing countries, the global live- 500stock sector has seen a dramatic expansion Million tonnes 400over the past decades, though with considerable 300differences between developing and developed 200countries. 100 In the developing countries, annual per 0capita consumption of meat has doubled since 1970 1975 1980 1985 1990 1995 2000 2015 2030 20501980, from 14 kg to 28 kg in 2002 (Table 1.5). Developed countries Developing countries Total meat supply tripled from 47 milliontonnes to 137 million tonnes over the same peri- Source: FAO (2006a) and FAO (2006b).od. Developments have been most dynamic inTable 1.5Past and projected trends in consumption of meat and milk in developing and developed countries Developing countries Developed countries 1980 1990 2002 2015 2030 1980 1990 2002 2015 2030Food demandAnnual per capita meat consumption (kg) 14 18 28 32 37 73 80 78 83 89Annual per capita milk consumption (kg) 34 38 46 55 66 195 200 202 203 209Total meat consumption (million tonnes) 47 73 137 184 252 86 100 102 112 121Total milk consumption (million tonnes) 114 152 222 323 452 228 251 265 273 284Source: FAO (2006a) and FAO (2006b). 15
    • Livestock’s long shadowTable 1.6Developing country trends in livestock production in 2005Country Group/Country Meat Milk Percentage of developing country production (million tonnes) (million tonnes) Meat MilkDeveloping countries 155.0 274.1 100.0 100.0China 75.7 28.3 48.8 10.3Brazil 19.9 23.5 12.8 8.6India 6.3 91.9 4.1 33.5Source: FAO (2006b).countries that have seen rapid economic growth, as the booming poultry industry will pose feednotably East Asia, led by China. China alone demands that will far exceed current supplies.accounted for 57 percent of the increase in total In contrast, Argentina, Brazil and other Latinmeat production in developing countries. For American countries have successfully expandedmilk, developments are less spectacular but still their domestic feed base, taking advantage ofremarkable: total milk production in develop- low production costs and abundance of landing countries expanded by 118 percent between (Steinfeld and Chilonda, 2006). They have moved1980 and 2002, with 23 percent of that increase to adding value to feed, rather than exportingcoming from one country, India. it. They are poised to become the major meat- This dramatic increase in demand for live- exporting region supplying developed and Eaststock products (a transition called the “livestock Asian countries.revolution” by Delgado et al., 1999), is poised to In the developing countries, livestock produc-continue for another 10 to 20 years before slow- tion is rapidly shifting towards monogastrics Ining down (Delgado et al., 1999). A few developing fact, poultry and pigs account for 77 percent ofcountries, notably Brazil, China and India are the expansion in production. While total meatemerging as world players as their strength as production in developing countries more than tri-trading partners is growing rapidly (Steinfeld and pled between 1980 and 2004, the growth in rumi-Chilonda, 2005). These three countries account nant production (cattle, sheep and goats) wasfor almost two-thirds of total meat production in only 111 percent, that of monogastrics expandeddeveloping countries and for more than half of more than fourfold over the same period.the milk (Table 1.6). They also account for close These dramatic developments in rapidly grow-to three–quarters of the growth in milk and meat ing developing countries are in stark contrastproduction in all developing countries. with trends in developed countries, where con- There is a great deal of variation in the extent sumption of livestock products is growing onlyand character of livestock sector growth. China slowly or stagnating. With low or no popula-and East Asia have experienced the most impres- tion growth, markets are saturated in mostsive growth in consumption and production, first developed countries. Consumers are concernedin meat and more recently also in dairy. The about the health effects of high intake levels ofregion will need to import increasing amounts livestock products, in particular red meat andof feed, and perhaps also livestock products, to animal fats. Continuous high-level consumptionmeet future consumption growth. In contrast, of these products is associated with a series ofIndia’s livestock sector continues to be dairy- cardio-vascular diseases and certain types oforiented, using traditional feed resources and cancer. Other perceived health problems asso-crop residues. This picture is likely to change, ciated with animal products sporadically and16
    • Introductionsometimes permanently suppress demand for Most of the expansion in the supply of livestockanimal products. These include the presence of products in developing countries comes fromresidues (of antibiotics, pesticides, dioxins) and increased production, and only a relatively smallof pathogens (Escherichia coli, salmonella, mad part from imports. For developing countries ascow disease). a whole, net imports account for only about 0.5 In developed countries, total livestock produc- percent of total supply for meat, and 14.5 percenttion increased by only 22 percent between 1980 for milk (FAO, 2006b). However, trade in livestockand 2004. Ruminant meat production actually products has increased much faster than tradedeclined by 7 percent while that of poultry and in feed. For feedgrains, the traded share of totalpigs increased by 42 percent. As a result, the production has remained fairly stable in theshare of production of poultry and pigs has gone range of 20 to 25 percent over the last decade.up from 59 to 69 percent of total meat produc- The share for meat increased from 6 percent intion. Among the monogastrics, poultry is the 1980 to 10 percent in 2002, and for milk from 9 tocommodity with the highest growth rates across 12 percent over the same period.all regions. A main reason for this, apart from Growth in trade in livestock products is alsovery favourable feed conversion, is the fact that outpacing that of growth in production, facilitat-poultry is a meat type acceptable to all major ed by declining tariff barriers within the contextreligious and cultural groups. of the General Agreement on Tariffs and Trade A few general observations can be made. The (GATT). This indicates a gradual trend towardstrend towards rapidly increasing livestock pro- producing livestock in locations where feed isduction in the tropics poses a series of technical available, rather than close to consumption cen-problems, such as those related to climate and tres ‑ a trend made possible by infrastructuredisease. Countries do not appear to be readily development and the establishment of refriger-prepared for some of these, as has been dem- ated supply chains (“cold chains”) in major pro-onstrated by the outbreaks of avian influenza in ducing countries.the last two years. The surge in production alsoentails an expansion of feed supplies and, partic- Structural changeularly in Asia, an increasing amount will need to The large increases in supply of livestock prod-come from imports. Some countries will be faced ucts have been facilitated by structural adjust-with the question whether to meet this demand ments in the sector, including growing inten-by importing feed for domestic livestock produc- sities (discussed above), increasing scales oftion or to opt for imports of livestock products. production, vertical integration and geographicalProduction is also moving away from established shifts.production areas that have high environmentalstandards. This potentially creates opportunities Units scale up in size, while smallholdersfor evading environmental controls. are marginalized On the consumption side, there is a trend There has been a rapid growth in the averagetowards global convergence of diets. Cultural size of primary production units, accompanied bypeculiarities, though still strong in some areas, a substantial decline in the numbers of livestockbecome increasingly blurred as demonstrated by producers in many parts of the world. The majorthe surge of poultry consumption in South and driver of this process is the cost reduction thatEast Asia. This convergence is further driven by can be realized through the expansion of scalethe fact that similar eating habits, such as fast of operations at various stages of the productionand convenience food, are catching hold almost process. Smallholders may stay in the livestockeverywhere. business by selling their products at prices that 17
    • Livestock’s long shadow Narrod, 2006) show the substantial impact of hidden and overt subsidies that facilitate the supply of cheap animal products to the cities, to the disadvantage of small-scale rural producers. There is often no public support to adapt or dis-© FAO/23785/R. Lemoyne seminate new technologies for small-scale use. Production costs are higher at the smallholder level because of both market and production risks. Market risks include price fluctuations for both inputs and products. These are often ampli- A Maasai woman carrying a baby on her back milks fied for smallholders because of their weak a cow as its calf attempts to nurse. A gourd is used negotiating position. Some small-scale produc- to collect the milk. The cattle are kept over night inside the perimeter of the boma to protect them from ers evolved from subsistence farming with sound wildlife – Kenya 2003 risk coping mechanisms, but lack the assets or strategies to sustain full exposure to market risks. The absence of safety nets in the face of value their own labour input below the market economic shocks, invariably present in such rate. However, this occurs mostly in countries markets, restricts the participation of small- with limited employment opportunities in other holders. Production risks relate to resource sectors. As soon as employment opportunities in degradation, control of assets such as land and other sectors arise, many smallholder produc- water, climatic variations such as droughts and ers opt out of livestock production. floods, and infectious diseases. Different commodities and different steps of Smallholders face additional problems the production process offer different potential because of the transaction costs involved in for economies of scale. The potential tends to product marketing. These are often prohibi- be high in post-harvest sectors (slaughterhouse, tively high because of the small quantities of dairy plants). Poultry production is most easily marketable product produced and the absence mechanized, and industrial forms of production of adequate physical and market infrastruc- emerge even in least developed countries. In tures in remote areas. Transaction costs are contrast, dairy production shows fewer econo- also increased where producers lack negotiat- mies of scale because of the typically high labour ing power or access to market information, and input. As a result, dairy production continues to remain dependent on intermediaries. Moreover, be dominated by family-based production. the frequent absence of producers’ associa- For dairy and small ruminant production, tions or other partnership arrangements makes farm-level production costs at the smallholder it more difficult for smallholder producers to level are often comparable with those of large- reduce transaction costs through economies of scale enterprises, usually because of the cost scale. advantages of providing family labour below the The desire to reduce transaction costs is a level of the minimum wage. However, the expan- main force promoting vertical integration in sion of smallholder production beyond a semi- developed and developing countries alike. In subsistence level is constrained by a number of developing countries, it is found particularly in barriers, lack of competitiveness and risk factors poultry and pork, but also in dairy production. (see below). These economic forces are sometimes further Access to land and credit is an increasing strengthened if governments tax market trans- problem. Recent LEAD studies (Delgado and actions, for example for feed, as described by 18
    • IntroductionDelgado and Narrod (2002) in the case of poultry At a later stage, livestock production shiftsproducers in Andhra Pradesh (India). The com- even further from demand centres, driven bybined effect of economic gains from lowering factors such as lower land and labour prices,transaction costs by vertical integration, and access to feed, lower environmental standards,more favourable tax regimes for larger enter- tax incentives or locations with fewer diseaseprises, tends to disadvantage independent and problems. The LEAD study found that the poultrysmall-scale producers severely. density in areas closer than 100 km to Bangkok decreased between 1992 and 2000, with the larg-Geographic shifts est decrease (40 percent) in the areas close toProduction grows more concentrated the city (less than 50 km). Density increased inTraditionally, livestock production was based all areas further away than 100 km (Gerber eton locally available feed resources, particularly al., 2005).those having limited or no alternative use value, The LEAD study found that for all countriessuch as natural pasture and crop residues. The analysed (Brazil, France, Mexico, Thailand, Vietdistribution of ruminants was almost completely Nam), despite the variety of factors that deter-determined by the availability of such resources. mine optimal location, there is a continuingThe distribution of pigs and poultry followed process of concentration for all species coveredclosely that of humans, because of their role as by the analysis (cattle, chicken and pigs). Even inwaste converters. For example, a LEAD study in developed economies, the trend of concentrationViet Nam (a country in its early stages of indus- and increasing scale is continuing.trialization) found that 90 percent of the poultrydistribution pattern could be explained by the Vertical integration and the rise ofdistribution of the human population (Tran Thi supermarketsDan et al., 2003). Large multinational firms are becoming domi- In the course of development, the livestock nant in the meat and dairy trade, both in thesector strives to free itself from local natural developed world and in many developing coun-resource constraints – but becomes subject tries experiencing fast livestock sector growth.to a different set of factors that shape its geo- Their strength is linked to achieving economiesgraphical distribution and concentration. The of size and scope, and to sourcing supplies atimportance of agro-ecological conditions as adeterminant of location is replaced by factorssuch as opportunity cost of land and access tooutput and input markets. As soon as urbanization and economic growthtranslate rising incomes into “bulk” demandfor animal source food products, large-scaleoperators emerge. At the initial stage, theseare located close to towns and cities. Livestockproducts are among the most perishable foodproducts, and their conservation without chilling © LEAD/Pierre Gerberand processing poses serious quality and humanhealth problems. Therefore, livestock have to beproduced close to the location of demand, unlessthere is adequate infrastructure and technologyto permit livestock to be kept farther away. Breeding sows in Rachaburi – Thailand 2004 19
    • Livestock’s long shadowdifferent levels and across national boundaries. In summary, the trends in the global livestockVertical integration allows not only for gains from sector can be described as follows:economies of scale. It also secures benefits from • Demand and production of livestock productsmarket ownership and from control over product are increasing rapidly in developing countriesquality and safety, by controlling the technical that have outpaced developed countries. Ainputs and processes at all levels. few large countries are taking centre stage. The rapid expansion of supermarkets and Poultry has the highest growth rate.fast food outlets in developing countries started • This increasing demand is associated within the 1990s and has already large segments important structural changes in countries’of the market in Latin America, East Asia and livestock sectors, such as intensification ofWest Asia; this process has now also started production, vertical integration, geographicin South Asia and sub-Saharan Africa. This concentration and up-scaling of productionexpansion has been accompanied by a relative units.decline of traditional “wet” and local markets. • There are concomitant shifts towards poultryFor example, in China the number of supermar- and pig meat relative to ruminant meat, andket outlets rose from 2 500 in 1994 to 32 000 in towards grain- or concentrate-based diets2000 (Hu and Reardon, 2003). The supermarket relative to low-value feed.share of total retail turnover is estimated to have These trends indicate a growing impact on thereached about 20 percent of the total packaged environment, as will be shown in more detailand processed food retailing (Reardon et al., in the following chapters. Growth in itself may2003). According to the same authors, the share be regarded as a problem as it is not offset byof supermarkets in the retailing of fresh foods is concomitant productivity gains. Although theseabout 15 to 20 percent in Southeast Asia. India are important, the expanding livestock sectorstill has a comparatively low supermarket share lays hands on additional feed and land resourcesof only 5 percent. As is already the case in devel- that come at significant environmental costs.oped countries, the large-scale retail sector is Structural change also modifies the nature ofbecoming the dominant actor in the agrifood damage. In addition to issues associated withsystem. extensive production, such as overgrazing, there The rise of supermarkets has been facilitated is a steep increase in those connected to inten-by innovations in retail procurement logistics, sive and industrial forms, such as concentrationtechnology and inventory management in the of pollutants, expansion of arable land for feed1990s, with the use of the Internet and informa- and environmental health problems. Further,tion management technology. This has enabled the shift to traded and processed feeds spreadscentralized procurement and consolidated dis- the environmental problems to other sectors,tribution. The technological change, led by global e.g. feedcrop production, fisheries, and to otherchains, is now diffusing around the world through parts of the world, which often obscures the realknowledge transfer, and imitation by domestic nature and extent of environmental impact.supermarket chains. The substantial savingsfrom efficiency gains, economies of scale andcoordination cost reduction provide profits forinvestment in new stores, and, through intensecompetition, reduce prices to consumers. Therequirements of these integrated food chains, interms of volume, quality, safety, etc. are becom-ing pervasive throughout the livestock sector.20
    • 02
    • Livestock in geographic transitionT his chapter deals with the changing use of land1 by livestock and some of the environ-mental impacts of that use2. Land management Land use has both spatial and temporal dimen- sions. Types of land use can spread or shrink, scatter or concentrate, while land use at a singlehas a direct impact on the biophysical conditions location can be stable, seasonal, multiple and/orof the land including soil, water, fauna and flora. transitory. Land use is driven by a wide range of factors: some are endogenous to the land (e.g. bio-physical characteristics), some relate to the1 With UNEP (2002), we define land as the terrestrial biopro- individual or the society using the land (e.g. ductive system that comprises soil, vegetation ‑ including capital availability, technical knowledge), some, crops, other biota, and the ecological and hydrological pro- finally, depend on the institutional and economic cesses that operate within the system”.2 Land-use changes include land cover-changes as well as framework in which the land-user operates (e.g. the changing ways in which the land is managed. Agricul- national policies, markets, services). tural land management refers to the practices by which Access to land and its resources is becom- humans use vegetation, water and soil to achieve a given ing an increasingly acute issue and source of objective. e.g. use of pesticides, mineral fertilizers, irrigation and machinery for crop production (Verburg, Chen and Veld competition among individuals, social groups Kamp, 2000). and nations. Access to land has driven disputes
    • Livestock’s long shadowand wars throughout history and, in some areas, Figure 2.1 Estimated changes in land use resource-related conflicts are on the increase. from 1700 to 1995For example, disputes over access to renewable 100resources, including land, are one of the principal Percentage of total land areapathways in which environmental issues lead to 75armed conflicts (Westing, Fox and Renner, 2001). 50This may be the result of a reduced supply of land(because of depletion or degradation), distribu- 25tion inequities or a combination of these factors.Increasing land prices also reflect the increasing 0 1700 1800 1900 1980competition for land. (MAFF‑ UK, 1999). Year Other Forest Pasture Cropland In this chapter, we will first look at the broadtrends in land use and the forces that drive Source: Goldewijk and Battjes (1997).them, and introduce the “livestock transition” asa basic concept central to the understanding oflivestock‑environment interactions. We will thentake a closer look at how the demand for live- Table 2.1 presents regional trends over thestock food products is distributed in relation to past four decades for three classes of land use:population and income. We will then turn to the arable land, pasture and forest. In North Africa,geographic distribution of the natural resource Asia, Latin America and the Caribbean land usebase for livestock production, especially feed for agriculture, both for arable and pasture, isresources. This includes grazing land and arable expanding. The expansion of agriculture is fast-land, particularly where surplus crop production est in Latin America and sub-Saharan Africa,is being used as feed for livestock production. mostly at the expense of forest cover (WassenaarResources for livestock production and demand et al., 2006). In Asia (mostly Southeast Asia)for animal products are balanced through live- agriculture is expanding, and showing even astock production systems that interact with both slight acceleration. In contrast, North Africa hasthe resources and demand side. We will look at seen crop, pasture and forestry expanding atthe changing geography of production systems only modest rates, with low shares of total landand the way transport of feed and animal prod- area covered by arable land. Oceania and sub-ucts resolve geographical mismatches and bring Saharan Africa have limited arable land (lessabout different competitive advantages. Finally, than 7 percent of total land) and vast pasturewe will review the main land degradation issues land (35 to 50 percent of total land). Expansion ofrelated to the livestock sector. arable land has been substantial in Oceania and is accelerating in sub-Saharan Africa. There is a2.1 Trends in livestock-related net reduction of forest land in both regions. Localland use studies have also found replacement of pasture2.1.1 Overview: a regionally diverse by cropland. In sub-Saharan Africa, where crop-pattern of change ping and grazing are often practised by differentThe conversion of natural habitats to pastures ethnic groups, the advance of crops into pastureand cropland has been rapid. Conversion accel- land often results in conflict, as shown by majorerated after the 1850s (Goldewijk and Battjes, disturbances in the Senegal river basin between1997) (Figure 2.1). More land was converted to Mauritania and Senegal, and in North Easterncrops between 1950 and 1980 than in the preced- Kenya, between the Boran and the Somalising 150 years (MEA, 2005a). (Nori, Switzer and Crawford, 2005).24
    • Livestock in geographic transition Box 2.1 Recent trends in forestry expansion The Global Forest Resources Assessment 2005 estation in China, and continued to increase in suggests that forest still covers less than 4 billion Europe, although at a slowing pace. Primary forest hectares, or 30 percent of the total land surface area in Europe and Japan is expanding, thanks to area. This area has been in continuous decrease, strong protection measures. although at a slowing pace. The net loss in forest Forest cover embraces a range of land usages. area is estimated at 7.3 million hectares per year Wood production continues to be a major func- over the period 2000 to 2005, compared to 8.9 mil- tion in many forests. Trends are diverging though: lion hectares per year over the period 1990 to 2000. Africa showed a steady increase in wood removal Plantation forests are generally increasing but still over the period 1990 to 2005, while production is account for less than 4 percent of total forest area decreasing in Asia. Forests are increasingly desig- (FAO, 2005e). On average, 2.8 million hectares of nated for the conservation of biodiversity. This kind forest were planted each year over the period 2000 of forest (mainly in protected areas) increased by to 2005. an estimated 96 million hectares over the 1990 to These global figures mask differences among 2005 period, and by 2005 accounted for 11 percent regions and forest types. Africa, North, Central of all forests. Soil and water conservation is seen and South America and Oceania showed net forest as a dominant function for 9 percent of the world’s cover losses over the period 2000 to 2005 (FAO, forests. 2005e), with the two latter bearing the largest losses. In contrast, forest cover increased in Asia over the same period, owing to large-scale refor- Source: FAO (2005e). Western Europe, Eastern Europe and North The massive expansion of arable and pastureAmerica show a net decrease in agricultural land over the last four decades has started toland use over the last four decades, coupled with slow (Table 2.1). At the same time, human popu-stabilization or increase in forest land. These lations grew more than six times faster, withtrends occur in the context of a high share of annual growth rate estimated at 1.9 percent andland dedicated to crops: 37.7 percent, 21 percent 1.4 percent over the 1961–1991 and 1991–2001and 11.8 percent in Eastern Europe, Western periods respectively.Europe and North America, respectively. TheBaltic States and Commonwealth of Indepen- Extensification gives way to intensificationdent States (CIS) states show an entirely differ- Most of the increase in food demand has beenent pattern, with decreasing land dedicated to met by intensification of agricultural land usecrops and increasing land dedicated to pasture. rather than by an expansion of the productionThis trend is explained by economic regression area. The total supply of cereals increased bycausing the abandonment of cropland, and by 46 percent over the last 24 years (1980 to 2004),structural and ownership changes that occurred while the area dedicated to cereal productionduring transition in the 1990s. Map 1 (Annex 1) shrank by 5.2 percent (see Figure 2.2). In devel-further shows the uneven geographical distri- oping countries as a whole, the expansion of har-bution of cropland, with vast areas remaining vested land accounted for only 29 percent of themostly uncropped on all continents. The main growth in crop production over the period 1961–patches of highly intensive cropping are found in 99, with the rest stemming from higher yieldsNorth America, Europe, India and East Asia. and cropping intensities. Sub-Saharan Africa, 25
    • Livestock’s long shadowTable 2.1Regional trends in land use for arable land, pasture and forest from 1961 to 2001 Arable land Pasture Forest Annual Annual Annual Share Share Share growth rate growth rate growth rate of total of total of total (%) (%) (%) land in land in land in 1961– 1991– 2001 1961– 1991– 2001 1961– 1990– 20022 1991 2001 (%) 1991 2001 (%) 1991 20002 (%)Developing Asia1 0.4 0.5 17.8 0.8 0.1 25.4 -0.3 -0.1 20.5Oceania 1.3 0.8 6.2 -0.1 -0.3 49.4 0.0 -0.1 24.5Baltic states and CIS -0.2 -0.8 9.4 0.3 0.1 15.0 n.d. 0.0 38.3Eastern Europe -0.3 -0.4 37.7 0.1 -0.5 17.1 0.2 0.1 30.7Western Europe -0.4 -0.4 21.0 -0.5 -0.2 16.6 0.4 0.4 36.0North Africa 0.4 0.3 4.1 0.0 0.2 12.3 0.6 1.7 1.8Sub-Saharan Africa 0.6 0.9 6.7 0.0 -0.1 34.7 -0.1 -0.5 27.0North America 0.1 -0.5 11.8 -0.3 -0.2 13.3 0.0 0.0 32.6Latin America and the Caribbean 1.1 0.9 7.4 0.6 0.3 30.5 -0.1 -0.3 47.0Developed countries 0.0 -0.5 11.2 -0.1 0.1 21.8 0.1 n.d. n.d.Developing countries 0.5 0.6 10.4 0.5 0.3 30.1 -0.1 n.d. n.d.World 0.3 0.1 10.8 0.3 0.2 26.6 0.0 -0.1 30.51 Data on pasture excludes Saudi Arabia.2 Data for 2000 obtained from FAO, 2005e.Note: n.d. - no data.Source: FAO (2005e; 2006b).where area expansion accounted for two-thirds multiple cropping and shorter fallow periods)of growth in production, was an exception. by higher yields, or by a combination of the two. The intensification process has been driven by Higher yields are the result of technologicala range of factors (Pingali and Heisey, 1999). In advances and higher input use in crop produc-Asia, where extraordinary growth in cereal pro- tion – notably irrigation, modern high-yieldingductivity has been achieved, rising land values plant varieties, fertilizers and mechanization.owing to increasing land scarcity have been the Use of tractors, mineral fertilizers and irriga-dominant factor. Cereal yields have also sub- tion increased strongly between 1961 and 1991,stantially increased in some Latin American and and much more slowly afterwards (see Table 1,African countries. With lower population densi- Annex 2). In comparison, use of mineral fertil-ties than in Asia, the forces influencing intensifi- izers has substantially decreased since 1991 incation have been the level of investments in mar- developed countries, as a result of more efficientket and transport infrastructure and the extent resource use and environmental regulationsto which countries engaged in export-oriented aimed at reducing nutrient loading.trade. In contrast, productivity gains were low in While scope for productivity increases stillsub-Saharan Africa, despite population growth. exists, Pingali and Heisey (1999) show that theRelative land abundance (in comparison to Asia), productivity of wheat and rice in lowland Asiapoor market infrastructure and lack of capital has lately been growing at a dwindling pace. Keycontributed to the modest performance. factors explaining this slowing trend are land Technically, increased productivity can be degradation, declining research and infrastruc-achieved by increased cropping intensity (i.e. ture investment, and increasing opportunity cost26
    • Livestock in geographic transition Figure 2.2 Total harvested area and total production for cereals and soybeans 800 700 600 Index: 1961=100 500 400 300 200 100 1961 1963 1965 1967 1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 2001 2003 Cereal harvest area Cereal production Soybean harvest area Soybean production Source: FAO (2006b).of labour, although new technological develop- development provide the broad context of landments (i.e. hybrid rice) might enable new growth. use, along with more localized factors spe-Arable land expansion will likely continue to be cific to each area. Individual and social decisionsa contributing factor in increasing agricultural leading to land changes are also increasinglyproduction. In particular, this will be the case for influenced by changing economic conditions anddeveloping countries, where arable land expan- institutional frameworks (Lambin et al., 2001).sion, increases in cropping intensity and yield Two concepts are central in explaining agri-increases accounted for 23, 6 and 71 percent, cultural land-use changes: profit per unit ofrespectively, of crop production growth over the land and opportunity cost. Profit per unit of land31961 to 1999 period, and they are expected to describes the potential interest for an operatoraccount for 21, 12, and 67 percent, respectively to engage in a particular use of the land. Profitover the 1997/99 to 2030 period (FAO, 2003a). In generally depends on the biophysical charac-developed countries, in contrast, the increase in teristics of the land, on its price, and factorsproduction is expected to be reached with a con- including accessibility to markets, inputs andstant or locally declining arable area. The fore- services. On the other hand, the opportunityseen shift to biofuels, and the increased demand cost4 compares the economic and social costsfor biomass that will result may, however, lead of two or more ways of using the same pieceto a new area of crop expansion, especially in of land. Opportunity cost includes not only theWestern Europe and North America. private costs of production, but also direct and indirect costs borne by society, such as losses2.1.2 Globalization drives national land-use changes 3 The surplus of revenue generated over expenses incurred forChanges in agricultural land use are driven by a particular period of time.a wide range of factors. Ecological conditions, 4 Opportunity cost can be defined as the cost of doing an activ-human population density and level of economic ity instead of doing something else. 27
    • Livestock’s long shadowof ecosystem services. For example, part of the the Syria Arab Republic), though they were loweropportunity cost of cropping an area would be in five (Algeria, Croatia, Morocco, Tunisia andloss of the possibility of using it for recreational Turkey) (MEA, 2005a).purposes. As economies continue to liberalize, local agri- In a context where non-marketable ecosystem cultural goods compete with equivalent goodsservices are not priced, decisions on land use are produced farther away. Increasingly, therefore,predominantly driven by calculation of private agricultural land-use opportunities are compet-profit per unit of land, usually based on tradable ing across continents. Both profit per unit of landgoods and services. As a result, the non-market- and opportunity costs of agricultural land useed benefits are often lost, or external costs are vary immensely around the globe, depending onimposed on society. However, the environmental agro-ecological conditions, access to markets,and social services provided by ecosystems are availability of production inputs (including serv-receiving increasing recognition. ices), existence of competitive land usage and A case in point is the growing recognition of the valuation of ecosystem services. Agriculturalwide range of services provided by forest, a type production relocates accordingly, resulting inof land use generally antagonistic to agricultural changes in use of agricultural land and also ofuse, although modern agroforestry technologies forests and other natural areas. For example,do produce some synergies. Forests are increas- New Zealand lamb competes with local produceingly used for conservation of biodiversity (see in Mediterranean markets. New Zealand lamb isBox 2.1). This is a global trend, although the pace produced at a relatively low cost because of muchis significantly slower in Oceania and Africa. lower opportunity cost of land (mainly owing to a Soil and water conservation is also seen as a much lower recreational demand) and higherdominant function for 9 percent of the world’s productivity of pasture. As a result, the marginalforests. Recreation and education activities are pastures traditionally used for sheep productionanother use of forest that is on the increase and in the EU Mediterranean basin are progressivelyrepresent the primary management objective for being abandoned to natural vegetation and other2.4 percent of the forest in Europe, while 72 per- recreational usages.cent of the total forest area was acknowledged to The process through which former agricul-provide social services (MEA, 2005a). tural land reverts to forest has been called the Roundwood removal, on which the calculation “forest transition”. Mainly, the term has beenof profit per unit of forest land is usually based, applied to developed countries in Europe andwas estimated at US$64 billion worldwide in North America (Mather, 1990; Walker, 1993;2005. This has been decreasing in real terms Rudel, 1998).over the last 15 years (FAO, 2005e). In a case During the early period of colonization and eco-study of the economic value of forest in eight nomic growth, settlers and farmers cleared landMediterranean countries, non-wood forest prod- rapidly to provide agricultural goods required byucts, recreation, hunting, watershed protection, local populations. Later, as urban developmentcarbon sequestration and passive use accounted came to dominate and trade expanded, ruralfor 25 to 96 percent of the total economic value populations moved to cities, and agriculturalof the forests. Non-marketed economic values markets traded with increasingly distant loca-(e.g. watershed protection, carbon sequestra- tions of demand and supply. There were hugetion, recreation, non-timber forest products) gains in agricultural productivity in areas withwere estimated higher than commonly meas- high agricultural potential.ured economic values (e.g. grazing, timber and This resulted in substantial land-use shifts:fuelwood) in three countries (Italy, Portugal and farming moved into the remaining unused fertile28
    • Livestock in geographic transitionlands, and marginal locations were abandoned, and negative effects. Increased yields in agri-especially in remote areas with poor soil charac- cultural systems help to reduce the pressure toteristics. More productive land with good acces- convert natural ecosystems into cropland, andsibility remained in production. As abandoned can even allow for re-conversion of agriculturalland reverted to natural vegetation cover, this led land back to natural areas, as observed in OECDto net reforestation in parts of Europe and North countries.America, from the end of the nineteenth century However, the increased inputs of fertilizers,on (Rudel, 1998). Forest transition is an ongoing biocides and energy that intensification involvestrend in Europe and North Africa and has shown have also increased pressure on inland-watersimilar patterns in Asia, although national poli- ecosystems, generally reduced biodiversity with-cies may have fostered the process in the latter in agricultural landscapes and generated more(Rudel, Bakes and Machinguiashi, 2002). Map 2 gaseous emissions from higher energy and min-(Annex 1) shows areas of net forest area gain in eral fertilizers inputs (MEA, 2005a). On the otherthe USA, Southern Brazil, Europe and Japan. hand, extensive use of land for pasture or crop- ping has also often led to the deterioration of2.1.3 Land degradation: a vast and vegetative cover and soil characteristics.costly loss Environmental implications of land degrada-Land degradation is widely recognized as a global tion are multiple. Among the most critical issuesproblem having implications for agronomic pro- are the erosion of biodiversity (through habitatductivity and the environment as well as effects destruction or pollution of aquifers), climateon food security and quality of life (Eswaran, Lal change (through deforestation and the loss ofand Reich, 2001). Although the magnitude of the soil organic matter releasing carbon to theproblem is broadly shared, there are a number atmosphere) and depletion of water resourcesof definitions for land degradation, interpreted (through alteration of the soil texture or remov-in different ways among various disciplinary al of vegetation cover affecting water cycles).groups. We here refer to the definition of the These mechanisms and their significance will beUnited Nations Environment Programme (UNEP) described in detail in the following chapters.where “Land degradation implies a reduction of The differences in definitions and terminol-resources potential by one or a combination of ogy for land degradation are responsible for theprocesses acting on the land, such as: (i) soil variations between results from studies thaterosion by wind and/or water, (ii) deterioration have attempted to evaluate the extent and rateof the physical, chemical and biological or eco- of this process. Oldeman (1994) produced one ofnomic properties of soil; and (iii) long-term loss the generally accepted estimates of the extent ofof natural vegetation” (UNEP, 2002). global land degradation. It estimates that about Agricultural land degradation is of particular 19.6 million km2 are degraded, mostly becauseconcern on several grounds, as it reduces pro- of water erosion (Table 2.2). This figure does not,ductivity, which in turn leads to further expan- however, include loss of natural vegetation and,sion of agricultural land into natural habitats. based on the above UNEP definition, is thereforeIt also requires additional natural resources to more an estimate of soil degradation rather thanrestore the land (e.g. lime to neutralize acidity, of land degradation. Still, according to Olde-water to flush out salinity), and can generate pol- man (1994), about one-third of the land used aslution with off-site impacts (Gretton and Salma, forests and woodlands appears to be degraded1996). Intensification and extensive land use can in Asia (ca 3.5 million km2), against 15 to 20 per-both result in environmental impacts, though in cent in Latin America and Africa. Land degra-different ways. Intensification has both positive dation of pasture is mainly an issue in Africa 29
    • Livestock’s long shadow(2.4 million km2), although Asia, and to a lesser Table 2.3extent Latin America are also affected (2.0 and Estimates of all degraded lands in dry areas1.1 million km2 respectively). Finally, about one- Continent Total Degraded Percentage area area1 degradedthird of the agricultural land is degraded in Asia (2.0 million km2), against half in Latin America, (million km2) (million km2)and two-thirds in Africa. Africa 14.326 10.458 73 Desertification is a form of land degrada- Asia 18.814 13.417 71tion, taking place in arid, semi-arid and dry Australia and the Pacific 7.012 3.759 54subhumid areas and resulting from various fac- Europe 1.456 0.943 65tors, including climatic variations and human North America 5.782 4.286 74activities (UNEP, 2002). Dregne and Chou (1994) South America 4.207 3.058 73estimated that degraded lands in dry areas Total 51.597 35.922 70of the world amount to 3.6 billion hectares or 1 Comprises land and vegetation.70 percent of the 5.2 billion hectares of the total Source: Dregne and Chou (1994).land areas considered in these regions (Table2.3). These figures include loss of vegetal coverand are not directly comparable with the previ- is estimated to reduce harvests by 36 millionous ones. Reich et al. (1999) further estimate tonnes of cereal equivalent every year, valuedthat in Africa, about 6.1 million km2 of land are at US$5 400 million, while water erosion wouldunder low to moderate degradation risk and cause losses estimated at US$1 800 million7.5 million km2 are under high and very high (FAO/UNDP/UNEP, 1994). Worldwide, it is esti-risk. Cumulatively, desertification is estimated mated that 75 billion tonnes of soil are lost everyto affect about 500 million Africans, seriously year, costing approximately US$400 billion perundermining agricultural productivity despite year, or about US$70 per person per year (Lal,good soil resources. 1998). Analysis conducted at the International Yield reduction is one of the most evident Food Policy Research Institute (IFPRI) (Scherreconomic impacts related to land degradation. and Yadav, 1996) suggest that a slight increaseIn Africa, it is estimated that past soil erosion in land degradation relative to current trendsmay have depressed yields by 2 to 40 percent, could result in 17–30 percent higher world priceswith a mean loss of 8.2 percent for the conti- for key food commodities in 2020, and increasednent (Lal, 1995). In South Asia, water erosion child malnutrition. Besides diminishing food production and food security, land degradation hampers agricultural income and thereby eco-Table 2.2 nomic growth, as shown by analysis supportedEstimates of the global extent of land degradation by country models in Nicaragua and GhanaType Light Moderate Strong Total (Scherr and Yadav, 1996). Land degradation can + ultimately result in emigration and depopula- Extreme tion of degraded areas (Requier-Desjardins and (.................... million km2 ....................) Bied-Charreton, 2006).Water erosion 3.43 5.27 2.24 10.94 Long-term effects of land degradation and, inWind erosion 2.69 2.54 0.26 5.49 particular, the reversibility of land degradationChemical degradation 0.93 1.03 0.43 2.39 processes and the resilience of ecosystems arePhysical degradation 0.44 0.27 0.12 0.83 subject to debate. Soil compaction, for example,Total 7.49 9.11 3.05 19.65 is a problem in vast areas of cropland world-Source: Oldeman (1994). wide. It is estimated to be responsible for yield30
    • Livestock in geographic transitionreductions of 25 to 50 percent in parts of the EU der resources have played an important role.and North America, with on-farm losses esti- The land area used for ruminant productionmated at US$1.2 billion per year in the United is generally substantial. Ruminants have beenStates. Compaction is also an issue in Western herded where there are pasture resources, andAfrica and Asia (Eswaran, Lal and Reich, 2001). only in exceptional cases have they been fed withSoil compaction is, however, relatively easily harvested feed (e.g. draught animals or season-reversed by adapting ploughing depth. Water ally in cold areas). Herding ruminants involvesand wind erosion, in contrast, have irreversible daily or seasonal movements, over distancesconsequences, for example mobile sand dunes varying from hundreds of metres up to hundreds(Dregne, 2002). Reversal of the land degradation of kilometres in the case of large-scale transhu-process often requires substantial investments, mance or nomadism. Some or all of the humanswhich may fall beyond investment capacity or relying on the herd are involved in the movement,do not grant satisfactory returns under cur- sometimes keeping a geographical anchor arearent economic conditions. Rehabilitation costs (e.g. village, boma, territoire d’attache).of degraded land were estimated on average at In modern times, livestock production hasUS$40/ha/year for pastures, US$400/ha/year for developed from a resource-driven activity intorainfed cropland and US$4 000/ha/year for irri- one led mainly by demand. Traditional livestockgated cropland in sub-Saharan Africa, with aver- production was based on the availability of localage investment periods of three years (Requier- feed resources, in areas where disease con-Desjardins and Bied-Charreton, 2006). straints allowed this. Modern livestock production is essentially2.1.4 Livestock and land use: driven by demand for livestock products (Del-the “geographical transition” gado et al., 1999), drawing on additional feedHistorically, people raised livestock as a means resources as required. As a result, the locationto produce food, directly as meat and dairy prod- of livestock production is undergoing importantucts and indirectly as draught power and manure shifts. With the emergence of large economiesfor crop production. Since conservation technol- such as China and India as new centres ofogy and transport facilities were poor, goods and demand and production (Steinfeld and Chilonda,services from livestock were used locally. Live- 2006) these geographic shifts have acceleratedstock were kept geographically close to human globally over the last decades. The geographysettlements, in most cases while pastoralists of livestock production and its changes are thegrazed animals on their migrations. keys to understanding livestock‑environment Distribution trends have varied according to the interactions. For example, livestock waste doestype of species. Monogastric species (e.g. pigs not pose an environmental problem in areas ofand poultry) have predominantly been closely sparse livestock density; on the contrary, it isassociated with human populations, in house- a valuable input to crop activities and helps tohold backyards. The reason is that monogastric maintain soil fertility. In contrast, in areas ofspecies depend on humans for feed (e.g. house- high livestock density, the capacity of surround-hold waste, crop by-products) and for protection ing land or waters to absorb the waste is oftenfrom predators. The distribution of human popu- exceeded and environmental damage ensues.lations and monogastric species is still closely Access to markets, feed resources, infrastruc-correlated in countries with traditional produc- ture, prices for land, labour and transport andtion systems (FAO, 2006c; Gerber et al., 2005). In disease status affect the location of livestockthe distribution of ruminant species (e.g. cattle, production. In this chapter we will analyse thebuffaloes, sheep, goats) feed and especially fod- trends in livestock geography and the underlying 31
