Conservation Agriculture Jack McHughPictures and text (in part) by Dr Des McGarryContributions from Dr Jack Desbiolles (Ashworth et al., 2010) and Baker et al., (2007)
Mitigating Land Degradation & Improving Land and Environment Condition from Local to Global level viaConservation Agriculture
Conservation Agriculture (CA) Farming in a natural way Represents:“a shift in our philosophy towards the land” “do not beat the land into submission - rather work in harmony with it”
What is the goal of CA?To conserve, improve and make moreefficient use of natural resources throughintegrated management of available soil,water and biological resources combinedwith external inputs. CA is a resource-efficient and resource-effective form of agriculture.
What is Conservation Agriculture ? The foundation underlying the three principles is their contribution and interaction with soil carbon, the primary determinant of long term sustainable soil quality and crop production Baker et al., (2007)
CA is about feeding and greening the world for global sustainability. Baker et al., (2007) Agricultural policies: to encourage farmers – leads toincreased air & water quality and productivity, and mitigates GHGs
Conservation Agriculture- a question of how much soil disturbance It is a question of soil disturbance – Reduced tillage = Intermediate in Organic soil quality effects. farming They define the tillage Zero till equipment & operation Conservation characteristics as they tillage relate to the soil volume No till Direct disturbed and the Direct planting degree if residue mixing. Seeding PRB Direct True Conservation = drill Carbon & soil moisture Ridge Management Baker et al., (2007) Controlled Mulch tillage Strip Precision traffic tillage tillage Ag farming Minimum Reduced till tillage
Philosophy of CAThere is nothing wrong with our soils except our interference. It can be said withconsiderable truth the use of tillage has actually destroyed the productivity of our soils.(Faulkner, 1942) „Soil does not need tillage for effective crop production‟ -This is the basis for the CA philosophy- Tillage is not necessary for crop production. Crop residues are a very valuable part of farming systems and must be retained in full and remain on the surface as a mulch. Permanent all year round soil cover is essential. Control and promotion of natural biological soil process through rotation. Soil degradation and erosion is a symptom of an unsuitable farming system. Vehicle traffic management is adopted within an integrated systems approach. Ashworth et al., (2010)
Important benefits of CA Increased SOM Improved soil quality Increased available plant nutrients Less runoff and increased plant available water Reduced soil erosion Improved crop production economics Reduced labour requirements Reduced machinery costs Reduced fossil fuel inputs Improved global environmentFredrick Movie + & - impact of CA……..aware of issues – farmer support/networks Nutrient Efficiency………Dynamics, VAM, Rhizobia, rooting environment Sustainability role……….Drought, erosion, WUE CA in Canada…………….Lot to learn Rotations, residue, demands for crops – force farmers tomonocultures
CROP ROTATIONS in CA - are “critical” - Disease control - Nitrogenous plants - Biodiversity
Improved soil biodiversity… 3 years no-till on a Russian chernozem on the Pampas of Argentina – 12 years zero till Roberto Pieretti
Organic Carbon levels with No-till Increases – reported globally Soil Carbon data for the 12 Years of No Till (N) and conventional (C) sites (Walkley and Black extracted OC) C W&B Depth (%) (cm) N C 0 - 10 1.54 0.89 10 - 20 1.45 0.81 20 - 30 1.34 0.71Almost 50 % more OC in the no-till site – to 30 cm - 12 years of No-Till McGarry and Sharp, ISTRO, 2003
From - Emilio-Jesús GONZÁLEZ-SÁNCHEZ. AEAC.SV – ECAF – University of Córdoba
Weed Control with No-tillEnvironmental concerns with continued usage of herbicides Proven reduced Glyphosate (Roundup) use with time under No - Till Simba (1999). ECO tillage reduces inputs and maximises crop yields. Simba International Ltd., Sleaford, Lincolnshire, England. pp. 26.