    • Livestock’s long shadowdeterminants, to help understand and inter- over 9 billion in 2050, about 40 percent more thanpret the environmental consequences. We will today, and to begin decreasing shortly thereafterexamine first the overall extent of land devoted (UN, 2005). Population growth will combine withdirectly or indirectly to livestock production, and changes in incomes and urbanization rates tothen the geographical distribution of the main determine global trends in demand for animal-stages and types of livestock production. derived food, though the details are, of course, uncertain. In some developed countries, demandLand use intensification in the feed sector growth is already slowing or declining. In emerg-The first main feature is livestock’s demand for ing economies, the ongoing livestock revolution ispasture and cropland, and the very substantial also poised for a slow down, as the tremendouschanges in area that have occurred in the past increases in per capita livestock consumption ofand continue to occur. Grazing land has expand- the past two decades have already occurred, anded by a factor of six since 1800, and now covers population growth continues to slow.roughly 35 million km2, including large areas of In fact, growth rates of livestock productioncontinents where previously there had been little for all developing countries peaked in the 1990sor no livestock grazing (North America, South at 5 percent per year, falling to an average ofAmerica, Australia). In many areas, grazing has 3.5 percent for the 2001–2005 period. In Asiaexpanded to occupy virtually all the land that can and the Pacific, where China drove the livestockbe grazed and for which there is no other demand revolution, average annual growth rates peaked(Asner et al., 2004). South America, Southeast in the 1980s at 6.4 percent, and have decreasedAsia and Central Africa are the only parts of the since then to 6.1 percent in the 1990s and 4.1world where there are still significant areas of percent over the 2001 to 2005 period. Productionforest that could be turned into grazing, but in followed a similar pattern in West Asia and Norththe latter major investments in disease control Africa. Some regions may, however, not yet havewould be needed. As described in Section 2.5, reached their peak in production growth. Growththe expansion of pasture into forest ecosystems rates patterns are less clear in Latin Americahas dramatic environmental consequences. and may well further increase, pulled by export- More recent is the advent of grain-feeding to oriented production in countries such as Argen-livestock, starting in the 1950s in North America, tina or Brazil. Consumption and production areextending into Europe, the former Soviet Union still very low in Africa and will increase as eco-and Japan in the 1960s and 1970s, now common- nomic growth allows. Finally, production growthplace in much of East Asia, Latin America and is expected to be strong in transition countries,West Asia. Grain-feeding is not widespread yet recovering to previous levels. Despite thesein most of sub-Saharan Africa and South Asia, areas of expansion, it is probable that the bulk ofbut is rapidly increasing from a low base. This global growth in livestock production has alreadydemand for feedgrains and other feed materials occurred and that further growth will take placehas greatly increased the arable land require- at diminishing rates.ments of livestock production, from a very small At the same time, intensification and thearea to about 34 percent of the total arable land continued shift from ruminants to monogastricstoday (see Section 2.3). (especially poultry) are continuously improving Both the long-term expansion of grazing land land-use efficiency, helping to reduce the landand the more recent expansion of arable land for area used per unit of output. This is reinforcedfeed will probably reach a maximum, followed by by the effect of increased feedcrop produc-a future decrease. World population is expected tion efficiency, demonstrated by the continuingon the UN’s medium projection to grow to just yield increases in all major feedcrops described32
    • Livestock in geographic transitionabove. By reducing post-harvest losses, advanc- ronmental awareness and institutional capacityes in processing and distribution technology and permit. The same pattern applies for ruminants,practices also reduce the land required per unit but is less pronounced because their higherof consumed products. The combined effect, in daily fibre requirements entail bulk movementmany developed countries, has been a decrease of fodder, and the cost of this acts as a brake toin the extent of grazing land, amounting to, for the urbanization of livestock. Ruminant produc-example, 20 percent since 1950 in the United tion, both meat and milk, tends to be much moreStates. rural-based throughout the different phases of Two antagonist trends are thus at play: on the development, even though important exceptionsone hand production growth will further increase exist (for example, peri-urban milk production,land demand by the sector, though at dimin- such as observed in India, Pakistan and aroundishing growth rates. On the other, continuous most sub-Saharan cities).intensification will reduce the area of land used The rapid urbanization of livestock, in particu-per unit of output. The relative strength of these lar monogastrics, and the subsequent gradualtwo trends will determine the trend in total area de-urbanization is a second distinct patternused by livestock. It is suggested here that the taking place alongside the land-use intensifica-global land requirements of the livestock sector tion of the sector. Both patterns have immensewill soon reach a maximum and then decrease. implications for livestock’s impact on the envi-Grazing areas will start to decline first, fol- ronment, and constitute the basic theme oflowed by a reduction in land required for feed this and the following chapters. We will use theproduction. This overall trend is proposed as a expression “livestock transition” as a short formmodel for understanding of livestock geography for these two patterns.dynamics. 2.2 Geography of demandLocations shift in relation to markets and On a global scale, the geographical distributionfeed sources of the demand for animal-derived foods broadlyThe second major feature in livestock geography follows that of human populations (Map 3, Annexis livestock’s changing spatial distribution: the 1). However, people have quite different demandgeographical association with the feed base on patterns, depending on income and preferences.the one hand, and with people and their needs for The rationale on which people select their foodanimal products on the other. At pre-industrial is complex, based on a number of objectives,levels of development, monogastrics and rumi- and decisions are influenced by individual andnants follow different patterns of distribution. societal capacity and preferences, as well asThe distribution of monogastrics follows that of availability. Food preferences are undergoinghuman settlements. When humans live predomi- rapid changes. While growing incomes in devel-nantly in rural areas, so do monogastrics. In the oping countries are increasing the intake of pro-early phases of industrialization, occurring today teins and fats, some higher income segments inin many developing countries, humans rapidly developed countries are cutting down on theseurbanize, and so do monogastrics, usually in a components, for a number of reasons includingperi-urban belt around consumption centres. health, ethics and an altered trust in the sector.This rural to peri-urban shift creates significant On average, per capita consumption of animal-environmental problems and public health haz- derived foods is highest among high-incomeards. In a third phase, these problems are cor- groups, and growing fastest among lower- andrected by the gradual relocation of farms farther middle-income groups in countries experienc-away from cities, once living standards, envi- ing strong economic growth. The first group is 33
    • Livestock’s long shadowTable 2.4 at the expense of staple foods, such as cerealsLivestock and total dietary protein supply in 1980 and and tubers.2002 Two major features emerge from these trends. Total Total First, there is the creation of new growth poles in protein supply protein emerging economies, with Brazil, China and India from livestock supply now being global players. Meat production in the 1980 2002 1980 2002 developing countries overtook that of developed (............... g/person ...............) countries around 1996. Their share of productionSub-Saharan Africa 10.4 9.3 53.9 55.1 is projected to rise to about two-thirds by theNear East 18.2 18.1 76.3 80.5 year 2030 (FAO, 2003a). In contrast, in developedLatin America countries both production and consumption are and the Caribbean 27.5 34.1 69.8 77.0 stagnating and in some places declining. SecondAsia developing 7.0 16.2 53.4 68.9 is the development of demand hotspots – urbanIndustrialized countries 50.8 56.1 95.8 106.4 centres ‑ with high consumption per capita, fastWorld 20.0 24.3 66.9 75.3 aggregate demand growth, and a shift towardsSource: FAO (2006b). more processed animal-derived foods. A cer- tain homogenization of consumed products (e.g. chicken meat) is also observed, although localmostly concentrated in OECD countries, while cultures still have strong influence.the latter is mostly located in rapidly growingeconomies, such as Southeast Asia, the coastal 2.3 Geography of livestock resourcesprovinces of Brazil, China and parts of India. Different livestock species have the capacityThe two groups coincide geographically in urban to utilize a wide variety of vegetative material.centres in rapidly growing economies. Usually, feedstuff is differentiated into rough- Table 2.4 provides an overview of the impor- age, such as grass from pastures and crop resi-tant changes that have occurred in the average dues, and feed concentrates, such as grains orprotein intake of people in various world regions. oilseeds. Household waste and agro-industrialPeople in industrialized countries currently by-products can also represent a large share ofderive more than 40 percent of their dietary feed resources.protein intake from food of livestock origin (thefigures do not include fish and other seafood), 2.3.1 Pastures and fodderand little change has occurred between 1980 Variations in conversion, management andand 2002. Changes have been most dramatic in productivitydeveloping Asia, where total protein supply from Grasslands currently occupy around 40 percentlivestock for human diets increased by 140 per- of the total land area of the world (FAO, 2005a;cent, followed by Latin America where per capita White, Murray and Rohweder, 2000). Map 4animal protein intake rose by 32 percent. In con- (Annex 1) shows the wide distribution of pas-trast, there has been a decline in consumption tures. Except in bare areas (dry or cold deserts)in sub-Saharan Africa, reflecting economic stag- and dense forest, pastures are present to somenation and a decline in incomes. Detailed con- extent in all regions. They are dominant in Oce-sumption patterns are shown in Table 2, Annex ania (58 percent of the total area – 63 percent in2. The increasing share of livestock products in Australia), whereas their spread is relatively lim-the human diet in many developing countries is ited in West Asia and North Africa (14 percent)part of a dietary transition that has also included and South Asia (15 percent). In terms of area,a higher intake of fats, fish, vegetables and fruit, four regions have 7 million km2 of grassland34
    • Livestock in geographic transitionor more: North America, sub-Saharan Africa, duction (either temperature limited or moistureLatin America and the Caribbean and the Com- limited), which explain their low productivity inmonwealth of Independent States (see Table 3, comparison to cropland. Second, in the arid andAnnex 2). semi-arid rangelands, which form the major- As Table 2.5 shows, grasslands are increasing- ity of the world’s grassland, intensification ofly fragmented and encroached upon by cropland the areas used as pasture is often technicallyand urban areas (White et al., 2000). Agriculture and socio-economically difficult and unprofit-expansion, urbanization, industrial development, able. Most of these areas already produce atovergrazing and wildfires are the main factors their maximum potential. In addition, in muchleading to the reduction and degradation of of Africa and Asia, pastures are traditionallygrasslands that traditionally hosted extensive common property areas that, as internal grouplivestock production. The ecological effects of discipline in the management of these areasthis conversion, on ecosystems, soil structure eroded, became open access areas (see Box 2.2).and water resources, can be substantial. There Under such conditions any individual investorare, however, signs of an increasing apprecia- cannot capture the investments made and totaltion of grassland ecosystems and the services investments levels will remain below the socialthey provide, such as biodiversity conservation, optimum. Lack of infrastructure in these remoteclimate change mitigation, desertification pre- areas further contributes to the difficulty of suc-vention and recreation. cessfully improving productivity through individ- Permanent pastures are a type of human land ual investments. In extensive systems, naturaluse of grasslands, and are estimated to cover grasslands are thus only moderately managed.about 34.8 million km2, or 26 percent of the total However, where individual ownership prevailsland area (FAO, 2006b). Management of pas- or traditional management and access rules areture and harvested biomass for livestock varies operative, their use is often carefully planned,greatly. On balance, although accurate estimates adjusting grazing pressure seasonally, and mix-are difficult to make, biomass productivity of ing different livestock classes (e.g. breedingpastures is generally much lower than that of stock, young stock, milking stock, fatteningcultivated areas. A number of factors contribute stock) so as to reduce the risks of climate vari-to this trend. First, large pastures mainly occur ability. In addition, techniques such as controlledin areas with marginal conditions for crop pro- burning and bush removal are practices that canTable 2.5Estimated remaining and converted grasslands Percentage ofContinent and region Remaining Converted Converted Converted to Total in to to urban other converted grasslands croplands areas (e.g. forest)North America tallgrass prairies in the United States 9.4 71.2 18.7 0.7 90.6South America cerrado woodland and savanna in Brazil, Paraguat and Bolivia 21.0 71.0 5.0 3.0 79.0Asia Daurian Steppe in Mongolia, Russia and China 71.7 19.9 1.5 6.9 28.3Africa Central and Eastern Mopane and Miombo in United Republic of Tanzania, Rwanda, Burundi, Dem. Rep. Congo, Zambia, Botswana, Zimbabwe and Mozambique. 73.3 19.1 0.4 7.2 26.7Oceania Southwest Australian shrub lands and woodlands 56.7 37.2 1.8 4.4 43.4Source: White, Murray and Rohweder (2000). 35
    • Livestock’s long shadow Box 2.2 The complex and weakening control of access to pastureland Pastureland falls under a variety of property and maintaining such areas under a common property access rights. Three types of land tenure are gen- regime. The table below provides an overview of erally recognized, namely, private (an individual or these rules and of the relative level of security a company), communal (a local community) and they provide for the livestock keeper accessing the public (the state). Access rights can overlap with land resource. Access to water often adds another property rights, sometime resulting in a complex layer of access rights: in the dry lands, water plays set of rules controlling the use of resources. Such a critical role as location of water resources are discrepancies between access rules and the multi- determinant to the use of pastures. Consequently, plicity of institutions responsible for their applica- water rights are key to the actual access to arid and tion often lead to conflicts among stakeholders semi-arid pastureland. Holding no formal rights claiming access to pastureland. In this regard, over land, pastoralists often do not get rights over the Rural Code of Niger is an exemplar attempt water thereby suffering from a double disadvan- to secure pastoralists’ access to rangelands while tage (Hodgson, 2004). Table 2.6 Land ownership and access rights on pastoral land: possible combinations and resulting level of access security for the livestock keeper No overlapping Lease Customary Illegal intrusion or access right access rights1 uncontrolled access Private +++ 0 to ++ 0 to + Issues may arise Conflict Freehold from the conflicting overlap between customary from ++ to +++ access right and Depends on the duration recent land titling policies. of the leasing contract and the strength of the Communal +++ + to +++ + to ++ institution that guarantees Case of Customary access rights Depends on the relative the leasing contract. commonly/nationally tend to loose strength and strength of local owned herds stability because of migrations communities/public and overlap with exogenous administration and property and access right. livestock keepers Note: Level of stability in the access to the resource, from very high (+++) to very low (0) 1 Customary access rights can take numerous forms. A common trait is their indentification of first and latecomers. They are thus quite vulnerable to strong migration fluxes, in which context they may exacerbate ethnic quarrels Source: Chauveau, 2000; Médard 1998; Klopp, 2002.improve pasture productivity, although they may For the purpose of this assessment, grass-also increase soil erosion and reduce tree and lands are grouped into three categories: exten-shrub cover. The low management level of exten- sive grasslands in marginal areas, extensivesive pasture is a major reason why such grass- grasslands in high potential areas, and intensivelands can provide a high level of environmental pastures.services such as biodiversity conservation.36
    • Livestock in geographic transition Box 2.2 (cont.) Stability and security in accessing the pastoral While detailed statistics are lacking, it is prob- resource are of utmost importance, as they are ably safe to say that most pasture land is private determinant to the management strategy the user property, not common property and government will adopt. In particular, investments in practices land. Pasture are predominantly established on and infrastructures improving pasture productivity communal and public land in Africa (e.g. freehold may only be implemented if there is a sufficiently land covers only about 5 percent of the land area in high probability to realize economic returns on the Botswana), South Asia (e.g. Commons, dominantly mid to long term. More recently, the existence of under pasture, account for around 20 percent of clear usage rights has shown to be indispensable India’s total land area), West Asia, China as well as to the attribution and remuneration of environmen- Central Asia and Andean highlands. Furthermore, tal services. in Australia, most of the Crown Land ‑ representing about 50 percent of the countries’ area ‑ is grazed Table 2.7 under leases. In contrast, the majority of pasture Land use and land ownership in the United States land is titled under private ownership in Latin Acre Cropland Pasture Forest Other Total America and in the United States. Indeed, a survey on the United States shows that 63 percent of pas- Federal 0 146 249 256 651 tures are privately owned, while 25 percent belong State and local 3 41 78 73 195 to the Federal State and the rest to states and local Indian 2 33 13 5 53 communities (see Table 2.7). Finally, in Europe, Private 455 371 397 141 1 364 pasture located in fertile low lands are gener- Total 460 591 737 475 2 263 ally privately owned, while marginal areas such Relative percentages as mountain rangelands and wetlands are usu- Federal 0 25 34 54 29 ally public or communal, with traditional access State and local 1 7 11 15 9 rights. Indian 0 6 2 1 2 Private 99 63 54 30 60 Source: Anderson and Magleby (1997). Extensive pasture in marginal areas are potential are generally used in more intensivedefined here as having a net primary productiv- forms than pasture. Grasslands in marginality of less than 1 200 grams of carbon per m2/yr areas are used extensively, either by mobile pro-(Map 4, Annex 1; Table 4, Annex 2). This is the duction systems (Africa, the CIS, South Asia andlargest category by area (60 percent of all pas- East Asia), or in large ranches (Oceania, Northtures), and is located mostly in dry lands and cold America). Using actual evapotranspiration (AET)lands. This category is particularly dominant in as an indicator of vegetation climatic stress,developed countries, where it represents almost Asner et al. (2004) show that in dry land biomes80 percent of grasslands, while in developing grazing systems tend to occupy the driest andcountries it accounts for just under 50 percent of climatologically most unstable regions, and inpastures. The contrast can be explained by dif- temperate biomes the most humid and/or coldferences in the opportunity cost of land: in devel- parts. In terms of soils, the authors also showoped countries, areas with good agro-ecological that grazing systems generally occupy the least 37
    • Livestock’s long shadowfertile soils in the dry lands and the unfrozen demand for feed and the inability of traditionalsoils of the boreal areas, along with both least feed resources to supply the quantities and qual-fertile and moderately fertile soils in the tropical ities required. The growing demand for food andbiomes. They conclude that the land frontier for feed has been met without an increase in prices.further pasture expansion into marginal areas is On the contrary, it was driven by a decrease inexhausted. cereal prices. In real terms (at constant US$) Extensive pasture in high potential areas is international prices for grains have halved sincedefined as those with a net primary productivity 1961 (FAO, 2006b). Expanding supply at decliningof more than 1 200 g of carbon per m2/y (Map 4, prices has been brought about mainly by intensi-Annex 1; Table 4, Annex 2). Pastures in this cat- fication of the existing cropped area.egory are predominantly found in tropical humidand subhumid climates, as well as in parts of CerealsWestern Europe and the United States. Because Expansion of feed use slows as feed conversionbiomass production is steady or seasonal, such improvespastures are predominantly fenced in and grazed Some 670 million tonnes of cereals were fed tothroughout the year. livestock in 2002, representing a cropped area of Intensive cultivated pasture production is around 211 million hectares. A variety of cerealsfound where climatic, economic and institutional are used as feed, mostly for monogastric speciesconditions are favourable, and land is scarce. including pigs and poultry. For ruminants, cere-Such conditions are typically found in the EU, als are usually used as a feed supplement. How-North America, Japan and the Republic of Korea. ever, in the case of intensive production, such asIn the EU, meat and dairy production units rely feedlot or dairy production, they can representto a large extent on temporary pastures (leys), the bulk of the feed basket.and on the cultivation of forage crops for fresh Worldwide, the use of cereal as feed grewand conserved feed. The most intensive pastures faster than total meat production until the mid-are found in southern England, Belgium, the 1980s. This trend was related to the intensifica-Netherlands and parts of France and Germany. tion of the livestock sector in OECD countries,Forage systems are high-yield oriented, with and the related increase in cereal-based animalregular use of high levels of mineral fertiliz- feeding. During this period, the increasing shareers combined with regular manure applications of cereals in the feed basket raised the meat pro-and mechanization. These intensively used pas- duction. After this period, meat production hastures are a main source of nutrient loading and grown faster than cereal use as feed. This can benitrate pollution in those countries. Cultivated explained by increasing feed conversion ratiosgrasslands are usually species-poor and are achieved by a shift towards monogastric species,typically dominated by Lolium species (European the intensification of livestock production basedCommission, 2004). Intensive forage production on high-yielding breeds and improved manage-in some cases supplies processing industries, ment practices. In addition, the reduction of sub-such as alfalfa dehydration and hay compac- sidies to cereal production under the EU Com-tion. These industries (mostly in Canada and the mon Agricultural Policy and economic regressionUnited States) are highly export-oriented. in the ex-socialist countries of Central Europe have reduced the demand for feed grains.2.3.2 Feedcrops and crop residues In developing countries, increased meatThe feed use of primary food crop products such production has been coupled with increasingas cereals and pulses has increased rapidly use of cereals for feed over the whole periodover recent decades, responding to the growing (Figure 2.3). Recently, though, demand for cereal38
    • Livestock in geographic transition Figure 2.3 Comparative growth rates for production of selected animal products and feed grain use in developing countries 1 700 1 500 1 300 1 100 Index: 1961=100 900 700 500 300 100 1961 1966 1971 1976 1981 1986 1991 1996 2001 Cereals used as feed Total meat production Total pig and poultry meat production Total ruminant meat production Total milk production Source: FAO (2006b). Figure 2.4 Regional trends Overall, since the late 1980s, feed demand for in the use of feed grains cereal has been relatively stable. Such stability, 450 observed at an aggregated level, hides a marked 400 geographical shift in demand, which occurred in 350 the mid-1990s. Demand in the transition coun- Million tonnes 300 tries fell sharply, offset by increases in demand 250 from Asian developing countries (Figure 2.4). 200 At the same time, but more progressively, feed 150 demand dwindled in industrialized countries and strengthened in the developing world. 100 Expressed as a share of total cereal produc- 50 tion, volumes of cereal used as feed increased 0 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 substantially in the 1960s, but remained fairly Africa developing Asia developing stable thereafter and even declined in the late Latin America and the Caribbean Developed countries 1990s. Transition markets Among the cereals, maize and barley are used Source: FAO (2006b). mainly as feed – more than 60 percent of their total production over the 1961 to 2001 period. However, feed demand for cereals varies greatlyas feed has tended to stabilize, while total across regions. Maize is the predominant feedmeat production has continued to grow, prob- cereal in Brazil and the United States, whileably driven by highly intensive and monogastric- wheat and barley are dominant in Canada anddominated developing countries, such as Brazil, Europe. Southeast Asia relied on similar propor-China and Thailand. tions of wheat until the early 1990s, since then, 39
    • Livestock’s long shadow Figure 2.5 Feed demand for maize and wheat in selected regions and countries from 1961 to 2002 Maize 250 000 200 000 Thousand tonnes 150 000 100 000 50 000 0 1961 1971 1981 1991 2001 Wheat 140 000 120 000 100 000 Thousand tonnes 80 000 60 000 40 000 20 000 0 1961 1971 1981 1991 2001 East Asia EU25 China India Sub-Saharan Africa Latin America Brazil USA Source: FAO (2006b).has progressively shifted to maize. These trends translate into different feed rations at the live-reflect the suitability for production of particular stock production level. There is a remarkablecrops in these regions – wheat and barley being homogeneity in the total cereal component inmore adapted to temperate or cold climates than feed rations across analysed countries (cerealsmaize (Map 5, Map 6 and Map 7, Annex 1). represent for example about 60 percent of the Different comparative advantages for pro- weight of chicken feed – Figure 2.6). However,ducing feedgrains, along with trade conditions, countries differ noticeably in the mix of various40
    • Livestock in geographic transition Figure 2.6 Relative composition of chicken feed ration in selected countries (by weight) 100 90 80 70 60 Percentage 50 40 30 20 10 0 USA Canada Mexico Brazil Belgium France Germany Italy Netherlands UK Thailand China Japan Maize Sorghum Peas Wheat Soymeal Fish meal Barley Other oilseed meal Other Note: A large amount of rice is included in the “other” class for Thailand. Source: Own calculations.cereals. Maize dominates in chicken feed in Bra- dues into valuable food and non-food goods andzil, China and the United States and wheat in the services. Crop residues represent a large shareEU. Similar trends are observed for pigs, with a in the feed basket, especially in tropical semi-more variable cereal content (60 to 80 percent) arid and subhumid environments where mostfor the analysed countries (Figure 2.7). of the world’s poor farmers live (Lenné, Fernan- dez-Rivera and Bümmel, 2003). Crop residuesCrop residues – as well as agro-industrial by-products – oftenA valuable but increasingly neglected resource play a critical role during periods when pasturesCrop residues are a by-product of crop agricul- are in low supply (Rihani, 2005). Devendra andture. They are typically high in fibre content but Sevilla (2002) estimated that 672 million tonneslow in other components and indigestibility. The of cereal straws and 67 million tonnes of otherrole of crop residues is, therefore, usually one of crop residues are potentially available as feed insupplementing basic caloric and fibre require- Asia. The actual use of rice straw as feed variesments, mostly in the diet of ruminants. The use greatly, from over 70 percent of the availableof crop residues such as straw and stover as feed total in Bangladesh and Thailand to only 15 per-is still fundamental to farming systems that pro- cent in South Korea. In other countries of South-duce both crops and livestock. In these systems, east Asia and in China, the share is estimated atlivestock (particularly ruminants) convert resi- between 25 and 30 percent. 41
    • Livestock’s long shadow Figure 2.7 Relative composition of pig feed basket in selected countries (by weight) 100 90 80 70 60 Percentage 50 40 30 20 10 0 USA Canada Mexico Brazil Belgium France Germany Italy Netherlands UK Thailand China Japan Maize Sorghum Soymeal Fish meal Wheat Rice Rapeseed meal Other Barley Rye Peas Note: A large amount of oats is included in the “other” class for Italy. Source: Own calculations. Despite its local importance in smallholder Other feedcropsmixed farming systems, the use of crop residues After cereals, the second main category of feed-as feed is in decline. A number of factors drive crop is roots and vegetables. About 45 millionthis trend, all are related to agricultural inten- tonnes were fed to livestock in 2001 ‑ mostlysification. First, less crop residues are available cassava, potatoes, sweet potatoes, cabbage andper unit of crop produced, because of genetic plantain. In addition, about 17 million tonnesselection aimed at reducing residues (e.g. dwarf of pulses (mainly peas and beans) were fed tocereals) and because of more effective harvest- livestock, representing an important share ofing machinery. Second, genetic selection, based protein intake in some places, e.g. France, Italyon performance traits relating to the main food and the Netherlands. Pulse, root and vegetableproduct, tends to reduce the quality of crop feedcrops are estimated to span a total arearesidues (Lenné, Fernandez-Rivera and Büm- of over 22 million hectares. Oil seeds can alsomel, 2003). Third, intensive livestock production directly be fed to livestock, although the largerequires feed of high quality, which typically can- majority is processed and only by-products arenot be provided by crop residues. In addition, crop used as feed. In 2001, feed demand for oil seedsresidues have gained increasing importance as a totalled about 14 million tonnes, equivalent to asource of energy and in furniture production. cropped area of 6.4 million hectares. The main oil seeds used as feed include soybeans, cotton- seed, rapeseed and sunflower seed.42
    • Livestock in geographic transition2.3.3 Agro-industrial by-products species. Part of this increase in use of soymealAs humans develop ever more sophisticated food by livestock is a consequence of the increasingchains, agro-industries are growing and so is the demand for fishmeal in the fast expanding aqua-availability of associated by-products as sources culture sector, which, with a rather inflexibleof animal feed. An increasing share of human supply of fishmeal, forced the livestock sectorfood is being processed, the number of stages to search for other protein substitutes in live-of processing is growing, and processing plants stock feed. Aquaculture is more dependent onare scaling up. All these factors raise the avail- fishmeal (and fish oil) than terrestrial animals,able amounts of by-products of reliable quality, and the share of fishmeal used by aquacultureso that gathering and processing them as feed grew from 8 percent in 1988 to about 35 percentbecomes economically profitable. in 2000 (Delgado et al., 2003) and 45 percent in 2005 (World Bank, 2005a) despite efforts toSoybean reduce the proportion of such products in theFeed demand drives a production boom fish feed ration. Another factor is the prohibitionSoymeal, a by-product of the soybean oil indus- of using animal offal in animal feed to reduce thetry, is a case in point. In oil extraction, soybeans risk of mad-cow disease, which put more pres-yield 18 to 19 percent oil and 73 to 74 percent sure on the production of vegetable protein formeal (Schnittker, 1997); the rest is waste. Only a animal feed (see 2.3.4).small portion of the harvested beans is directly World soybean production tripled over thefed to animals (about 3 percent globally). How- 1984 to 2004 period, half of this increase occur-ever, more than 97 percent of the soymeal ring in the last five years. Production is highlyproduced globally is fed to livestock. Soymeal concentrated geographically. Eight countriesis used primarily in the diet of monogastric provide 97 percent of world production; the topspecies, particularly chickens and to a lesser three countries (Argentina, Brazil and the Unitedextent pigs. Figure 2.8 shows the high frac- States), account for 39 percent, 26 percent andtion of soybeans processed by the oil industry, 17 percent respectively. These three countriesand the stable ratio between processed beans also achieved the highest absolute growth inand resulting cakes over the last four decades. production over the past four decades.Worldwide, the feed demand for soymeal has Map 9 (Annex 1) provides an overview of areasskyrocketed over the past four decades, reaching where soybean is cropped for oil and meal130 million tonnes in 2002 – see Figure 2.8. This production. The strong geographical concentra-far outstrips the second largest oilcake, made of tion is clearly visible. Soybean processing andrape and mustard seed, with 20.4 million tonnes marketing have a high level of geographicalof production in 2002. concentration, specialization, vertical integra- Growth of soymeal feed production took off tion and economies of scale. Small producersin the mid-1970s and accelerated in the early – especially in developing countries – find it very1990s, propelled by rapidly growing demand in difficult to compete, especially when faced withdeveloping countries. However, soymeal use per the requirements of rapidly expanding and highlyperson is much higher in developed countries efficient international trade. Recently, however,(50 kg per capita as opposed to 9 kg in devel- new countries started producing soybeans foroping countries). Over the past four decades, export, achieving substantial production growthdemand for soymeal has increased faster than over the 1999 to 2004 period. These countriestotal meat production, implying a net increase are in Latin American (e.g. Bolivia, Ecuador,in the use of soymeal per unit of meat produced. Uruguay), the former Soviet bloc countries (e.g.This is true for ruminant as well as monogastric Czech Republic, Kyrgyzstan, the Russian Federa- 43
    • Livestock’s long shadowtion and Ukraine) and Africa (e.g. Uganda). Of the ysis of feed baskets (Figures 2.6 and 2.7), whichlargest soybean producers, the United States shows that soymeal is a major source of proteinhas the highest average yields: 2.6 tonnes per in all countries analysed. The contribution ofhectare. other locally produced vegetable protein sources Some of the smaller producers also achieve such as peas and other oil cakes is generallygood results. Argentina and Brazil produce on limited. The increasing demand for oilseeds foraverage about 2.4 tonnes/ha, while China’s yields biofuels might change these trends (see 2.3.4).are only 1.65 tonnes/ha. India is far behind withaverage yields of only 0.90 tonnes/ha (Schnittker, Other agro-industrial by-products1997). Over the past decade, the yield increase Other agro-industrial by-products are less wide-has been substantial, although most of the ly commercialized and their use is confinedextraordinary growth in supply was the result to their regions of origin. They are often usedof expansion of soybean harvested area – see during droughts or other periods of scarce feedFigure 2.2. Although the soy oil industry was supply to supplement pasture and crop residuesinitially the main driver of soybean production, (Rihani, 2005). In North Africa, their contribu-feed demand is currently driving the expansion. tion to feed resources for small ruminants risesIndeed, soymeal accounted for about two-thirds from 10 percent in favourable years to 23 percentof the value of soybeans in recent years, with oil in years with drought, when pasture and cropabout one-third. This situation has developed residues are short (Rihani, 2005). In this region,over the past 30 to 40 years, as the demand agro-industrial byproducts used for feed includefor protein for terrestrial and aquatic animal brewery residues, citrus, tomato and date pulp,feed increased rapidly and as the production of olive cakes, and sugarbeet molasses and pulp.other oil-rich seeds such as palm oil, canola In Japan, 30 percent of agro-industrial byprod-and sunflower weakened the demand for soy oil ucts are recycled as feed after being dehydrated(Schnittker, 1997). This is confirmed by the anal- (Kawashima, 2006). In contrast, food wastes from marketing and retailing are much less recycled as feed (5 to 9 Figure 2.8 Global trends in demand for soybean percent, depending on the source), because their and soybean cake from 1961 to 2002 content and quality vary greatly and their geo- graphical spread increases collection costs. The 200 safety of food wastes is also questionable. 180 160 Household waste 140 Million tonnes 120 The use of household waste as feed remains pre- 100 dominant among rural households in developing 80 countries; though in OECD countries it is only 60 sporadic. Food wastes are often collected from 40 food processors in urban centres. Food wastes 20 from individual households have been an impor- 0 1961 1966 1971 1976 1981 1986 1991 1996 2001 tant traditional feed resource, in particular for Soybean cake feed demand smallholder monogastric and dairy production. Soybean processed for oil/cakes Total soybean demand Indeed, the recycling of household wastes, as feed for monogastric species, explains the close Source: FAO (2006b). spatial correlation between human populations and those of pigs and poultry prior to and during44
    • Livestock in geographic transitionTable 2.8 the 1997/99 to 2030 period (at growth rates ofSupply and recycling of food by-products in Japan 1.9 percent a year between 1997/99 and 2015, Supply Share Share and 1.6 percent per annum thereafter). Most of of recycle recycle this growth will be driven by developing coun- by-products as in per feed other tries, where the use of concentrate feeds is year forms projected to grow faster than meat production. (thousand tonnes) (%) (%) Feed use is expected to remain the most dynam-Food manufacturing industry 4 870 30 48 ic element driving the world cereal economy,Food wholesaler/retailer 3 360 9 26 accounting for a growing share of aggregateFood service industry 3 120 5 14 demand. Use of maize as feed is projected to riseTotal 11 350 17 32 from 625 to 964 million tonnes over the 2002 toSource: Kawashima (2006). 2030 period, with most of the growth occurring in developing countries (265 million tonnes), especially in Southeast Asia (133 million tonnes),the early stages of industrialization. However, Latin America (56 million tonnes) and to a lesserrising environmental and human health require- extent in sub-Saharan Africa (33 million tonnes).ments usually bring an end to backyard produc- Projected feedcrop growth rates are higher thantion in urban and peri-urban areas, once rural over the last 15 years. The projected increasingareas are connected to urban centres adequately feed demand for cereals is the result of interact-enough to provide sufficient and reliable sup- ing trends.plies. First, the current recovery of economic decline in transition economies is expected to be sus-2.3.4 Future trends tained, and with it the growing demand for live-Increasing feed demand stock products. Such demand will fuel produc-Today, feed production is estimated to use tion and thus feed demand to levels at leastapproximately 30 percent of the emerged land. equal to those observed in the early 1990s. FeedStatistics on pasture add up to 34.8 million km2 demand for cereals is also expected to rise inglobally (26 percent of emerged land) while we the EU, boosted by decreasing prices inducedestimate that about 4.7 million km2 of crop- by the common agricultural policy (CAP) reformland are currently dedicated to feed production process. The reforms proposed in 1992, and(4 percent of emerged land or 33 percent of implemented in 1994 (Ray MacSharry reform),all cropland). The latter does not include crop brought a 30 percent cut in the cereal interven-residues but includes most agro-industrial by- tion price, phased in over three years. Theseproducts (see methodological note in Annex 3). were followed by a further reduction in sup-In comparison, the shares of total meat output port prices for cereals, which were agreed to infrom grazing, mixed and intensive landless, March 1999 in the framework of Agenda 2000. Inare estimated at 8 percent, 46 percent and 45 parallel, factors reducing demand are expectedpercent respectively (see Section 2.4). The jux- to weaken. Especially, the gain in feed efficiencytaposition of these figures gives a sense of the is expected to dwindle.strong intensity gradient along which livestock In the past decades, the shift towards mono-use land. gastric species, especially poultry, which has Livestock production is projected to increase a higher feed conversion ratio than ruminantsand with it the demand for animal feed. FAO (typically 2 to 4 versus 7 kg of grain per kilogram(2003a) estimates that feed demand for grain of meat) (Rosegrant, Leach and Gerpucio, 1999);will increase by nearly one billion tonnes over further gains in feed efficiency, from advanced 45
    • Livestock’s long shadow feeding methods (multiple-stage feeding) and Although possible, a significant shift to fish prod- breeding, have allowed a substantial increase ucts would, however, require both the organiza- in feed efficiency, which has contributed to the tion of supply chains and changes in consumers’ counterbalancing of the soaring demand for preference and would thus probably only occur feed. However, it is estimated that the shift over a long period. towards monogastric species will be slower than Although at a slower pace, the number of over the last 20 years (FAO, 2003a) and room for grazing animals will also increase, requiring feeding and breeding improvement also seems more fodder. Tilman et al. (2001) estimate a net limited. increase of 2 million km2 of pasture by 2020 and The role aquaculture will play in this process of 5.4 million km2 by 2050. While recognizing that is uncertain. Products from fish fed on similar pasture expansion will probably occur in Latin feed as livestock (e.g. tilapia) may be increas- America and, to a lesser extent, sub-Saharan ingly substituted for livestock products. Because Africa, the authors of the current study consider of their substantially better feed conversion ratio that these figures may be overestimated. than livestock5 (typically 1.6 to 1.8 for tilapia), The potential and actual production of vegeta- aquaculture may play the role poultry played in tive feed resources varies substantially across the past, depressing feed demand for cereals. the globe along with different ecological, eco- nomic, technical and policy contexts. The ques- tion of how feed supply can meet the demand 5 Fish are cold-blooded, use less energy to perform vital func- of a burgeoning livestock sector is of relevance tions and do not require the heavy bone structure and energy to move on land. Fish catabolism and reproduction is also beyond its boundaries. Some aspects of this more efficient. question are assessed below.© FAO/5748/P. Vaughan-Whitehead Mixed cattle at pasture on a ranch in Obala – Cameroon 1969 46
    • Livestock in geographic transitionPastures: backs against the wall and conflicts between pastoralists and agricul-Exploring options for pasture expansion, Asner turalists.et al. (2004) suggest that the expansion of graz- Pastures are on the increase in Africa anding systems into marginal areas has already in Latin America where the land colonizationmore or less reached the limits imposed by process is still ongoing. The pace of pastureclimate and soil factors. Any significant increase expansion into forests will depend mainly onof grassland could, therefore, only take place in macro- and microlevel policies in concernedareas with high agro-ecological potential. areas. In OECD countries, the total pasture area To see what land-use changes might result will be stable or declining, as rangelands arefrom pasture expansion, the current dominant converted to cropland, urban areas and naturalland use in areas with high suitability for pasture ecosystems/recreational areas. Since the pros-but no current use as pasture are identified (see pect of expansion on pastureland is limited, theMap 10, Annex 1). Globally, forestry is the pre- intensification of pasture production on the mostdominant current use of this land (nearly 70 per- suitable land, and loss of marginal pastures,cent) and in most of the continents, especially is likely to continue (Asner et al., 2004). It isin sub-Saharan Africa (88 percent) and Latin indeed estimated that there is significant scopeAmerica (87 percent). Cropland is the leading for increased grassland production, throughcurrent use in West Asia and North Africa, East- improved pastures and enhanced management.ern Europe and South Asia. Urbanization is of In the subhumid areas of Africa, and especiallylocal relevance only, except in Western Europe, in West Africa, Sumberg (2003) suggests that,where urban areas occupy 11 percent of the land on fertile soils with good accessibility, cropssuitable for pasture. and livestock will be integrated, while the most These results suggest that any significant remote areas will be progressively marginalizedincrease of grassland into areas with high agro- or even abandoned.ecological potential can, therefore, only occur Climate change is also likely to alter grass-at the expenses of cropland (which is highly land-based systems. The impact on naturalimprobable) or through the conversion of for- grasslands will be greater than on cropland,ests to pasture, as is currently happening in the where growing conditions can be more easilyhumid tropics. manipulated (e.g. by irrigation or wind protec- In reality, pasture will most probably keep on tion). On dry lands, the impact is projected to belosing ground to cropland. This trend is already dramatic. Results from a case study in Mali byoccurring in a number of places, and in par- Butt et al. (2004) indicate that climate changeticular in Asia and sub-Saharan Africa, fuelled could reduce forage yields by as much as 16 toby an increasing demand for grain. Urbanized 25 percent by 2030, while crop yields would beareas will also encroach into pasture land, less affected, with a maximum of 9 to 17 percentespecially in areas with booming populations reduction for sorghum. In contrast, pasturessuch as sub-Saharan Africa and Latin America. located in cold areas are expected to benefit fromEncroachment by urban and cropland areas is rising temperatures (FAO, 2006c). An opportu-particularly harmful to pasture-based systems, nity for pasture expansion exists in transitionas it usually takes away the most productive countries, where extensive areas of abandonedland. This compromises the access to biomass grassland would be available for re-colonizationduring the dry season, when the less productive at relatively limited environmental cost.land cannot sustain the herd. This often resultsin overgrazing, increased losses during drought 47
    • Livestock’s long shadowCroplands production, and its consequences in terms ofProspects for yield and land expansion jeopardized ecological damage and decreased productiv-by degradation and climate change ity. Declining productivity trends observed latelyProducing more feed will require increasing in South Asia can be directly linked to theproductivity, increasing production area, or a ecological consequences of intensive cropping,combination of both. There is a wide consensus including the build-up of salinity, waterlogging,that the potential to further raise the yield fron- declining soil fertility, increased soil toxicity andtier in cereals and oilseeds is generally large; increased pest populations (Pingali and Heisey,although yields may have peaked in some areas 1999). Expanding arable land into natural eco-(e.g. the Ganges basin) (Pingali and Heisey, 1999; systems also has dramatic ecological impli-FAO, 2003a). In the case of major cereals, the cations, including loss of biodiversity and ofyield frontier of maize would be easiest to shift, ecosystem services such as water regulationthrough technology transfer from industrialized and erosion control. Issues of land degradationnations. Pingali and Heisey (1999) estimate that associated with intensive agriculture are furtherthis transfer is most likely to occur in China investigated in Section 2.5 below.or other parts of Asia, where rapidly expand- Second, although there seems to be enoughing demand for feed maize will make the crop production potential for the world taken as aincreasingly profitable and where the private sec- whole, there are considerable local variations.tor should be able to make the necessary invest- Because of land scarcity and poor land suit-ments. In contrast, growth in soybean yields may ability for cropping, local level land shortagesbe slower (Purdue University, 2006). There is also are likely to arise (FAO, 2003a). The impact ofremaining potential for expansion of cropland. climate change will also vary considerably byCurrently, arable land plus land under perma- region. Climate change will affect the yields ofnent crops is estimated to represent slightly over vegetative resources for livestock production,one-third of the land that is suitable for crop pro- mainly through changes in temperature, rain-duction (FAO, 2003a). It is, therefore, estimated fall, CO2 concentration, ultraviolet radiation andthat land expansion will continue to contribute to pest distribution. Indirect effects may also occurthe growth of primary agricultural output. through the alteration of soil biology and chem- The prospects vary considerably by region. The istry. Some of these changes will be damaging,possibility of expanding cropland under grains such as reduced yields in many areas; someand soybean is limited in South and South- may be beneficial, such as the “fertilizing effect”east Asia (Pingali and Heisey, 1999). It is more of increased CO2 concentrations. The literaturepromising in most other continents, especially tends to agree that there may be a net reductionin Africa and Latin America. The contribution of of yields aggregated at global level. However,arable land expansion to crop production over the North America, South America, Western Europe1997/99 to 2030 period is projected to be 33 per- and Oceania are often listed among the regionscent in Latin America and the Caribbean, 27 for which climate change may bring increasingpercent in sub-Saharan Africa, 6 percent in South yields (Parry et al., 2004).Asia and 5 percent in East Asia (FAO, 2003a).These figures reflect the extent of areas with high Competitions and complementarities in the questpotential for cereal production (Map 11, Annex 1), for feed biomassand soybean production (Map 12, Annex 1). Animals are not the sole users of crops, crop Two major issues jeopardize this overall wastes and by-products. The foodcrop, aquacul-positive picture. First is the land degradation ture, forestry and energy sectors are competingassociated with intensifying and expanding crop users, thus indirectly competing with livestock48
    • Livestock in geographic transitionfor land resources. Direct competition between total area used for biofuel crop production in thefeed and food demand for cereal is estimated to EU was around 1.8 million hectares (EU, 2006).be low on average. The elasticity of the livestock The average ethanol yield ranges between 3 000demand for cereals and oilseeds is much higher litres/ha (based on maize) and 7 000 litres/hathan elasticity of the human demand. Thus, when (beet) (Berg, 2004). In the medium to long term,crop prices rise, the demand for meat, milk and this land use may well compete with feed pro-eggs tends to decrease rapidly, releasing more duction. It is, however, foreseen that the “secondof the cereal supply to human consumption. It generation” of bio-fuels will rely on a differentcan, therefore, be argued that the use of cereals biomass resource, shifting to the fermentationby livestock represents a buffer, acting to protect of lingo-cellulosic materials. If such prospectsfood demand from fluctuations in production materialize, the biofuel sector may well become(Speedy, 2003). This buffering effect occurs also a strong competitor of the grass-based livestockon a smaller scale, for example with sheep fat- production for the access to biomass.tening in the Sahel. In a good year, the surplus Complementarities also exist. The potentialgrain crop is used for the household fattening complementarities between food and feed pro-of sheep, whereas in a bad year, it is exclusively duction at the level of crop residues and agro-used for human food. But the availability of using industrial by-products are well known and tograin for animal feed in good years induces some extent achieved (e.g. oilseed meal). Thefarmers to grow more than strictly needed, thus further expansion of agro-industrial by-prod-improving food security in a poor year. ucts and non-conventional feed resources may FAO projections suggest that, despite region- represent a major potential for increasing feedally contrasted trends, the share of cereals glob- resources from primary crop production.ally used as feed is likely to increase by 2030, In contrast, food wastes are seldom recycleddriving cereal production growth from 1.8 to 2.6 as feed. With a very low self-sufficiency for feedbillion tonnes between 1999/01 and 2030. An (24 percent), Japan is exploring ways of increas-increasing share of this feed use will be taken ing recycling of food waste for feed. In addition toby the aquaculture industry, which is expected reducing feedstuff imports, the aim is to reduceto grow at 4 to 6 percent per year to 2015, and 2 environmental impacts currently associated withto 4  percent per year over the following 15 years incineration or dumping in landfills. Kawashima(FAO, 1997). (2006) proposes technical options for the sanita- Indeed, with feed conversion ratios better than tion and homogenization of food wastes, basedthose for livestock, aquaculture will become a on dehydration, heat treatment and silage.significant competitor to monogastric species in In various contexts, food wastes and agroregions such as Southeast Asia and sub-Saharan industrial by-products could contribute substan-Africa. tially to the feed supply, and by the same token The energy sector is another competitor. With release pressure on land. Their better recyclingthe approaching depletion of fossil fuel resourc- can help to improve self-sufficiency for feed andes and increasing efforts to mitigate climate to improve animal productivity by supplement-change, green energies based on vegetal bio- ing diets. There is also an ecological interest inmass are taking off. Today, ethanol produced recycling the nutrients and energy embodied infrom sugar cane accounts for 40 percent of the food wastes and by-products, instead of dispos-fuel sold in Brazil. Worldwide, fuel ethanol pro- ing of them in environmentally damaging ways.duction increased from 20 billion litres in 2000 to However, food safety and ethical concerns do40 billion litres in 2005, and is expected to reach limit the potential for this practice, and must be65 billion litres in 2010 (Berg, 2004,) In 2005, the adequately addressed. 49
    • Livestock’s long shadowFood safety and consumer preferences also shift concern about genetically modified organismsfeed requirements (GMOs). Responding to consumer concerns, theThe bovine spongiform encephalopathy (BSE) EU has required that products containing GMOsscare has shown the dramatic consequences be labelled so that consumers can identify them.of an ill-considered recycling of agro-industrial In addition, the EU is pushing for GMO soybeansby-products (in this case meat and bone meal) to be separated from other varieties, so thatas animal feed. The incident and its media cov- those purchasing them for feed or as ingredientserage have also brought new livestock feeding can make a choice. This trend, if maintained, willpractices to general public attention. This and impact producers’ relative competitiveness assimilar events such as dioxin contamination of well as production practices. More generally, thebroiler meat in some EU countries have created use or banning of GMOs in animal feeds will havewidespread consumer distrust in the industrial an impact on the crop species used, produc-livestock sector. Following the precautionary tion practices, competitiveness of smallholders,principle (UN, 1992), the EU set a ban on feeding yields and the future geographical distribution ofmeat-and-bone meal to all farm animals start- their production areas.ing on 1 January 2001. While the adoption of the precautionary prin- 2.4 Production systems: locationciple should guarantee safer animal-derived economics at playfoods, it may have a significant impact on feed Production and processing systems are shapedrequirements. The EU meat-and-bone meal ban by the requirements of linking demand withis a dramatic example. Before the ban the resources (feed, labour, water, etc.), givenamount of meat and bone meal consumed in the available technology and capital. This hasthe EU was about 2.5 million tonnes annually. resulted in the diverse geographical trends ofBased on protein equivalency, this equates to livestock and production systems that we cur-2.9 million tonnes of soymeal or to 3.7 million rently observe. The pattern has changed overtonnes of soybeans (USDA/FAS, 2000). Large- time, following human population dynamics (e.g.ly because of the ban, EU soymeal imports growth, movements), technical changes (e.g.increased by almost 3 million tonnes between domestication, cropping, transport) and cultural2001 and 2003, about 50 percent more than over preferences.the previous period of the same length. Soybean These geographical shifts are still continu-expansion and shipment creates environmental ing, perhaps even accelerating, as a result ofimpacts in terms of biodiversity erosion, pollu- the rapid evolution driven by demand, resourcetion and greenhouse gas emissions (see Chapter scarcity, technology and global trade (see Chap-3). Although soymeal is the main beneficiary of ter 1). The major changes in demand for animalthe meat-and-bone meal ban, corn gluten, field products were reviewed in Section 2.2. Theypeas, rapeseed meal and sunflower seed meal have resulted in a geographical redistribution ofare other potential substitutes. This example demand, with urban centres in rapidly growingcasts a dramatic light on the conflicting objec- economies emerging as consumption centres.tives associated with livestock production. Resource availability influences livestock pro- The need to address such tradeoffs is likely duction costs, especially land and water resourc-to become increasingly acute, and policy deci- es. Previous sections have shown that in severalsions in this area will be critical to the environ- regions of the world there is increasing competi-mental and social sustainability of the sector. tion for land and limited options for expandingAnother factor affecting the feed sector, and the feed base, while in other regions there is stillin particular the soybean market is consumer potential for expansion. In this section, we will50
    • Livestock in geographic transitionfirst review the current geographical distribu- forms of livestock production have been devel-tion of livestock and their production systems, oped to harness resources from semi-arid orin the light of the sector’s history. We will then mountainous, seasonally shifting or temporarilyexplore current spatial trends of landless and available pastures. Although many of these sys-land-based production systems. tems result from a long historical evolution, they are currently under pressure to adjust to rapidly2.4.1 Historical trends and distribution evolving socio-economic conditions. Over recentpatterns decades, large intensive livestock productionHistorically, transport and communication infra- units, in particular for pig and poultry produc-structures were more limited than today. Prod- tion have emerged in many developing regionsucts were not easily transported and technolo- in response to rapidly growing demand for live-gies were not propagated rapidly. As a result, stock products.demand and resources had to be linked locally, For clarity of analysis, it helps to classify themostly relying on locally available capital and vast variety of individual situations into a limitedtechnology mixes. Traditionally, livestock pro- number of distinct livestock production systems.duction was based on locally available feed Ideally the following criteria should be consid-resources, particularly those of limited or no ered:alternative value, such as natural pasture and • degree of integration with crops;crop residues. In a context of less developed • relation to land;communication than nowadays, cultures and • agro-ecological zone;religions were less widespread and more spe- • intensity of production;cific to limited areas. They, therefore, influenced • irrigation or rainfed; andconsumer preferences and production options in • type of product.more diversified ways. FAO (1996) has proposed a classification ofLivestock production systems eleven categories of livestock production sys-Production environments, intensities and goals tems (LPSs) based on different types of farmingvary greatly within and across countries. Animal systems, relationship to land and agro-ecologi-agriculture systems correspond to agro-ecologi- cal zone (see Figure 2.9). They identify two maincal opportunities and demand for livestock com- groups of LPSs:modities. In general, the systems are adjusted • those solely based on animal production,to the prevailing biophysical and socio-cultural where more than 90 percent of dry matter fedenvironment and, traditionally, since there were to animals comes from rangelands, pastures,no external inputs they have been, for the most annual forages and purchased feeds, and lesspart, in sustainable equilibrium with such envi- than 10 percent of the total value of produc-ronments. tion comes from non-livestock farming activi- In many of these systems, the livestock ele- ties; andment is interwoven with crop production, as in • those where cropping and livestock rearingthe rice/buffalo or cereal/cattle systems of Asia. are associated in mixed farming systems,Animal manure is often essential in maintaining where more than 10 percent of the dry mattersoil fertility, and the role of animals in nutri- fed to animals comes from crop by-productsent cycling is often an important motivation for or stubble, or more than 10 percent of thekeeping animals, particularly where this involves total value of production comes from non-a transfer of nutrients from common property livestock farming activities.resources to private land. In other cases, mobile 51
    • Livestock’s long shadow Figure 2.9 Classification of livestock production systems LIVESTOCK PRODUCTION SYSTEMS Solely Livestock Production Systems [L] Mixed Farming Systems [M] Landless LPS [LL] Grassland-based LPS [LG] Rainfed LPS [MR] Irrigated LPS [MI] Monogastric meat and Temperate zones and Temperate zones and Temperate zones and eggs [LLM] tropical highland [LGT] tropical highland [LGT] tropical highland [MIT] Humid/subhumid Ruminant meat (beef) Humid/subhumid tropics Humid/subhumid tropics tropics and subtropics [LLR] and subtropics [LGH] and subtropics [MRH] natural irr. [MIH] Arid/semi-arid tropics Arid/semi-arid tropics and Arid/semi-arid tropics and and subtropics subtropics [LGA] subtropics [MRA] natural irr. [MIA] Source: FAO (1996). Below the division between livestock-only and presence of landless or “industrial” LPSs ismixed farming, four broad groupings can be connected to both demand factors and supplydistinguished. Map 13 (Annex 1) shows the rela- determinants. They are prevalent in areas withtive predominance of these four broad groups of high population density and purchasing power,livestock production systems around the world in particular coastal areas in East Asia, Europe(Steinfeld, Wassenaar and Jutzi, 2006), while and North America, that are also connected toTables 2.9 and 2.10 show their relative prev- ocean ports for feed imports. In contrast, therealence in livestock numbers and production are areas with ample feed supply such as thedata. Two of these broad groupings are among mid-western United States and interior partsthe livestock-only systems: landless LPSs, and of Argentina and Brazil, where industrial sys-grassland-based LPSs. tems have been developed primarily using local Landless LPSs are mostly intensive systems surpluses of feed supplies. East and Southeastthat buy in their feed from other enterprises. Asia strongly dominate industrial monogastricThey are found mostly in Eastern North America, production in the developing regions. SouthernEurope, Southeast and East Asia. These are Brazil is another industrial production hotspot ofdefined as systems in which less than 10 percent global importance. Regionally important centresof the dry matter fed to animals is farm-produced, of industrial production are found, for example,and in which annual average stocking rates are in Chile, Colombia, Mexico and Venezuela, asabove ten livestock units per km2 (on average well as for chicken in the Near East, Nigeria andat the census unit level). The landless category South Africa.defined by FAO (1996) is split into landless rumi- The other three major categories are land-nant and landless monogastric systems. The based, with each category split into three52
    • Livestock in geographic transitionTable 2.9Global livestock population and production in different production systemsParameter Livestock production system Grazing Rainfed Irrigated mixed Landless/ mixed industrialPopulation (million head) Cattle and buffaloes 406.0 641.0 450.0 29.0Sheep and goats 590.0 632.0 546.0 9.0Production (million tonnes)Beef 14.6 29.3 12.9 3.9Mutton 3.8 4.0 4.0 0.1Pork 0.8 12.5 29.1 52.8Poultry meat 1.2 8.0 11.7 52.8Milk 71.5 319.2 203.7 –Eggs 0.5 5.6 17.1 35.7Note: Global averages 2001 to 2003.Source: Own calculations.depending on the agro-ecological zone: temper- systems in which more than 90 percent of theate and tropical highland; humid/subhumid trop- value of non-livestock farm production comesics and subtropics; and arid/semi-arid tropics from rainfed land use. Most mixed farming sys-and subtropics tems are rain-fed and are particularly present in Grassland-based (or grazing) systems are semi-arid and subhumid areas of the tropics andlivestock-only LPSs, often based on grazing of in temperate zones.animals on seasonal, shifting or upland pas- Irrigated mixed farming systems are foundtures, primarily found in the more marginal throughout the world, but have generally limitedareas that are unfit for cropping because of low spatial extent. Exceptions are eastern China,temperature, low rainfall or topography, and northern India and Pakistan, where mixed irri-predominant in semi-arid and arid areas. They gated systems extend over large areas. They areare defined as systems in which more than 10 defined as mixed systems in which more than 10percent of the dry matter fed to animals is farm- percent of the value of non-livestock farm pro-produced and in which annual average stocking duction comes from irrigated land use.rates are less than ten livestock units per hect- Tables 2.9 and 2.10 show the distribution ofare of agricultural land. These systems cover the production (ruminants and monogastrics) andlargest land area and are currently estimated to of animal numbers (ruminants only) over theoccupy some 26 percent of the earth’s ice-free production system groups, both globally and forland surface. This figure includes a large variety the developing regions. The 1.5 billion head ofof agro-ecological contexts with very different cattle and buffaloes, and the 1.7 billion sheeplevels of biomass productivity. and goats, are fairly evenly distributed across The other two types of land-based system the land-based systems. However, their averagepractise mixed crop and livestock farming. Mixed densities increase steeply from grazing systemssystems are prevalent in bio-climatically more to mixed irrigated systems, since the latter havefavoured ecosystems. far greater livestock-supporting capacities per Rainfed mixed farming systems are mixed unit area. 53
    • Livestock’s long shadowTable 2.10Livestock population and production in different production systems in developing countriesParameter Livestock production system Grazing Rainfed Irrigated mixed Landless/ mixed industrialPopulation (million head) Cattle and buffaloes 342.0 444.0 416.0 1.0Sheep and goat 405.0 500.0 474.0 9.0Production (million tonnes)Beef 9.8 11.5 9.4 0.2Mutton 2.3 2.7 3.4 0.1Pork 0.6 3.2 26.6 26.6Poultry meat 0.8 3.6 9.7 25.2Milk 43.8 69.2 130.8 0.0Eggs 0.4 2.4 15.6 21.6Source: Own calculations.Monogastrics shift towards landless industrial some 70 percent of mutton production and aboutsystems, ruminants remain land-based 40 percent of milk production.As yet, only a small fraction of the world’s rumi- A sharply contrasting situation is found in thenant population is found in industrial feedlots, monogastrics sector. Currently more than halfpartly owing to the fact that even in intensive of the world’s pork production originates fromproduction environments feedlots are usually industrial systems and for poultry meat thisused only in the final stage of the animal’s life share amounts to over 70 percent. About half ofcycle. The vast majority of large and small rumi- the industrial production originates from devel-nant populations are found in the developing oping countries and, though reliable populationregions. Ruminant productivity varies consider- figures are not available, variation in productivityably within each system, but overall productivity between regions is probably much lower than forin developing countries’ grazing and mixed sys- ruminants. However, huge differences in totaltems is lower than in developed countries: glob- production are found between the developingally, beef production per animal in grazing sys- regions. The majority of the world’s pork, poultrytems is 36 kg/head and year while the average and egg production from irrigated mixed sys-for developing countries is 29 kg/head and year. tems takes place in developing regions. AlthoughBy far the largest variation in intensity of produc- substantial, production in Latin America is lesstion is found within the mixed rainfed system, the than one-tenth of that in Asia, whereas produc-largest producer of ruminant products. Despite tion is almost absent in Africa and West Asia. Thethe fact that the developing regions house the developed countries and Asia together accountvast majority of animals in this category, they for over 95 percent of the world’s industrial porkaccount for less than half of the category’s production .production globally. In fact, beef productivity inthese regions averages 26 kg/head, as opposed Geographical distribution of main livestockto 46 kg/head at world level, and their milk speciesproduction is only 22 percent of the world total. The distribution of species can also be examinedAcross all four categories, developing regions by agro-ecological zone (Table 2.11). Recentaccount for half of the world’s beef production, strong industrial growth in production of mono-54
    • Livestock in geographic transitionTable 2.11Livestock population and production in different agro-ecological zonesParameter Agro-ecological zones Arid and semi-arid Humid and sub-humid Temperate and tropics and sub-tropics tropics and sub-tropics tropical highlandsPopulation (million head)Cattle and buffaloes 515 603 381Sheep and goat 810 405 552Production (million tonnes)Beef 11.7 18.1 27.1Mutton 4.5 2.3 5.1Pork 4.7 19.4 18.4Poultry meat 4.2 8.1 8.6Milk 177.2 73.6 343.5Eggs 4.65 10.2 8.3Note: Global averages 2001 to 2003.Source: Own calculations.gastrics in the tropics and subtropics has led to counts 6.9 birds per hectare of agriculture land.production levels that are similar to that of tem- When related to human population, the highestperate regions. The situation is very different for poultry/person ratios are found in North Americaruminant production, partly because of its land- (6.7 birds per person), followed by Latin Americabased nature; production and productivity are at only 4.5 birds per person. This is consistentmuch higher in the cooler climates. Small rumi- with high poultry exports from these two regionsnant production in the (semi)arid (sub)tropics (see Table 14, Annex 2).is a notable exception, explained by the large Historically, the distribution of pig populationspopulation and the relatively high productivity, was closely related to that of humans. The highthe latter being the result of the species’ fitness concentration of the pig industry in specializedunder harsh and marginal conditions. The rela- regions has lead to strong subnational concen-tively low productivity for milk in the more humid trations (see Map 17, Annex 1). The tendencytropics relates to the strong dominance of mixed for pigs to be more concentrated than poultrysystems in these regions, where use of animals in areas with high animal densities is also illus-for draught power and other uses such as trans- trated in Figure 2.10. This trend may result fromport is still substantial. the high environmental impact of pig production. Of all livestock species, poultry has the closest The other striking feature of pig distribution isdistribution pattern to human populations (see their relative absence from three regions (WestMap 16, Annex 1). This may seem surprising, Asia and North Africa, sub-Saharan Africa andas poultry is predominantly raised in intensive South Asia) for cultural reasons – see Table 7,systems, but the reason is that intensive sys- Annex 2. On the other hand, the highest pig den-tems are widely spread. On a global average, sities in relation to agricultural land and humanthree birds are found per hectare of agriculture population are recorded in Europe and Southeastland, with the highest concentrations found in Asia.Western Europe (7.5 birds/ha), East and South- Major cattle densities are found in India (witheast Asia (4.4) and North America (4.3). China an average of more than one head of cattle per 55
    • Livestock’s long shadow Figure 2.10 Comparative distribution of pig Map 20 (Annex 1) shows global geographi- and poultry cal trends of aggregated livestock distribution, 35 expressed in terms of livestock units. We observe six major areas of livestock concentration: Cen- 30 tral and Eastern United States, Central America, Livestock units per km 2 25 South Brazil and North Argentina, Western and 20 Central Europe, India and China. Four areas have 15 densely concentrated areas of a lesser extent: 10 Eastern Africa, South Africa, Australia and New 5 Zealand. 0 5 10 25 50 75 90 95 First Median Third Recent distribution trends quantile quantile Monogastrics expand faster than ruminants Grid cells (Percentage) The comparisons between two quantifications of Poutry Pig the world livestock productions systems study Source: Calculation based on Maps 16 and 17 (Annex 1). by FAO, (1996) (averages for 1991–93 and for 2001–03) show that significant changes in resource endowments have brought about changes in the nature and extent of produc-hectare of agriculture land), northeastern China tion systems. Cattle stocks are slightly up on(mostly dairy), Northern Europe, Southern Brazil the world level (5 percent), with a considerableand the East African Highlands (see Map 18, increase in stock numbers for sub-SaharanAnnex 1 and Table 8, Annex 2). Smaller con- Africa, Asia and Latin America. A strong drop incentrations are also found in the United States, animal numbers (almost 50 percent) occurred inCentral America and Southern China. Although the Eastern European and CIS countries follow-large concentrations are not recorded in Ocea- ing geopolitical changes and the collapse of thenia, the region has more cattle than inhabitants, Soviet Union.especially in Australia where the cattle popula- World output rose by about 10 percent intion is about 50 percent greater than the human the period of observation, with very strong dif-population. Average stock per agricultural land ferences at regional level. Cattle meat outputhere is, however, among the lowest, in line with almost doubled in Asia. In sub-Saharan Africathe extensive nature of cattle production. it increased by 30 percent, in Latin America by Small ruminants are uncommon in the Ameri- 40 percent, and in West Asia and North Africacas, except for Uruguay and, to a lesser extent, by about 20 percent, albeit from a lower abso-Mexico and Northern Brazil (see Map 19, Annex lute level. The strongest cattle output increases1 and Table 9, Annex 2). In contrast, high densi- occurred in mixed systems in the humid zones.ties are found in South Asia and Western Europe At lower overall production levels (see Table 2.9(1.3 and 0.8 head per hectare of agricultural land and 2.10) total meat production from small rumi-respectively), and there are local concentrations nants increased by about 10 percent, althoughin Australia, China, Northern Africa and African the overall stock numbers for small ruminantsdry lands. As in the case of cattle, sub-Saharan remained fairly constant for the two referenceAfrica shows higher animal to human population periods. There were inter-regional shifts in dis-ratios than the world average, which is explained tribution. Stock numbers increased considerablyby the heavy reliance on ruminants and the low in sub-Saharan Africa and Asia, and stronglyproductivity of animals. declined in Latin America, the OECD, and in56
    • Livestock in geographic transitionparticular in Eastern Europe and the CIS. The Figure 2.11 Changes in geographical increases occurred mainly in mixed humid sys- concentration of hens in Brazil from 1992 to 2001tems. The changes in monogastric animal pro-duction are more striking. Total pig meat output 100(the highest meat output per species in 2002) 90rose by 30 percent at world level, an increase 80accounted for almost entirely by Asia. Most Hens (%, cumulative) 70regions showed increases in pig meat produc- 60tion, although for Eastern Europe and the CISthere was a drop of about 30 percent. Industrial 50pig meat production grew at about 3 percent 40per year. Strong increases also occurred in the 30humid and temperate mixed irrigated systems. 20 The total production of poultry meat grew by 0 5 10 15 20 25 30 Area (%, cumulative)about 75 percent, the strongest expansion of all 1992 1998 2001livestock products. Regional differences werepronounced, with an extremely strong expansion Source: Own calculations.in Asia (about 150 percent increase, with a yearlygrowth rate of over 9 percent). The growth rateswere generally positive, between 2 and 10 per- Figure 2.12 Changes in geographical cent across regions, most of this resulting from concentration of pigs in Brazil from 1992 to 2001expansion of industrial systems. Global produc-tion of table eggs grew by about 40 percent. Asia 100more than doubled its egg production in the 90period, to reach a share of about 50 percent of 80 Pig stocks (%, cumulative) 70world production. The landless livestock produc- 60tion system grew by about 4 percent per year. 50 402.4.2 Geographical concentration 30The industrialization of livestock production 20occurs where economic growth is taking place 10(see Chapter 1). Thus, new farming systems are 0dominant in industrialized countries and coun- 0 5 10 15 20 25 30 Area (%, cumulative)tries with rapid economic growth. A characteristic 1992 1998 2001of such production systems is the segmentationof production stages (feed production, animal Source: Own calculations.raising, slaughtering and processing) and thelocation of each segment where operating costsare minimized. In this process, animal farms tendto concentrate geographically into clusters. graphical concentration for hens than for pigs, The trend of landless production systems and an increasing concentration for both spe-towards clustering is ongoing in developed as cies over the 1992 to 2001 period (see Figureswell as developing economies. The analysis of 2.11 and 2.12). In 1992, 5 percent of the totalthe pig and poultry populations at municipal country’s area hosted 78 percent of the henlevel in Brazil shows a more accentuated geo- population, rising to 85 percent of the population 57
    • Livestock’s long shadow Figure 2.13 Changes in geographical in 2001. The corresponding figures for pigs over concentration of pigs in France the same period are 45 percent and 56 percent from 1989 to 2001 respectively. A similar analysis conducted for 90 France and Thailand (see Figures 2.13 and 2.14) 80 showed concurring results. Pigs (%, cumulative) 70 Landless production systems 60 A two-step move: rural to urban, urban to sources of feed 50 As developing countries industrialize, livestock 40 production generally relocates in two stages (Gerber and Steinfeld, 2006). As soon as urban- 30 ization and economic growth translate rising 0 5 10 15 20 25 30 Area (%, cumulative) population into “bulk” demand for animal food 1989 1992 2001 products, large-scale operators emerge. At the Source: Own calculations. initial stage, these are located close to towns and cities. This occurs because livestock products Map 2.1 Location of industrial pig sector in southern Viet Nam (Dong Nai, Binh Duong, Ho Chi Minh city and Long An province) Pig farm Feed mill Slaughterhouse Urban area (standing pig population) (tonnes per year) (head per day) 1 000 10 000 10 10 000 50 000 100 Road 100 000 100 000 1 000 0 15 30 60 Kilometres Source: Tran Thi Dan et al., (2003).58
    • Livestock in geographic transitionare among the most perishable products, and Figure 2.14 Changes in the peri-urban their conservation/transport without chilling and concentration of poultry from 1992 to 2000 in Thailandprocessing poses serious problems. Therefore,as long as transport infrastructures remain 1 800 Chicken density within concentric ring 1 600inadequate, livestock-derived foods have to be 1 400produced in the vicinity of demand. Map 2.1 illus- 1 200trates how the intensive pig sector has located 1 000at the periphery of Ho Chi Minh City in Viet Nam. 800Most feed mills, pig farms and slaughterhouses 600are found within 40 km of the city centre. 400 200 In a second phase, transport infrastructure 0and technology develop sufficiently to make it 50 100 150 200 250 300 350 400 450 500technically and financially possible to keep live- Distance to Bangkok 1992 2000stock further away from demand centres. Live-stock production then shifts away from urban Source: Own calculations.areas, driven by a series of factors such aslower land and labour prices, access to feed,lower environmental standards, tax incentives of these clusters was affected by the increasingand fewer disease problems. Following a simi- use of imported feed. Those with good connec-lar trend, the poultry density in areas less than tion to ports strengthened (e.g. Brittany, western100 km from Bangkok decreased between 1992 Denmark, Flanders) and new production areasand 2000, with the largest decrease (40 percent) appeared in the vicinity of major ports (Lowerin the areas close to the city (less than 50 km). Saxony, Netherlands, Catalonia). Finally, a morePoultry density increased in all areas further recent type of feed-related production cluster isthan 100 km away (see Figure 2.14). In this par- observed close to newly created feed process-ticular case, the geographical shift was further ing plants establishing comprehensive animalaccelerated by tax incentives. production chains. Concentration close to feed When pushed out of peri-urban areas, land- processing plants is observed in Brazil by analy-less production systems tend to move closer to sis of pig numbers and feedcrop production atfeed resources so as to minimize transport costs Municipio level in Brazil. From 1992 to 2001, parton the input side, since the feed used per head of the pig population moved away from tradi-is bulkier than the livestock produced. The shift tional feed production areas and concentratedoccurs either towards feed production areas (e.g. around major feed mills in Mato Grosso.the United States corn belt, Mato Grosso in Bra- Disease control strategies may, however,zil, Mexican El Bajio), or towards feed importing scatter production clusters. To limit the spreadand processing areas (e.g. Chachoengsao Prov- of diseases, large farms tend to scatter awayince of Thailand, Jeddah in Saudi Arabia). from other large farms and small-scale units. A In OECD countries, where industrialization of distance of a few kilometres is sufficient to pre-the livestock sector began from 1950 on, clus- vent disease propagation. It is therefore probableters formed in rural areas with surplus cereal that this trend will prevent the concentration ofsupply. Here, livestock were initially produced as small- and large-scale farms, especially in peri-a means of diversification and value addition. In urban settings, but will most probably not alterEurope, pig and poultry production clusters of the trend towards specialized areas, equippedthis type include Brittany, the Po valley in Italy, with feed mills, slaughterhouses and animalWestern Denmark and Flanders. The geography health services. 59
    • Livestock’s long shadowLand-based systems: towards intensified systemsFodder is bulky and its transportation expensive.Livestock raised in land-based systems are,therefore, bound to feed resource productionareas. Previous sections have, however, shownthat pasture expansion is likely to be limited, © USDA/Joseph Valbuenablocked on one side by lack of suitable land andon the other by competition from land uses withlower opportunity costs (e.g. agriculture, for-estry, conservation). As a result, pushed by an increasing demandfor beef and milk, part of the production shifts Transporting chickens to poultry plantfrom land based towards intensified systems, near Magee – United Statessuch as feedlots and dairy plants (see Chapter1), following the same geographical trend asintensive monogastric production. America. For comparison, world production as a Land-based systems also tend to expand into whole increased by 124 percent for the two prod-the remaining areas with good potential for pas- ucts over the same period (FAO, 2006b).ture or where there are no strong land use com- These overall trends are confirmed by localpetitors. These are predominantly found in Ocea- analysis. Cattle numbers per Municipio in Brazilnia and South America. Over 1983 to 2003, beef in land-based livestock systems show a moreand milk production grew by 136 percent and even geographical spread of cattle (see Figure196 percent respectively in Oceania, and by 163 2.15) than was observed for stock in landless,percent and 184 percent respectively in South intensive systems. The expansion of pasture into the Amazon is further described in land degra- dation hotspots (Section 2.5 below). Figure 2.15 Changes in geographical concentration of cattle in Brazil 2.4.3 Increasing reliance on transport from 1992 to 2001 Trade and transport improvements increase 100 transport of livestock products 90 The transport of livestock sector commodities 80 has become increasingly economically afford- Cattle (%, cumulative) 70 able and technically possible. Technical changes 60 in transport, such as the development of infra- 50 structure, large-scale shipments of primary crop 40 production or consolidation of long-distance cold 30 chains, have played a determinant role in shap- 20 ing change in the livestock sector. 10 Developments in transport have made it pos- 0 sible to bridge the geographical gap between 0 5 10 15 20 25 30 Area (%, cumulative) urban demand for animal products and the land 1992 1998 2001 resources for their production. Increased trade and transport of animal products and feedstuff Source: Own calculations (2005). are also fundamental factors in the industrializa- tion of the livestock sector. Because they operate60
    • Livestock in geographic transitionon a large scale, with considerable volumes of meat, and milk produced worldwide were traded,inputs and outputs, landless industrial systems and 8.2 percent of pig meat. All of these sharesintrinsically rely on transport for supply of inputs were significantly up on the 1981–83 average.(especially feed) and delivery of outputs. Fur- Among feeds, trade in soymeal represented athermore, the low private costs of transport higher share of production (24–25 percent) over(which rarely factor in social and environmental the same periods, though showing little increasecosts) have strongly influenced the location eco- (see Table 2.12). For feedgrains the traded sharenomics of the various segments of the livestock of total production has also remained fairly con-commodity chain, from feed production and feed stant. Trade increases were fostered by a num-mill, to animal production, slaughtering and pro- ber of policy measures and agreements aimedcessing. Since the transport cost of connecting at easing international trade, including regionaleach segment is limited, other production costs trade agreements, harmonization of standardsplay a greater role in determining location. Such and the inclusion of agriculture in the Worldparameters include cost of land, labour, ser- Trade Organization (WTO) mandate.vices, health control, tax regimes and strictnessof environmental policy. Although to a lesser Feed trade: Americas dominate exports, China andextent than landless industrial systems, land- EU dominate importsbased production systems increasingly rely on As livestock production grows and intensifies, ittransport, as they shift closer to available land depends less on locally available feed resourcesresources and further away from consumption and more on feed concentrates that are tradedcentres. domestically and internationally. Map 21 and 22 Worldwide, most livestock are produced for (Annex 1) display estimated spatial trends in feednational consumption. However, animal prod- surplus/deficit for pig and poultry, providing evi-ucts are increasingly traded, and a larger share dence of the sector’s high reliance on trade. Feedof the global production enters trade nowadays trade and the related transfers of virtual water,than in the 1980s. The trend was particularly nutrients and energy is a determinant factor ofdynamic for poultry meat, where the interna- the sector’s environmental impacts. Statisticstionally traded share rose from 6.5 percent in on feedgrains are generally not separate from1981–83 to 13.1 percent in 2001–03. In 2001–03, overall grain trade flows. However, major trendsmore than 12 percent of bovine meat, poultry can be inferred from regional level trade flows, as shown in Table 10 of Annex 2 for maize. North and South America are the two regions withTable 2.12 significant interregional exports. The maize thatTrade as a share of total production for selected they export to Africa is predominantly used forproducts food, while a large share of exports to Asia, EUProduct 1981–1983 2001–2003 and America supplies feed demand (Ke, 2004). average average Asian maize demand, driven by the feed sector, (........................ % ........................) is predominantly supplied by North America,Bovine meat 9.4 13.0 although imports from South America increasedPig meat 5.2 8.2 dramatically over the period. North AmericaPoultry meat 6.5 13.1 also exported large volumes of maize to SouthMilk equivalent 8.9 12.3 and Central America (2.8 and 9.2 million tonnesSoymeals1 24.3 25.4 respectively (2001 to 2003 average). Both flows1 Soymeal trade over soybean production. have increased strongly over the past 15 years.Source: FAO (2006b). On the other hand South America dominates 61
    • Livestock’s long shadowthe EU market. Contrasted country profiles and al trade, with the EU as first client and Asia asstrategies explain these trends. Exports from second (18.9 and 6.3 million tonnes respectivelyNorth and South America are driven by coun- in 2002). The United States has a lesser role intries (e.g. Argentina, Canada, United States) with soymeal interregional trade. In recent years, aample land resources and strong grain export number of importing countries, especially in thepolicies. On the other hand, China, which is a EU have shifted from the importation of soymealmajor driver of Asian imports, compensates for to purchases of beans, which reflects efforts toits land shortage with imports. promote processing at the local level. As a result, The comparison of grain resources and grain about six million tonnes of soymeal produced inrequirements at the local level allow estimating the EU enter trade, mostly intraregional, but alsodomestic trade (see Map 21, Annex 1), although towards Eastern Europe. There is also interna-imports from international markets would most tional trade in other fodder products, such asprobably supply part of the demand in deficit processed alfalfa and compressed hay bales.areas. Exporting countries are predominantly Canada About one-third of global soybean, soy oil and and the United States. Japan is by far the largestsoymeal production is traded (29.3, 34.4 and 37.4 importer, followed by the Republic of Korea, andpercent respectively). This proportion is signifi- Taiwan Province of China.cantly above that recorded for other agriculturalcommodities. Soymeal and soybeans account for Animal and derived products trade increases35 and 50 percent of the total value of soy-based globallytrade, respectively (FAO, 2004a). The widespread Live animals and animal-derived products areconsumption of soybeans is supplied by a few traded in smaller volumes than feed, becausemajor exporting countries to a large number of smaller demand volumes and greater privateof importing countries (see Table 11 and Table costs of transport per unit. Nevertheless, the12, Annex 2 and Map 22, Annex 1). The United growth of trade in animal products is outpacingStates is the largest soybean exporter (29 million the growth of feed trade and of animal produc-tonnes), followed by Brazil (17 million tonnes). tion. This rapid growth is facilitated by weakeningAmong the top seven producers, China is the tariff barriers within the context of GATT, and byonly one with decreasing exports over the period the preparation of codes and standards to regu-(see Table 11, Annex 2). Indeed, over the past 10 late global trade. In parallel, the trend towardsto 20 years China has gone from being a soybean increased demand for processed products byexporter to being the world’s largest importer of households and catering further expanded thewhole soybeans and a large importer of soymeal transport of animal products.– with one-third of its soymeal consumption sup- Trade in poultry meat has overtaken trade inplied by imports. beef over the past 15 years, with volume soaring Countries import soybeans either raw, or pro- from about 2 million tonnes in 1987 to 9 millioncessed into soy oil and/or soymeal, depending tonnes in 2002, compared to beef’s rise fromon domestic demand, which is also determined 4.8 to 7.5 million tonnes over the same period.by the structure of the local processing industry. Except for Eastern Europe, all analysed regionsThe United States exports about 35 percent of became increasingly involved in trade (see Tableits raw soybeans, before processing. In contrast, 14, Annex 2). North America supplies about halfArgentina and Brazil add value to most of their of the interregional market (2.8 million tonnescrop, process about 80 to 85 percent of their per year on average, between 2001 and 2003),soybeans before export (Schnittker, 1997). For followed by South America (1.7 million tonnes)soymeal, South America dominates interregion- and the EU (900 000 tonnes). Brazil is the top62
    • Livestock in geographic transitionexporting country. With relatively low feedgrain recent years (686 thousand tonnes per year onand labour costs and increasingly larger econ- average, between 2001 and 2003, a 173 percentomies of scale, Brazil’s production costs for increase in 15 years). South American exportswhole eviscerated chicken are estimated to be go mainly to the EU (390 thousand tonnes perthe lowest of any major supplier (USDA‑FAS, year on average, between 2001 and 2003) and2004). On the importer side, the picture is more Asia (270 thousand tonnes), both volumes havingdiversified than for beef, with several regions roughly doubled over the past 15 years. The EUplaying important roles. Asia ranks number one, and North America also make large contribu-followed by the Baltic states and CIS, the EU, tions to global bovine meat supply, based onsub-Saharan Africa and Central America. Impor- more intensive production systems, especiallytant and rapidly increasing regional level trade in the United States. Most of the EU’s trade isis taking place in Asia and the EU, both regions within the EU region, although the EU alsoyielding local competitive advantages. supplied the Baltic states and CIS countries in To assess transport of meat further, we cal- 2002. North America predominantly suppliesculated balances between primary production Asia, which is by far the biggest beef importerand demand for animal products at the local of all ten analysed regions, importing aboutlevel. The results for poultry meat are shown on 1.8 million tonnes of beef per year on average,Map 23 (Annex 1). Production is similar to con- between 2001 and 2003 (see Table 13, Annex 2).sumption on a majority of grid cells. A balanced Asian imports, driven by China, are also the mostsituation (set as +/- 100 kg of meat per km2) is dynamic, with a 114 percent increase over thegenerally found in land-based systems (compare 1987 to 2002 period. Asia responds to its soaringwith Map 13, Annex 1). Areas of highly positive demand through interregional trade, but also bybalances (surplus) are associated with landless drawing upon a booming intraregional beef meatindustrial systems (Map 14, Annex 1), whereas market. Interregional trade is also building up innegative balances (deficit) usually coincide with Sub-Saharan Africa. Finally, Table 13 (Annex 2)high population densities and urban areas. The illustrates the collapse of Eastern Europe overpoultry exporting position of North and South the period, with imports from North America,America shows up here as a dominance of sub-Saharan Africa and the Baltic States andred (surplus) pixels in these two regions. The CIS that are close to zero. The estimated beefsame analysis conducted for pig meat (Map 24, balances (Map 25, Annex 1) display the need forAnnex 1) shows a similar coincidence of posi- both domestic trade and international trade.tive balances with industrial production areas.However, poultry and pig meat differ in the 2.5 Hotspots of land degradationgeographical spread of areas with negative and As a major land user, the livestock sector has apositive balances. Production areas are gener- substantial influence on land degradation mech-ally more scattered among consumption areas anisms in a context of increasing pressure onfor poultry than for pigs. The three maps also land (see Box 2.3). With regard to land-basedshow important domestic trade. systems, two areas pose the most serious prob- Beef is predominantly exported from Oceania lems. There is the ongoing process of degrada-and South America, taking advantage of their tion of pastures, particularly in the arid andland-based cattle production systems (Table 13, semi-arid environments of Africa and Asia, butAnnex 2). North America is the main market for also in subhumid zones of Latin America. ThereOceania (903 thousand tonnes per year on aver- is also the issue of pasture expansion, and theage, between 2001 and 2003), but Asian imports conversion of forest land into pastures, particu-from Oceania have dramatically increased in larly in Latin America. 63
    • Livestock’s long shadow Landless industrial systems are disconnected 2.5.1 Pastures and feedcrops still from the supporting land base. The separation of expanding into natural ecosystems production from resources often creates pollu- Crop and pasture expansion into natural eco- tion and soil degradation problems, both at feed systems has contributed to livestock production production and animal operation levels. In paral- growth, and will probably do so in the future under lel, feedcrop expansion into natural ecosystems the “business as usual” scenario. Whatever the creates land degradation. purpose, the destruction of natural habitats to In the following sections, we will review four establish agricultural land use means direct and major mechanisms of land degradation related significant biodiversity losses. The Millennium to the livestock sector: Ecosystem Assessment (MEA) lists land-use • expansion into natural ecosystems; change as the leading cause of biodiversity loss • rangeland degradation; (MEA, 2005a). The destruction of vegetative cover • contamination in peri-urban environments; also leads to carbon release, fuelling climate • pollution, soil degradation and productivity change. In addition, deforestation affects water losses in feedcrop production areas. cycles, reducing infiltration and storage and increasing runoff by the removal of canopies and We will assess the geographical extent of these leaf litter, and through the reduced infiltration problems, as well as their underlying biophysical capacity of the soil as a result of reduced humus process. Impacts on the global environment will content (Ward and Robinson, 2000). simply be listed here. Implications on climate In OECD countries, the decision to plant soy- change, water depletion and biodiversity erosion beans or grain does not usually mean clearing will be further developed in later chapters. natural habitat. Producers merely make a choice© Greenpeace/Alberto César Illegal deforestation for soybean production in Novo Progresso, State of Pará – Brazil 2004 64
    • Livestock in geographic transition Box 2.3 Ecological footprint To measure humanity’s pressure on land and that humanity’s ecological footprint is currently 20 increasing competition for scarce resource, the percent larger than the entire planet can sustain. In Global Footprint Network defined an indicator other words, it would take one year and two months called the ecological footprint. The ecological foot- for the earth to regenerate the resources used by print measures how much land and water area humanity in a single year. a particular human population requires to pro- Livestock-related activities contribute signifi- duce the resources it consumes and to absorb its cantly to the ecological footprint, directly through wastes, taking into account prevailing technology land use for pasture and cropping, and also indi- (Global Footprint Network). This indicator allows rectly through the area needed to absorb CO2 emis- us to compare the use of resources with their avail- sions (from fossil fuel use in livestock production) ability. The Global Footprint Network estimates and ocean fisheries (related to fishmeal production that global demand for land overtook global sup- for feed). ply by the end of the 1980s. It is further estimated Figure 2.16 Ecological footprint per person, by component 2.50 2.00 Global hectares/person 1.50 1.00 0.50 0.00 1961 1966 1971 1976 1981 1986 1991 1996 2001 Crops Forests CO2 absorption Built-up land Pasture Fuelwood Nuclear area Fisheries Source: Global Footprint network (available at http://www.footprintnetwork.org). 65
    • Livestock’s long shadowbetween a number of crops, within an agricul- in areas currently under humid and subhumidtural area that remains roughly stable. In many forest. There is little evidence of the livestocktropical countries, however, the cultivation of sector being a major factor in deforestation incrops is often driving the process of converting tropical Africa. Timber harvesting and fire seemextended areas of natural habitat to agriculture. to be the two main processes leading to defor-This is the case in much of tropical Latin Ameri- estation. Cases of farming replacing forest areca, sub-Saharan Africa and Southeast Asia. Soy- predominantly due to small-scale cropping, or tobeans in particular are a driving force. Between using secondary forest and scrub land for wood1994 and 2004, land area devoted to growing soy- harvesting.beans in Latin America more than doubled to 39million ha, making it the largest area for a single Main global environment concerns associatedcrop, far above maize, which ranks second at with feedcrop and pasture expansion into natu-28 million hectares (FAO, 2006b). In 1996, there ral ecosystems include climate change, throughwere only 1 800 hectares of soybeans in Rondô- biomass oxidation and carbon release into thenia in the western Amazon, but the area planted atmosphere; water resources depletion throughincreased to 14 000 hectares in 1999. In the east- disruption of water cycles and; biodiversity ero-ern Amazon in the state of Maranhão the area sion through habitat destruction. These issuesplanted with soybeans increased from 89 100 to will be reviewed in Chapter 3, 4 and 5, respec-140 000 hectares between 1996 and 1999 (Fearn- tively.side, 2001). The demand for feed, combined withother factors, has triggered increased produc- 2.5.2 Rangeland degradation: tion and exports of feed from countries like Bra- desertification and vegetation changeszil where land is relatively abundant. Pasture degradation related to overgrazing by The land area used for extensive grazing in the livestock is a frequent and well studied issue.neotropics has increased continuously over the Pasture degradation can potentially take placepast decades and most of this has been at the under all climates and farming systems, andexpense of forests. Ranching-induced defores- is generally related to a mismatch betweentation is one of the main causes of loss of unique livestock density and the capacity of the pastureplant and animal species in the tropical rainfor- to be grazed and trampled. Mismanagement isests of Central America and South America as common. Ideally the land/livestock ratio shouldwell as of carbon release into the atmosphere. be continuously adjusted to the conditions ofLivestock production is projected to be the the pasture, especially in dry climates wheremain land use replacing forest in the neotropics biomass production is erratic, yet such adjust-after clearing. Indeed, Wassenaar and col- ment is rarely practiced. This is particularly theleagues (Wassenaar et al., 2006) estimate that case in the arid and semi-arid communal graz-the expansion of pasture into forest is greater ing areas of the Sahel and Central Asia. In thesethan that of cropland. For South America, Map areas, increasing population and encroachment33B (Annex 1) indicates deforestation hotspots of arable farming on grazing lands, have severelyand areas with a more diffuse deforestation restricted the mobility and flexibility of the herds,pattern. The full ecological and environmental which enabled this adjustment. Pasture degrada-consequences of such deforestation processes tion results in a series of environment problems,are not yet fully understood and deserve greater including soil erosion, degradation of vegetation,attention from the scientific community. This is a carbon release from organic matter decomposi-particularly acute issue, since the major poten- tion, loss of biodiversity owing to habitat changestial for pasture expansion exists predominantly and impaired water cycles.66
    • Livestock in geographic transition Concentrated “hoof action” by livestock soil conditions (e.g. organic matter, nutrients,– in areas such as stream banks, trails, water- soil moisture).ing points, salting and feeding sites – causes Woody encroachment has been well docu-compaction of wet soils (whether vegetated or mented in semi-arid, subtropical rangelands ofexposed) and mechanically disrupts dry and the world. There are hotspots in North and Southexposed soils. The effects of trampling depend America, Africa, Australia and elsewhere, whereon soil texture – soils with greater fractions of silt woody vegetation cover has increased signifi-and clay are more easily compacted than sandy cantly during the past few decades. Among thesoils. Compacted and/or impermeable soils can causes are overgrazing of herbaceous species,have decreased infiltration rates, and therefore suppression of fires, atmospheric CO2 enrich-increased volume and velocity of runoff. Soils ment and nitrogen deposition (Asner et al., 2004;loosened by livestock during the dry season are van Auken, 2000; Archer, Schimel and Holland,a source of sediments at the beginning of the 1995).new rainy season. In riparian areas the desta- The extent of grassland degradation in aridbilization of streambanks by livestock activities and semi-arid climates is a serious source ofcontributes locally to a high discharge of eroded concern and debate, as its quantification is com-material. Furthermore, livestock can overgraze plex. There is a lack of reliable and easily mea-vegetation, disrupting its role of trapping and surable land quality indicators, ecosystems alsostabilizing soil, and aggravating erosion and pol- fluctuate, and the annual vegetation of these aridlution. Ruminant species have distinct grazing areas has shown to be highly resilient. For exam-habits and thus different aptitude to cause over- ple, after a decade of desertification in the Sahel,grazing. For instance, goats being able to graze there is now evidence of increasing seasonalresidual biomass and ligneous species have also greenness over large areas for the period 1982the greatest capacity to sap grasslands’ resil- to 2003. While rainfall emerges as the dominantience. (Mwendera and Mohamed Saleem, 1997; causative factor for the increase in vegetationSundquist, 2003; Redmon, 1999; Engels, 2001; greenness, there is evidence of another caus-Folliott, 2001; Bellows, 2001; Mosley et al., 1997; ative factor, hypothetically a human-inducedClark Conservation District, 2004). change superimposed on the climate trend. The Asner et al. (2004) suggest three types of notion of human induced irreversible degrada-ecosystem degradation syndromes related to tion of the Sahelian rangelands is thus chal-grazing: lenged (Herrmann, Anyamba and Tucker, 2005).• desertification (in arid climates); On the other hand, desert is rapidly gaining on• increased woody plant cover in semi-arid, pasture in northwestern China (Yang et al., 2005). subtropical rangelands; and Diverse estimates exist for the extent of deserti-• deforestation (in humid climates). fication. According to the Global Assessment of Human and Induced Soil Degradation methodol- The role of livestock in the deforestation pro- ogy, the land area affected by desertification iscess has been reviewed in Section 2.1 above. 1.1 billion ha, which is similar to UNEP estimatesAsner and colleagues describe three major ele- (UNEP, 1997). According to UNEP (1991), whenments of desertification: increased bare soil rangelands with degraded vegetation are addedsurface area; decreased cover of herbaceous (2.6 billion ha), the share of dry lands that arespecies; and increased cover of woody shrubs degraded is 69.5 percent. According to Oldemanand shrub clusters. and Van Lynden (1998), the degraded areas for The overarching pattern is one of increased light, moderate and severe degradation are 4.9,spatial heterogeneity of vegetation cover and of 5.0 and 1.4 billion hectares, respectively. How- 67
    • Livestock’s long shadow© FAO/6077/H. Null Soil erosion in the Solo River basin – Indonesia 1971 ever, these studies do not take into account of acute locally. For example Jansen et al. (1997) vegetation degradation. Map 27 (Annex 1) shows estimated that over 70 percent of the pastures the location of grasslands established on weak in the Northern Atlantic zone of Costa Rica are soils in harsh climates, which face significant in an advanced stage of degradation, with over- risks of degradation if ill-managed. grazing and lack of sufficient N input identified In addition, there is the risk of pasture deg- as principal causes. radation in humid to temperate climates. When stocking rates are too high, the removal of Main global environment concerns associ- nutrients (especially nitrogen and phosphorus) ated with rangeland degradation include cli- via livestock products and via soil degradation mate change, through soil organic matter oxida- processes may be higher than the inputs, and tion and carbon release into the atmosphere; soils are “mined”. In the long run, this results water resources depletion through reduction in pasture degradation, evidenced by productiv- of groundwater replenishment and biodiver- ity decline (Bouman, Plant and Nieuwenhuyse, sity erosion, through habitat destruction. These 1999). With decreasing soil fertility, weeds and issues will be further assessed in Chapter 3, 4 undesired grass species compete more strongly and 5, respectively. for light and nutrients. More herbicides and manual labour are needed to control them, 2.5.3 Contamination in peri-urban which has a negative impact on biodiversity and environments on farmers’ income (Myers and Robbins, 1991). The ongoing geographical concentration of live- Pasture degradation is a widespread issue: half stock production systems was described previ- of the 9 million hectares of pasture in Central ously, first in peri-urban settings, then close America is estimated to be degraded (Szott et to feed production and processing. In parallel, al., 2000). Pasture degradation can be even more animal-derived food processing also locates in 68
    • Livestock in geographic transitionperi-urban areas, where the costs of transport, can threaten soil fertility owing to unbalancedwater, energy and services are minimized. The or even noxious nutrient concentrations.geographical concentration of livestock, in areas • Natural areas such as wetlands and man-with little or no agricultural land, leads to high grove swamps are directly impacted by waterimpacts on the environment (water, soil, air pollution often leading to biodiversity losses.and biodiversity), mainly related to manure andwaste water mismanagement. Nutrient over- Results from LEAD studies show that in mostloads can result from several forms of misman- Asian contexts, the recycling of animal manureagement, including overfertilization of crops, on crops or in fish ponds (including sanitationoverfeeding of fish ponds and improper waste costs) is a less expensive option than manuredisposal of agricultural (e.g. livestock) or agro- treatment as nutrients are removed using bio-industrial wastes. Nutrient overloads coming chemical processes (Livestock waste manage-from crop–livestock systems mainly occur when ment in East Asia project – LWMEA) (see Box 2.4).the nutrients present in manure are not properly When production or processing units are locatedremoved or recycled. The major effects of animal in peri-urban settings, far from crops and fish-waste mismanagement on the environment have ponds (see Figure 2.17), high transport costsbeen summarized by Menzi (2001) as follows: make recycling practices financially unprofitable.• Eutrophication of surface water (deterio- Production units also often face high land prices rating water quality, algae growth, dam- and therefore tend to avoid building adequately age to fish, etc.) owing to input of organic sized treatment facilities. The result is often a substances and nutrients when excreta or direct discharge of animal manure into urban wastewater from livestock production get waterways, with dramatic consequences on their into streams through discharge, runoff or nutrient, drug and hormone residues and organ- overflow of lagoons. Surface water pollution ic matter load. Manure products with high value threatens aquatic ecosystems and the quality (e.g. chicken litter, cattle dung) are, however, of drinking-water taken from streams. Nitro- often marketed out of the peri-urban area. gen and phosphorus are both nutrients often There are also a number of animal diseases associated with accelerated eutrophication that are associated with increasing intensity of of surface water (Correll, 1999; Zhang et al., production and concentration of animals in a 2003). However, phosphorus is often the lim- limited space. Many of these zoonotic diseases iting factor to the development of blue-green pose a threat to human health. Industrial and algae, which are able to utilize atmospheric intensive forms of animal production may be a N2. Therefore, phosphorus management is often identified as a key strategy to limit sur- face water eutrophication from agricultural sources (Mainstone and Parr, 2002; Daniel et al., 1994).• Leaching of nitrate and possible transfer of pathogens to groundwater from manure- storage facilities or from fields on which high doses of manure have been applied. Nitrate © FAO leaching and pathogen transfer are particular threats for drinking water quality.• Excess accumulation of nutrients in the soil Farms in Prune – India, situated in proximity to when high doses of manure are applied. This apartment buildings 69
    • Livestock’s long shadow Figure 2.17 Spatial distribution of humans, livestock and feed crops around Bangkok, 2001 140 40 120 Mean normalized crop production 30 100 Human or animal density 80 20 60 40 10 20 0 0 50 100 150 200 250 300 350 400 450 500 Distance to Bangkok (km) Pigs (head/km ) 2 Maize (tonnes/km2) Soybean (10 tonnes/km2) Human population (persons/km2/10) Chicken (head/km2/10) Cassava (tonnes/km2/2) Source: Own calculations.breeding ground for emerging diseases (Nipah will be further assessed in Chapter 3, 4 and 5,virus, BSE), with public health consequences. respectively.Intra- and interspecies contamination risks areespecially high in the peri-urban environment 2.5.4 Intensive feedcrop agriculturewhere high densities of humans and livestock Crop yield improvement from intensification oftencoincide (see Figure 2.17). has substantial environmental costs (Pingali and As a result of economies of scale, indus- Heisey,1999; Tilman et al., 2001). Agriculturaltrial livestock production generates substantially intensification can have negative consequenceslower income per unit of output than smallhold- at various levels:er farms and benefits go to fewer producers. • local: increased erosion, lower soil fertility,Furthermore, economic returns and spillover and reduced biodiversity;effects occur in the, generally, already better-off • regional: pollution of ground water and eutro-urban areas. The shift towards such production phication of rivers and lakes; andhas thus, on balance, a largely negative effect on • global: impacts on atmospheric constituents,rural development (de Haan et al., 2001). climate and ocean waters.Main global environment concerns associated Biological consequences at the with contamination in peri-urban environments agro-ecosystem levelinclude climate change through gaseous emis- A key aspect of intensive agriculture is thesions from animal waste management, water high specialization of production, often leadingresources depletion through pollution of sur- to monoculture with tight control of unwantedface and groundwater, and biodiversity erosion “weed” species. The reduced diversity of thethrough water and soil pollution. These issues plant community affects the pest complex as70
    • Livestock in geographic transition Box 2.4 Livestock waste management in East Asia Nowhere have the rapid growth of livestock produc- addresses environmental threats by developing tion, and its impact on the environment, been more policies to balance the location of livestock produc- evident than in parts of Asia. During the decade tion operations with land resources and to encour- of the 1990s alone, production of pigs and poultry age the use of manure and other nutrients by crop almost doubled in China, Thailand and Viet Nam. farmers. It will also set up pilot farms to demon- By 2001, these three countries alone accounted for strate good manure management techniques. more than half the pigs and one-third of the chick- Pollutants from all three countries threaten the ens in the entire world. South China Sea. But the nature of livestock opera- Not surprisingly, these same countries have also tions differs markedly among the countries. In experienced rapid increases in pollution associated Thailand, three-quarters of pigs are now produced with concentrations of intensive livestock produc- on large, industrial farms with more than 500 ani- tion. Pig and poultry operations concentrated in mals. In Viet Nam, on the other hand, very small coastal areas of China, Viet Nam and Thailand are producers with just three or four pigs account for emerging as the major source of nutrient pollution 95 percent of production. While half of the pigs in of the South China Sea. Along much of the densely Guangdong are still produced in operations with populated coast, the pig density exceeds 100 ani- fewer than 100 animals, large-scale industrial mals per km2 and agricultural lands are over- operations are growing rapidly. Almost one-quarter loaded with huge nutrient surpluses (see Map 4.1, of the pigs in Guangdong are produced on farms Chapter 4). Run-off is severely degrading seawater with more than 3 000 animals. and sediment quality in one of the world’s most The LWMEAP project outlines policies at both biologically diverse shallow-water marine areas, the national and local levels. At the national level, causing “red tides” and threatening fragile coastal, the project stresses the need for inter-agency marine habitats including mangroves, coral reefs cooperation to develop effective and realistic regu- and sea grasses. lations on environmental monitoring and manure The related booms in production and pollution management and to undertake spatial planning for have kindled plans for one of the most comprehen- the location of future livestock development to cre- sive efforts to forge an effective policy response ate the conditions for better recycling of effluents. – the Livestock Waste Management in East Asia As a key tool for shaping and implementing policy Project (LWMEAP) – which has been prepared at the local level, LWMEAP provides support to the with the governments of China, Thailand and Viet development of codes of practice adapted to the Nam by FAO and the inter-institutional Livestock, specific contexts. Environment and Development Initiative (LEAD – www.lead.virtualcentre.org), under a grant from The Global Environment Facility. The project Source: FAO (2004d).well as soil invertebrates and micro-organisms, al., 1997). The immediate reaction is to increasewhich in turn affects plant growth and health. pesticide applications. As a result, pesticideThe low diversity of monocultural agricultural diffusion along wildlife food chains and pesti-systems typically results in greater crop losses cide resistance has become an acute problemfrom insect pests that are less diverse but more worldwide.abundant (Tonhasca and Byrne, 1994; Matson et The effects of monoculture on the soil biotic 71
    • Livestock’s long shadowcommunity are less evident, as is effect of these though it stabilized thereafter (FAO, 2006b – seechanges on agro-ecosystems. Studies of key Table 1, Annex 2). The stabilization of fertilizerorganisms however show that reduction in diver- consumption at the global level results from thesity of soil biota under agricultural practice may balance of consumption, increasing in devel-substantially alter the decomposition process oping countries and decreasing in developedand nutrient availability in the soil (Matson et countries.al., 1999). The uptake of fertilizer nutrients by crops is limited. A significant share of P is carried awayChanges in natural resources by runoff, while Matson et al. (1999) estimateOrganic matter is a critical component of soils. It that about 40 to 60 percent of the N that isprovides the substrate for nutrient release, and applied to crops is left in the soil or lost by leach-plays a critical role in soil structure, increasing ing. The leaching of nitrate from soils to waterwater holding capacity and reducing erosion. For systems leads to increased concentrations inintensive cropland in temperate zone agricul- drinking water and contamination of ground andture, soil organic matter losses are most rapid surface water systems, which threaten humanduring the first 25 years of cultivation, with typi- health and natural ecosystems. In particular,cal losses of 50 percent of the original C. In tropi- eutrophication of waterways and coastal areascal soils, however, such losses may occur within kills aquatic organisms and eventually causesfive years after conversion (Matson et al., 1999). biodiversity losses.In addition to local impacts, the large amounts of N fertilization, both chemical and organic, alsoCO2 released in decomposition of organic matter leads to increased emissions of gases such asgreatly contribute to climate change. nitrogen oxides (NOx), nitrous oxide (N2O) and Increasing yields also require more water. Irri- ammonia (NH3). Klimont (2001) found that emis-gated land expanded at the rate of 2 percent per sions of ammonia in China increased from 9.7year between 1961 and 1991, and at 1 percent Tg in 1990 to 11.7 Tg in 1995 and are projectedper year during the past decade (FAO, 2006b to rise to nearly 20 Tg NH3 in 2030. The largest– see Table 1, Annex 2). This trend has dramatic single source of emissions is the use of urea andconsequences on the water resources. Over- ammonium bicarbonate ‑ the key fertilizers inpumping is a serious concern in many regions, China.especially where feedcrop species are culti- Nitrogen oxide and ammonia may be trans-vated outside their suitable agro-ecozone (e.g. ported and deposited to downwind ecosystems.maize in most parts of Europe), and the use of This deposition can lead to soil acidification,non-renewable water resources (fossil water) is eutrophication of natural ecosystems and shiftsfrequent. Irrigation often takes place in a context in species diversity, with effects on predator andof water scarcity, and this is expected to worsen parasite systems (Galloway et al.,1995). N depo-as competition for withdrawals increases with sition, mostly related to agriculture, is expectedhuman population growth, development and cli- to increase dramatically over coming decades.mate change. The emission of nitrous oxides also impacts global climate, contributing to global warmingHabitat deterioration ‑ indeed the global warming potential of N2O isIntensification of agricultural production has 310 times greater than for carbon dioxide.been accompanied by large increases in global Finally, intensive agriculture land use impactsnitrogen (N) and phosphorus (P) fertilization. wildlife habitats. Monoculture areas offer littleChemical fertilizer consumption grew at 4.6 per- food or shelter to wildlife. Wild fauna is thuscent per year over the 1961 to 1991 period, mostly absent from such intensive cropland.72
    • Livestock in geographic transition Box 2.5 Livestock production systems and erosion in the United States Soil erosion is regarded as one of the most impor- Table 2.13 tant environmental problems in the United States. Contribution of livestock to soil erosion on In the last 200 years, the United States has probably agricultural lands in the United States lost at least one-third of its topsoil (Barrow, 1991). Erosion on cropped land Although erosion rates declined between 1991 and Total erosion on cropped land (million tonnes/year) 1 620.8 2000, average erosion rates in 2001, at 12.5 tonnes Average water and per hectare per year (see Table 2.13), were still wind cumulated erosion rate (tonnes/ha/year) 12.5 above the established sustainable soil loss rate of Total arable land for feed production (million ha) 51.6 11 tonnes per hectare per year (Barrow, 1991). Total erosion associated with feed production The rate and severity of erosion is site specific on cropped land (million tonnes/year) 648.3 and depends largely on local conditions and soil As percentage of total erosion on cropped land 40 types. However, the link with livestock production Erosion on pastureland is compelling. About 7 percent of the agricultural Average water and land (2001) in the United States is devoted to the wind cumulated erosion rate (tonnes/ha/year) 2 production of animal feed. Livestock production Total pastureland (million ha) 234 can be said to be directly or indirectly responsible Total erosion on pastureland (million tonnes/year) 524.2 for a significant proportion of the soil erosion in Erosion on agricultural land (crop and pasture) the United States. A careful assessment of erosion Total erosion from Agricultural land on crop and pasture lands suggests that livestock (million tonnes/year) 2 145.0 are the major contributor to soil erosion on agri- Total erosion associated with cultural lands, accounting for 55 percent of the livestock production (million tonnes/year) 1 172.5 total soil mass eroded every year (Table 2.13). Of As percentage of total erosion on agricultural land 55 this eroded mass, around 40 percent will end up Source: USDA/NASS (2001); FAO (2006b). in water resources. The rest will be deposited on other land sites. Nevertheless considering the major importance of the role of agriculture land in water contamina- tion by sediments in the United States, we can rea- sonably assume that livestock production systems are the major source of sediment contamination of freshwater resources.Furthermore, intensively cropped parcels often aged. To sustain cereal productivity growth whilerepresent a barrier to wildlife movements, lead- conserving the resource base demands that pro-ing to ecosystem fragmentation. As a conse- duction increases should be achieved with lessquence, Pingali and Heisey (1999) suggest that than proportionate increases in chemical inputs.meeting the long-term demand requirements Recent advances in fertilizer and pesticide for-for food, and in particular cereals will require mulae, as well as in technology and techniquesmore than a shift in the yield frontier. It will also for their efficient use, may help in meeting theserequire fundamental changes in the way fertil- objectives (Pingali and Heisey, 1999).izers and pesticides are used and soil is man- 73
    • Livestock’s long shadowSoil erosion Main global environment concerns associatedErosion rates greatly vary depending on local with intensive feedcrop agriculture include cli-conditions and it is often difficult to compare mate change, through gaseous emissions fromlocal data. Erosion rates are influenced by sev- fertilizer applications and the decomposition oferal factors including soil structure, landscape organic matter in the soil, depletion of watermorphology, vegetation cover, rainfall and wind resources through pollution and withdraw-levels, land use and land management includ- als, and erosion of biodiversity through habitating method, timing and frequency of cultivation destruction and water and soil pollution. These(Stoate et al., 2001) (see Box 2.5). As the worst issues will be reviewed in Chapter 3, 4 and 5,erosion is usually caused by runoff water, ero- respectively.sion tends to increase as infiltration decreases.Any activity that modifies significantly the infil- 2.6 Conclusionstration process has an impact on the erosion Today, the livestock sector is a major land user,process. spanning more than 3.9 billion hectares, repre- Croplands, especially under intensive agri- senting about 30 percent of the world’s surfaceculture, are generally more prone to erosion land area. The intensity with which the sectorthan other land uses. Major factors that contrib- uses land is however extremely variable. Ofute to increased erosion rates within croplands the 3.9 billion hectares, 0.5 are crops, gener-include: ally intensively managed (Section 2.3); 1.4 are• removal of the natural vegetation that binds pasture with relatively high productivity and; the soil, protects it from the wind and improves the remaining 2.0 billion hectares are extensive infiltration; pastures with relatively low productivity (Table• inappropriate cultivation practices; 4, Annex 2). The sector is the first agricultural• the mechanical impact of heavy agricultural land user, accounting for about 78 percent of machines; and agricultural land and as much as 33 percent• depletion of the natural soil fertility. of the cropland. Despite the fact that intensive, ”landless” systems have been responsible for Barrow (1991) reviewed the magnitude of ero- most of the sector’s growth, the influence thesion from cropland in various countries. As the sector has on the cropland is still substantial,methodologies used for assessing the erosion and environmental issues associated to livestockprocess are not standardized it is difficult to production could not be comprehensively appre-compare the different measures. He noted that hended without including the crop sector in ourerosion levels can be extremely severe in some analysis.cases resulting in the loss of more than 500 As the livestock sector develops, however,tonnes of soil per hectare per year (observed in its land-size requirements grow and the sectorEcuador and Côte d’Ivoire). As a reference, a loss undergoes a geographical transition involvingof 50 tonnes per hectare per year amounts to a changes in land-use intensity and geographicalloss of depth of about 3 mm/yr off a soil profile. distribution patterns.This is enough to affect agriculture in quite ashort time if the top soil is shallow. There is little Intensification slows the spread of livestock-agreement in the literature on permissible rates related land useof erosion but erosion levels of 0.1 to 0.2 mm per The first aspect of this transition is land-useyear are often considered as acceptable (Barrow, intensification. It relates to feed supply, the main1991). purpose for which the sector uses land (either directly as pasture or indirectly as feedcrops).74
    • Livestock in geographic transitionFeedcrops and cultivated pastures intensify in trends. In the EU (Figure 2.19) and more gener-areas with developed transport infrastructure, ally in OECD countries, the growth of meat andstrong institutions and high agro-ecological suit- milk production happened at the same timeability. Figure 2.18 shows the marked difference as a reduction in the area dedicated to pasturein growth rates between the global areas dedi- and feedcrops. This was predominantly achievedcated to pasture and feed production, compared through improved feed-conversion ratios, butto the meat and milk outputs of the sector. This part of the reduction in local feedcrop area wasincreasing productivity is the consequence of also compensated by feed imports, in particularstrong intensification of the sector on a global from South America. Indeed, the comparablescale. The shift from ruminant species to mono- trends in South America (Figure 2.20) show agastric species fed on improved diets plays a relatively stronger growth of feedcrop areas.critical role in this process. Rapid development of a regional intensive live- The growth in demand for livestock products stock sector fuelled the feed production industrywill probably still play a dominant role over the but exports were responsible for extra growth.next decades and lead to a net increase in the Feedcrops grew especially rapidly in the 1970sarea dedicated to livestock, despite the intensi- and late 1990s, when first developed countriesfication trend. Extensive pastures and feedcrop and then developing countries engaged in live-production will expand into natural habitats with stock industrialization and started importinglow opportunity cost. It is, however, likely that protein feed.the bulk of pasture and feedcrop spread has This is for example currently under way inalready occurred, and that the intensification East and Southeast Asia (Figure 2.21), whereprocess will soon overcome the trend for area production has grown dramatically faster thanexpansion, leading to an eventual net decrease the area under feedcrops and pasture (which hasin the area under pasture and feedcrops. remained stable). This difference in growth rates There are regional variations to these global has been achieved by importing feed resources, Figure 2.18 Global trends in land-use area Figure 2.19 Trends in land-use area for for livestock production and livestock production and local total production of meat and milk supply of meat and milk – EU-15 350 250 300 200 250 Index: 1961=100 Index: 1961=100 150 200 100 150 100 50 50 0 1961 1966 1971 1976 1981 1986 1991 1996 2001 1961 1966 1971 1976 1981 1986 1991 1996 2001 Pasture Milk production Pasture Milk production Arable land for feed crops Meat production Arable land for feed crops Meat production Source: FAO (2006b). Source: FAO (2006b). 75
    • Livestock’s long shadow Figure 2.20 Trends in land-use area for Production shifts to areas of feed resources or livestock production and local lower costs supply of meat and milk – South America The second feature of livestock’s geographical transition lies in the changing spatial distribution 450 of production. Production and consumption no 400 longer coincide, as most consumption is located 350 in urban centres, far from the feed resources. 300 Index: 1961=100 The livestock sector has adapted to this new 250 configuration by splitting up the commodity 200 chain and locating each specialized production 150 or processing segment where production costs 100 50 are minimized. With the development of trans- 0 port infrastructure, shipment of animal products 1961 1966 1971 1976 1981 1986 1991 1996 2001 is becoming relatively cheap in comparison with Pasture Milk production other production costs. The trend towards more Arable land for feed crops Meat production processed foods further contributes to reducing Source: FAO (2006b). transport costs. Livestock production, therefore, moves closer to feed resources, or to places where the policy context (tax regime, labour Figure 2.21 Trends in land-use area for standards, environmental standards), as well as livestock production and local access to services or disease conditions, mini- supply of meat and milk – East and Southeast Asia (excluding China) mize production costs. In essence, livestock are thus moving from a “default land user” strategy 900 (i.e. as the only way to harness biomass from 800 marginal lands, residues and interstitial areas) 700 to an “active land user” strategy (i.e. competing Index: 1961=100 600 with other sectors for the establishment of feed- 500 crops, intensive pasture and production units). 400 300 Paying the environmental price 200 100 This process leads to efficiency gains in the use of 0 resources. However, it usually develops within a 1961 1966 1971 1976 1981 1986 1991 1996 2001 context of environmental and social externalities Pasture Meat production that are mostly not addressed, and inadequate Arable land for feed crops Milk - excluding butter pricing of resources on the basis of private rath- Source: FAO (2006b). er than social costs. As a consequence, changes in livestock geography are associated with sub- stantial environmental impacts. For example, the private costs of transport are distortedly lowand also through a rapid intensification of the and do not reflect social costs. The expansionlivestock industry involving breed improvement, and intensification of crop agriculture is associ-improved animal husbandry and a shift to poultry ated with profound land degradation problems.(the methodology developed to estimate land use The continuous expansion of agriculture intoby livestock, as well as complementary results natural ecosystems causes climate change andare presented in Annex 3.1). biodiversity loss. The disconnection of livestock76
    • Livestock in geographic transitionproduction from its feed base creates inadequate ing the inherent trade-offs between meetingconditions for good waste management prac- the current demand for animal-derived foods,tices, which often cause soil and water pollution and maintaining the capacity of ecosystems toas well as greenhouse gas emissions. provide goods and services in the future (Foley On current trends, the ecological footprint et al., 2005). Ultimately, reaching a sustainableof the livestock sector will increase because of balance will require adequate pricing of naturalexpansion of land use and land degradation. resources, the internalization of externalitiesConfronting the global environmental challenges and the preservation of key ecosystems.of land use will require assessing and manag- 77
    • 03
    • Livestock’s role in climate change and air pollution 3.1 Issues and trends tribution of the livestock sector as a whole to The atmosphere is fundamental to life on earth. these processes is not well known. At virtually Besides providing the air we breathe it regulates each step of the livestock production process temperature, distributes water, it is a part of substances contributing to climate change or air key processes such as the carbon, nitrogen and pollution, are emitted into the atmosphere, or oxygen cycles, and it protects life from harmful their sequestration in other reservoirs is ham- radiation. These functions are orchestrated, in a pered. Such changes are either the direct effect fragile dynamic equilibrium, by a complex phys- of livestock rearing, or indirect contributions ics and chemistry. There is increasing evidence from other steps on the long road that ends with that human activity is altering the mechanisms the marketed animal product. We will analyse of the atmosphere. the most important processes in their order in In the following sections, we will focus on the the food chain, concluding with an assessment anthropogenic processes of climate change and of their cumulative effect. Subsequently a num- air pollution and the role of livestock in those ber of options are presented for mitigating the processes (excluding the ozone hole). The con- impacts.
    • Livestock’s long shadowClimate change: trends and prospectsAnthropogenic climate change has recentlybecome a well established fact and the result-ing impact on the environment is already beingobserved. The greenhouse effect is a key mech-anism of temperature regulation. Without it,the average temperature of the earth’s surface © FAO/7398/F. Bottswould not be 15ºC but -6ºC. The earth returnsenergy received from the sun back to space byreflection of light and by emission of heat. A partof the heat flow is absorbed by so-called green-house gases, trapping it in the atmosphere. Cracked clay soil – Tunisia 1970The principal greenhouse gases involved in thisprocess include carbon dioxide (CO2), methane(CH4) nitrous oxide (N2O) and chlorofluorocar- present-day concentrations of CO2 and CH4 thatbons. Since the beginning of the industrial period are unprecedented over the last 650 000 years ofanthropogenic emissions have led to an increase earth history (Siegenthaler et al., 2005).in concentrations of these gases in the atmo- Global warming is expected to result in chang-sphere, resulting in global warming. The average es in weather patterns, including an increase intemperature of the earth’s surface has risen by global precipitation and changes in the severity0.6 degrees Celsius since the late 1800s. or frequency of extreme events such as severe Recent projections suggest that average storms, floods and droughts.temperature could increase by another 1.4 to Climate change is likely to have a significant5.8 °C by 2100 (UNFCCC, 2005). Even under impact on the environment. In general, thethe most optimistic scenario, the increase in faster the changes, the greater will be the riskaverage temperatures will be larger than any of damage exceeding our ability to cope with thecentury-long trend in the last 10 000 years of consequences. Mean sea level is expected tothe present-day interglacial period. Ice-core- rise by 9–88 cm by 2100, causing flooding of low-based climate records allow comparison of the lying areas and other damage. Climatic zonescurrent situation with that of preceding inter- could shift poleward and uphill, disrupting for-glacial periods. The Antarctic Vostok ice core, ests, deserts, rangelands and other unmanagedencapsulating the last 420 000 years of Earth ecosystems. As a result, many ecosystems willhistory, shows an overall remarkable correlation decline or become fragmented and individualbetween greenhouse gases and climate over species could become extinct (IPCC, 2001a).the four glacial-interglacial cycles (naturally The levels and impacts of these changes willrecurring at intervals of approximately 100 000 vary considerably by region. Societies will faceyears). These findings were recently confirmed new risks and pressures. Food security is unlike-by the Antarctic Dome C ice core, the deepest ly to be threatened at the global level, but someever drilled, representing some 740 000 years regions are likely to suffer yield declines of major‑ the longest, continuous, annual climate record crops and some may experience food shortagesextracted from the ice (EPICA, 2004). This con- and hunger. Water resources will be affected asfirms that periods of CO2 build-up have most precipitation and evaporation patterns changelikely contributed to the major global warming around the world. Physical infrastructure willtransitions at the earth’s surface. The results be damaged, particularly by the rise in sea-levelalso show that human activities have resulted in and extreme weather events. Economic activi-80
    • Livestock’s role in climate change and air pollution Box 3.1 The Kyoto Protocol In 1995 the UNFCCC member countries began ity to countries that are over their targets. This negotiations on a protocol – an international agree- so-called “carbon market” is both flexible and real- ment linked to the existing treaty. The text of the istic. Countries not meeting their commitments so-called Kyoto Protocol was adopted unanimously will be able to “buy” compliance but the price may in 1997; it entered into force on 16 February 2005. be steep. Trades and sales will deal not only with The Protocol’s major feature is that it has man- direct greenhouse gas emissions. Countries will datory targets on greenhouse-gas emissions for get credit for reducing greenhouse gas totals by those of the world’s leading economies that have planting or expanding forests (“removal units”) and accepted it. These targets range from 8 percent for carrying out “joint implementation projects” below to 10 percent above the countries’ individual with other developed countries – paying for proj- 1990 emissions levels “with a view to reducing their ects that reduce emissions in other industrialized overall emissions of such gases by at least 5 per- countries. Credits earned this way may be bought cent below existing 1990 levels in the commitment and sold in the emissions market or “banked” for period 2008 to 2012”. In almost all cases – even future use. those set at 10 percent above 1990 levels – the The Protocol also makes provision for a “clean limits call for significant reductions in currently development mechanism,” which allows industrial- projected emissions. ized countries to pay for projects in poorer nations To compensate for the sting of these binding to cut or avoid emissions. They are then awarded targets, the agreement offers flexibility in how credits that can be applied to meeting their own countries may meet their targets. For example, emissions targets. The recipient countries benefit they may partially compensate for their industrial, from free infusions of advanced technology that for energy and other emissions by increasing “sinks” example allow their factories or electrical generat- such as forests, which remove carbon dioxide from ing plants to operate more efficiently – and hence the atmosphere, either on their own territories or at lower costs and higher profits. The atmosphere in other countries. benefits because future emissions are lower than Or they may pay for foreign projects that result they would have been otherwise. in greenhouse-gas cuts. Several mechanisms have been established for the purpose of emissions trading. The Protocol allows countries that have unused emissions units to sell their excess capac- Source: UNFCCC (2005).ties, human settlements, and human health will 2.5°C could reduce global food supplies andexperience many direct and indirect effects. The contribute to higher food prices. The impact onpoor and disadvantaged, and more generally the crop yields and productivity will vary consider-less advanced countries are the most vulnerable ably. Some agricultural regions, especially into the negative consequences of climate change the tropics and subtropics, will be threatened bybecause of their weak capacity to develop coping climate change, while others, mainly in temper-mechanisms. ate or higher latitudes, may benefit. Global agriculture will face many challenges The livestock sector will also be affected. Live-over the coming decades and climate change stock products would become costlier if agricul-will complicate these. A warming of more than tural disruption leads to higher grain prices. In 81
    • Livestock’s long shadowgeneral, intensively managed livestock systems industrial times (Table 3.1), although the rate ofwill be easier to adapt to climate change than increase has been declining recently. It is emittedwill crop systems. Pastoral systems may not from a variety of natural and human-influencedadapt so readily. Pastoral communities tend sources. The latter include landfills, natural gasto adopt new methods and technologies more and petroleum systems, agricultural activities,slowly, and livestock depend on the productiv- coal mining, stationary and mobile combustion,ity and quality of rangelands, some of which wastewater treatment and certain industrialmay be adversely affected by climate change. In process (US-EPA, 2005). The IPCC has estimatedaddition, extensive livestock systems are more that slightly more than half of the current CH4susceptible to changes in the severity and distri- flux to the atmosphere is anthropogenic (IPCC,bution of livestock diseases and parasites, which 2001b). Total global anthropogenic CH4 is esti-may result from global warming. mated to be 320 million tonnes CH4/yr, i.e. 240 As the human origin of the greenhouse effect million tonnes of carbon per year (van Aardennebecame clear, and the gas emitting factors were et al., 2001). This total is comparable to the totalidentified, international mechanisms were cre- from natural sources (Olivier et al., 2002).ated to help understand and address the issue. Nitrous oxide, a third greenhouse gas withThe United Nations Framework Convention on important direct warming potential, is presentClimate Change (UNFCCC) started a process of in the atmosphere in extremely small amounts.international negotiations in 1992 to specifically However, it is 296 times more effective than car-address the greenhouse effect. Its objective is to bon dioxide in trapping heat and has a very longstabilize greenhouse gas concentrations in the atmospheric lifetime (114 years).atmosphere within an ecologically and economi- Livestock activities emit considerable amountscally acceptable timeframe. It also encourages of these three gases. Direct emissions from live-research and monitoring of other possible envi- stock come from the respiratory process of allronmental impacts, and of atmospheric chem- animals in the form of carbon dioxide. Rumi-istry. Through its legally binding Kyoto Protocol, nants, and to a minor extent also monogastrics,the UNFCCC focuses on the direct warmingimpact of the main anthropogenic emissions(see Box 3.1). This chapter concentrates on Table 3.1describing the contribution of livestock produc- Past and current concentration of importanttion to these emissions. Concurrently it provides greenhouse gasesa critical assessment of mitigation strategies Gas Pre-industrial Current Global concentration tropospheric warming such as emissions reduction measures related (1 750) concentration potential*to changes in livestock farming practices. The direct warming impact is highest for Carbon dioxide (CO2) 277 ppm 382 ppm 1carbon dioxide simply because its concentra- Methane (CH4) 600 ppb 1 728 ppb 23tion and the emitted quantities are much higher Nitrous oxide (N2O) 270–290 ppb 318 ppb 296than that of the other gases. Methane is the Note: ppm = parts per million; ppb = parts per billion; pptsecond most important greenhouse gas. Once = parts per trillion; *Direct global warming potential (GWP) relative to CO2 for a 100 year time horizon. GWPs are a simpleemitted, methane remains in the atmosphere way to compare the potency of various greenhouse gases. Thefor approximately 9–15 years. Methane is about GWP of a gas depends not only on the capacity to absorb and reemit radiation but also on how long the effect lasts. Gas21 times more effective in trapping heat in the molecules gradually dissociate or react with other atmosphericatmosphere than carbon dioxide over a 100- compounds to form new molecules with different radiative properties.year period. Atmospheric concentrations of CH4 Source: WRI (2005); 2005 CO2: NOAA (2006); GWPs: IPCChave increased by about 150 percent since pre- (2001b).82
    • Livestock’s role in climate change and air pollutionemit methane as part of their digestive process, air pollutants carried by winds can affect placeswhich involves microbial fermentation of fibrous far (hundreds of kilometres if not further) fromfeeds. Animal manure also emits gases such as the points where they are released.methane, nitrous oxides, ammonia and carbon The stinging smell that sometimes stretchesdioxide, depending on the way they are produced over entire landscapes around livestock facilities(solid, liquid) and managed (collection, storage, is partly due to ammonia emission.2 Ammoniaspreading). volatilization (nitrified in the soil after deposition) Livestock also affect the carbon balance of is among the most important causes of acidify-land used for pasture or feedcrops, and thus ing wet and dry atmospheric deposition, and aindirectly contribute to releasing large amounts large part of it originates from livestock excreta.of carbon into the atmosphere. The same hap- Nitrogen (N) deposition is higher in northernpens when forest is cleared for pastures. In Europe than elsewhere (Vitousek et al., 1997).addition, greenhouse gases are emitted from Low-level increases in nitrogen deposition asso-fossil fuel used in the production process, from ciated with air pollution have been implicated infeed production to processing and marketing of forest productivity increases over large regions.livestock products. Some of the indirect effects Temperate and boreal forests, which historicallyare difficult to estimate, as land use related have been nitrogen-limited, appear to be mostemissions vary widely, depending on biophysical affected. In areas that become nitrogen-satu-factors as soil, vegetation and climate as well as rated, other nutrients are leached from the soil,on human practices. resulting eventually in forest dieback – coun- teracting, or even overwhelming, any growth-Air pollution: acidification and nitrogen enhancing effects of CO2 enrichment. Researchdeposition shows that in 7–18 percent of the global area ofIndustrial and agricultural activities lead to the (semi-) natural ecosystems, N deposition sub-emission of many other substances into the stantially exceeds the critical load, presentingatmosphere, many of which degrade the qual- a risk of eutrophication and increased leachingity of the air for all terrestrial life.1 Important (Bouwman and van Vuuren, 1999) and althoughexamples of air pollutants are carbon monoxide, knowledge of the impacts of N deposition at thechlorofluorocarbons, ammonia, nitrogen oxides, global level is still limited, many biologicallysulphur dioxide and volatile organic compounds. valuable areas may be affected (Phoenix et al., In the presence of atmospheric moisture and 2006). The risk is particularly high in Westernoxidants, sulphur dioxide and oxides of nitro- Europe, in large parts of which over 90 percentgen are converted to sulphuric and nitric acids. of the vulnerable ecosystems receive more thanThese airborne acids are noxious to respiratory the critical load of nitrogen. Eastern Europesystems and attack some materials. These air and North America are subject to medium riskpollutants return to earth in the form of acid levels. The results suggest that even a numberrain and snow, and as dry deposited gases and of regions with low population densities, suchparticles, which may damage crops and forests as Africa and South America, remote regionsand make lakes and streams unsuitable for fish of Canada and the Russian Federation, mayand other plant and animal life. Though usually become affected by N eutrophication.more limited in its reach than climate change, 2 Other important odour-producing livestock emissions are1 The addition of substances to the atmosphere that result in volatile organic compounds and hydrogen sulphide. In fact, direct damage to the environment, human health and quality well over a hundred gases pass into the surroundings of of life is termed air pollution. livestock operations (Burton and Turner, 2003; NRC, 2003). 83
    • Livestock’s long shadow3.2 Livestock in the carbon cycle divided into two categories: the geological, whichThe element carbon (C) is the basis for all life. operates over large time scales (millions ofIt is stored in the major sinks shown in Figure years), and the biological/physical, which oper-3.1 which also shows the relative importance of ates at shorter time scales (days to thousandsthe main fluxes. The global carbon cycle can be of years). Figure 3.1 The present carbon cycle Atmosphere 750 Plant growth 60 61 Change in 90 90 and decay land use Fossil Fuel 1.5 5.5 emissions Terrestrial 0.5 vegetation 540–610 Soils and organic matter 1 600 Marine organism Dissolved 3 organic carbon 700 50 40 6 Surface water 4 1 020 100 92 Marine sediments, sedimentary rocks and fossil fuel 66 000 000–100 000 000 Intermediate and deep water 38 000–40 000 Note: Volumes and exchanges in billion tonnes of carbon. The figures present annual averages over the period 1980 to 1989. The component cycles are simplified. Evidence is accumulating that many of the fluxes can significantly change from year to year. Although this figure conveys a static view, in the real world the carbon system is dynamic and coupled to the climate system on seasonal, interannual and decadal timescales. Source: Adapted from UNEP-GriD Vital Climate Graphics (available at www.grida.no/climate/vital/13.htm).84
    • Livestock’s role in climate change and air pollution Ecosystems gain most of their carbon dioxide greater than the amount of carbon released tofrom the atmosphere. A number of autotro- the atmosphere by fossil fuel burning. But thephic organisms3 such as plants have special- anthropogenic flows are one-way only, and thisized mechanisms that allow for absorption of characteristic is what leads to imbalance inthis gas into their cells. Some of the carbon in the global carbon budget. Such emissions areorganic matter produced in plants is passed to either net additions to the biological cycle, orthe heterotrophic animals that eat them, which they result from modifications of fluxes withinthen exhale it into the atmosphere in the form of the cycle.carbon dioxide. The CO2 passes from there intothe ocean by simple diffusion. Livestock’s contribution to the net release of Carbon is released from ecosystems as car- carbonbon dioxide and methane by the process of Table 3.2 gives an overview of the various carbonrespiration that takes place in both plants and sources and sinks. Human populations, eco-animals. Together, respiration and decomposi- nomic growth, technology and primary energytion (respiration mostly by bacteria and fungi requirements are the main driving forces ofthat consumes organic matter) return the bio- anthropogenic carbon dioxide emissions (IPCClogically fixed carbon back to the atmosphere. – special report on emission scenarios).The amount of carbon taken up by photosyn- The net additions of carbon to the atmospherethesis and released back to the atmosphere by are estimated at between 4.5 and 6.5 billionrespiration each year is 1 000 times greater than tonnes per year. Mostly, the burning of fossil fuelthe amount of carbon that moves through the and land-use changes, which destroy organicgeological cycle on an annual basis. carbon in the soil, are responsible. Photosynthesis and respiration also play The respiration of livestock makes up only aan important role in the long-term geological very small part of the net release of carbon thatcycling of carbon. The presence of land vegeta-tion enhances the weathering of rock, leading tothe long-term—but slow—uptake of carbon diox- Table 3.2ide from the atmosphere. In the oceans, some of Atmospheric carbon sources and sinksthe carbon taken up by phytoplankton settles to Factor Carbon flux (billion tonnes C per year)the bottom to form sediments. During geologicalperiods when photosynthesis exceeded respira- Into the Out of the atmosphere atmospheretion, organic matter slowly built up over mil-lions of years to form coal and oil deposits. The Fossil fuel burning 4–5 amounts of carbon that move from the atmo- Soil organic mattersphere, through photosynthesis and respiration, oxidation/erosion 61–62 back to the atmosphere are large and produce Respiration fromoscillations in atmospheric carbon dioxide con- organisms in biosphere 50centrations. Over the course of a year, these Deforestation 2 biological fluxes of carbon are over ten times Incorporation into biosphere through photosynthesis 110 Diffusion into oceans 2.53 Net 117–119 112.5 Autotrophic organisms are auto-sufficient in energy sup- ply, as distinguished from parasitic and saprophytic; het- Overall annual net increase erotrophic organisms require an external supply of energy in atmospheric carbon +4.5–6.5 contained in complex organic compounds to maintain their Source: available at www.oznet.ksu.edu/ctec/Outreach/sci- existence. ence_ed2.htm 85
    • Livestock’s long shadowcan be attributed to the livestock sector. Much corresponding cropland, especially in the casemore is released indirectly by other channels of high-energy crops such as maize, used in theincluding: production of concentrate feed. The gaseous• burning fossil fuel to produce mineral fertiliz- emissions caused by fertilizer manufacturing ers used in feed production; should, therefore, be considered among the• methane release from the breakdown of ferti- emissions for which the animal food chain is lizers and from animal manure; responsible.• land-use changes for feed production and for About 97 percent of nitrogen fertilizers are grazing; derived from synthetically produced ammonia• land degradation; via the Haber-Bosch process. For economic and• fossil fuel use during feed and animal produc- environmental reasons, natural gas is the fuel tion; and of choice in this manufacturing process today.• fossil fuel use in production and transport of Natural gas is expected to account for about processed and refrigerated animal products. one-third of global energy use in 2020, compared with only one-fifth in the mid-1990s (IFA, 2002). In the sections that follow we shall look at The ammonia industry used about 5 percent ofthese various channels, looking at the various natural gas consumption in the mid-1990s. How-stages of livestock production. ever, ammonia production can use a wide range of energy sources. When oil and gas supplies3.2.1 Carbon emissions from feed eventually dwindle, coal can be used, and coalproduction reserves are sufficient for well over 200 years atFossil fuel use in manufacturing fertilizer may current production levels. In fact 60 percent ofemit 41 million tonnes of CO2 per year China’s nitrogen fertilizer production is currentlyNitrogen is essential to plant and animal life. based on coal (IFA, 2002). China is an atypi-Only a limited number of processes, such as cal case: not only is its N fertilizer productionlightning or fixation by rhizobia, can convert it based on coal, but it is mostly produced in smallinto reactive form for direct use by plants and and medium-sized, relatively energy-inefficient,animals. This shortage of fixed nitrogen has his- plants. Here energy consumption per unit of Ntorically posed natural limits to food production can run 20 to 25 percent higher than in plantsand hence to human populations. of more recent design. One study conducted by However, since the third decade of the twen- the Chinese government estimated that energytieth century, the Haber-Bosch process has consumption per unit of output for small plantsprovided a solution. Using extremely high pres- was more than 76 percent higher than for largesures, plus a catalyst composed mostly of iron plants (Price et al., 2000).and other critical chemicals, it became the pri- Before estimating the CO2 emissions relatedmary procedure responsible for the production to this energy consumption, we should try toof chemical fertilizer. Today, the process is used quantify the use of fertilizer in the animal foodto produce about 100 million tonnes of artificial chain. Combining fertilizer use by crop for thenitrogenous fertilizer per year. Roughly 1 percent year 1997 (FAO, 2002) with the fraction of theseof the world’s energy is used for it (Smith, 2002). crops used for feed in major N fertilizer con- As discussed in Chapter 2, a large share of suming countries (FAO, 2003) shows that animalthe world’s crop production is fed to animals, production accounts for a very substantial shareeither directly or as agro-industrial by-products. of this consumption. Table 3.3 gives examples forMineral N fertilizer is applied to much of the selected countries.486
    • Livestock’s role in climate change and air pollutionTable 3.3 crop highest in nitrogen fertilizer consumptionChemical fertilizer N used for feed and pastures in in 18 of the 66 maize producing countries ana-selected countries lysed (FAO, 2002). In 41 of these 66 countriesCountry Share of Absolute maize is among the first three crops in terms of total N consumption amount nitrogen fertilizer consumption. The projected (percentage) (1 000 tonnes/year) production of maize in these countries showUSA 51 4 697 that its area generally expands at a rate inferiorChina 16 2 998 to that of production, suggesting an enhancedFrance* 52 1 317 yield, brought about by an increase in fertilizerGermany* 62 1 247 consumption (FAO, 2003).Canada 55 897 Other feedcrops are also important consum-UK* 70 887 ers of chemical N fertilizer. Grains like barleyBrazil 40 678 and sorghum receive large amounts of nitrogenSpain 42 491 fertilizer. Despite the fact that some oil crops areMexico 20 263 associated with N fixing organisms themselvesTurkey 17 262 (see Section 3.3.1), their intensive productionArgentina 29 126 often makes use of nitrogen fertilizer. Such crops* Countries with a considerable amount of N fertilized predominantly used as animal feed, including grassland. rapeseed, soybean and sunflower, garner con-Source: Based on FAO (2002; 2003). siderable amounts of N-fertilizer: 20 percent of Argentina’s total N fertilizer consumption is Except for the Western European countries, applied to production of such crops, 110 000production and consumption of chemical fertil- tonnes of N-fertilizer (for soybean alone) in Bra-izer is increasing in these countries. This high zil and over 1.3 million tonnes in China. In addi-proportion of N fertilizer going to animal feed is tion, in a number of countries even grasslandslargely owing to maize, which covers large areas receive a considerable amount of N fertilizer.in temperate and tropical climates and demands The countries of Table 3.3 together representhigh doses of nitrogen fertilizer. More than half the vast majority of the world’s nitrogen fertil-of total maize production is used as feed. Very izer use for feed production, adding a total oflarge amounts of N fertilizer are used for maize about 14 million tonnes of nitrogen fertilizer perand other animal feed, especially in nitrogen year into the animal food chain. When the Com-deficit areas such as North America, Southeast monwealth of Independent States and OceaniaAsia and Western Europe. In fact maize is the are added, the total rounds to around 20 percent of the annual 80 million tonnes of N fertilizer consumed worldwide. Adding in the fertilizer use4 The estimates are based on the assumption of a uniform that can be attributed to by-products other than share of fertilized area in both food and feed production. This oilcakes, in particular brans, may well take the may lead to a conservative estimate, considering the large- total up to some 25 percent. scale, intensive production of feedcrops in these countries On the basis of these figures, the correspond- compared to the significant contribution of small-scale, low input production to food supply. In addition, it should be noted ing emission of carbon dioxide can be esti- that these estimates do not consider the significant use of mated. Energy requirement in modern natural by-products other than oil cakes (brans, starch rich products, gas-based systems varies between 33 and 44 molasses, etc.). These products add to the economic value of the primary commodity, which is why some of the fertilizer gigajoules (GJ) per tonne of ammonia. Tak- applied to the original crop should be attributed to them. ing into consideration additional energy use in 87
    • Livestock’s long shadowTable 3.4Co2 emissions from the burning of fossil fuel to produce nitrogen fertilizer for feedcrops in selected countriesCountry Absolute amount Energy use Emission factor Emitted CO2 of chemical N fertilizer per tonnes fertilizer (1 000 tonnes N fertilizer) (GJ/tonnes N fertilizer) (tonnes C/TJ) (1 000 tonnes/year)Argentina 126 40 17 314Brazil 678 40 17 1 690Mexico 263 40 17 656Turkey 262 40 17 653China 2 998 50 26 14 290Spain 491 40 17 1 224UK* 887 40 17 2 212France* 1 317 40 17 3 284Germany* 1 247 40 17 3 109Canada 897 40 17 2 237USA 4 697 40 17 11 711Total 14 million tonnes 41 million tonnes* Includes a considerable amount of N fertilized grassland.Source: FAO (2002; 2003); IPCC (1997).packaging, transport and application of fertil- ruminants or concentrate feed for poultry orizer (estimated to represent an additional cost pigs. As well as the energy used for fertilizer,of at least 10 percent; Helsel, 1992), an upper important amounts of energy are also spent onlimit of 40 GJ per tonne has been applied here. seed, herbicides/pesticides, diesel for machin-As mentioned before, energy use in the case ery (for land preparation, harvesting, transport)of China is considered to be some 25 percent and electricity (irrigation pumps, drying, heat-higher, i.e. 50 GJ per tonne of ammonia. Taking ing, etc.). On-farm use of fossil fuel by intensivethe IPCC emission factors for coal in China (26 systems produces CO2 emissions probably eventonnes of carbon per terajoule) and for natural larger than those from chemical N fertilizer forgas elsewhere (17 tonnes C/TJ), estimating car- feed. Sainz (2003) estimated that, during thebon 100 percent oxidized (officially estimated to 1980s, a typical farm in the United States spentvary between 98 and 99 percent) and applying the some 35 megajoules (MJ) of energy per kilogramCO2/C molecular weight ratio, this results in an of carcass for chicken, 46 MJ for pigs and 51 MJestimated annual emission of CO2 of more than for beef, of which amounts 80 to 87 percent was40 million tonnes (Table 3.4) at this initial stage spent for production.5 A large share of this is inof the animal food chain. the form of electricity, producing much lower emissions on an energy equivalent basis than theOn-farm fossil fuel use may emit 90 million tonnes direct use of fossil sources for energy. The shareCO2 per year of electricity is larger for intensive monogastricsThe share of energy consumption accounted production (mainly for heating, cooling and ven-for by the different stages of livestock produc-tion varies widely, depending on the intensityof livestock production (Sainz, 2003). In modern 5 As opposed to post-harvest processing, transportation, stor-production systems the bulk of the energy is age and preparation. Production includes energy use for feedspent on production of feed, whether forage for production and transport.88
    • Livestock’s role in climate change and air pollutionTable 3.5On-farm energy use for agriculture in Minnesota, United StatesCommodity Minnesota Crop area Diesel LPG Electricity Directly ranking (103 km2) (1 000 m3 ~ (1 000 m3 ~ (106 kWh ~ emitted within USA head (106) 2.65–103 2.30–103 288 CO2 tonnes (106) tonnes CO2) tonnes CO2) tonnes CO2) (103 tonnes)Corn 4 27.1 238 242 235 1 255Soybeans 3 23.5 166 16 160 523Wheat 3 9.1 62 6.8 67 199Dairy (tonnes) 5 4.3 * 47 38 367 318Swine 3 4.85 59 23 230 275Beef 12 0.95 17 6 46 72Turkeys (tonnes) 2 40 14 76 50 226Sugar beets 1 1.7 46 6 45 149Sweet corn/peas 1 0.9 9 – 5 25Note: Reported nine commodities dominate Minnesota’s agricultural output and, by extension, the state’s agricultural energy use.Related CO2 emissions based on efficiency and emission factors from the United States’ Common Reporting Format report submittedto the UNFCCC in 2005.Source: Ryan and Tiffany (1998).tilation), which though also uses larger amounts maize fertilizer application (150 kg N per hectareof fossil fuel in feed transportation. However, for maize in the United States) results in emis-more than half the energy expenditure during sions for Minnesota maize of about one mil-livestock production is for feed production (near- lion tonnes of CO2, compared with 1.26 millionly all in the case of intensive beef operations). tonnes of CO2 from on-farm energy use for cornWe have already considered the contribution of production (see Table 3.5). At least half the CO2fertilizer production to the energy input for feed: emissions of the two dominant commodities andin intensive systems, the combined energy-use CO2 sources in Minnesota (maize and soybean)for seed and herbicide/pesticide production and can be attributed to the (intensive) livestock sec-fossil fuel for machinery generally exceeds that tor. Taken together, feed production and pig andfor fertilizer production. dairy operations make the livestock sector by far There are some cases where feed produc- the largest source of agricultural CO2 emissionstion does not account for the biggest share of in Minnesota.fossil energy use. Dairy farms are an important In the absence of similar estimates represen-example, as illustrated by the case of Minnesota tative of other world regions it remains impos-dairy operators. Electricity is their main form of sible to provide a reliable quantification of theenergy use. In contrast, for major staple crop global CO2 emissions that can be attributed tofarmers in the state, diesel is the dominant on farm fossil fuel-use by the livestock sector.form of on-farm energy use, resulting in much The energy intensity of production as well as thehigher CO2 emissions (Ryan and Tiffany, 1998, source of this energy vary widely. A rough indica-presenting data for 1995). On this basis, we can tion of the fossil fuel use related emissions fromsuggest that the bulk of Minnesota’s on-farm intensive systems can, nevertheless, be obtainedCO2 emissions from energy use are also related by supposing that the expected lower energyto feed production, and exceed the emissions need for feed production at lower latitudes (lowerassociated with N fertilizer use. The average energy need for corn drying for example) and the 89
    • Livestock’s long shadowelsewhere, often lower level of mechanization,are overall compensated by a lower energy useefficiency and a lower share of relatively low CO2emitting sources (natural gas and electricity).Minnesota figures can then be combined withglobal feed production and livestock populations © FAO/10460/F. Bottsin intensive systems. The resulting estimate formaize only is of a magnitude similar to the emis-sions from manufacturing N fertilizer for use onfeedcrops. As a conservative estimate, we maysuggest that CO2 emissions induced by on-farm Example of deforestation and shifting cultivationfossil fuel use for feed production may be 50 on steep hillside. Destruction of forests causes disastrous soil erosion in a few years – Thailand 1979percent higher than that from feed-dedicated Nfertilizer production, i.e. some 60 million tonnesCO2 globally. To this we must add farm emissionsrelated directly to livestock rearing, which we Livestock-related land use changes may emit 2.4may estimate at roughly 30 million tonnes of CO2 billion tonnes of CO2 per year(this figure is derived by applying Minnesota’s Land use in the various parts of the world isfigures to the global total of intensively-man- continually changing, usually in response toaged livestock populations, assuming that lower competitive demand between users. Changes inenergy use for heating at lower latitudes is land use have an impact in carbon fluxes, andcounterbalanced by lower energy efficiency and many of the land-use changes involve livestock,higher ventilation requirements). either occupying land (as pasture or arable land On-farm fossil fuel use induced emissions in for feedcrops) or releasing land for other pur-extensive systems sourcing their feed mainly poses, when for example, marginal pasture landfrom natural grasslands or crop residues can be is converted to forest.expected to be low or even negligible in compari- A forest contains more carbon than does ason to the above estimate. This is confirmed by field of annual crops or pasture, and so whenthe fact that there are large areas in developing forests are harvested, or worse, burned, largecountries, particularly in Africa and Asia, where amounts of carbon are released from the veg-animals are an important source of draught etation and soil to the atmosphere. The netpower, which could be considered as a CO2 emis- reduction in carbon stocks is not simply equalsion avoiding practice. It has been estimated to the net CO2 flux from the cleared area. Realitythat animal traction covered about half the total is more complex: forest clearing can produce aarea cultivated in the developing countries in complex pattern of net fluxes that change direc-1992 (Delgado et al., 1999). There are no more tion over time (IPCC guidelines). The calculationrecent estimates and it can be assumed that this of carbon fluxes owing to forest conversion is, inshare is decreasing quickly in areas with rapid many ways, the most complex of the emissionsmechanization, such as China or parts of India. inventory components. Estimates of emissionsHowever, draught animal power remains an from forest clearing vary because of multipleimportant form of energy, substituting for fossil uncertainties: annual forest clearing rates, thefuel combustion in many parts of the world, and fate of the cleared land, the amounts of carbonin some areas, notably in West Africa, is on the contained in different ecosystems, the modes byincrease. which CO2 is released (e.g., burning or decay),90
    • Livestock’s role in climate change and air pollutionand the amounts of carbon released from soils into forest by an annual average of 2.4 millionwhen they are disturbed. hectares – equivalent to some 65 percent of Responses of biological systems vary over dif- expected deforestation. If we also assume thatferent time-scales. For example, biomass burn- at least half the cropland expansion into foresting occurs within less than one year, while the in Bolivia and Brazil can be attributed to provid-decomposition of wood may take a decade, and ing feed for the livestock sector, this results inloss of soil carbon may continue for several an additional annual deforestation for livestockdecades or even centuries. The IPCC (2001b) of over 0.5 million hectares – giving a total forestimated the average annual flux owing to trop- pastures plus feedcrop land, of some 3 millionical deforestation for the decade 1980 to 1989 hectares per year.at 1.6±1.0 billion tonnes C as CO2 (CO2-C). Only In view of this, and of worldwide trends inabout 50–60 percent of the carbon released from extensive livestock production and in croplandforest conversion in any one year was a result of for feed production (Chapter 2), we can realisti-the conversion and subsequent biomass burning cally estimate that “livestock induced” emissionsin that year. The remainder were delayed emis- from deforestation amount to roughly 2.4 billionsions resulting from oxidation of biomass har- tonnes of CO2 per year. This is based on thevested in previous years (Houghton, 1991). somewhat simplified assumption that forests are Clearly, estimating CO2 emissions from land completely converted into climatically equiva-use and land-use change is far less straightfor- lent grasslands and croplands (IPCC 2001b, p.ward than those related to fossil fuel combus- 192), combining changes in carbon density oftion. It is even more difficult to attribute these both vegetation and soil6 in the year of change.emissions to a particular production sector such Though physically incorrect (it takes well overas livestock. However, livestock’s role in defores- a year to reach this new status because of thetation is of proven importance in Latin America, “inherited”, i.e. delayed emissions) the result-the continent suffering the largest net loss of ing emission estimate is correct provided theforests and resulting carbon fluxes. In Chapter change process is continuous.2 Latin America was identified as the region Other possibly important, but un-quantified,where expansion of pasture and arable land for livestock-related deforestation as reported fromfeedcrops is strongest, mostly at the expense of for example Argentina (see Box 5.5 in Sectionforest area. The LEAD study by Wassenaar et al., 5.3.3) is excluded from this estimate.(2006) and Chapter 2 showed that most of the In addition to producing CO2 emissions, thecleared area ends up as pasture and identified land conversion may also negatively affect otherlarge areas where livestock ranching is probably emissions. Mosier et al. (2004) for examplea primary motive for clearing. Even if these final noted that upon conversion of forest to grazingland uses were only one reason among many land, CH4 oxidation by soil micro-organisms isothers that led to the forest clearing, animal pro- typically greatly reduced and grazing lands mayduction is certainly one of the driving forces of even become net sources in situations wheredeforestation. The conversion of forest into pas- soil compaction from cattle traffic limits gasture releases considerable amounts of carbon diffusion.into the atmosphere, particularly when the areais not logged but simply burned. Cleared patches 6 The most recent estimates provided by this source are 194may go through several changes of land-use and 122 tonnes of carbon per hectare in tropical forest,type. Over the 2000–2010 period, the pasture respectively for plants and soil, as opposed to 29 and 90 forareas in Latin America are projected to expand tropical grassland and 3 and 122 for cropland. 91
    • Livestock’s long shadowLivestock-related releases from cultivated soils dominated by conventional tillage practices thatmay total 28 million tonnes CO2 per year gradually lower the soil organic carbon contentSoils are the largest carbon reservoir of the and produce significant CO2 emissions. Given theterrestrial carbon cycle. The estimated total complexity of emissions from land use and land-amount of carbon stored in soils is about 1 100 to use changes, it is not possible to make a global1 600 billion tonnes (Sundquist, 1993), more than estimation at an acceptable level of precision.twice the carbon in living vegetation (560 billion Order-of-magnitude indications can be made bytonnes) or in the atmosphere (750 billion tonnes). using an average loss rate from soil in a ratherHence even relatively small changes in carbon temperate climate with moderate to low organicstored in the soil could make a significant impact matter content that is somewhere between theon the global carbon balance (Rice, 1999). loss rate reported for zero and conventional till- Carbon stored in soils is the balance between age: Assuming an annual loss rate of 100 kg CO2the input of dead plant material and losses due per hectare per year (Sauvé et al., 2000: coveringto decomposition and mineralization processes. temperate brown soil CO2 loss, and excludingUnder aerobic conditions, most of the carbon emissions originating from crop residues), theentering the soil is unstable and therefore quick- approximately 1.8 million km2 of arable land cul-ly respired back to the atmosphere. Generally, tivated with maize, wheat and soybean for feedless than 1 percent of the 55 billion tonnes of would add an annual CO2 flux of some 18 millionC entering the soil each year accumulates in tonnes to the livestock balance.more stable fractions with long mean residence Tropical soils have lower average carbon con-times. tent (IPCC 2001b, p. 192), and therefore lower Human disturbance can speed up decomposi- emissions. On the other hand, the considerabletion and mineralization. On the North American expansion of large-scale feedcropping, not onlyGreat Plains, it has been estimated that approxi- into uncultivated areas, but also into previ-mately 50 percent of the soil organic carbon has ous pastureland or subsistence cropping, maybeen lost over the past 50 to 100 years of culti- increase CO2 emission. In addition, practicesvation, through burning, volatilization, erosion, such as soil liming contribute to emissions. Soilharvest or grazing (SCOPE 21, 1982). Similar liming is a common practice in more inten-losses have taken place in less than ten years sively cultivated tropical areas because of soilafter deforestation in tropical areas (Nye and acidity. Brazil7 for example estimated its CO2Greenland, 1964). Most of these losses occur emissions owing to soil liming at 8.99 millionat the original conversion of natural cover into tonnes in 1994, and these have most probablymanaged land. increased since than. To the extent that these Further soil carbon losses can be induced emissions concern cropland for feed productionby management practices. Under appropriate they should be attributed to the livestock sec-management practices (such as zero tillage) tor. Often only crop residues and by-productsagricultural soils can serve as a carbon sink and are used for feeding, in which case a share ofmay increasingly do so in future (see Section emissions corresponding to the value fraction of3.5.1). Currently, however, their role as carbon the commodity8 (Chapagain and Hoekstra, 2004)sinks is globally insignificant. As described in should be attributed to livestock. ComparingChapter 2, a very large share of the production ofcoarse grains and oil crops in temperate regions 7 Brazil’s first national communication to the UNFCCC, 2004.is destined for feed use. 8 The value fraction of a product is the ratio of the market The vast majority of the corresponding area value of the product to the aggregated market value of all theis under large-scale intensive management, products obtained from the primary crop.92
    • Livestock’s role in climate change and air pollutionreported emissions from liming from national stocks and cycling of the system. This seemscommunications of various tropical countries to to result in a small reduction in aboveground Cthe UNFCCC with the importance of feed pro- stocks and a slight decline in C fixation. Despiteduction in those countries shows that the global the small, sometimes undetectable changes inshare of liming related emissions attributable to aboveground biomass, total soil carbon usu-livestock is in the order of magnitude of Brazil’s ally declines. A recent study by Asner, Borghiemission (0.01 billion tonnes CO2). and Ojeda, (2003) in Argentina also found that Another way livestock contributes to gas emis- desertification resulted in little change in woodysions from cropland is through methane emis- cover, but there was a 25 to 80 percent declinesions from rice cultivation, globally recognized in soil organic carbon in areas with long-termas an important source of methane. Much of the grazing. Soil erosion accounts for part of thismethane emissions from rice fields are of animal loss, but the majority stems from the non-origin, because the soil bacteria are to a large renewal of decaying organic matter stocks, i.e.extent “fed” with animal manure, an important there is a significant net emission of CO2.fertilizer source (Verburg, Hugo and van der Lal (2001) estimated the carbon loss as aGon, 2001). Together with the type of flooding result of desertification. Assuming a loss of 8‑12management, the type of fertilization is the most tonnes of soil carbon per hectare (Swift et al.,important factor controlling methane emissions 1994) on a desertified land area of 1 billion hect-from rice cultivated areas. Organic fertilizers ares (UNEP, 1991), the total historic loss wouldlead to higher emissions than mineral fertilizers. amount to 8–12 billion tonnes of soil carbon.Khalil and Shearer (2005) argue that over the last Similarly, degradation of aboveground vegeta-two decades China achieved a substantial reduc- tion has led to an estimated carbon loss of 10–16tion of annual methane emissions from rice tonnes per hectare – a historic total of 10–16cultivation – from some 30 million tonnes per billion tonnes. Thus, the total C loss as a con-year to perhaps less than 10 million tonnes per sequence of desertification may be 18–28 billionyear – mainly by replacing organic fertilizer with tonnes of carbon (FAO, 2004b). Livestock’s con-nitrogen-based fertilizers. However, this change tribution to this total is difficult to estimate, butcan affect other gaseous emissions in the oppo- it is undoubtedly high: livestock occupies aboutsite way. As nitrous oxide emissions from rice two-thirds of the global dry land area, and thefields increase, when artificial N fertilizers are rate of desertification has been estimated to beused, as do carbon dioxide emissions from Chi- higher under pasture than under other land usesna’s flourishing charcoal-based nitrogen fertil- (3.2 million hectares per year against 2.5 millionizer industry (see preceding section). Given that hectares per year for cropland, UNEP, 1991).it is impossible to provide even a rough estimate Considering only soil carbon loss (i.e. about 10of livestock’s contribution to methane emissions tonnes of carbon per hectare), pasture desertifi-from rice cultivation, this is not further consid- cation-induced oxidation of carbon would resultered in the global quantification. in CO2 emissions in the order of 100 million tonnes of CO2 per year.Releases from livestock-induced desertification of Another, largely unknown, influence on the fatepastures may total 100 million tonnes CO2 per year of soil carbon is the feedback effect of climateLivestock also play a role in desertification (see change. In higher latitude cropland zones, globalChapters 2 and 4). Where desertification is warming is expected to increase yields by virtueoccurring, degradation often results in reduced of longer growing seasons and CO2 fertilizationproductivity or reduced vegetation cover, which (Cantagallo, Chimenti and Hall, 1997; Travassoproduce a change in the carbon and nutrient et al., 1999). At the same time, however, global 93
    • Livestock’s long shadow Box 3.2 The many climatic faces of the burning of tropical savannah Burning is common in establishing and managing burning represented some 85 percent of the area of pastures, tropical rain forests and savannah burned in Latin American fires 2000, 60 percent in regions and grasslands worldwide (Crutzen and Africa, nearly 80 percent in Australia. Andreae, 1990; Reich et al., 2001). Fire removes Usually, savannah burning is not considered to ungrazed grass, straw and litter, stimulates fresh result in net CO2 emissions, since emitted amounts growth, and can control the density of woody plants of carbon dioxide released in burning are re-cap- (trees and shrubs). As many grass species are more tured in grass re-growth. As well as CO2, biomass fire-tolerant than tree species (especially seedlings burning releases important amounts of other glob- and saplings), burning can determine the balance ally relevant trace gases (NOx, CO, and CH4) and between grass cover and ligneous vegetation. Fires aerosols (Crutzen and Andreae, 1990; Scholes and stimulate the growth of perennial grasses in savan- Andreae, 2000). Climate effects include the forma- nahs and provide nutritious re-growth for livestock. tion of photochemical smog, hydrocarbons, and Controlled burning prevents uncontrolled, and pos- NOx. Many of the emitted elements lead to the pro- sibly, more destructive fires and consumes the duction of tropospheric ozone (Vet, 1995; Crutzen combustible lower layer at an appropriate humidity and Goldammer, 1993), which is another important stage. Burning involves little or no cost. It is also greenhouse gas influencing the atmosphere’s oxi- used at a small scale to maintain biodiversity (wild- dizing capacity, while bromine, released in sig- life habitats) in protected areas. nificant amounts from savannah fires, decreases The environmental consequences of rangeland stratospheric ozone (Vet, 1995; ADB, 2001). and grassland fires depend on the environmental Smoke plumes may be redistributed locally, context and conditions of application. Controlled transported throughout the lower troposphere, burning in tropical savannah areas has signifi- or entrained in large-scale circulation patterns cant environmental impact, because of the large in the mid and upper troposphere. Often fires in area concerned and the relatively low level of convection areas take the elements high into the control. Large areas of savannah in the humid atmosphere, creating increased potential for cli- and subhumid tropics are burned every year for mate change. Satellite observations have found rangeland management. In 2000, burning affected large areas with high O3 and CO levels over Africa, some 4 million km2. More than two-thirds of this South America and the tropical Atlantic and Indian occurred in the tropics and sub-tropics (Tansey Oceans (Thompson et al., 2001). et al., 2004). Globally about three quarters of Aerosols produced by the burning of pasture this burning took place outside forests. Savannah biomass dominate the atmospheric concentra- tion of aerosols over the Amazon basin and Africa (Scholes and Andreae, 2000; Artaxo et al., 2002). Concentrations of aerosol particles are highly sea- sonal. An obvious peak in the dry (burning) season, © FAO/14185/R. Faidutti which contributes to cooling both through increas- ing atmospheric scattering of incoming light and the supply of cloud condensation nuclei. High con- centrations of cloud condensation nuclei from the burning of biomass stimulate rainfall production Hunter set fire to forest areas to drive out a species of rodent that will be killed for food. Herdsmen and and affect large-scale climate dynamics (Andreae hunters together benefit from the results. and Crutzen, 1997).94
    • Livestock’s role in climate change and air pollutionwarming may also accelerate decomposition of ries, ruminants have higher emissions relative tocarbon already stored in soils (Jenkinson,1991; their output. Cattle alone account for more thanMacDonald, Randlett and Zalc, 1999; Niklinska, half of the total carbon dioxide emissions fromMaryanski and Laskowski, 1999; Scholes et al., respiration.1999). Although much work remains to be done However, emissions from livestock respirationin quantifying the CO2 fertilization effect in crop- are part of a rapidly cycling biological system,land, van Ginkel, Whitmore and Gorissen, (1999) where the plant matter consumed was itselfestimate the magnitude of this effect (at current created through the conversion of atmosphericrates of increase of CO2 in the atmosphere) at CO2 into organic compounds. Since the emit-a net absorption of 0.036 tonnes of carbon per ted and absorbed quantities are consideredhectare per year in temperate grassland, even to be equivalent, livestock respiration is notafter the effect of rising temperature on decom- considered to be a net source under the Kyotoposition is deducted. Recent research indicates Protocol. Indeed, since part of the carbon con-that the magnitude of the temperature rise on sumed is stored in the live tissue of the growingthe acceleration of decay may be stronger, with animal, a growing global herd could even bealready very significant net losses over the last considered a carbon sink. The standing stockdecades in temperate regions (Bellamy et al., livestock biomass increased significantly over2005; Schulze and Freibauer, 2005). Both sce- the last decades (from about 428 million tonnesnarios may prove true, resulting in a shift of car- in 1961 to around 699 million tonnes in 2002).bon from soils to vegetation – i.e. a shift towards This continuing growth (see Chapter 1) could bemore fragile ecosystems, as found currently in considered as a carbon sequestration processmore tropical regions. (roughly estimated at 1 or 2 million tonnes car- bon per year). However, this is more than offset3.2.2 Carbon emissions from livestock by methane emissions which have increasedrearing correspondingly.Respiration by livestock is not a net source of CO2 The equilibrium of the biological cycle is, how-Humans and livestock now account for about a ever, disrupted in the case of overgrazing or badquarter of the total terrestrial animal biomass.9 management of feedcrops. The resulting landBased on animal numbers and liveweights, the degradation is a sign of decreasing re-absorp-total livestock biomass amounts to some 0.7 bil- tion of atmospheric CO2 by vegetation re-growth.lion tonnes (Table 3.6; FAO, 2005b). In certain regions the related net CO2 loss may How much do these animals contribute to be significant.greenhouse gas emissions? According to thefunction established by Muller and Schneider Methane released from enteric fermentation may(1985, cited by Ni et al., 1999), applied to stand- total 86 million tonnes per yearing stocks per country and species (with country Globally, livestock are the most important sourcespecific liveweight), the carbon dioxide from the of anthropogenic methane emissions. Amongrespiratory process of livestock amount to some domesticated livestock, ruminant animals (cat-3 billion tonnes of CO2 (see Table 3.6) or 0.8 bil- tle, buffaloes, sheep, goats and camels) producelion tonnes of carbon. In general, because of significant amounts of methane as part of theirlower offtake rates and therefore higher invento- normal digestive processes. In the rumen, or large fore-stomach, of these animals, microbial fermentation converts fibrous feed into products9 Based on SCOPE 13 (Bolin et al., 1979), with human popula- that can be digested and utilized by the animal. tion updated to today’s total of some 6.5 billion. This microbial fermentation process, referred to 95
    • Livestock’s long shadow Table 3.6 Livestock numbers (2002) and estimated carbon dioxide emissions from respiration Species World total Biomass Carbon dioxide emissions (million head) (million tonnes liveweight) (million tonnes CO2) Cattle and buffaloes 1 496 501 1 906 Small ruminants 1 784 47.3 514 Camels 19 5.3 18 Horses 55 18.6 71 Pigs 933 92.8 590 Poultry1 17 437 33.0 61 Total2 699 3 161 1 Chicken, ducks, turkey and geese. 2 Includes also rabbits. Source: FAO (2006b); own calculations. as enteric fermentation, produces methane as enteric fermentation totalled 5.5 million tonnes a by-product, which is exhaled by the animal. in 2002, again overwhelmingly originating from Methane is also produced in smaller quantities beef and dairy cattle. This was 71 percent of all by the digestive processes of other animals, agricultural emissions and 19 percent of the including humans (US-EPA, 2005). country’s total emissions (US-EPA, 2004). There are significant spatial variations in This variation reflects the fact that levels of methane emissions from enteric fermentation. methane emission are determined by the pro- In Brazil, methane emission from enteric fer- duction system and regional characteristics. mentation totalled 9.4 million tonnes in 1994 ‑ 93 They are affected by energy intake and several percent of agricultural emissions and 72 percent other animal and diet factors (quantity and qual- of the country’s total emissions of methane. Over ity of feed, animal body weight, age and amount 80 percent of this originated from beef cattle of exercise). It varies among animal species and (Ministério da Ciência e Tecnologia ‑ EMBRAPA among individuals of the same species. There- report, 2002). In the United States methane from fore, assessing methane emission from enteric fermentation in any particular country requires a detailed description of the livestock population (species, age and productivity categories), com- bined with information on the daily feed intake and the feed’s methane conversion rate (IPCC revised guidelines). As many countries do not possess such detailed information, an approach based on standard emission factors is generally used in emission reporting. Methane emissions from enteric fermentation© FAO/15228/A. Conti will change as production systems change and move towards higher feed use and increased productivity. We have attempted a global esti- mate of total methane emissions from enteric Dairy cattle feeding on fodder in open stable. La Loma, fermentation in the livestock sector. Annex 3.2 Lerdo, Durango – Mexico 1990 details the findings of our assessment, compar- 96
    • Livestock’s role in climate change and air pollutionTable 3.7Global methane emissions from enteric fermentation in 2004 Emissions (million tonnes CH4 per year by source)Region/country Dairy cattle Other cattle Buffaloes Sheep and goats Pigs TotalSub-Saharan Africa 2.30 7.47 0.00 1.82 0.02 11.61Asia * 0.84 3.83 2.40 0.88 0.07 8.02India 1.70 3.94 5.25 0.91 0.01 11.82China 0.49 5.12 1.25 1.51 0.48 8.85Central and South America 3.36 17.09 0.06 0.58 0.08 21.17West Asia and North Africa 0.98 1.16 0.24 1.20 0.00 3.58North America 1.02 3.85 0.00 0.06 0.11 5.05Western Europe 2.19 2.31 0.01 0.98 0.20 5.70Oceania and Japan 0.71 1.80 0.00 0.73 0.02 3.26Eastern Europe and CIS 1.99 2.96 0.02 0.59 0.10 5.66Other developed 0.11 0.62 0.00 0.18 0.00 0.91Total 15.69 50.16 9.23 9.44 1.11 85.63Livestock Production SystemGrazing 4.73 21.89 0.00 2.95 0.00 29.58Mixed 10.96 27.53 9.23 6.50 0.80 55.02Industrial 0.00 0.73 0.00 0.00 0.30 1.04* Excludes China and India.Source: see Annex 3.2, own calculations.ing IPCC Tier 1 default emission factors with Methane released from animal manure may totalregion-specific emission factors. Applying these 18 million tonnes per yearemission factors to the livestock numbers in The anaerobic decomposition of organic mate-each production system gives an estimate for rial in livestock manure also releases methane.total global emissions of methane from enteric This occurs mostly when manure is managed infermentation 86 million tonnes CH4 annually. liquid form, such as in lagoons or holding tanks.This is not far from the global estimate from the Lagoon systems are typical for most large-scaleUnited States Environmental Protection Agency pig operations over most of the world (except(US-EPA, 2005), of about 80 million tonnes of in Europe). These systems are also used inmethane annually. The regional distribution of large dairy operations in North America and insuch methane emission is illustrated by Map 33 some developing countries, for example Brazil.(Annex 1). This is an updated and more precise Manure deposited on fields and pastures, or oth-estimate than previous such attempts (Bowman erwise handled in a dry form, does not produceet al., 2000; Methane emission map published by significant amounts of methane.UNEP-GRID, Lerner, Matthews and Fung, 1988) Methane emissions from livestock manureand also provides production-system specific are influenced by a number of factors thatestimates. Table 3.7 summarizes these results. affect the growth of the bacteria responsible forThe relative global importance of mixed systems methane formation, including ambient tempera-compared to grazing systems reflects the fact ture, moisture and storage time. The amount ofthat about two-thirds of all ruminants are held methane produced also depends on the energyin mixed systems. content of manure, which is determined to a 97
    • Livestock’s long shadow© Photo courtesy of USDA NRCS/Jeff Vanuga State of the art lagoon waste management system for a 900 head hog farm. The facility is completely automated and temperature controlled – United States 2002 large extent by livestock diet. Not only do greater very far behind, the latter in particular exhibit- amounts of manure lead to more CH4 being ing a strong increase. The default emission emitted, but higher energy feed also produces factors currently used in country reporting to manure with more volatile solids, increasing the the UNFCCC do not reflect such strong changes substrate from which CH4 is produced. However, in the global livestock sector. For example, this impact is somewhat offset by the possibil- Brazil’s country report to the UNFCCC (Ministry ity of achieving higher digestibility in feeds, and of Science and Technology, 2004) mentions a thus less wasted energy (USDA, 2004). significant emission from manure of 0.38 million Globally, methane emissions from anaerobic tonnes in 1994, which would originate mainly decomposition of manure have been estimated from dairy and beef cattle. However, Brazil also to total just over 10 million tonnes, or some has a very strong industrial pig production sec- 4 percent of global anthropogenic methane tor, where some 95 percent of manure is held in emissions (US-EPA, 2005). Although of much open tanks for several months before application lesser magnitude than emissions from enteric (EMBRAPA, personal communication). fermentation, emissions from manure are much Hence, a new assessment of emission factors higher than those originating from burning resi- similar to the one presented in the preceding dues and similar to the lower estimate of the section was essential and is presented in Annex badly known emissions originating from rice cul- 3.3. Applying these new emission factors to the tivation. The United States has the highest emis- animal population figures specific to each pro- sion from manure (close to 1.9 million tonnes, duction system, we arrive at a total annual global United States inventory 2004), followed by the emission of methane from manure decomposi- EU. As a species, pig production contributes tion of 17.5 million tonnes of CH4. This is sub- the largest share, followed by dairy. Developing stantially higher than existing estimates. countries such as China and India would not be Table 3.8 summarizes the results by species, 98
    • Livestock’s role in climate change and air pollutionTable 3.8Global methane emissions from manure management in 2004 Emissions (million tonnes CH4 per year by source)Region/country Dairy cattle Other cattle Buffalo Sheep and goats Pigs Poultry TotalSub-Saharan Africa 0.10 0.32 0.00 0.08 0.03 0.04 0.57Asia * 0.31 0.08 0.09 0.03 0.50 0.13 1.14India 0.20 0.34 0.19 0.04 0.17 0.01 0.95China 0.08 0.11 0.05 0.05 3.43 0.14 3.84Central and South America 0.10 0.36 0.00 0.02 0.74 0.19 1.41West Asia and North Africa 0.06 0.09 0.01 0.05 0.00 0.11 0.32North America 0.52 1.05 0.00 0.00 1.65 0.16 3.39Western Europe 1.16 1.29 0.00 0.02 1.52 0.09 4.08Oceania and Japan 0.08 0.11 0.00 0.03 0.10 0.03 0.35Eastern Europe and CIS 0.46 0.65 0.00 0.01 0.19 0.06 1.38Other developed 0.01 0.03 0.00 0.01 0.04 0.02 0.11Global Total 3.08 4.41 0.34 0.34 8.38 0.97 17.52Livestock Production SystemGrazing 0.15 0.50 0.00 0.12 0.00 0.00 0.77Mixed 2.93 3.89 0.34 0.23 4.58 0.31 12.27Industrial 0.00 0.02 0.00 0.00 3.80 0.67 4.48* Excludes China and India.Source: see Annex 3.3, own calculations.by region and by farming system. The distribu- to 5.02 million joules per kilogram of live weight.tion by species and production system is also Sainz (2003) produced indicative values for theillustrated in Maps 16, 17, 18 and 19 (Annex 1). energy costs of processing, given in Table 3.9.China has the largest country-level methaneemission from manure in the world, mainly CO2 emissions from livestock processing may totalfrom pigs. At a global level, emissions from pig several tens of million tonnes per yearmanure represent almost half of total livestock To obtain a global estimate of emissions frommanure emissions. Just over a quarter of the processing, these indicative energy use fac-total methane emission from managed manure tors could be combined with estimates of theoriginates from industrial systems. world’s livestock production from market-ori- ented intensive systems (Chapter 2). However,3.2.3 Carbon emissions from livestock besides their questionable global validity, it isprocessing and refrigerated transport highly uncertain what the source of this energyA number of studies have been conducted to is and how this varies throughout the world.quantify the energy costs of processing animals Since mostly products from intensive systemsfor meat and other products, and to identify are being processed, the above case of Min-potential areas for energy savings (Sainz, 2003). nesota (Section 3.2.1 on on-farm fossil fuel useThe variability among enterprises is very wide, and Table 3.5) constitutes an interesting exampleso it is difficult to generalize. For example, Ward, of energy use for processing, as well as a break-Knox and Hobson, (1977) reported energy costs down into energy sources (Table 3.13). Dieselof beef processing in Colorado ranging from 0.84 use here is mainly for transport of products 99
    • Livestock’s long shadowTable 3.9Indicative energy costs for processingProduct Fossil energy cost Units SourcePoultry meat 2.590 MJ-kg-1 live wt Whitehead and Shupe, 1979Eggs 6.120 MJ-dozen-1 OECD, 1982Pork-fresh 3.760 MJ-kg-1 carcass Singh, 1986Pork-processed meats 6.300 MJ-kg-1 meat Singh, 1986Sheep meat 10.4000 MJ-kg-1 carcass McChesney et al., 1982Sheep meat-frozen 0.432 MJ-kg-1 meat Unklesbay and Unklesbay, 1982Beef 4.370 MJ-kg-1 carcass Poulsen, 1986Beef-frozen 0.432 MJ-kg-1 meat Unklesbay and Unklesbay, 1982Milk 1.120 MJ-kg-1 Miller, 1986Cheese, butter, whey powder 1.490 MJ-kg-1 Miller, 1986Milk powder, butter 2.620 MJ-kg-1 Miller, 1986Source: Sainz (2003).to the processing facilities. Transport-related few million tonnes CO2. Therefore, the probableemissions for milk are high, owing to large vol- order of magnitude for the emission level relatedumes and low utilization of transport capacity. to global animal-product processing would beIn addition, large amounts of energy are used to several tens of million tonnes CO2.pasteurize milk and transform it into cheese anddried milk, making the dairy sector responsible CO2 emissions from transport of livestock productsfor the second highest CO2 emissions from food may exceed 0.8 million tonnes per yearprocessing in Minnesota. The largest emissions The last element of the food chain to be con-result from soybean processing and are a result sidered in this review of the carbon cycle is theof physical and chemical methods to separate one that links the elements of the productionthe crude soy oil and soybean meal from the raw chain and delivers the product to retailers andbeans. Considering the value fractions of these consumers, i.e. transport. In many instancestwo commodities (see Chapagain and Hoekstra, transport is over short distances, as in the case2004) some two-thirds of these soy-processing of milk collection cited above. Increasingly theemissions can be attributed to the livestock sec- steps in the chain are separated over long dis-tor. Thus, the majority of CO2 emissions related tances (see Chapter 2), which makes transportto energy consumption from processing Minne- a significant source of greenhouse gas emis-sota’s agricultural production can be ascribed to sions.the livestock sector. Transport occurs mainly at two key stages: Minnesota can be considered a “hotspot” delivery of (processed) feed to animal produc-because of its CO2 emissions from livestock tion sites and delivery of animal products toprocessing and cannot, in light of the above consumer markets. Large amounts of bulky rawremarks on the variability of energy efficiency ingredients for concentrate feed are shippedand sources, be used as a basis for deriv- around the world (Chapter 2). These long-dis-ing a global estimate. Still, considering also tance flows add significant CO2 emissions to theTable 3.10, it indicates that the total animal livestock balance. One of the most notable long-product and feed processing related emission distance feed trade flows is for soybean, whichof the United States would be in the order of a is also the largest traded volume among feed100
    • Livestock’s role in climate change and air pollutionTable 3.10Energy use for processing agricultural products in Minnesota, in United States in 1995Commodity Production1 Diesel Natural gas Electricity Emitted CO2 (106 tonnes) (1000 m3) (106 m3) (106 kWh) (103 tonnes)Corn 22.2 41 54 48 226Soybeans 6.4 23 278 196 648Wheat 2.7 19 – 125 86Dairy 4.3 36 207 162 537Swine 0.9 7 21 75 80Beef 0.7 2.5 15 55 51Turkeys 0.4 1.8 10 36 34Sugar beets2 7.4 19 125 68 309Sweet corn/peas 1.0 6 8 29 401 Commodities: unshelled corn ears, milk, live animal weight. 51 percent of milk is made into cheese, 35 percent is dried, and 14 percent is used as liquid for bottling.2 Beet processing required an additional 440 thousand tonnes of coal.1 000 m3 diesel ~ 2.65•103 tonnes CO2; 106 m3 natural gas ~ 1.91•103 tonnes CO2; 106 kWh ~ 288 tonnes CO2Source: Ryan and Tiffany (1998). See also table 3.5. Related CO2 emissions based on efficiency and emission factors from the UnitedStates’ Common Reporting Format report submitted to the UNFCCC in 2005.ingredients, as well as the one with the strongest international meat trade. Annually they pro-increase. Among soybean (cake) trade flows the duce some 500 thousand tonnes of CO2. Thisone from Brazil to Europe is of a particularly represents more than 60 percent of total CO2important volume. Cederberg and Flysjö (2004) emissions induced by meat-related sea trans-studied the energy cost of shipping soybean cake port, because the trade flow selection is biasedfrom the Mato Grosso to Swedish dairy farms: towards the long distance exchange. On theshipping one tonne requires some 2 900 MJ, of other hand, surface transport to and from thewhich 70 percent results from ocean transport. harbour has not been considered. Assuming, forApplying this energy need to the annual soybean simplicity, that the latter two effects compensatecake shipped from Brazil to Europe, combined each other, the total annual meat transport-with the IPCC emission factor for ocean vessel induced CO2 emission would be in the order ofengines, results in an annual emission of some 800‑850 thousand tonnes of CO2.32 thousand tonnes of CO2. While there are a large number of trade flows, 3.3 Livestock in the nitrogen cyclewe can take pig, poultry and bovine meat to rep- Nitrogen is an essential element for life andresent the emissions induced by fossil energy plays a central role in the organization and func-use for shipping animal products around the tioning of the world’s ecosystems. In many ter-world. The figures presented in Table 15, Annex restrial and aquatic ecosystems, the availability2 are the result of combining traded volumes of nitrogen is a key factor determining the nature(FAO, accessed December 2005) with respective and diversity of plant life, the population dynam-distances, vessel capacities and speeds, fuel use ics of both grazing animals and their predators,of main engine and auxiliary power generators and vital ecological processes such as plantfor refrigeration, and their respective emission productivity and the cycling of carbon and soilfactors (IPCC, 1997). minerals (Vitousek et al., 1997). These flows represent some 60 percent of The natural carbon cycle is characterized by 101
    • Livestock’s long shadow Figure 3.2 The nitrogen cycle Atmosphere 4 000 000 000 Fixation in Denitrification 130 140 Biological 100 Industrial Denitrification 110 lightning fixation fixation Human activities 20 Terrestrial vegetation 3 500 Internal Soil erosion, runoff Biological cycling and river flow fixation 30 1 200 36 Oceans Soils organic matter 6 000 9 500 Source: Porter and Botkin (1999).large fossil terrestrial and aquatic pools, and For most organisms this nutrient is supplied viaan atmospheric form that is easily assimilated the tissues of living and dead organisms, whichby plants. The nitrogen cycle is quite different: is why many ecosystems of the world are limiteddiatomic nitrogen (N2) in the atmosphere is the by nitrogen.sole stable (and very large) pool, making up The few organisms able to assimilate atmos-some 78 percent of the atmosphere (see Figure pheric N2 are the basis of the natural N cycle of3.2). modest intensity (relative to that of the C cycle), Although nitrogen is required by all organ- resulting in the creation of dynamic pools inisms to survive and grow, this pool is largely organic matter and aquatic resources. Generallyunavailable to them under natural conditions. put, nitrogen is removed from the atmosphere102
    • Livestock’s role in climate change and air pollutionby soil micro-organisms, such as the nitrogen- that human intervention in the nitrogen cyclefixing bacteria that colonize the roots of legumi- has changed the balance of N species in thenous plants. These bacteria convert it into forms atmosphere and other reservoirs. Non-reactive(so-called reactive nitrogen, Nr, in essence all molecular nitrogen is neither a greenhouse gasN compounds other than N2) such as ammonia nor an air polluter. However, human activities(NH3), which can then be used by the plants. This return much of it in the form of reactive nitrogenprocess is called nitrogen fixation. Meanwhile, species which either is a greenhouse gas or another micro-organisms remove nitrogen from air polluter. Nitrous oxide is very persistent inthe soil and put it back into the atmosphere. the atmosphere where it may last for up to 150This process, called denitrification, returns N to years. In addition to its role in global warm-the atmosphere in various forms, primarily N2. ing, N2O is also involved in the depletion of theIn addition, denitrification produces the green- ozone layer, which protects the biosphere fromhouse gas nitrous oxide. the harmful effects of solar ultraviolet radiation (Bolin et al., 1981). Doubling the concentration ofThe human impact on the nitrogen cycle N2O in the atmosphere would result in an esti-The modest capability of natural ecosystems mated 10 percent decrease in the ozone layer,to drive the N cycle constituted a major hurdle which in turn would increase the ultravioletin satisfying the food needs of growing popu- radiation reaching the earth by 20 percent.lations (Galloway et al., 2004). The historical The atmospheric concentration of nitrousincreases of legume, rice and soybean cultiva- oxide has steadily increased since the begin-tion increased N fixation, but the needs of large ning of the industrial era and is now 16 percentpopulations could only be met after the invention (46 ppb) larger than in 1750 (IPCC, 2001b).of the Haber-Bosch process in the first decade of Natural sources of N2O are estimated to emitthe twentieth century, to transform N2 into min- approximately 10 million tonnes N/yr, with soilseral fertilizers (see section on feed sourcing). contributing about 65 percent and oceans about In view of the modest natural cycling intensity, 30 percent. According to recent estimates, N2Oadditions of chemical N fertilizers had dramatic emissions from anthropogenic sources (agri-effects. It has been estimated that humans have culture, biomass burning, industrial activitiesalready doubled the natural rate of nitrogen and livestock management) amount to approxi-entering the land-based nitrogen cycle and this mately 7–8 million tonnes N/yr (van Aardennerate is continuing to grow (Vitousek et al., 1997). et al., 2001; Mosier et al., 2004). According toSynthetic fertilizers now provide about 40 per- these estimates, 70 percent of this results fromcent of all the nitrogen taken up by crops (Smil, agriculture, both crop and livestock production.2001). Unfortunately crop, and especially animal, Anthropogenic NO emissions also increasedproduction uses this additional resource at a substantially. Although it is not a greenhouse gasrather low efficiency of about 50 percent. The (and, therefore, is not further considered in thisrest is estimated to enter the so-called nitrogen section), NO is involved in the formation processcascade (Galloway et al., 2003) and is transport- of ozone, which is a greenhouse gas.ed downstream or downwind where the nitrogen Though quickly re-deposited (hours to days),can have a sequence of effects on ecosystems annual atmospheric emissions of air-pollutingand people. Excessive nitrogen additions can ammonia (NH3) increased from some 18.8 mil-pollute ecosystems and alter both their ecologi- lion tonnes N at the end of the 19th century tocal functioning and the living communities they about 56.7 million tonnes in the early 1990s.support. They are projected to rise to 116 million tonnes What poses a problem to the atmosphere is N/yr by 2050, giving rise to considerable air pol- 103
    • Livestock’s long shadowlution in a number of world regions (Galloway et Ammonia dissolves easily in water, and is veryal., 2004). This would be almost entirely caused reactive with acid compounds. Therefore, once inby food production and particularly by animal the atmosphere, ammonia is absorbed by watermanure. and reacts with acids to form salts. These salts Besides increased fertilizer use and agricul- are deposited again on the soil within hours totural nitrogen fixation, the enhanced N2O emis- days (Galloway et al., 2003) and they in turn cansions from agricultural and natural ecosystems have an impact on ecosystems.are also caused by increasing N deposition(mainly of ammonia). Whereas terrestrial eco- 3.3.1 Nitrogen emissions from feed-relatedsystems in the northern hemisphere are limited fertilizerby nitrogen, tropical ecosystems, currently an The estimated global NH3 volatilization lossimportant source of N2O (and NO), are often from synthetic N fertilizer use in the mid-1990slimited by phosphorus. Nitrogen fertilizer inputs totalled about 11 million tonnes N per year. Ofinto these phosphorus-limited ecosystems gen- this 0.27 million tonnes emanated from fertil-erate NO and N2O fluxes that are 10 to 100 times ized grasslands, 8.7 million tonnes from rainfedgreater than the same fertilizer addition to N- crops and 2.3 million tonnes from wetland ricelimited ecosystems (Hall and Matson, 1999). (FAO/IFA, 2001), estimating emissions in 1995). Soil N2O emissions are also regulated by Most of this occurs in the developing countriestemperature and soil moisture and so are like- (8.6 million tonnes N), nearly half of whichly to respond to climate changes (Frolking et in China. Average N losses as ammonia fromal., 1998). In fact, chemical processes involving synthetic fertilizer use is more than twice asnitrous oxides are extremely complex (Mosier et high (18 percent) in developing countries than inal., 2004). Nitrification – the oxidation of ammo- developed and transition countries (7 percent).nia to nitrite and then nitrate – occurs in essen- Most of this difference in loss rates is resultingtially all terrestrial, aquatic and sedimentary from higher temperatures and the dominantecosystems and is accomplished by specialized use of urea and ammonium bicarbonate in thebacteria. Denitrification, the microbial reduction developing world.of nitrate or nitrite to gaseous nitrogen with NO In developing countries about 50 percent ofand N2O as intermediate reduction compounds, the nitrogen fertilizer used is in the form of ureais performed by a diverse and also widely distrib- (FAO/IFA, 2001). Bouwman et al. (1997) estimateuted group of aerobic, heterotrophic bacteria. that NH3 emission losses from urea may be 25 The main use of ammonia today is in fertil- percent in tropical regions and 15 percent inizers, produced from non-reactive molecular temperate climates. In addition, NH3 emissionsnitrogen, part of which directly volatilizes. The may be higher in wetland rice cultivation thanlargest atmospheric ammonia emission overall in dryland fields. In China, 40–50 percent of thecomes from the decay of organic matter in soils. nitrogen fertilizer used is in the form of ammoni-The quantity of ammonia that actually escapes um bicarbonate, which is highly volatile. The NH3from soils into the atmosphere is uncertain; but loss from ammonium bicarbonate may be 30is estimated at around 50 million tonnes per percent on average in the tropics and 20 percentyear (Chameides and Perdue, 1997). As much as in temperate zones. By contrast, the NH3 loss23 million tonnes N of ammonia are produced from injected anhydrous ammonia, widely usedeach year by domesticated animals, while wild in the United States, is only 4 percent (Bouwmananimals contribute roughly 3 million tonnes N/yr et al., 1997).and human waste adds 2 million tonnes N/yr. What share of direct emissions from fertilizer104
    • Livestock’s role in climate change and air pollutioncan we attribute to livestock? As we have seen, and the share of production used for feed, givesa large share of the world’s crop production is a total of some 75 million hectares in 2002 (FAO,fed to animals and mineral fertilizer is applied to 2006b). This would amount to another 0.2 mil-much of the corresponding cropland. Intensively lion tonnes of N2O-N per year. Adding alfalfa andmanaged grasslands also receive a significant clovers would probably about double this figure,portion of mineral fertilizer. In Section 3.2.1 although there are no global estimates of theirwe estimated that 20 to 25 percent of mineral cultivated areas. Russelle and Birr (2004) forfertilizer use (about 20 million tonnes N) can example show that soybean and alfalfa togetherbe ascribed to feed production for the livestock harvest some 2.9 million tonne of fixed N insector. Assuming that the low loss rates of an the Mississippi River Basin, with the N2 fixationimportant “fertilizer for feed” user such as the rate of alfalfa being nearly twice as high as thatUnited States is compensated by high loss rates of soybean (see also a review in Smil, 1999). Itin South and East Asia, the average mineral fer- seems therefore probable that livestock produc-tilizer NH3 volatilization loss rate of 14 percent tion can be considered responsible for a total(FAO/IFA, 2001) can be applied. On this basis, N2O-N emission from soils under leguminouslivestock production can be considered respon- crops exceeding 0.5 million tonnes per year andsible for a global NH3 volatilization from mineral a total emission from feedcropping exceeding 0.7fertilizer of 3.1 million tonnes NH3-N (tonnes of million tonne N2O-N.nitrogen in ammonia form) per year. Turning now to N2O, the level of emissions 3.3.2 Emissions from aquatic sourcesfrom mineral N fertilizer application depends following chemical fertilizer useon the mode and timing of fertilizer applica- The above direct cropland emissions representtion. N2O emissions for major world regions can some 10 to 15 percent of the anthropogenic,be estimated using the FAO/IFA (2001) model. added reactive N (mineral fertilizer and cultiva-Nitrous oxide emissions amount to 1.25 ± 1 tion-induced biological nitrogen fixation – BNF).percent of the nitrogen applied. This estimate is Unfortunately, a very large share of the remain-the average for all fertilizer types, as proposed ing N is not incorporated in the harvested plantby Bouwman (1995) and adopted by IPCC (1997). tissue nor stored in the soil. Net changes in theEmission rates also vary from one fertilizer organically bound nitrogen pool of the world’stype to another. The FAO/IFA (2001) calculations agricultural soils are very small and may beresult in a mineral fertilizer N2O-N loss rate of positive or negative (plus or minus 4 million1 percent. Under the same assumptions as for tonnes N, see Smil, 1999). Soils in some regionsNH3 above, livestock production can be consid- have significant gains whereas poorly managedered responsible for a global N2O emission from soils in other regions suffer large losses.mineral fertilizer of 0.2 million tonne N2O-N per As Von Liebig noted back in 1840 (cited in Smil,year. 2002) one of agriculture’s main objectives is to There is also N2O emission from leguminous produce digestible N, so cropping aims to accu-feedcrops, even though they do not generally mulate as much N as possible in the harvestedreceive N fertilizer because the rhizobia in their product. But even modern agriculture involvesroot nodules fix nitrogen that can be used by substantial losses – N efficiency in global cropthe plant. Studies have demonstrated that such production is estimated to be only 50 or 60 per-crops show N2O emissions of the same level as cent (Smil, 1999; van der Hoek, 1998). Rework-those of fertilized non-leguminous crops. Con- ing these estimates to express efficiency as thesidering the world area of soybean and pulses, amount of N harvested from the world’s cropland 105
    • Livestock’s long shadowwith respect to the annual N input,10 results in an ecosystems with reactive N results in emissionseven lower efficiency of some 40 percent. not only of N2, but also nitrous oxide. Galloway et This result is affected by animal manure, which al. (2004) estimate the total anthropogenic N2Ohas a relatively high loss rate as compared to emission from aquatic reservoirs to equal somemineral fertilizer (see following section). Mineral 1.5 million tonnes N, originating from a total offertilizer is more completely absorbed, depend- some 59 million tonnes N transported to inlanding on the fertilizer application rate and the type waters and coastal areas. Feed and forage pro-of mineral fertilizer. The most efficient combina- duction induces a loss of N to aquatic sources oftion reported absorbed nearly 70 percent. Min- some 8 to 10 million tonnes yr-1 if one assumeseral fertilizer absorption is typically somewhat such losses to be in line with N-fertilizationabove 50 percent in Europe, while the rates for shares of feed and forage production (someAsian rice are 30 to 35 percent (Smil, 1999). 20‑25 percent of the world total, see carbon sec- The rest of the N is lost. Most of the N losses tion). Applying the overall rate of anthropogenicare not directly emitted to the atmosphere, but aquatic N2O emissions (1.5/59) to the livestockenter the N cascade through water. The share of induced mineral fertilizer N loss to aquaticlosses originating from fertilized cropland is not reservoirs results in a livestock induced emis-easily identified. Smil (1999) attempted to derive sions from aquatic sources of around 0.2 milliona global estimate of N losses from fertilized tonnes N N2O.cropland. He estimates that globally, in the mid-1990, some 37 million tonnes N were exported 3.3.3 Wasting of nitrogen in the livestockfrom cropland through nitrate leaching (17 mil- production chainlion tonnes N) and soil erosion (20 tonnes N). In The efficiency of N assimilation by crops leavesaddition, a fraction of the volatilized ammonia much to be desired. To a large extent this lowfrom mineral fertilizer N (11 million tonnes N efficiency is owing to management factors, suchyr -1) finally also reaches the surface waters after as the often excessive quantity of fertilizersdeposition (some 3 million tonnes N yr-1). applied, as well as the form and timing of appli- This N is gradually denitrified in subsequent cations. Optimizing these parameters can resultreservoirs of the nitrogen cascade (Galloway et in an efficiency level as high as 70 percent. Theal., 2003). The resulting enrichment of aquatic remaining 30 percent can be viewed as inherent (unavoidable) loss. The efficiency of N assimilation by livestock is10 Cropproduction, as defined by van der Hoek, includes pas- even lower. There are two essential differences tures and grass. Reducing inputs and outputs of the N bal- between N in animal production and N in crop ance to reflect only the cropland balance (animal manure N down to 20 million tonnes N as in FAO/IFA, 2001; Smil, 1999, N use the: and removing the consumed grass N output) results in a crop • overall assimilation efficiency is much lower; product assimilation efficiency of 38 percent. Smil’s definition and of cropland N recovery rates is less broad, but it does include • wasting induced by non-optimal inputs is forage crops. Forage crops contain many leguminous spe- cies and, therefore, improve the overall efficiency. Removing generally lower. them from the balance appears to have only a minor effect. Though, Smil expresses recovery as the N contained in the As a result the inherent N assimilation effi- entire plant tissue. A substantial part of this is not harvested (he estimates crop residues to contain 25 million tonnes N): ciency of animal products is low leading to high some of this is lost upon decomposition after crop harvest N wasting under all circumstances. and some (14 million tonnes N) re-enters the following crop- N enters livestock through feed. Animal feeds ping cycle. Removing crop residues from the balance gives a harvested crop N recovery efficiency of 60/155 million tonnes contain 10 to 40 grams of N per kilogram of dry N= 38 percent. matter. Various estimates show livestock’s low106
    • Livestock’s role in climate change and air pollutionefficiency in assimilating N from feed. Aggregat- used as organic fertilizer, or directly depositeding all livestock species, Smil (1999) estimated on grassland or crop fields, some of the reac-that in the mid-1990s livestock excreted some tive N re-enters the crop production cycle. This75 million tonnes N. Van der Hoek (1998) esti- is particularly the case for ruminants, therefore,mates that globally livestock products contained their contribution to overall N loss to the envi-some 12 million tonnes N in 1994. These figures ronment is less than their contribution to N insuggest an underlying assimilation efficiency of animal waste. Smil (2002) also noted that “thisonly 14 percent. Considering only crop-fed ani- (ruminant assimilation: ed.) inefficiency is irrel-mal production, Smil (2002) calculated a similar evant in broader N terms as long as the animalsaverage efficiency of 15 percent (33 million (ruminants: ed.) are totally grass-fed, or raisedtonnes N from feed, forage and residues pro- primarily on crop and food processing residuesducing 5 million tonnes of animal food N). NRC (ranging from straw to bran and from oilseed(2003) estimated the United States livestock cakes to grapefruit rinds) that are indigestiblesector’s N assimilation efficiency also at 15 or unpalatable for non-ruminant species. Suchpercent (0.9 over 5.9 million tonne N). According cattle feeding calls for no, or minimal – becauseto the IPCC (1997), the retention of nitrogen in some pastures are fertilized – additional inputsanimal products, i.e., milk, meat, wool and eggs, of fertilizer-N. Any society that would put a pre-generally ranges from about 5 to 20 percent of mium on reducing N losses in agro-ecosystemsthe total nitrogen intake. This apparent homo- would thus produce only those two kinds of beef.geneity of estimations may well hide different In contrast, beef production has the greatestcauses such as low feed quality in semi-arid impact on overall N use when the animals are fedgrazing systems and excessively N-rich diets in only concentrates, which are typically mixtures ofintensive systems. cereal grains (mostly corn) and soybeans”. Efficiency varies considerably between different Significant emissions of greenhouse gases toanimal species and products. According to esti- the atmosphere do arise from losses of N frommates by Van der Hoek (1998) global N efficiency animal waste that contain large amounts of N andis around 20 percent for pigs and 34 percent for have a chemical composition which induces verypoultry. For the United States, Smil (2002) cal- high loss rates. For sheep and cattle, faecal excre-culated the protein conversion efficiency of dairy tion is usually about 8 grams of N per kilogram ofproducts at 40 percent, while that of beef cattle is dry matter consumed, regardless of the nitrogenonly 5 percent. The low N efficiency of cattle on content of the feed (Barrow and Lambourne,a global scale is partly inherent, given they are 1962). The remainder of the nitrogen is excretedlarge animals with long gestation periods and a in the urine, and as the nitrogen content of thehigh basal metabolic rate. But the global cattle diet increases, so does the proportion of nitrogenherd also comprises a large draught animal in the urine. In animal production systems wherepopulation whose task is to provide energy, not the animal intake of nitrogen is high, more thanprotein. For example, a decade ago cattle and half of the nitrogen is excreted as urine.horses still accounted for 25 percent of China’s Losses from manure occur at different stages:agricultural energy consumption (Mengjie and during storage; shortly after application or directYi, 1996). In addition, in many areas of the world, deposition to land and losses at later stages.grazing animals are fed at bare maintenancelevel, consuming without producing much. 3.3.4 Nitrogen emissions from stored As a result, a huge amount of N is returned manureto the environment through animal excretions. During storage (including the preceding excre-However, not all this excreted N is wasted. When tion in animal houses) the organically bound 107
    • Livestock’s long shadownitrogen in faeces and urine starts to mineralize in waste emitted to the atmosphere as nitrousto NH3/NH4+, providing the substrate for nitrifiers oxide), losses from animal waste during stor-and denitrifiers (and hence, eventual production age range from less than 0.0001 kg N2O N/kgof N2O). For the most part, these excreted N N for slurries to more than 0.15 kg N2O N/kgcompounds mineralize rapidly. In urine, typically nitrogen in the pig waste of deep-litter stables.over 70 percent of the nitrogen is present as urea Any estimation of global manure emission needs(IPCC, 1997). Uric acid is the dominant nitrogen to consider these uncertainties. Expert judge-compound in poultry excretions. The hydrolysis ment, based on existing manure management inof both urea and uric acid to NH3/NH4+ is very different systems and world regions, combinedrapid in urine patches. with default IPCC emission factors (Box 3.3),11 Considering first N2O emissions, generally suggests N2O emissions from stored manureonly a very small portion of the total nitrogen equivalent to 0.7 million tonnes N yr-1.excreted is converted to N2O during handling Turning to ammonia, rapid degradation ofand storage of managed waste. As stated above, urea and uric acid to ammonium leads to verythe waste composition determines its potential significant N losses through volatilization dur-mineralization rate, while the actual magni- ing storage and treatment of manure. Whiletude of N2O emissions depend on environmental actual emissions are subject to many factors,conditions. For N2O emissions to occur, the particularly the manure management systemwaste must first be handled aerobically, allowing and ambient temperature, most of the NH3 Nammonia or organic nitrogen to be converted to volatilizes during storage (typically about one-nitrates and nitrites (nitrification). It must then third of initially voided N), and before applicationbe handled anaerobically, allowing the nitrates or discharge. Smil (1999) (Galloway et al., 2003and nitrites to be reduced to N2, with interme- used Smil’s paper for estimate) estimate thatdiate production of N2O and nitric oxide (NO) globally about 10 million tonnes of NH3 N were(denitrification). These emissions are most likely lost to the atmosphere from confined animalto occur in dry waste-handling systems, which feeding operations in the mid 1990s. Although,have aerobic conditions, and contain pockets of only a part of all collected manure originatesanaerobic conditions owing to saturation. For from industrial systems.example, waste in dry lots is deposited on soil, On the basis of the animal population in indus-where it is oxidized to nitrite and nitrate, and has trial systems (Chapter 2), and their estimatedthe potential to encounter saturated conditions. manure production (IPCC, 1997), the currentThere is an antagonism between emission risks amount of N in the corresponding animal wasteof methane versus nitrous oxide for the different can be estimated at 10 million tonnes, and thewaste storage pathways – trying to reduce meth- corresponding NH3 volatilization from storedane emissions may well increase those of N2O. manure at 2 million tonnes N. The amount of N2O released during storage Thus, volatilization losses during animal wasteand treatment of animal wastes depends onthe system and duration of waste managementand the temperature. Unfortunately, there is 11 See also Annex 3.3. Regional livestock experts provided information on the relative importance of different wastenot enough quantitative data to establish a rela- management systems in each of the region’s productiontionship between the degree of aeration and systems through a questionnaire. On the basis of this infor-N2O emission from slurry during storage and mation, waste management and gaseous emission experts from the Recycling of Agricultural, Municipal and Indus-treatment. Moreover, there is a wide range of trial Residues in Agriculture Network (RAMIRAN; availableestimates for the losses. When expressed in N2O at www.ramiran.net) estimated region and system specificN/kg nitrogen in the waste (i.e. the share of N emissions.108
    • Livestock’s role in climate change and air pollutionmanagement are not far from those from current Added to this, according to FAO/IFA (2001) thesynthetic N fertilizer use. On the one hand, this post application loss of managed animal manurenitrogen loss reduces emissions from manure was about 8 million tonnes N, resulting in aonce applied to fields; on the other, it gives rise total ammonia volatilization N loss from animalto nitrous oxide emissions further down the manure on land of around 20 million tonnes N.“nitrogen cascade.” These figures have increased over the past decade. Even following the very conservative3.3.5 Nitrogen emissions from applied or IPCC ammonia volatilization loss fraction of 20deposited manure percent and subtracting manure used as for fuelExcreta freshly deposited on land (either applied results in an estimated NH3 volatilization lossby mechanical spreading or direct deposition following manure application/deposition of someby the livestock) have high nitrogen loss rates, 25 million tonnes N in 2004.resulting in substantial ammonia volatiliza- Turning now to N2O, the soil emissions origi-tion. Wide variations in the quality of forages nating from the remaining external nitrogenconsumed by ruminants and in environmental input (after subtraction of ammonia volatiliza-conditions make N emissions from manure on tion) depend on a variety of factors, particularlypastures difficult to quantify. FAO/IFA (2001) soil water filled pore space, organic carbon avail-estimate the N loss via NH3 volatilization from ability, pH, soil temperature, plant/crop uptakeanimal manure, after application, to be 23 per- rate and rainfall characteristics (Mosier et al.,cent worldwide. Smil (1999) estimates this loss 2004). However, because of the complex inter-to be at least 15–20 percent. action and the highly uncertain resulting N2O The IPCC proposes a standard N loss fraction flux, the revised IPCC guidelines are based on Nfrom ammonia volatilization of 20 percent, with- inputs only, and do not consider soil character-out differentiating between applied and directly istics. Despite this uncertainty, manure-induceddeposited manure. Considering the substantial soil emissions are clearly the largest livestockN loss from volatilization during storage (see source of N2O worldwide. Emission fluxes frompreceding section) the total ammonia volatil- animal grazing (unmanaged waste, direct emis-ization following excretion can be estimated at sion) and from the use of animal waste as fertil-around 40 percent. It seems reasonable to apply izer on cropland are of a comparable magni-this rate to directly deposited manure (maxi- tude. The grazing-derived N2O emissions are inmum of 60 percent or even 70 percent have been the range of 0.002–0.098 kg N2O–N/kg nitrogenrecorded), supposing that the lower share of N in excreted, whereas the default emission fac-urine in tropical land-based systems is compen- tor used for fertilizer use is set at 0.0125 kgsated by the higher temperature. We estimate N2O–N/kg nitrogen. Nearly all data pertain tothat in the mid-1990s around 30 million tonnes temperate areas and to intensively managedof N was directly deposited on land by animals in grasslands. Here, the nitrogen content of dung,the more extensive systems, producing an NH3 and especially urine, are higher than from lessvolatilization loss of some 12 million tonnes N.12 intensively managed grasslands in the tropics or subtropics. It is not known to what extent this compensates for the enhanced emissions in the12 From the estimated total of 75 million tonnes N excreted by more phosphorus-limited tropical ecosystems. livestock we deduce that 33 million tonnes were applied to Emissions from applied manure must be cal- intensively used grassland, upland crops and wetland rice culated separately from emissions from waste (FAO/IFA, 2001) and there were 10 million tonnes of ammo- nia losses during storage. Use of animal manure as fuel is excreted by animals. The FAO/IFA study (2001) ignored. estimates the N2O loss rate from applied manure 109
    • Livestock’s long shadow Box 3.3 A new assessment of nitrous oxide emissions from manure by production system, species and region The global figures we have cited demonstrate the Our estimates of N2O emissions from manure importance of nitrous oxide emissions from animal and soils are the result of combining current live- production. However, to set priorities in addressing stock production and population data (Groenewold, the problem, we need a more detailed understand- 2005) with the IPCC methodology (IPCC, 1997). ing of the origin of these emissions, by evaluating Deriving N2O emissions from manure management the contribution of different production systems, requires a knowledge of: species and world regions to the global totals. • N excretion by livestock type, Our assessment, detailed below, is based on • the fraction of manure handled in each of the current livestock data and results in a much different manure management systems, and higher estimate than most recent literature, which • an emission factor (per kg N excreted) for each is based on data from the mid-1990s. The live- of the manure management systems. stock sector has evolved substantially over the The results are summed for each livestock spe- last decade. We estimate a global N excretion of cies within a world region/production system (see some 135 million tonnes per year, whereas recent Chapter 2) and multiplied by N excretion for that literature (e.g. Galloway et al., 2003) still cites an livestock type to derive the emission factor for N2O estimate of 75 million tonnes yr -1 derived from per head. mid-1990s data. Table 3.11 Estimated total N2O emission from animal excreta in 2004 N2O emissions from manure management, after application/deposition on soil and direct emissions Region/country Dairy cattle Other cattle Buffalo Sheep and goats Pigs Poultry Total (.................................................. million tonnes per year ..................................................) Sub-Saharan Africa 0.06 0.21 0.00 0.13 0.01 0.02 0.43 Asia excluding China and India 0.02 0.14 0.06 0.05 0.03 0.05 0.36 India 0.03 0.15 0.06 0.05 0.01 0.01 0.32 China 0.01 0.14 0.03 0.10 0.19 0.10 0.58 Central and South America 0.08 0.41 0.00 0.04 0.04 0.05 0.61 West Asia and North Africa 0.02 0.03 0.00 0.09 0.00 0.03 0.17 North America 0.03 0.20 0.00 0.00 0.04 0.04 0.30 Western Europe 0.06 0.14 0.00 0.07 0.07 0.03 0.36 Oceania and Japan 0.02 0.08 0.00 0.09 0.01 0.01 0.21 Eastern Europe and CIS 0.08 0.10 0.00 0.03 0.04 0.02 0.28 Other developed 0.00 0.03 0.00 0.02 0.00 0.00 0.06 Total 0.41 1.64 0.17 0.68 0.44 0.36 3.69 Livestock Production System Grazing 0.11 0.54 0.00 0.25 0.00 0.00 0.90 Mixed 0.30 1.02 0.17 0.43 0.33 0.27 2.52 Industrial 0.00 0.08 0.00 0.00 0.11 0.09 0.27 Source: Own calculations.110
    • Livestock’s role in climate change and air pollution Box 3.3 (cont.) Direct emissions resulting from manure applica- sive and intensive systems emissions from manure tions (and grazing deposits) to soils were derived are dominated by soil emissions. Among soil emis- using the default emission factor for N applied sions, emissions from manure management are to land (0.0125 kg N2O-N/kg N). To estimate the more important. The influence of the character- amount of N applied to land, N excretion per live- istics of different production systems is rather stock type was reduced allowing for the estimated limited. The strong domination of N2O emissions fraction lost as ammonia and/or nitrogen oxides by mixed livestock production systems is related during housing and storage, the fraction deposited in a rather linear way to the relative numbers of directly by grazing livestock, and the fraction used the corresponding animals. Large ruminants are as fuel. responsible for about half the total N2O emissions The results of these calculations (Table 3.11) from manure. show that emissions originating from animal Map 33 (Annex 1) presents the distribution manure are much higher than any other N2O emis- among the world regions of the N2O emissions of sions caused by the livestock sector. In both exten- the different production systems.at 0.6 percent,13 i.e. lower than most mineral N from mixed and 0.1 million tonnes from indus-fertilizers, resulting in an animal manure soil trial production systems (see Box 3.3).N2O loss in the mid 1990s of 0.2 million tonnes N.Following the IPCC methodology would increase 3.3.6 Emissions following manure this to 0.3 million tonnes N. nitrogen losses after application and Regarding animal waste excreted in pastures, direct depositiondung containing approximately 30 million tonnes In the mid-1990s, after losses to the atmosphereN was deposited on land in the more extensive during storage and following application andsystems in the mid-1990s. Applying the IPCC direct deposition, some 25 million tonnes of“overall reasonable average emission factor” nitrogen from animal manure remained available(0.02 kg N2O–N/kg of nitrogen excreted) to this per year for plant uptake in the world’s crop-total results in an animal manure soil N2O lands and intensively used grasslands. Uptakeloss of 0.6 million tonne N, making a total N2O depends on the ground cover: legume/grassemission of about 0.9 million tonnes N in the mixtures can take up large amount of added N,mid-1990s. whereas loss from row crops14 is generally sub- Applying the IPCC methodology to the current stantial, and losses from bare/ploughed soil areestimate of livestock production system and much higher still.animal numbers results in an overall “direct” If we suppose that N losses in grassland,animal manure soil N2O loss totalling 1.7 mil- through leaching and erosion, are negligible,lion tonnes N per year. Of this, 0.6 million tonnes and apply the crop N use efficiency of 40 percentderive from grazing systems, 1.0 million tonnes to the remainder of animal manure N applied13 Expressed as a share of the initially applied amount, without deduction of the on-site ammonia volatilization, which may 14 Agricultural crops, such as corn and soybeans, that are explain why the IPCC default is higher. grown in rows. 111
    • Livestock’s long shadowto cropland,15 then we are left with some 9 or overall impact on climate change by: major gas,10 million tonnes N that mostly entered the N source and type of production system.cascade through water in the mid-1990s. Apply- Here we will summarize the impact for theing the N2O loss rate for subsequent N2O emis- three major greenhouse gases.sion (Section 3.3.2) gives us an estimate of anadditional emission of some 0.2 million tonne N Carbon dioxideN2O from this channel. N2O emissions of similar Livestock account for 9 percent of globalsize can be expected to have resulted from the anthropogenic emissionsre-deposited fraction of the volatilized NH3 from When deforestation for pasture and feedcropmanure that reached the aquatic reservoirs in land, and pasture degradation are taken intothe mid-1990s.16 Total N2O emissions follow- account, livestock-related emissions of carboning N losses would, therefore, have been in the dioxide are an important component of the glob-order of 0.3­0.4 million tonnes N N2O per year in al total (some 9 percent). However, as can bethat period. seen from the many assumptions made in pre- We have updated these figures for the current ceding sections, these totals have a considerablelivestock production system estimates, using degree of uncertainty. LULUCF sector emissionsthe IPCC methodology for indirect emissions. in particular are extremely difficult to quantifyThe current overall “indirect” animal manure and the values reported to the UNFCCC for thisN2O emission following volatilization and leach- sector are known to be of low reliability. Thising would then total around 1.3 million tonnes sector is therefore often omitted in emissionsN per year. However, this methodology is beset reporting, although its share is thought to bewith high uncertainties, and may lead to an important.overestimation because manure during grazing Although small by comparison to LULUCF,is considered. The majority of N2O emissions, or the livestock food chain is becoming more fos-about 0.9 million tonnes N, would still originate sil fuel intensive, which will increase carbonfrom mixed systems. dioxide emissions from livestock production. As ruminant production (based on traditional local3.4 Summary of livestock’s impact feed resources) shifts to intensive monogastricsOverall, livestock activities contribute an esti- (based on food transported over long distances),mated 18 percent to total anthropogenic green- there is a corresponding shift away from solarhouse gas emissions from the five major sectors energy harnessed by photosynthesis, to fossilfor greenhouse gas reporting: energy, industry, fuels.waste, land use, land use change and forestry(LULUCF) and agriculture. Methane Considering the last two sectors only, livestock’s Livestock account for 35–40 percent of globalshare is over 50 percent. For the agriculture sec- anthropogenic emissionstor alone, livestock constitute nearly 80 percent of The leading role of livestock, in methane emis-all emissions. Table 3.12 summarizes livestock’s sions, has long been a well-established fact. Together, enteric fermentation and manure rep-15 FAO/IFA resent some 80 percent of agricultural methane (2001) data on animal manure application to crop- land, diminished by the FAO/IFA N volatilization and emission emissions and about 35–40 percent of the total estimates. anthropogenic methane emissions.16 Applying the same N O loss rate for subsequent emission to 2 With the decline of ruminant livestock in rela- the roughly 6 million tonnes N reaching the aquatic reser- voirs out of the total of 22 million tonnes manure N volatilized tive terms, and the overall trend towards higher as NH3 in the mid-1990s according to the literature. productivity in ruminant production, it is unlikely112
    • Livestock’s role in climate change and air pollutionTable 3.12Role of livestock in carbon dioxide, methane and nitrous oxide emissions Gas Source Mainly Mainly Percentage related to related to contribution extensive intensive to total systems systems animal food (109 tonnes CO2 eq.) (109 tonnes CO2 eq.) GHG emissions CO2 Total anthropogenic CO2 emissions 24 (~31) Total from livestock activities ~0.16 (~2.7) N fertilizer production 0.04 0.6 on farm fossil fuel, feed ~0.06 0.8 on farm fossil fuel, livestock-related ~0.03 0.4 deforestation (~1.7) (~0.7) 34 cultivated soils, tillage (~0.02) 0.3 cultivated soils, liming (~0.01) 0.1 desertification of pasture (~0.1) 1.4 processing 0.01 – 0.05 0.4 transport ~0.001 CH4 Total anthropogenic CH4 emissions 5.9 Total from livestock activities 2.2 enteric fermentation 1.6 0.20 25 manure management 0.17 0.20 5.2 N2O Total anthropogenic N2O emissions 3.4 Total from livestock activities 2.2 N fertilizer application ~0.1 1.4 indirect fertilizer emission ~0.1 1.4 leguminous feed cropping ~0.2 2.8 manure management 0.24 0.09 4.6 manure application/deposition 0.67 0.17 12 indirect manure emission ~0.48 ~0.14 8.7 Grand total of anthropogenic emissions 33 (~40) Total emissions from livestock activities ~4.6 (~7.1) Total extensive vs. intensive livestock system emissions 3.2 (~5.0) 1.4 (~2.1) Percentage of total anthropogenic emissions 10 (~13%) 4 (~5%) Note: All values are expressed in billion tonnes of CO2 equivalent; values between brackets are or include emission from the land use,land-use change and forestry category; relatively imprecise estimates are preceded by a tilde.Global totals from CAIT, WRI, accessed 02/06. Only CO2, CH4 and N2O emissions are considered in the total greenhouse gas emis-sion.Based on the analyses in this chapter, livestock emissions are attributed to the sides of the production system continuum (fromextensive to intensive/industrial) from which they originate. 113
    • Livestock’s long shadowthat the importance of enteric fermentation will to be understood in a local context. In Brazil, forincrease further. However, methane emissions example, carbon dioxide emissions from land-from animal manure, although much lower in use change (forest conversion and soil organicabsolute terms, are considerable and growing matter loss) are reported to be much higherrapidly. than emissions from the energy sector. At the same time, methane emissions from enteric fer-Nitrous oxide mentation strongly dominate the country’s totalLivestock account for 65 percent of global methane emission, owing to the extensive beefanthropogenic emissions cattle population. For this same reason pastureLivestock activities contribute substantially to soils produce the highest nitrous oxide emissionsthe emission of nitrous oxide, the most potent in Brazil, with an increasing contribution fromof the three major greenhouse gases. They con- manure. If livestock’s role in land-use change istribute almost two-thirds of all anthropogenic included, the contribution of the livestock sectorN2O emissions, and 75–80 percent of agricul- to the total greenhouse gas emission of this verytural emissions. Current trends suggest that this large country can be estimated to be as high aslevel will substantially increase over the coming 60 percent, i.e. much higher than the 18 percentdecades. at world level (Table 3.12).Ammonia 3.5 Mitigation optionsLivestock account for 64 percent of global Just as the livestock sector makes large andanthropogenic emissions multiple contributions to climate change andGlobal anthropogenic atmospheric emission of air pollution, so there are multiple and effectiveammonia has recently been estimated at some options for mitigation. Much can be done, but to47 million tonnes N (Galloway et al., 2004). Some get beyond a “business as usual” scenario will94 percent of this is produced by the agricultural require a strong involvement of public policy.sector. The livestock sector contributes about Most of the options are not cost neutral – simply68 percent of the agriculture share, mainly from enhancing awareness will not lead to widespreaddeposited and applied manure. adoption. Moreover, by far the largest share of The resulting air and environmental pollution emissions come from more extensive systems,(mainly eutrophication, also odour) is more a where poor livestock holders often extract mar-local or regional environmental problem than a ginal livelihoods from dwindling resources andglobal one. Indeed, similar levels of N deposi- lack the funds to invest in change. Change is ations can have substantially different environ- matter of priority and vision, of making short-mental effects depending on the type of eco- term expenses (for compensation or creation ofsystem they affect. The modelled distribution of alternatives) for long-term benefits.atmospheric N deposition levels (Figure 3.3) are We will examine the policy aspects in Chap-a better indication of the environmental impact ter 6. Here we explore the main technical options,than the global figures. The distribution shows a including those for substantially reducing thestrong and clear co-incidence with intensive live- major current emissions and those that will cre-stock production areas (compare with Map 13). ate or expand substantial sinks. The figures presented are estimates for the Globally climate change is strongly associatedoverall global-level greenhouse gas emissions. with carbon dioxide emissions, which representHowever, they do not describe the entire issue roughly three quarters of the total anthropogenicof livestock-induced change. To assist decision- emissions. Because the energy sector accountsmaking, the level and nature of emissions need for about three-quarters of anthropogenic CO2,114
    • Livestock’s role in climate change and air pollution Figure 3.3 Spatial pattern of total inorganic nitrogen deposition in the early 1990s 60N 5 000 2 000 1 000 30N 750 500 EQ 250 100 50 30S 25 5 60S 180W 120W 60W 0 60E 120E 180E Note: Units – mg N per square metre per year. Source: Galloway et al., (2004).limited attention has been paid to reducing addressing issues of land-use change and landemissions of other gases from other sectors. In degradation. Here the livestock sector offers aa development context, particularly, this is not significant potential for carbon sequestration,justified. While developing countries account for particularly in the form of improved pastures.only 36 percent of CO2 emissions, they producemore than half of N2O and nearly two-thirds of Reducing deforestation by agriculturalCH4. It is therefore surprising to see that even in intensificationthe case of a large country such as Brazil, most When it comes to land-use change, the chal-mitigation efforts focus on the energy sector. lenge lies in slowing and eventually halting and reversing deforestation. The still largely uncon-3.5.1 Sequestering carbon and mitigating trolled process urgently needs to be consciouslyCO2 emissions planned, on the basis of trade-offs between ben-Compared to the amounts of carbon released efits and costs at different spatial and temporalfrom changes in land use and land-degradation, scales. Amazon deforestation, related to agri-emissions from the food chain are small. So cultural expansion for livestock, has been dem-for CO2 the environmental focus needs to be on onstrated to contribute substantially to global 115
    • Livestock’s long shadowanthropogenic carbon dioxide emissions. The sequestration of carbon in cultivated soils. Theforecast increase in emissions could be curtailed carbon sink capacity of the world’s agriculturalif development strategies were implemented to and degraded soils is 50 to 66 percent of thecontrol frontier expansion and create economic historic carbon loss from soils of 42 to 78 giga-alternatives (Carvalho et al., 2004). tons of carbon (Lal, 2004a). In addition, carbon Creating incentives for forest conservation sequestration has the potential to enhance foodand decreased deforestation, in Amazonia and security and to offset fossil fuel emissions.other tropical areas, can offer a unique oppor- Soil processes, with respect to carbon, aretunity for climate change mitigation, especially characterized by the dynamic equilibrium ofgiven the ancillary benefits (see Chapter 6 on input (photosynthesis) and output (respiration).policies) and relative low costs. Any programme Under conventional cultivation practices, thethat aims to set aside land for the purpose of conversion of natural systems to cultivated agri-sequestering carbon must do so without threat- culture results in losses of soil organic carbonening food security in the region. Vlek et al. (SOC) on the order of 20 to ­50 percent of the pre-(2004) consider that the only available option to cultivation stocks in the top one metre (Paustianfree up the land necessary for carbon seques- et al., 1997; Lal and Bruce, 1999).tration would be intensification of agricultural Changing environmental conditions and landproduction on some of the better lands, for management may induce a change in the equi-example by increased fertilizer inputs. They librium to a new level that is considered stable.demonstrate that the increased carbon dioxide There are now proven new practices that canemissions related to the extra fertilizer produc- improve soil quality and raise soil organic carbontion would be far outweighed by the seques- levels. The full potential for terrestrial soil car-tered or avoided emissions of organic carbon bon sequestration is uncertain, because of insuf-related to deforestation. Increased fertilizer use ficient data and understanding of SOC dynamicsthough constitutes just one of many options for at all levels, including molecular, landscape,intensification. Others include higher-yielding, regional and global scales (Metting et al., 1999).better adapted varieties and improved land and According to the IPCC (2000) improved practiceswater management. Although rationally attrac- typically allow soil carbon to increase at a rate oftive, the “sequestration through intensification” about 0.3 tonnes of carbon per hectare per year.paradigm may not be effective in all socio-politi- If these practices were adopted on 60 percent ofcal contexts and imposes strong conditions on the available arable land worldwide, they wouldthe regulatory framework and its enforcement. result in a capture of about 270 million tonnes CWhere deforestation occurs, and where it is per year over the next few decades (Lal, 1997).accepted, care should be taken to quickly trans- It is unclear if this rate is sustainable: researchform the area into a sustainable agricultural shows a relatively rapid increase in carbonarea, for example by implementing practices sequestration for a period of about 25 years andlike silvo-pastoral systems (see Box 6.2, Chapter a gradual levelling thereafter (Lal et al., 1998).6) and conservation agriculture, thus preventing Non-conventional practices can be groupedirreversible damage. into three classes: agricultural intensification, conservation tillage, and erosion reduction.Restoring soil organic carbon to cultivated soils Examples of intensifying practices are improvedThe relatively low carbon dioxide emissions from cultivars, irrigation, organic and inorganic fertil-arable land leave little scope for significant ization, management of soil acidity, integratedmitigation. But there is a huge potential for net pest management, double-cropping, and crop116
    • Livestock’s role in climate change and air pollutionrotations including green manure and cover to intensive tillage or mould-board ploughingcrops. Increasing crop yields result in more car- can negate or offset any gains and restore thebon accumulated in crop biomass or in an altera- sequestered carbon to the atmosphere. Soil car-tion of the harvest index. The higher crop resi- bon sequestration can be even further increaseddues, sometimes associated with higher yields, when cover crops are used in combination withfavour enhanced soil carbon storage (Paustian conservation tillage.et al., 1997). Similar results have been reported from organ- IPCC (2000) provides an indication of the “car- ic farming,17 which has evolved since the earlybon gain rate” that can be obtained for some years of the twentieth century. Organic farmingpractices. increases soil organic carbon content. Additional Conservation tillage is any tillage and plant- benefits are reported such as reversing of landing system in which 30 percent, or more, of the degradation, increasing soil fertility and health.crop residue remains on the soil surface after Trials of maize and soybean reported in Vasiliki-planting. Generally it also comprises reduced otis (2001) demonstrated that organic systemsmechanical intervention during the cropping can achieve yields comparable to conventionalseason. Conservation tillage can include specific intensive systems, while also improving long-tillage types such as no-till, ridge-till, mulch-till, term soil fertility and drought resistance.zone-till, and strip-till systems, chosen by farm- These improved agriculture practices are alsoers to address soil type, crop grown, machinery the major components of sustainable agricul-available, and local practice. Although these ture and rural development as outlined in thesystems were originally developed to address UNCED Agenda 21 (Chapter 14). Although farm-problems of water quality, soil erosion and agri- ers’ adoption of these practices also createcultural sustainability, they also lead to higher on-farm benefits such as increased crop yields,soil organic carbon and increased fuel efficiency the adoption of such practices on a wider scale(owing to reduced use of machinery for soil cul- largely depends on the extent that farmers aretivation). Hence, at the same time, they increase faced with the environmental consequences ofcarbon sinks and reduce carbon emissions. their current practices. Farmers may also need Conservation tillage is achieving widespread additional knowledge and resources before theyadoption around the world. In 2001, a study will invest in such practices. Farmers will makeconducted by the American Soybean Association their own choices, depending on expected net(ASA) showed that a majority of the 500 000 soy- returns, in the context of existing agriculture andbean farmers in the United States had adopted environmental policies.conservation tillage practices following the intro-duction of herbicide-resistant soybeans (Nill, 17 Organicfarming is the outcome of theory and practice since2005). The resulting topsoil carbon increase also the early years of the twentieth century, involving a varietyenables the land to absorb increasing amounts of alternative methods of agricultural production mainly inof rainfall, with a corresponding reduction in northern Europe. There have been three important move-runoff and much better drought resistance com- ments: biodynamic agriculture, which appeared in Germany; organic farming, which originated in England; and biologicalpared to conventionally tilled soybeans. agriculture, which was developed in Switzerland. Despite The IPCC (2000) estimates that conservation some differences of emphasis, the common feature of alltillage can sequester 0.1–1.3 tonnes C ha-1 y-1 these movements is to stress the essential link between farming and nature, and to promote respect for naturalglobally, and could feasibly be adopted on up to equilibria. They distance themselves from the conventional60 percent of arable lands. These benefits accrue approach to farming, which maximizes yields through theonly if conservation tillage continues: a return use of various kinds of synthetic products. 117
    • Livestock’s long shadowTable 3.13 even longer than in forest soils. Although theGlobal terrestrial carbon sequestration potential rate at which carbon can be sequestered in thesefrom improved management regions is low, it may be cost-effective, particu-Carbon sink Potential sequestration larly taking into account all the side-benefits for (billion tonnes C per year) soil improvement and restoration (FAO, 2004b).Arable lands 0.85 – 0.90 Soil-quality improvement as a consequence ofBiomass crops for biofuel 0.5 – 0.8 increased soil carbon will have an importantGrassland and rangelands 1.7 social and economic impact on the livelihood ofForests 1–2 people living in these areas. Moreover, there isSource: adapted from Rice (1999). a great potential for carbon sequestration in dry lands because of their large extent and because substantial historic carbon losses mean thatReversing soil organic carbon losses from dryland soils are now far from saturation.degraded pastures Some 18–28 billion tonnes of carbon haveUp to 71 percent of the world’s grasslands were been lost as a result of desertification (see sec-reported to be degraded to some extent in 1991 tion on feed sourcing). Assuming that two-thirds(Dregne et al. 1991) as a result of overgraz- of this can be re-sequestered through soil anding, salinization, alkalinization, acidification, and vegetation restoration (IPCC, 1996), the poten-other processes. tial of C sequestration through desertification Improved grassland management is another control and restoration of soils is 12–18 billionmajor area where soil carbon losses can be tonnes C over a 50 year period (Lal, 2001, 2004b).reversed leading to net sequestration, by the use Lal (2004b) estimates that the “eco-technologi-of trees, improved species, fertilization and other cal” (maximum achievable) scope for soil carbonmeasures. Since pasture is the largest anthropo- sequestration in the dryland ecosystems may begenic land use, improved pasture management about 1 billion tonnes C yr-1, though he suggestscould potentially sequester more carbon than that realization of this potential would requireany other practice (Table 4-1, IPCC, 2000). There a “vigorous and a coordinated effort at a globalwould also be additional benefits, particularly scale towards desertification control, restorationpreserving or restoring biodiversity. It can yield of degraded ecosystems, conversion to appro-these benefits in many ecosystems. priate land uses, and adoption of recommended In the humid tropics silvo-pastoral sys- management practices on cropland and grazingtems (discussed in Chapter 6, Box 6.2) are one land.” Taking just the grasslands in Africa, ifapproach to carbon sequestration and pasture the gains in soil carbon stocks, technologicallyimprovement. achievable with improved management, were In dryland pastures soils are prone to degra- actually achieved on only 10 percent of the areadation and desertification, which have lead to concerned, this would result in a SOC gain rate ofdramatic reductions in the SOC pool (see Sec- 1 3­28 million tonnes C per year for some 25 yearstion 3.2.1 on livestock-related emissions from (Batjes, 2004). For Australian rangelands, whichcultivated soils) (Dregne, 2002). However, some occupy 70 percent of the country’s land mass,aspects of dryland soils may help in carbon the potential sequestration rate through bettersequestration. Dry soils are less likely to lose management has been evaluated at 70 millioncarbon than wet soils, as lack of water limits soil tonnes C per year (Baker et al., 2000).mineralization and therefore the flux of carbon Overgrazing is the greatest cause of degrada-to the atmosphere. Consequently, the residence tion of grasslands and the overriding human-time of carbon in dryland soils is sometimes influenced factor in determining their soil carbon118
    • Livestock’s role in climate change and air pollutionlevels. Consequently, in many systems, improved Despite the higher carbon gains that might comegrazing management, such as optimizing stock from agroforestry, Reid et al. (2004) estimatenumbers and rotational grazing, will result in that the returns per person are likely to be lowersubstantial increases in carbon pools (Table 4–6, in these systems because they principally occurIPCC, 2000). in higher-potential pastoral lands, where human Many other technical options exist, including population densities are 3–10 times higher thanfire management, protection of land, set-asides in drier pastoral lands. Payment schemes forand grassland production enhancement (e.g., fer- carbon sequestration through silvo-pastoral sys-tilization, introduction of deep-rooted and legume tems have already proven their viability in Latinspecies). Models exist to provide an indication American countries (see Box 6.2, Chapter 6).of the respective effects of these practices in a Unlocking the potential of mechanisms likeparticular situation. More severely degraded land carbon credit schemes is still a remote goal, notrequires landscape rehabilitation and erosion only requiring vigorous and coordinated effortcontrol. This is more difficult and costly, but Aus- on a global scale, but also the overcoming of atralian research reports considerable success in number of local obstacles. As illustrated by Reidrehabilitating landscape function by promoting et al. (2004), carbon credit schemes will requirethe rebuilding of patches (Baker et al., 2000). communication between groups often distant Because dryland conditions offer few eco- from one another, yet pastoral areas usuallynomic incentives to invest in land rehabilitation have less infrastructure and much lower popula-for agricultural production purposes, compen- tion density than higher potential areas. Culturalsation schemes for carbon sequestration may values may pose constraints but sometimesbe necessary to tip the balance in some situa- offer opportunities in pastoral lands. Finally thetions. A number of mechanisms stimulated by strength and ability of government institutionsthe UNFCCC are now operational (see Chapter required to implement such schemes is often6). Their potential may be high in pastoral dry insufficient in the countries and areas wherelands, where each household ranges livestock they are most needed.over large areas. Typical population densities inpastoral areas are 10 people per km2 or 1 person 3.5.2 Reducing CH4 emissions from per 10 ha. If carbon is valued at US$10 per tonne enteric fermentation through and modest improvements in management can improved efficiency and dietsgain 0.5 tonnes C/ha/yr, individuals might earn Methane emissions by ruminants are not only anUS$50 a year for sequestering carbon. About environmental hazard but also a loss of produc-half of the pastoralists in Africa earn less than tivity, since methane represents a loss of carbonUS$1 per day or about US$360 per year. Thus, from the rumen and therefore an unproductivemodest changes in management could augment use of dietary energy (US-EPA, 2005). Emissionsindividual incomes by 15 percent, a substantial per animal and per unit of product are higherimprovement (Reid et al., 2004). Carbon improve- when the diet is poor.ments might also be associated with increases The most promising approach for reducingin production, creating a double benefit. methane emissions from livestock is by improv- ing the productivity and efficiency of livestockCarbon sequestration through agroforestry production, through better nutrition and genet-In many situations agroforestry practices also ics. Greater efficiency means that a larger por-offer excellent, and economically viable, poten- tion of the energy in the animals’ feed is directedtial for rehabilitation of degraded lands and for toward the creation of useful products (milk,carbon sequestration (IPCC, 2000; FAO, 2000). meat, draught power), so that methane emis- 119
    • Livestock’s long shadowsions per unit product are reduced. The trend sions, because temperate pastures are likely totowards high performing animals and towards be higher in soluble carbohydrates and easilymonogastrics and poultry in particular, are valu- digestible cell wall components.able in this context as they reduce methane per For the United States, US-EPA (2005) reportsunit of product. The increase in production effi- that greater efficiency of livestock productionciency also leads to a reduction in the size of the has already led to an increase in milk productionherd required to produce a given level of product. while methane emissions decreased over theBecause many developing countries are striving last several decades. The potential for efficiencyto increase production from ruminant animals gains (and therefore for methane reductions) is(primarily milk and meat), improvements in pro- even larger for beef and other ruminant meatduction efficiency are urgently needed for these production, which is typically based on poorergoals to be realized without increasing herd management, including inferior diets. US-EPAsizes and corresponding methane emissions. (2005) lists a series of management measures A number of technologies exist to reduce that could improve a livestock operation’s pro-methane release from enteric fermentation. The duction efficiency and reduce greenhouse gasbasic principle is to increase the digestibility of emissions, including:feedstuff, either by modifying feed or by manipu- • improving grazing management;lating the digestive process. Most ruminants in • soil testing, followed by addition of properdeveloping countries, particularly in Africa and amendments and fertilizers;South Asia, live on a very fibrous diet. Techni- • supplementing cattle diets with needed nutri-cally, the improvement of these diets is relatively ents;easy to achieve through the use of feed additives • developing a preventive herd health pro-or supplements. However, such techniques are gramme;often difficult to adopt for smallholder livestock • providing appropriate water sources and pro-producers who may lack the necessary capital tecting water quality; andand knowledge. • improving genetics and reproductive efficien- In many instances, such improvements may cy.not be economical, for example where there isinsufficient demand or infrastructure. Even in a When evaluating techniques for emissioncountry like Australia, low-cost dairy production reduction it is important to recognize that feedfocuses on productivity per hectare rather than and feed supplements used to enhance produc-per cow, so many options for reducing emissions tivity may well involve considerable greenhouseare unattractive – e.g. dietary fat supplementa- gas emissions to produce them, which will affecttion or increased grain feeding (Eckard et al., the balance negatively. If production of such2000). Another technical option is to increase feed stuffs is to increase substantially, optionsthe level of starch or rapidly fermentable car- to reduce emissions at feed production level willbohydrates in the diet, so as to reduce excess also need to be considered.hydrogen and subsequent CH4 formation. Again More advanced technologies are also beinglow-cost extensive systems may not find it viable studied, though they are not yet operational.to adopt such measures. However, national plan- These include:ning strategies in large countries could poten- • reduction of hydrogen production by stimulat-tially bring about such changes. For example, ing acetogenic bacteria;as Eckard et al. (2000) suggest, concentrating • defaunation (eliminating certain protozoadairy production in the temperate zones of Aus- from the rumen); andtralia could potentially decrease methane emis- • vaccination (to reduce methanogens).120
    • Livestock’s role in climate change and air pollution These options would have the advantage of emissions by 21 percent relative to not coolingbeing applicable to free-ranging ruminants as (Sommer et al., 2004).well, although the latter option may encounter Additional measures include anaerobic diges-resistance from consumers (Monteny et al., tion (producing biogas as an extra benefit),2006). Defaunation has been proven to lead to a flaring/burning (chemical oxidation; burning),20 percent reduction in methane emissions on special biofilters (biological oxidation) (Mon-average (Hegarty, 1998), but regular dosing with teny et al., 2006; Melse and van der Werf, 2005),the defaunating agent remains a challenge. composting and aerobic treatment. Biogas is produced by controlled anaerobic digestion – the3.5.3 Mitigating CH4 emissions through bacterial fermentation of organic material underimproved manure management and biogas controlled conditions in a closed vessel. BiogasMethane emissions from anaerobic manure is typically made up of 65 percent methanemanagement can be readily reduced with exist- and 35 percent carbon dioxide. This gas caning technologies. Such emissions originate from be burned directly for heating or light, or inintensive mixed and industrial systems; these modified gas boilers to run internal combustioncommercially oriented holdings usually have the engines or generators.capacity to invest in such technologies. It is assumed that biogas can achieve a 50 per- The potential for emission abatement from cent reduction in emissions in cool climates formanure management is considerable and multi- manures which would otherwise be stored as liq-ple options exist. A first obvious option to consid- uid slurry (and hence have relatively high meth-er is balanced feeding, as it also influences other ane emissions). For warmer climates, whereemissions. Lower carbon to nitrogen ratios in methane emissions from liquid slurry manurefeed lead to increased methane emissions, in an storage systems are estimated to be over threeexponential fashion. Manure with high nitrogen times higher (IPCC, 1997), a reduction potentialcontent will emit greater levels of methane than of 75 percent is possible (Martinez, personalmanure with lower N contents. Hence increasing communication).the C to N ratio in feeds can reduce emissions. Various systems exist to exploit this huge The temperature at which manure is stored potential, such as covered lagoons, pits, tankscan significantly affect methane production. In and other liquid storage structures. These wouldfarming systems where manure is stored in the be suitable for large or small-scale biogas sys-stabling (e.g. in pig farms where effluents arestored in a pit in the cellar of a stable) emissionscan be higher than when manure is stored out-side at lower ambient temperatures. Frequentand complete removal of the manure from theindoor storage pits reduces methane emissionseffectively in temperate climates, but only wherethere is sufficient outdoor storage capacity (and © LEAD/Pierre Gerberadditional measures to prevent CH4 emissionsoutdoors). Reduction of gas production can alsobe achieved through deep cooling of manure (tobelow 10°C), though this requires higher invest-ment and also energy consumption with a riskof increased carbon dioxide emissions. Cooling Anaerobic digestor for biogas production in aof pig slurry can reduce in-house CH4 (and N2O) commercial pig farm – Central Thailand 2005 121
    • Livestock’s long shadowtems, with a wide range of technological options posting and often have a positive side-effect onand different degrees of sophistication. Addition- pathogen content.ally, covered lagoons and biogas systems producea slurry that can be applied to rice fields instead 3.5.4 Technical options for mitigating of untreated dung, leading to reduced methane N2O emissions and NH3 volatilizationemissions (Mendis and Openshaw, 2004). These The best way to manage the continuing humansystems are common practice in much of Asia, interference in the nitrogen cycle is to maxi-particularly in China. In Vietnam, Thailand and mize the efficiencies of human uses of N (Smil,the Philippines biogas is also widely used. A new 1999).opportunity in hot climate is the use of biogas Reducing the nitrogen content of manuresto fuel modern cooling systems (e.g. EVAP sys- as suggested above may also lead to lower N2Otem) and thereby achieve substantial savings on emissions from stables, during storage, andenergy costs. after application to soil. However, in most of these countries biogas An important mitigation pathway lies in raisinghas been helped to spread by subsidy schemes the low animal nitrogen assimilation efficiencyor other forms of promotion. Current uptake of (14 percent, against some 50 percent for cropsbiogas technologies is limited in many countries – see Sections 3.3.2 and 3.3.3) through morebecause of insufficient regulatory frameworks balanced feeding (i.e. by optimizing proteins orand absence of appropriate financial incen- amino acids to match the exact requirements oftives. The wider use of biogas systems (for use individual animals or animal groups). Improvedon-farm or for delivering electricity to the pub- feeding practices also include grouping animalslic net) depends on the relative price of other by gender and phase of production, and improv-energy sources. Usually biogas systems are not ing the feed conversion ratio by tailoring feedcompetitive in the absence of subsidies, other to physiological requirements. However, eventhan in remote locations where electricity and when good management practices are used toother forms of energy are unavailable or unre- minimize nitrogen excretion, large quantitiesliable. Biogas feasibility also depends on the still remain in the manure.degree to which there are options to co-digest Another possible intervention point is imme-waste products so as to increase gas production diately after reactive nitrogen is used as a(see Nielsen and Hjort-Gregersen, 2005). resource (e.g. digestion of feed), but before it The further development and promotion of is distributed to the environment. In intensivecontrolled anaerobic digestion will have sub- production, substantial N losses can occur dur-stantial additional positive effects related to ing storage primarily through volatilization ofother environmental problems caused by ani- ammonia. The use of an enclosed tank can near-mal wastes, and/or the promotion of renewable ly eliminate this loss. Maintaining a natural crustenergy sources. For example, anaerobic diges- on the manure surface in an open tank is almosttion offers benefits in terms of reduced odour as effective and more economical. However, theand pathogens. first option offers an important potential synergy Although more time consuming for the farm- with respect to mitigating methane emissions.er, possible solutions to reduce methane emis- N2O emissions from slurry applications tosions also lie in shifting towards solid manure grassland were reduced when slurry was storedmanagement. Aerobic treatments can also be for 6 months or passed through an anaero-used to reduce methane emissions and odour. bic digester prior to spreading (Amon et al.,In practice they are applied to liquid manures 2002). It can be inferred that during storage andthrough aeration and to solid manures by com- anaerobic digestion readily available C (which122
    • Livestock’s role in climate change and air pollutionwould otherwise fuel denitrification and increase phase is the use of nitrification inhibitors (NIs)gaseous N loss) is incorporated into microbial that can be added to urea or ammonium com-biomass or lost as CO2 or CH4. Hence there is pounds. Monteny et al. (2006) cite examples ofless available C in the slurry to fuel denitrifica- substantially reduced emissions. Some of thesetion when the slurry is applied to land. It follows substances can potentially be used on pasturesthat anaerobic digestion, e.g. for biogas produc- where they act upon urinary N, an approachtion, can substantially mitigate nitrous oxide and being adopted in New Zealand (Di and Cameron,methane emissions (provided the biogas is used 2003). Costs of NIs may be offset by increasedand not discharged). In addition, electricity can crop/pasture N uptake efficiency. The degree ofbe generated and N2O emissions from the spread adoption of NIs may depend on public percep-of (digested) slurry would also be reduced. tion of introducing yet another chemical into the The identification and choice of other N2O emis- environment (Monteny et al., 2006).sion mitigation options during storage are com- Options to reduce emissions from grazingplex, and the choice is also limited by farm and systems are particularly important as they con-environmental constraints and costs. Important stitute the bulk of nitrous oxide emissions. Fortrade-offs exist between methane and nitrous grazing animals, excessive losses from manureoxide emissions: technologies with potential to can be avoided by not overstocking pastures andreduce nitrous oxide emissions often increase avoiding late fall and winter grazing.those of methane and vice versa. A management Finally, land drainage is another option tochange from straw- to slurry-based systems for reduce nitrous oxide emissions before N entersexample may result in lower N2O emission, but the next phase of the nitrogen cascade. Improve-increased CH4 emission. Also, compaction of ment of soil physical conditions to reduce soilsolid manure heaps to reduce oxygen entering wetness in the more humid environments, andthe heap and maintaining anaerobic conditions especially in grassland systems, may signifi-has had mixed success in reducing N2O emis- cantly reduce N2O emissions. Soil compaction bysions (Monteny et al., 2006), and may increase traffic, tillage and grazing livestock can increaseCH4 emissions. the anaerobicity of the soil and enhance condi- Much of the challenge of reducing emissions tions for denitrification.of NH3 and N2O falls upon crop farmers. Rapid This section covered the technical options thatincorporation and shallow injection methods for have the largest mitigation potential and are ofmanure reduce N loss to the atmosphere by at global interest. Many other options could be pre-least 50 percent, while deep injection into the sented and their potential analyzed,18 but mostlysoil essentially eliminates this loss (Rotz, 2004) the latter would be far less significant and their(losses via leaching may increase though). Use of applicability to different systems and regionsa crop rotation that can efficiently recycle nutri- not as wide. Among the selection of options pre-ents, and applying N near the time it is needed by sented, those that contribute to the mitigationcrops reduces the potential for further losses. In of several gases at a time (anaerobic digestionmore generic terms, the key to reducing nitrous of manure), as well as those that provide otheroxide emissions is the fine-tuning of waste environmental benefits in parallel (e.g. pastureapplication to land with regard to environmental management) deserve special attention.conditions, including timing, amounts and formof application in response to crop physiology andclimate. 18 Mitigationoptions that more specifically focus on limiting Another technological option for reducing nitrate losses to water, though also relevant here, are pre-emissions during the application/deposition sented in the following chapter. 123
    • 04
    • Livestock’s role in water depletion and pollution4.1 Issues and trends such as power for hydroelectricity generationWater represents at least 50 percent of most and support of recreational activities to a highlyliving organisms and plays a key role in the diverse set of user groups. Freshwater resourc-functioning of the ecosystem. It is also a criti- es are the pillar sustaining development andcal natural resource mobilized by most human maintaining food security, livelihoods, indus-activities. trial growth, and environmental sustainability It is replenished through the natural water throughout the world (Turner et al., 2004).cycle. The evaporation process, mainly from the Nevertheless, freshwater resources areoceans, is the primary mechanism supporting scarce. Only 2.5 percent of all water resourcesthe surface-to-atmosphere portion of the cycle. are fresh water. The oceans account for 96.5 per-Evaporation returns to ocean and water bodies cent, brackish water for around 1 percent. Fur-as precipitation (US Geological Survey, 2005a; thermore, 70 percent of all freshwater resourcesXercavins and Valls, 1999). are locked up in glaciers, and permanent snow Freshwater resources provide a wide range of (polar caps for example) and the atmospheregoods such as drinking water, irrigation water, (Dompka, Krchnak and Thorne, 2002; UNES-or water for industrial purposes, and services CO, 2005). 110 000 km3 of freshwater fall on
    • Livestock’s long shadowearth in the form of precipitation annually, of 93 percent of water depletion worldwide (seewhich 70 000 km3 evaporate immediately into Table 4.1) (Turner et al., 2004). The irrigatedthe atmosphere. Out of the remaining 40 000 area has multiplied nearly five times over thekm3 only 12 500 km3 is accessible for human use last century and in 2003 amounted to 277 million(Postel, 1996). hectares (FAO, 2006b). Nevertheless, in recent Freshwater resources are unequally distrib- decades, growth in the use of water resourcesuted at the global level. More than 2.3 billion for domestic and industrial purposes has beenpeople in 21 countries live in water-stressed faster than for agriculture. Indeed, between 1950basins (having between 1 000 and 1 700 m3 per and 1995, withdrawals for domestic and industri-person per year). Some 1.7 billion people live al uses quadrupled, while they only doubled forin basins under scarcity conditions (with less agricultural purposes (Rosegrant, Cai and Cline,than 1 000 m3 per person per year) see Map 28, 2002). Today people consume 30–300 litres perAnnex 1 (Rosegrant, Cai and Cline, 2002; Kinje, person a day for domestic purposes, while 3 0002001; Bernstein, 2002; Brown, 2002). More than litres per day are needed to grow their daily foodone billion people do not have sufficient access (Turner et al., 2004).to clean water. Much of the world’s human popu- One of the major challenges in agriculturallation growth and agricultural expansion is tak- development today is to maintain food secu-ing place in water stressed regions. rity and alleviate poverty without further deplet- The availability of water has always been a ing water resources and damaging ecosystemslimiting factor to human activities, in particular (Rosegrant, Cai and Cline, 2002).agriculture, and the increasing level of demandfor water is a growing concern. Excessive with- The threat of increasing scarcitydrawals, and poor water management, have Projections suggest that the situation will worsenresulted in lowered groundwater tables, dam- in the next decades, possibly leading to increas-aged soils and reduced water quality worldwide. ing conflicts among usages and users. UnderAs a direct consequence of a lack of appropriate a “Business as usual scenario” (Rosegrant etwater resources management, a number of al., 2002), global water withdrawal is projectedcountries and regions are faced with ongoing to increase by 22 percent to 4 772 km3 in 2025.depletion of water resources (Rosegrant, Cai and This increase will be driven mainly by domestic,Cline, 2002). industrial and livestock uses; the latter show- Withdrawal of freshwater diverted from rivers ing a growth of more than 50 percent. Waterand pumped from aquifers has been estimated consumption for non-agricultural uses is pro-at 3 906 km3 for 1995 (Rosegrant, Cai and Cline, jected to increase by 62 percent between 19952002). Part of this water returns to the eco-system, though pollution of water resourcesis accelerated by the increasing discharge of Table 4.1wastewater into water courses. Indeed, in devel- Water use and depletion by sectoroping countries, 90–95 percent of public waste- Sector Water use Water depletionwater and 70 percent of industrial wastes are (.......... Percentages of total ..........)discharged into surface water without treatment(Bernstein, 2002). Agriculture 70 93 The agricultural sector is the largest user Domestic 10 3of freshwater resources. In 2000, agriculture Industrial 20 4accounted for 70 percent of water use and Source: Brown (2002); FAO-AQUASTAT (2004).126
    • Livestock’s role in water depletion and pollutionand 2025. The use of irrigation water, however, of adequate stream flows, especially during drywill rise by only 4 percent over that period. The seasons. Improper land use can severely con-highest increase in demand for irrigation water strain future access to water resources and mayis expected for sub-Saharan Africa and Latin threaten the proper functioning of ecosystems.America with 27 and 21 percent, respectively; Water cycles are further affected by deforesta-both regions have only limited use of irrigation tion, an ongoing process at the pace of 9.4 mil-today (Rosegrant, Cai and Cline, 2002). lion hectares per year according to FAO’s latest As a direct consequence of the expected assessment (FAO, 2005a).increase in demand for water, Rosegrant, Cai Water also plays a key role in ecosystemand Cline (2002) projected that by 2025, 64 per- functioning, acting as a medium and/or reactantcent of the world’s population will live in water- of biochemical processes. Depletion will affectstressed basins (against 38 percent today). A ecosystems by reducing water availability torecent International Water Management Insti- plant and animal species, inducing a shift towardtute (IWMI) assessment projects that by 2023, dryer ecosystems. Pollution will also harm eco-33 percent of the world’s population (1.8 billion systems, as water is a vehicle for numerouspeople) will live in areas of absolute water scar- pollution agents. As a result, pollutants have ancity including Pakistan, South Africa, and large impact not only locally but on various ecosys-parts of India and China (IWMI, 2000). tems along the water cycle, sometimes far from Increasing water scarcity is likely to compro- the initial sources.mise food production, as water will have to be Among the various ecosystems affected bydiverted from agricultural use to environmental, trends in water depletion, wetlands ecosystemsindustrial and domestic purposes (IWMI, 2000). are especially at risk. Wetlands ecosystems areUnder the “business as usual scenario” men- the most species-diverse habitats on earth andtioned above, water scarcity may cause a loss include lakes, floodplains, marshes and deltas.of potential production of 350 million tonnes of Ecosystems provide a wide range of environmen-food, almost equal to the current total United tal services and goods, valued globally at US$33States grain crop production (364 million tonnes trillion of which US$14.9 trillion are provided byin 2005) (Rosegrant, Cai and Cline, 2002; FAO, wetlands (Ramsar, 2005). These include flood2006b). The countries under absolute water control, groundwater replenishment, shorelinescarcity will have to import a substantial propor- stabilization and storm protection, sediment andtion of their cereal consumption, while those nutrient regulation, climate change mitigation,unable to finance these imports will be threat- water purification, biodiversity conservation,ened by famine and malnutrition (IWMI, 2000). recreation, tourism and cultural opportunities. Even countries with sufficient water resources Nevertheless, wetlands ecosystems are underwill have to expand their water supplies to make great threat and are suffering from over-extrac-up for the increasing demand. There is wide- tion, pollution and diversion of water resources.spread concern that many countries, especially An estimated 50 percent of world wetlands havein sub-Saharan Africa, will not have the required disappeared over the last century (IUCN, 2005;financial and technical capacity (IWMI, 2000). Ramsar, 2005). Water resources are threatened in other ways. The impacts of the livestock sector on waterInappropriate land use can reduce water sup- resources are often not well understood byplies by reducing infiltration, increasing run- decision-makers. The primary focus is usu-off and limiting the natural replenishment of ally the most obvious segment of the livestockgroundwater resources and the maintenance commodity chain: production at farm level. But 127
    • Livestock’s long shadowthe overall water use1 directly or indirectly bythe livestock sector is often ignored. Similarly,the contribution of the livestock sector to waterdepletion2 focuses mainly on water contamina-tion by manure and waste. This chapter attempts to provide a compre- © FAO/9286/H.D. Namhensive overview of the livestock sector’s role inthe water resources depletion issue. More spe-cifically, we will provide quantitative estimates ofwater use and pollution associated with the mainsegments of the animal food commodity chain. A worker gives water to pigs raised near chicken cage We will successively also analyse livestock’s on farm at Long An province – Viet Nam 2005contribution to the water pollution and evapo-transpiration phenomenon and its impact on the sents 60 to 70 percent of the body weight and iswater resource replenishment process through essential for animals in maintaining their vitalimproper land use. The final section proposes physiological functions. Livestock meet theirtechnical options for reversing these trends of water requirements through drinking water, thewater depletion. water contained in feedstuffs and metabolic water produced by oxidation of nutrients. Water4.2 Water use is lost from the body through respiration (lungs),Livestock’s use of water and contribution to evaporation (skin), defecation (intestines) andwater depletion trends are high and growing. An urination (kidneys). Water losses increase withincreasing amount of water is needed to meet high temperature and low humidity (Pallas,growing water requirements in the livestock 1986; National Research Council, 1994, Nationalproduction process, from feed production to Research Council, 1981). Reduction of waterproduct supply. intake results in lower meat, milk and egg pro- duction. Deprivation of water quickly results in4.2.1 Drinking and servicing a loss of appetite and weight loss, with deathWater-use for drinking and servicing animals is occurring after a few days when the animal hasthe most obvious demand for water resources lost between 15 to 30 percent of its weight.related to livestock production. Water repre- In extensive grazing systems, the water con- tained in forages contributes significantly to1 meeting water requirements. In dry climates, “Water use” (also referred as “water withdrawals” in the literature) refers to the water removed from a source and the water content of forages decreases from 90 used for human needs, some of which may be returned to percent during the growing season to about 10 to the original source and reused downstream with changes in 15 percent during the dry season (Pallas, 1986). water quantity and quality. The “water demand”, refers to a potential water use (adapted from Gleick, 2000). Air-dried feed, grains and concentrate usually2 “Water depletion” (also referred as “water consumption” distributed within industrialized production sys- in the literature) refers to the use or removal of water from tems contain far less water: around 5 to 12 per- a water basin that renders it unavailable for other uses. It cent of feed weight (National Research Council, includes four generic processes: evapo-transpiration; flows to sinks; pollution; and incorporation within agricultural or 2000, 1981). Metabolic water can provide up to 15 industrial products (adapted from Roost et al., 2003, Gleick, percent of water requirements. 2000). We deliberately chose to single out pollution in the A wide range of interrelated factors influence title of this chapter, although it’s covered by the notion of depletion, in order to highlight the importance of this mecha- water needs, including: the animal species; the nism to the reader. physiological condition of the animal; the level of128
    • Livestock’s role in water depletion and pollutionTable 4.2Drinking water requirements for livestockSpecies Physiological condition Average Air temperature °C Weight 15 25 35 Water requirements (kg) (.......... litres/animal/day ..........)Cattle African pastoral system-lactating – 2 litres milk/day 200 21.8 25 28.7 Large breed – Dry cows – 279 days pregnancy 680 44.1 73.2 102.3 Large breed – Mid-lactation – 35 litres milk/day 680 102.8 114.8 126.8Goat Lactating – 0.2 litres milk/day 27 7.6 9.6 11.9Sheep Lactating – 0.4 litres milk/day 36 8.7 12.9 20.1Camel Mid-lactation – 4.5 litres milk/day 350 31.5 41.8 52.2Chicken Adult broilers (100 animals) 17.7 33.1 62 Laying eggs (100 animals) 13.2 25.8 50.5Swine Lactating – daily weight gain of pigs 200g 175 17.2 28.3 46.7Sources: Luke (2003); National Research Council (1985; 1987; 1994; 1998; 2000); Pallas (1986); Ranjhan (1998).dry matter intake; the physical form of the diet; Production systems usually differ in theirwater availability and quality; temperature of the water use per animal and in how these require-water offered; the ambient temperature and the ments are met. In extensive systems, the effortproduction system (National Research Council, expended by animals in search of feed and water1981; Luke, 1987). Water requirements per ani- increases the need for water considerably, com-mal can be high, especially for highly productive pared to industrialized systems where animalsanimals under warm and dry conditions (see do not move around much. By contrast, intensiveTable 4.2). production has additional service water require- Livestock production, especially in industri- ments for cooling and cleaning facilities. It is alsoalized farms, also requires service water – to important to notice that water sourcing differsclean production units, to wash animals, for widely between industrialized and extensive pro-cooling the facilities, the animals and their duction systems. In extensive livestock systems,products (milk) and for waste disposal (Hutson 25 percent of the water requirements (includinget al., 2004; Chapagain and Hoekstra, 2003). In water services) come from feed, against only 10particular, pigs require a lot of water when kept percent in intensive livestock production sys-in “flushing systems 3”;in this case service water tems (National Research Council, 1981).requirements can be seven times higher than In some places the importance of livestockdrinking water needs. While data are scarce, water use for drinking and servicing comparedTable 4.3 gives some indication of these water to other sectors can be striking. For example inrequirements. The estimates do not take into Botswana water use by livestock accounts for 23account the cooling requirements, which can be percent of the total water use in the country andsignificant. is the second principal user of water resources. As groundwater resources replenish only slowly, the water table in the Kalahari has substantially3 decreased since the nineteenth century. Other In a flushing system, a large volume of water carries manure down a gutter, usually sloped toward storage, such as an sectors will pose additional water demands in earthen lagoon or basin (Field et al., 2001). future; and water scarcity may become dramatic 129
    • Livestock’s long shadowTable 4.3 Globally, the water requirements for livestockService water requirements for different livestock drinking and servicing represent only 0.6 percenttypes of all freshwater use (see Tables 4.4 and 4.5). Service water This direct use figure is the only one that most (litres/animal/day) decision-makers take into consideration. As aAnimal Age group Industrial Grazing result, the livestock sector is not usually consid-Beef cattle Young calves 2 0 ered one of the principal drivers for the depletion Adult 11 5 of freshwater resources. However, this figure isDairy cattle Calves 0 0 a considerable underestimate, as it does not take Heifers 11 4 Milking cows 22 5 into account other water requirements the live-Swine Piglet 5 0 stock sector entails both directly and indirectly. Adult 50 25 We will now examine the water implications of Lactating 125 25 the entire production process.Sheep Lamb 2 0 Adult 5 5Goats Kid 0 0 4.2.2 Product processing Adult 5 5 The livestock sector provides a wide range ofBroiler chicken Chick*100 1 1 commodities, from milk and meat to high value- Adult*100 9 9 added products such as leather or pre-cookedLaying hens Chick*100 1 1 Laying eggs*100 15 15 dishes. Going through the whole chain and iden-Horses Foal 0 5 tifying the share of the water use imputable to Mature horses 5 5 the livestock sector is a complex exercise. WeSource: Chapagain and Hoekstra (2003). focus here on the primary steps of the product processing chain, which includes slaughtering, meat and milk processing and tanning activi-(see Box 4.1; Els and Rowntree, 2003; Thomas, ties.2002). However in most countries water usefor drinking and servicing remains small com- Slaughterhouses and the agro-food industrypared to other sectors. In the United States for Primary animal products such as live animalsexample, although locally important in some or milk, are usually processed into differentstates, livestock drinking and service water use meat and dairy products before consumption.was less than 1 percent of total freshwater use Processing of meat includes a range of activi-in 2000 (Hutson et al., 2004). ties, from slaughtering to complex value-adding Based on metabolic requirements, estimates activities. Figure 4.1 depicts the generic processconcerning the extent of production systems and for meat, although the steps can vary dependingtheir water use, we can estimate global water on species. In addition to these generic pro-use to meet livestock drinking requirements at cesses, meat processing operations may also16.2 km3, and service water requirements at 6.5 incorporate offal processing and rendering. Ren-km3 (not including service water requirements dering converts by-products into value-addedfor small ruminants) (see Table 4.4 and 4.5). At products such as tallow, meat and blood meals.the regional level the highest demand for servic- Like many other food processing activities,ing and drinking water is seen in South America hygiene and quality requirements in meat pro-(totalling 5.3 km3/yr), South Asia (4.1 km3/yr) and cessing result in high water usage and conse-sub-Saharan Africa (3.1 km3/yr). These areas quently high wastewater generation. Water is arepresent 55 percent of global water require- major input at each processing step, except forments of the livestock sector. final packaging and storage (see Figure 4.1).130
    • Livestock’s role in water depletion and pollution Box 4.1 Livestock water use in Botswana Predominantly a dryland country, Botswana is Many ranches in the Kalahari have installed already experiencing ‘water stress’ – that is, more boreholes than permitted in order to provide freshwater availability ranges between 1 000 and water to the increasing number of grazing ani- 1 700m3 per person per year. Livestock are a mals. The increased use of boreholes has caused major user of freshwater resources in Botswana. groundwater levels to decrease, and has prob- In 1997, livestock accounted for 23 percent of the ably diminished flows in natural permanent water total water use of the country and was the second features. As a direct consequence, the water table principal user of water resources (irrigation and in the Kalahari has fallen substantially since the forestry only represent 15 percent of the demand). nineteenth century. Groundwater resources account for 65 percent Under current rates of abstraction, the lifetime of the total water available in Botswana, but they of surface and groundwater resources in Botswana are limited. The recharge of aquifers ranges from is limited to a few decades. As water use by over 40 mm/yr in the extreme north to virtually households is predicted to increase rapidly from zero in the central and western parts of the coun- approximately 29 percent (1990) to approximately try. The rechargeable volume of groundwater for 52 percent of total demand in 2020. The pressure Botswana is less than 0.4 percent of Botswana’s on water resources will increase and present total renewable resources. levels of livestock production may no longer be Groundwater is supplied through boreholes for sustained. domestic and livestock uses. It is estimated that there are 15 000 boreholes scattered throughout Botswana. In 1990, total water abstraction from boreholes was 76 million m3, which was 760 per- cent more than the recharge rate. Sources: Els and Rowntree (2003); Thomas (2002).Table 4.4Water use for drinking-water requirementsRegions Total yearly water intake (km3) Cattle Buffaloes Goats Sheep Pigs Poultry (100) TotalNorth America 1.077 0.000 0.002 0.006 0.127 0.136 1.350Latin America 3.524 0.014 0.037 0.077 0.124 0.184 3.960Western Europe 0.903 0.002 0.013 0.087 0.174 0.055 1.230Eastern Europe 0.182 0.000 0.003 0.028 0.055 0.013 0.280Commonwealth of Independent States 0.589 0.003 0.009 0.036 0.040 0.029 0.710West Asia and North Africa 0.732 0.073 0.140 0.365 0.000 0.118 1.430Sub-Saharan Africa 1.760 0.000 0.251 0.281 0.035 0.104 2.430South Asia 1.836 1.165 0.279 0.102 0.017 0.096 3.490East and Southeast Asia 0.404 0.106 0.037 0.023 0.112 0.180 0.860Oceania 0.390 0.000 0.001 0.107 0.010 0.009 0.520Total 11.400 1.360 0.770 1.110 0.690 0.930 16.260Sources: FAO (2006b); Luke(2003); National Research Council (1985; 1987; 1994; 1998; 2000a); Pallas (1986); Ranjhan (1998). 131
    • Livestock’s long shadowTable 4.5Water use for service water requirementsRegion Service water (km3) Cattle Pigs Poultry (100) TotalNorth America 0.202 0.682 0.008 0.892Latin America 0.695 0.647 0.009 1.351Western Europe 0.149 1.139 0.004 1.292Eastern Europe 0.028 0.365 0.001 0.394Commonwealth of Independent States 0.101 0.255 0.002 0.359West Asia and North Africa 0.145 0.005 0.006 0.156Sub-Saharan Africa 0.415 0.208 0.003 0.626South Asia 0.445 0.139 0.003 0.586East and Southeast Asia 0.083 0.673 0.009 0.765Oceania 0.070 0.051 0.000 0.121Total 2.333 4.163 0.046 6.542Note: Calculation based on Chapagain and Hoekstra (2003). At red meat (beef and buffalo) abattoirs, water of water. Best practice water use in commercialis used primarily for washing carcasses at vari- milk processes is reported to be 0.8 to 1 litreous stages and for cleaning. Of total water use water/kg of milk (UNEP, 1997a). These con-for processing, between 44 and 60 percent is servative estimates result in a global water useconsumed in the slaughter, evisceration and for milk processing over 0.6 km3 (0.015 percentboning areas (MRC, 1995). Water usage rates of the global water use), not considering waterrange from 6 to 15 litres per kilo of carcass. used for derived products, especially cheese.Given that the world production of beef andbuffalo meat was 63 million tonnes in 2005 a Tanneriesconservative estimate of the water use for these Between 1994 and 1996 approximately 5.5 mil-stages would lie between 0.4 and 0.95 km3, i.e. lion tonnes of raw hides were processed eachbetween 0.010 percent and 0.024 percent of year to produce 0.46 million tonnes of heavyglobal water use (FAO, 2005f). leather and about 940 million m2 of light leather. In poultry processing plants, water is used to A further 0.62 million tonnes of raw skins on awash carcasses and cleaning; hot water scalding dry basis were converted into almost 385 millionof birds prior to defeathering; in water flumes m2 of sheep and goat leather.for transporting feathers, heads, feet and vis- The tanning process includes four main opera-cera and for chilling birds. Poultry processing tional steps: storage and beam house; tan-tends to be more water-intensive per weight unit yard; post tanning; and finishing. Dependingthan red meat processing (Wardrop Engineering, on the type of technology applied, the water1998). Water use is in the range 1 5­90 litres per requirements for processing skins vary greatly,bird processed (Hrudey, 1984). In 2005, a total from 37 to 59 m3 per tonne of raw hides whenof 48 billion birds were slaughtered globally. A using conventional technologies to 14 m3 whenconservative estimate of global water use would using advanced technologies (see Table 4.6). Thisbe around 1.9 km3, representing 0.05 percent of amounts to a world total of 0.2 to 0.3 km3 perthe water use. year (0.008 percent of global water use). Dairy products also require significant amounts The water use requirements for processing132
    • Livestock’s role in water depletion and pollution Figure 4.1 Flow diagram for meat Table 4.6 processing operations Water use and depletion in tanning operations Discharge (m3/tonne raw hide) Major input Process step Major waste streams Operation Conventional Advanced technology technology Water Delivery and holding Manure mortalities Soaking 7–9 2 of livestock Liming 9–15 4.5 Water Stunning and Blood Deliming, bating 7–11 2 slaughter wastewater Tanning 3–5 0.5 Hides, feathers, hooves, Post-Tanning 7–13 3 Water Hide removal heads, etc. dehairing/defeathering wastewater Finishing 1–3 0 Total 34–56 12 Water Offal/Viscera Evisceration paunch manure Source: Gate information services – GTZ (2002) wastewater Water Trimming and Fat and meat trimmines carcass washing wastewater resources. When water, evapotranspired by feed cropland, is attributed to the production of live- Water Boning Wastewater stock, the amounts involved are so large that the other water uses described above pale by Water Chilling Wastewater comparison. Zimmer and Renault (2003) for example show in a rough accounting effort that Packaging materials the livestock sector may account for some 45 Packaging percent of the global budget of water used in food production. However, a large share of this Cold storage water use is not environmentally significant. Evapotranspiration by grasslands and non-cul- tivated fodder land used for grazing represents Source: UNEP (2004a). a large share. This water generally has little to no opportunity cost, and indeed the amount of water lost in the absence of grazing might notanimal products can have a significant environ-mental impact in some locations. However, themain environmental threat lies in the volume of © Photo courtesy of USDA NRCS/Charma Comerpollutants discharged locally by the processingunits.4.2.3 Feed productionAs previously described, the livestock sector isthe world’s largest anthropogenic land user. Thevast majority of this land, and much of the waterit contains and receives are destined for feedproduction. Evapotranspiration is the main mechanism Handline sprinkler irrigation system –by which crop and grassland deplete water United States 2000 133
    • Livestock’s long shadowbe any lower. More intensively managed grazing the sector may, more indirectly, lead to deple-lands often have agricultural potential, but are tion of available water because it reduces themostly located in water abundant areas, i.e. here water available for other uses, particularly foodit is more the land that has the opportunity cost crops.rather than water. In view of the increase of “costly” water use Water used for feed production in extensive by the livestock sector, it is important to assessland-based livestock production systems is not its current significance. Annex 3.4 presents aexpected to substantially increase. As stated pre- methodology for quantifying this type of livestockviously, grazing systems are in relative decline in water use and assessing its significance. Thismost parts of the world. One important reason is assessment is based on spatially detailed water-that most grazing is in arid or semi-arid zones balance calculations and information availablewhere water is scarce, limiting the expansion for the four most important feedcrops: barley,or intensification of livestock production. Pro- maize, wheat and soybean (hereafter referred toduction from mixed systems is still expanding as BMWS). The results presented in Table 4.7,rapidly, and water is not a limiting factor in most therefore, do not represent the entire feed cropsituations. Here, productivity gains are expected water use. These four crops account for roughlyfrom an increased level of integration between three-quarters of the total feed used in thelivestock and crop production, with animals con- intensive production of monogastrics. For othersuming considerable amounts of crop residues. significant users of these external inputs, i.e. the In contrast, more intensively managed mixed intensive dairy sector, this share is in the samesystems and industrial livestock systems are order of magnitude.characterized by a high level of external inputs, Annex 3.4 describes two different approachesi.e. concentrate feed and additives, often trans- that are designed to deal with uncertainty inported over long distances. The demand for estimating water use by feed crops, related tothese products, and thereby demand for the lack of knowledge of the locations of feed-dedi-corresponding raw materials (i.e. cereal and oil cated cropping. As Table 4.7 shows, these twocrops), is increasing rapidly4. In addition, cerealand oil crops occupy arable land, where watergenerally has a considerable opportunity cost. 5 FAO (2003a) estimates that about 80 percent of the projectedSubstantial amounts are produced by irrigation growth in crop production in developing countries will comein relatively water short areas5. In such areas from intensification in the form of yield increases (67 per-the livestock sector may be directly responsible cent) and higher cropping intensities (12 percent). The share due to intensification will go up to 90 percent and higher infor severe environmental degradation through the land-scarce regions of the West Asia/North Africa andwater depletion, depending on the source of the South Asia. It is estimated that in the developing countries atirrigation water. Although, in rainfed areas, even present, irrigated agriculture, with about a fifth of all arablethe increasing appropriation of arable land by land, accounts for 40 percent of all crop production and almost 60 percent of cereal production. The area equipped for irrigation in developing countries is projected to expand by 40 million hectares (20 percent) over the projection period.4 An increasing share of the increment in the production of This underlines the importance of the livestock sector’s cereals, mainly coarse grains, will be used in livestock feed. responsibility for irrigation water use: feed production may As a result, maize production in the developing countries intensify in many locations, but particularly production hot is projected to grow at 2.2 percent p.a. against «only» 1.3 spots like central China, the mid west of the United States, percent for wheat and 1.0 percent for rice (FAO, 2003a). Such and the Latin American area covered by Eastern Paraguay, contrasts are particularly marked in China where wheat and Southern Brazil and Northern Argentina may develop into rice production is expected to grow only marginally over the increasingly important global centres of supply that will both projection period of aforementioned report, while maize pro- expand and intensify, which may turn currently sufficient duction is expected to nearly double. water supply levels into a limiting production factor.134
    • Livestock’s role in water depletion and pollutionapproaches yield very similar results. This sug- Asia (ESEA), in both cases also representing agests that despite a certain number of unverified high share of the total (about 15 percent). A con-assumptions, the resulting aggregate quantities siderable portion of the irrigation water in themay provide fairly accurate estimates. United States originates from fossil groundwater Globally, BMWS feed accounts for some 9 per- resources (US Geological Survey, 2005). In ESEA,cent of all irrigation water evapotranspired glob- in view of the changes under way in the livestockally. When we include evapotranspiration of sector, water depletion and conflicts over its usewater received from precipitation in irrigated may become serious problems over the comingareas, this share rises to some 10 percent of decades.total water evapotranspired in irrigated areas. Despite its environmental relevance, irriga-Considering that BMWS unprocessed feed mate- tion water represents only a small part of totalrial represents only some three-quarters of the BMWS feed water evapotranspired (6 percentfeed given to intensively managed livestock, globally). With respect to other crops, BMWSnearly 15 percent of water evapotranspired in feed in North and Latin America is preferen-irrigated areas can probably be attributed to tially located in rainfed areas: its share in rainfedlivestock. evapotranspiration is much larger than that in There are pronounced regional differences. the evapotranspiration of irrigation water. InIn sub-Saharan Africa and in Oceania, very little Europe on the contrary BMWS feed is preferen-irrigation is dedicated to BMWS feed, either in tially irrigated, while even in a critically water-absolute or in relative terms. In South Asia/India, short region such as WANA, the BMWS feedthe amount of irrigation water evapotranspired by share of evapotranspiration from irrigated landBMWS feed, although considerable, represents exceeds that of rainfed arable land. It is clearonly a small share of total water evapotranspired that feed production consumes large amountsthrough irrigation. Similar absolute amounts in of critically important water resources and com-the more water short West Asia and North Africa petes with other usages and users.region represent some 15 percent of total waterevapotranspired in irrigated areas. By far the 4.3 Water pollutionhighest share of water evapotranspired through Most of the water used by livestock returns toirrigation is found in Western Europe (over 25 the environment. Part of it may be re-usable inpercent), followed by eastern Europe (some 20 the same basin, while another may be polluted6percent). Irrigation is not very widespread in or evapotranspired and, thereby, depleted. WaterEurope, which is generally not short of water, polluted by livestock production, feed productionand indeed the corresponding BMWS feed irriga- and product processing detracts from the watertion water use is less in absolute terms than for supply and adds to depletion.WANA. But the southern part of Western Europe Pollution mechanisms can be separated intoregularly suffers summer droughts. In south- point source and non–point source. Point-sourcewestern France for example irrigated maize (for pollution is an observable, specific and con-feed) has repeatedly been held responsible for fined discharge of pollutants into a water body.severe drops in the flow of major rivers, as well Applied to livestock production systems, point-as damage to coastal aquaculture during suchsummer droughts, and unproductive pasturesfor the ruminant sector (Le Monde, 31-07-05). 6 Water pollution is an alteration of the water quality by wasteThe highest absolute quantities of BMWS feed to a degree that affects its potential use and results inirrigation water evapotranspired are found in modified physico-chemical and microbiological propertiesthe United States and in East and Southeast (Melvin, 1995). 135
    • Livestock’s long shadowTable 4.7Evapotranspiration of water for production of barley, maize, wheat and soybeanbean (BMWS) for feed Irrigated BMWS feed Rainfed BMWS feed BMWS feedRegion/Country Evapotranspired Percentage Percentage Water Percentage irrigation irrigation of total of total evapotranspired of total water ET as water irrigation water km3 water percentage km3 water evapotranspired evapotranspired of total evapotranspired in irrigated in rainfed BMWS feed areas1 cropland water ETNorth America 14.1 – 20.0 9 – 13 11 – 15 321 – 336 21 – 22 4–6Latin America and the Caribbean 3.0 – 3.8 6 – 8 7 – 9 220 – 282 12 – 15 1Western Europe 8.5 – 9.5 25 – 28 25 – 29 65 – 99 14 – 22 7 – 10Eastern Europe 1.8 – 2.4 17 – 22 19 – 23 30 – 46 12 – 18 4–5Commonwealth of Independent States 2.3 – 6.0 3 – 7 3 – 7 19 – 77 2 – 8 7–9West Asia and North Africa 11.2 – 13.1 9 – 10 13 – 14 30 – 36 9 – 11 17 – 19Sub-Saharan Africa 0.2 1 1 20 – 27 1 – 2 1South Asia 9.1 – 11.7 2 – 3 2 – 3 36 – 39 3 16 – 18East and Southeast Asia 20.3 – 30.1 14 – 20 13 – 18 226 – 332 11 – 16 6–7Oceania 0.3 – 0.6 3 – 5 3 – 5 1.7 – 12 1 – 4 5 – 12Australia 0.3 – 0.6 3 – 5 4 – 6 1.4 – 11 1 – 5 5 – 14China 15.3 – 19.3 14 – 18 15 – 16 141 – 166 14 – 16 7–8India 7.3 – 10.0 3 2 – 3 30 – 36 3 17 – 18Brazil 0.2 – 0.4 6 – 10 9 – 14 123 – 148 14 – 16 0World 81 – 87 8 – 9 10 1 103 – 1 150 10 – 11 6Note: Figures in bold represent results of the Spatial Concentration approach. Other figures are based on the area wide integrationapproach (see Annex 3.4 for details on the methodology). All figures are actual evapotranspiration (ET) estimates, based on totalirrigation and natural ET data provided by J. Hoogeveen, FAO (estimated according to the methodology described in FAO, 2003a).1 Evapotranspiration from irrigated areas is the sum of evapotranspiration from irrigation water and evapotranspiration fromprecipitation in irrigated areas.Source: Own calculations.source pollution refers to feedlots, food process- can pose serious threats to the environmenting plants, and agrichemical processing plants. (Gerber and Menzi, 2005). Different mechanismsNon-point source pollution is characterized by can be involved in the contamination of freshwa-a diffuse discharge of pollutants, generally over ter resources by manure and wastewater. Waterlarge areas such as pastures. contamination can be direct through the loss via runoff from farm buildings, losses from failure4.3.1 Livestock waste of storage facilities, deposition of faecal materialMost of the water used for livestock drinking into freshwater sources and deep percolationand servicing returns to the environment in and transport through soil layers via drainagethe form of manure and wastewater. Livestock waters at farm level. It can also be indirectexcreta contain a considerable amount of nutri- through non-point source pollution from surfaceents (nitrogen, phosphorous, potassium), drug runoff and overland flow from grazing areas andresidues, heavy metals and pathogens. If these croplands.get into the water or accumulate in the soil, they136
    • Livestock’s role in water depletion and pollutionTable 4.8Nutrient intake and excretions by different animalsAnimal Intake Retention Excretion Percentage (kg/year) (kg/year) (kg/year) of N excreted in mineral N P N P N P form1Dairy cow2 163.7 22.6 34.1 5.9 129.6 16.7 69Dairy cow3 39.1 6.7 3.2 0.6 35.8 6.1 50Sow2 46.0 11.0 14.0 3.0 32.0 8.0 73Sow3 18.3 5.4 3.2 0.7 15.1 4.7 64Growing pig2 20.0 3.9 6.0 1.3 14.0 2.5 78Growing pig3 9.8 2.9 2.7 0.6 7.1 2.3 59Layer hen2 1.2 0.3 0.4 0.0 0.9 0.2 82Layer hen3 0.6 0.2 0.1 0.0 0.5 0.1 70Broiler2 1.1 0.2 0.5 0.1 0.6 0.1 83Broiler3 0.4 0.1 0.1 0.0 0.3 0.1 601 Assumed equivalent to urine N excretion. As mineral N is susceptible to volatilization, this percentage is often lower in manure applied on the land.2 Highly productive situations3 Less productive situations.Note: Owing to the variation in intake and nutrient content of the feeds, these values represent examples, not averages, for highlyand less productive situations.Source: de Wit et al., (1997).The main pollutants (16.5), poultry broilers (16.9), sheep (10.3), beefNutrient surpluses stimulate eutrophication and (9.6) and dairy cattle (6.7) (Sharpley et al., 1998may represent a health hazard in Miller, 2001). In intensive production areas,Nutrient intake by animals can be extremely high these figures result in high nutrient surpluses(see Table 4.8). For example a productive dairy that can overwhelm the absorption capacitiescow ingests up to 163.7 kg of N and 22.6 kg of of local ecosystems and degrade surface andP per year. Some of the nutrients ingested are groundwater quality (Hooda et al., 2000).sequestered in the animal, but most of it return According to our assessment, at the globalto the environment and may represent a threat level, livestock excreta in 2004 were estimatedto water quality. Annual nutrient excretions by to contain 135 million tonnes of N and 58 mil-different animals are presented in Table 4.8. In lion tonnes of P. In 2004, cattle were the largestthe case of a productive dairy cow 129.6 kg of contributors for the excretion of nutrients withN (79 percent of the total ingested) and 16.7 kg 58 percent of N; pigs accounted for 12 percentof P (73 percent) is excreted every year (de Wit and poultry for 7 percent.et al., 1997). The phosphorus load excreted by The major contributors of nutrients are theone cow is equivalent to that of 18–20 humans mixed production systems that represent 70.5(Novotny et al., 1989). Nitrogen concentration is percent of N and P excretion, followed by grazinghighest in hog manure (76.2 g/N/kg dry weight), systems with 22.5 percent of the annual N and Pfollowed by turkeys (59.6 g/kg), poultry layers excretion. Geographically the biggest single con-(49.0), sheep (44.4), poultry broilers (40.0), dairy tributor is Asia, which represents 35.5 percent ofcattle (39.6) and beef cattle (32.5). Phosphorus the global annual excretion of N and P.content is highest in poultry layers (20.8 g/P/kg High concentrations of nutrients in waterdry weight), followed by hogs (17.6), turkeys resources can lead to over-stimulation of aquatic 137
    • Livestock’s long shadowplant and algae growth leading to eutrophication, Phosphorus is often considered as the keyundesirable water flavour and odour, and exces- limiting nutrient in most aquatic ecosystems.sive bacterial growth in distribution systems. In proper functioning ecosystems the ability ofThey can protect micro-organisms from the wetlands and streams to retain P is then crucialeffect of salinity and temperature, and may pose for downstream water quality. But an increasinga public health hazard. Eutrophication is a natu- number of studies have identified N as the keyral process in the ageing of lakes and some estu- limiting nutrient. In general terms, P tends toaries, but livestock and other agriculture-related be more of a problem with surface water qual-activities can greatly accelerate eutrophication ity, whereas N tends to pose more of a threat toby increasing the rate at which nutrients and groundwater quality by nitrate leaching throughorganic substances enter aquatic ecosystems soil layers (Mosley et al., 1997; Melvin, 1995;from their surrounding watersheds (Carney et Reddy et al., 1999; Miller, 2001; Carney, Cartyal., 1975; Nelson et al., 1996). Globally, the depo- and Colwell, 1975; Nelson, Cotsaris and Oades,sition of nutrients (especially N) exceeds the 1996).critical loads for eutrophication for 7–18 percentof the area of natural and semi-natural ecosys- Nitrogen: Nitrogen is present in the environmenttems (Bouwman and van Vuuren, 1999). in different forms. Some forms are harmless, If the plant growth resulting from eutrophica- while others are extremely harmful. Dependingtion is moderate, it may provide a food base for on its form, N can be stored and immobilizedthe aquatic community. If it is excessive, algal within the soil, or it can leach to groundwaterblooms and microbial activity may overuse dis- resources, or it can be volatized. Inorganic N issolved oxygen resources, which can damage the very mobile through the soil layers compared toproper functioning of ecosystems. Other adverse organic N.effects of eutrophication include: Nitrogen is excreted by livestock both in• shifts in habitat characteristics owing to organic and inorganic compounds. The inorganic change in the mix of aquatic plants; fraction is equivalent to the N emitted in urine• replacement of desirable fish by less desir- and is usually greater than the organic one. able species, and the associated economic Direct losses of N from excreta and manure take losses; four main forms: ammonia (NH3), dinitrogen• production of toxins by certain algae; (N2), nitrous oxide (N2O) or nitrate (N03-) (Mil-• increased operating expenses of public water chunas and Lauenroth, 1993; Whitmore, 2000). supplies; Part of the inorganic N is volatized and emitted• infilling and clogging of irrigation canals with as ammonia in animal houses, during deposition aquatic weeds; and manure storage, after manure application• loss of recreational use opportunities; and and on pastures.• impediments to navigation due to dense weed Storage and application conditions of manure growth. greatly influence the biological transformation of These impacts occur both in freshwater the N compounds, and the resulting compoundsand marine ecosytems, where algal blooms pose different threats to the environment. Underare reported to cause widespread problems anaerobic conditions, nitrate is transformed intoby releasing toxins and causing anoxia (“dead harmless N2 (denitrification). However, if organiczones”), with severe negative impacts on aqua- carbon is deficient, relative to nitrate, the pro-culture and fisheries (Environmental Protection duction of the harmful by-product N2O increas-Agency, 2005; Belsky, Matze and Uselman, 1999; es. This suboptimal nitrification occurs whenOngley, 1996; Carpenter et al., 1998). ammonia is washed directly from the soil into138
    • Livestock’s role in water depletion and pollutionthe water resources (Whitmore, 2000; Carpenter The serious water pollution threat represent-et al., 1998). ed by industrialized livestock production sys- Leaching is another mechanism whereby N is tems has been widely described. In the Unitedlost to water resources. In its nitrate (NO3) form States, for example, Ritter and Chirnside (1987)(inorganic N), nitrogen is very mobile in soil solu- analysed NO3-N concentration in 200 ground-tion, and can easily be leached below the rooting water wells in Delaware (cited in Hooda et al.,zone to the groundwater, or enter the subsurface 2000). Their results demonstrated the high localflow. Nitrogen (especially its organic forms) can risk presented by industrial livestock productionalso be carried into water systems through run- systems: in poultry production areas, the meanoff. The high levels of nitrate observed in water concentration rate was 21.9 mg/litres comparedcourses close to grazing areas are mainly the to 6.2 for corn production areas and 0.58 for for-result of groundwater discharges and subsur- ested areas. In another study in Southwest Walesface flow. When manure is used, as an organic (United Kingdom), Schofield, Seager and Mer-fertilizer, much of the nitrogen losses after riman, (1990) show that a river draining exclu-application are associated with mineralization sively from livestock farming areas was heavilyof soil organic matter at a time when there is no polluted with background levels of 3-5 mg/litrescrop cover (Gerber and Menzi, 2005; Stoate et al., of NH3-N and peaks as high as 20 mg/litres. The2001; Hooda et al., 2000). high peaks may be after rains, because of waste High levels of nitrate within water resources washing from farm backyards and manuredmay represent a health hazard. Excessive levels fields (Hooda et al., 2000).in drinking water may cause methemoglobin- Similarly, in Southeast Asia the LEAD initiativeemia (“blue baby syndrome”) and can poison analysed the land-based sources of pollution tohuman infants. Among adults, nitrate toxicity the South China Sea, with particular emphasismay also cause abortion and stomach cancers. on the contribution of the growing swine industryThe WHO guide value for nitrate concentration in China, Thailand, Viet Nam and China’s Guang-in drinking water is 45 mg/litre (10 mg/litre for dong province. Pig waste was estimated to beNO3-N) (Osterberg and Wallinga, 2004; Bellows, a greater contributor to pollution than human2001; Hooda et al., 2000). Nitrite (NO2-) is just domestic sources in the three countries. Theas susceptible to leaching as nitrate, and is far share of nutrient emissions in water systemsmore toxic. attributable to pig waste ranges from 14 per-Table 4.9Estimated relative contribution of pig waste, domestic wastewater and non-point sources to nitrogen andphosphorus emissions in water systemsCountry/Province Percentage contribution to nutrient emissions in water systems Nutrient Potential load Pig Domestic Non-point (tonnes) waste wastewater sourceChina-Guangdong N 530 434 72 9 19 P 219 824 94 1 5Thailand N 491 262 14 9 77 P 52 795 61 16 23Viet Nam N 442 022 38 12 50 P 212 120 92 5 3Source: FAO (2004d). 139
    • Livestock’s long shadowcent for N and 61 percent for P in Thailand to 72 Table 4.10percent for N and 94 percent for P in the China’s Ranges of BOD concentration for various wastes andGuangdong province (see Table 4.9) (Gerber and animal productsMenzi, 2005). Source BOD (mg/litre) Milk 140 000Phosphorus: Phosphorus in water is not consid- Silage effluents 30 000–80 000ered to be directly toxic to humans and animals Pig slurry 20 000–30 000and, therefore, no drinking-water standards have Cattle slurry 10 000–20 000been established for P. Phosphorus contami- Liquid effluents draining fromnates water resources when manure is directly slurry stores 1 000–12 000deposited or discharged into the stream or when Dilute dairy parlour andexcessive levels of phosphorus are applied to the yard washing (dirty water) 1 000–5 000soil. Unlike nitrogen, phosphorus is held by soil Untreated domestic sewage 300particles and is less subject to leaching unless Treated domestic sewage 20–60concentration levels are excessive. Erosion is Clean river water 5in fact the main source of phosphate loss and Source: MAFF–UK (1998).phosphorus is transported in surface runoff insoluble or particulate forms. In areas with highlivestock densities phosphorus levels may build Table 4.10 presents the BOD levels for variousup in soils and reach water courses through wastes in England. Livestock-related wastes arerunoff. In grazing systems cattle treading on soil among those with the highest BOD. The impactsaffects the infiltration rate and macroporosity, of total organic carbon and associated levels ofand causes loss of sediment and phosphorus via BOD on water quality and on the ecosystemsoverland flow from pasture and cultivated soil have been assessed at the local level but lack of(Carpenter et al., 1998; Bellows, 2001; Stoate et data make extrapolation at higher scales impos-al., 2001; McDowell et al., 2003). sible.Total organic carbon reduces oxygen levels in Biological contamination represents a publicwater health hazardOrganic waste generally contains a large pro- Livestock excrete many zoonotic micro-organ-portion of solids with organic compounds that isms and multi-cellular parasites of relevancecan threaten water quality. Organic contamina- to human health (Muirhead et al., 2004). Patho-tion may stimulate proliferation of algae, which genic micro-organisms can be water-borne orincreases their demand for oxygen and reduces food-borne, especially if the food crops areavailable oxygen for other species. The bio- watered with contaminated water (Atwill, 1995).logical oxygen demand (BOD) is the indicator High quantities of pathogens have usually to beusually used to reflect water contamination by directly discharged for an effective transmissionorganic materials. A literature review by Khaleel process to occur. Several biological contami-and Shearer, (1998) found a strong correlation nants can survive for days and sometimes weeksbetween high BOD and high livestock numbers in the faeces applied on land and may later con-or the direct discharge of farm effluents. Rain taminate water resources via runoff.plays a major role in the variation of BOD levels The most important water-borne bacterialin streams draining livestock areas, unless farm and viral pathogens that are of primary impor-effluents are directly discharged into the stream tance to public health and veterinary public(Hooda et al., 2000). health are:140
    • Livestock’s role in water depletion and pollution Campylobacter spp.: Various species of cam- and D cause most cases of botulism in animals.pylobacter have an important role in human C. botulinum can be transported through runoffgastrointestinal infection. Worldwide, campy- from fields (Carney, Carty and Colwell, 1975;lobacteriosis is responsible for approximately Notermans, Dufreme and Oosterom, 1981).5‑14 percent of all cases of diarrhea (Institute Viral diseases: Several viral diseases can alsofor International Cooperation in Animal Bio- be of veterinary importance and may be associ-logics, Center for Food Security and Public ated with drinking water such as PicornavirusHealth, 2005). Several cases of human clinical infections (Foot-and-mouth disease, Teschen/illness attributable to water contaminated by Talfan disease, Avian encephalomyelitis, Swinelivestock have been documented (Lind, 1996; vesicular disease, Encephalomyocarditis); Par-Atwill, 1995). vovirus infections; Adenovirus infections; Rin- Escherichia Coli O157: H7: E. Coli O 157:H7 is derpest virus; or Swine fever.a human pathogen that can cause colitis and in Livestock parasitic diseases are transmit-some cases hemolytic uremia syndrome. Cattle ted either by ingesting environmentally robusthave been implicated as a main source of con- transmissive stages (spores, cysts, oocysts, ova,tamination in water-borne and food-borne E.coli larval and encysted stages) or via use of con-O157-H7 outbreaks and sporadic infections. taminated water in food processing or prepara-Complications and deaths are more frequent in tion, or via direct contact with infective parasiticyoung children, the elderly and those with debili- stages. Cattle act as a source of parasites fortating illnesses. In the United States, approxi- human beings and many wildlife species (Olsonmately 73 000 infections are reported to occur et al., 2004; Slifko, Smith and Rose, 2000). Excre-yearly (Institute for International Cooperation in tion of transmissible stages can be high, and theAnimal Biologics, Center for Food Security and threat to veterinary public health may extend farPublic Health, 2004; Renter et al., 2003; Shere et beyond the contamination areas (Slifko, Smithal., 2002; Shere, Bartless and Kasper, 1998). and Rose, 2000; Atwill, 1995). Among the para- Salmonella spp.: Livestock are an important sites the most important water-related publicsource for several Salmonella spp. infectious to health hazards are Giardia spp., Cryptosporidiahumans. Salmonella dublin is one of the more spp., Microsporidia spp. and Fasciola spp.frequently isolated serotypes from cattle and a Giardia lamblia and Cryptosporidium par-serious food-borne pathogen for humans. Sur- vum: Both are protozoan microbes that canface water contaminated with bovine S. dublin cause gastrointestinal illness in humans (Buretor foods rinsed in contaminated water may et al., 1990; Ong, 1996). G. lamblia and C. parvumserve as vehicles of human infection. Salmo- have become significant water-borne pathogensnella spp. have been isolated from 41 percent of as they are indigenous infections in many animalturkeys tested in California (United States) and species. Their oocysts are small enough to con-50 percent of chickens examined in Massachu- taminate groundwater, and C. parvum oocystssetts (United States) (Institute for International cannot be successfully removed by commonCooperation in Animal Biologics, Center for Food water treatment (Slifko, Smith and Rose, 2000;Security and Public Health, 2005; Atwill, 1995). East Bay Municipal Utility District, 2001; Olson Clostridium botulinum: C. botulinum (the et al., 2004). Worldwide, the prevalence in humanorganism that causes botulism) produces potent population is 1 to 4.5 percent in developed coun-neurotoxins. Its spores are heat-resistant and can tries and 3 to 20 percent in developing countriessurvive in foods that are incorrectly or minimally (Institute for International Cooperation in Animalprocessed. Among the seven serotypes, types A, Biologics, Center for Food Security and PublicB, E and F cause human botulism, while types C Health, 2004). 141
    • Livestock’s long shadow Microsporidia spp: Microsporidia spp are Hormones are used to increase feed conversionintracellular spore-forming protozoa. Fourteen efficiency, particularly in the beef and pig sector.species are identified as opportunistic or emerg- Their use is not permitted in a series of coun-ing pathogens for human beings. In developing tries, particularly in Europe (FAO, 2003a).countries, Microsporidia species represent an In developed countries, drug use for animaleven greater public health hazard, as infections production represents a high share of total use.were found predominantly in immuno-compro- About half of the 22.7 million kg of antibioticsmised individuals. The disease is usually borne, produced in the United States annually is usedbut it is also a potential emerging meat-borne on animals (Harrison and Lederberg, 1998). Thezoonosis, which may also be acquired from Institute of Medicine (IOM) estimates that aboutraw or lightly cooked fish or crustaceans. The 80 percent of the antibiotics administered to live-presence of human pathogenic Microsporidia in stock in the United States are used for non-ther-livestock or companion animals has been widely apeutic reasons, i.e. for disease prophylaxis andreported. Enterocytozoon bieneusi (the most growth promotion (Wallinga, 2002). In Europe,frequently diagnosed species in humans) was the amount of antibiotics used decreased afterreported in pigs, cattle, cats, dogs, llama and 1997, as a result of prohibition of some of thechickens (Slifko, Smith and Rose, 2000; Fayer et substances and public discussion on their use.al., 2002). In 1997, 5 093 tonnes were used, including 1 599 Fasciola spp.: Fasciolosis (Fasciola hepatica tonnes as growth promoters (mostly polyetherand Fasciola gigantica) is an important parasitic antibiotics). In 1999, in EU-15 (plus Switzerland)infection of herbivores and a food-borne zoono- 4 688 tonnes of antibiotics were used in livestocksis. The most common transmission route is the production systems. Of these 3 902 tonnes (83ingestion of contaminated water. Food (such as percent) were used for therapeutic reasons (tet-salads) contaminated with metacercariae-con- racyclines were the most common group) whiletaminated irrigation water may also be a pos- only 786 tonnes were used as growth promot-sible transmission route (Slifko, Smith and Rose, ers. The four feed additives substances left in2000; Conceição et al., 2004; Velusamy, Singh the EU (monensin, avilamycin, flavomycin andand Raina, 2004). salinomycin) will be prohibited in the EU by 2006 (Thorsten et al., 2003). The World Health Organi-Drug residues contaminate aquatic environments zation (WHO) has recently called for a ban on thePharmaceuticals are used in large quantities practice of giving healthy animals antibiotics toin the livestock sector, mainly antimicrobials improve their productivity (FAO, 2003a).and hormones. Antimicrobials have a variety of No data are available on the amounts of hor-use. They are given for therapeutic purposes mones used in the different countries. Endo-to animals but are also given prophylactically crine disruptors interfere with the normal func-to entire groups of healthy animals, typically tion of body hormones in controlling growth,during stressing events with high risk of infec- metabolism and body functions. They are usedtions, such as after weaning or during transport. in feedlots as ear implants or as feed additivesThey are also given to animals routinely in feed (Miller, 2001). The natural hormones commonlyor water over longer periods of time to improve used are: estradiol (estrogen), progesterone, andgrowth rates and feed efficiency. When antimi- testosterone. The synthetic ones are: zeranol,crobials are added to feed or water at lower- melengestrol acetate, and trenbolone acetate.than-therapeutic rates some scientists refer to Around 34 countries have approved hormonesthem as “subtherapeutic” or “nontherapeutic” for use in beef production. Among them are the,uses (Morse and Jackson, 2003; Wallinga, 2002). Australia, Canada, Chile, Japan, Mexico, New142
    • Livestock’s role in water depletion and pollutionZealand, South Africa and the United States. possible endocrine disruption in humans andWhen hormones are used cattle experience an 8 wildlife (Miller, 2001). Trenbolone acetate canto 25 percent increase in daily weight gain with up remain in manure piles for more than 270 days,to a 15 percent gain in feed efficiency (Canadian suggesting that water can be contaminated byAnimal Health Institute, 2004). No negative direct hormonally active agents through runoff forimpacts on human health as a result of their cor- example. The links between livestock use of hor-rect application have been scientifically proven. mones and associated environmental impacts isHowever, the EU, partly in response to consumer not easily demonstrated. Nevertheless, it wouldpressure, has taken a strict stand on the use of explain wildlife showing developmental, neuro-hormones in livestock production (FAO, 2003a). logic, and endocrine alterations, even after the However, a substantial portion of the drugs ban of known estrogenic pesticides. This sup-used is not degraded in the animal’s body and position is supported by the increasing numberends up in the environment. Drug residues of reported cases of feminization or masculin-including antibiotics and hormones have been ization of fish and the increased incidence ofidentified in various aquatic environments breast and testicular cancers and alterations ofincluding groundwater, surface water, and tap male genital tracts among mammals (Soto etwater (Morse and Jackson, 2003). The US Geo- al., 2004).logical Survey found antimicrobial residues in 48 Antimicrobials and hormones are not the onlypercent of 139 streams surveyed nationwide and drugs of concern. For example, high quantitiesanimals were considered possible contributors, of detergents and disinfectants are used in dairyespecially where manure is spread over agri- production. Detergents represent the biggestcultural land (Wallinga, 2002). For hormones, portion of chemicals used in dairy operations.Estergreen et al. (1977) reported that 50 per- High levels of antiparasitics are also used in live-cent of progesterone administrated to cattle stock production system (Miller, 2002; Tremblaywas excreted in the faeces and 2 percent in the and Wratten, 2002).urine. Shore et al. (1993) found that testosteronewas readily leached from soil, but estradiol and Heavy metals use in feed return to theestrone were not. environment Since even low concentrations of antimicro- Heavy metals are fed to livestock, at low con-bials exert a selective pressure in freshwater, centrations, for health reasons or as growthbacteria are developing resistance to antibiot- promoters. Metals that are added to livestockics. Resistance can be transmitted through the rations may inclu