Most commonperception of CA Jose Benites, FAO Large fields – wheat, cotton, soybean, maize…
CA is applicable to virtually all crops Cucumber Sweet pepper Onions LABRANZA PÓS COSECHA DE Cassava Jose Benites, FAO Tomato Squash
Hoe-based farming, 0.5 ha farms; red sandy loam, Zambia Peter Aagard and Dutch Gibson, CFU, Lusaka, Zambia 40,000ha of CA Consequences: - vast labour & time needs - yield losses if it rains - total loss if drought - widespread erosion (see arrows)Conservation Agriculture: Video- using “planting basins”- retain crop residues- + rotation crops- 80% time saving (“drudgery”)- land ready before rains- yields up 65 to 75% (maize & cotton)- hunger alleviated- with less resources used
Machinery based, 1850 ha ; Australia; wheat and sorghum; 500mm rain/yr “I farm for my soil moisture”No-till (5 yrs), controlled traffic (2 m); 1 tractor (240hp), 1 disc planter, 1 spray-coupe, 1 operator Excellent soil structure 12Mha of CA - extended farm to unproductive clay loams; soil greatly improved - land doubled in value; crops every year; 0.5 t/ha wheat in drought year
Machinery based, China ACIAR project: 96/143: “Sustainable Mechanised Dryland Grain Production” China Agricultural University - University of Queensland, Shanxi Agricultural Machinery Bureau J.N.Tullberg, D. Freebairn, Prof. Gao Huanwen, Dr Zhai Tongyi Experimental sites: - Linfen and Shouyang (Shanxi province) – start: 1997 - Zhangbei and Western Shanxi (northern Hebei) - 1999 1.3Mha of CA (2009)RESULTS: Water erosion increased by:• tillage (by 30%)• random traffic, tillage and residue burial (by 70%)• residue removal from tilled soil by (~105%) Conventional• wheel compaction, residue removal in no-till (by >200%) Zero tillThis project has demonstrated - No-Till with controlledtraffic:1. reduces power requirements2. enhances the productivity and sustainability of cropping3. by avoiding the damaging soil energy inputs4. alternate, cheaper and more sustainable methods toconventional farming in these areas…
Same Result – Foggia, eastern Italy 80,000 ha of CA (2009) Conventional till No-till 2.65 t/ha 2.11 t/ha Protein: 15.5% Protein: 11.4%Strong visible evidence of improved utilisation of rainfall..
Foggia trial results:: grain yield of durum wheat 5 Conventional tillage 412 Sod seeding 4 310 393Grain yield (t/ha) 288 319 3 226 324 280 2 1 0 1995 1996 1997 1998 1999 2000 2001 Average No-till “best” in driest years (1997 and 2001) Data and graph from Professor Michele Pisante
0.65 Mha of CA (2009)From - Emilio-Jesús GONZÁLEZ-SÁNCHEZ AEAC.SV – ECAF – University of Córdoba
Brazil, 600 ha ; Brazil – Herbert Bartz; maize and wheat; 800mm rain/yr No till for 45 years !!! 25.5 Mha of CA (2009) Excellent soil structure - without cultivation
China, 0.5ha; Hexi Corridor; maize and wheat; 150mm rain/yr No till for 4 years Darker colour, earthy, rough, soft, SOMTraditional farming New beds each year (FRB)Grey colour,blocky, hard, smooth ZT CTF PRB
Evolutionary phases of no-till farming (Sá, 2004) Rolf Derpsch identified that growers practicing a no till system without full stubble retention will probably never leave the initial phase.
What are the issues?Converting to CA needs higher management skillsThe first years might be very difficult for thefarmers, therefore they might need support –from other farmers or from extension services –and perhaps even financial support to invest innew machinery such as zero-till plantersNecessary technologies are often unavailableFew farmers take the risk of buying newmachineryMachinery dealers might not wish to promote CA
Extension of CA?Training, Educational, Empowering Participatory activities courses, seminars, forums, workshops, field days, farm trial sites, farmer field schools for farmers, agronomists & technologists
FAO FAO CA field training in Embu/Kenya CA and Gender training – Machakos/Kenya FAO FAOWomen with beans under CA, Karatu/Tanzania Field day in Karatu/Tanzania with jab planter demonstrations
Soil pit day - Swaziland FFS- Zhangye, Gansu Farmer & technologist empowering days..Australia: “harness the power of local farmers” Uzbekistan: with tractor sales personnel
The many attractions andmultiple ecosystem level benefits of Conservation Agriculture * Farm Communities Environment Watershed Global * http://www.fao.org/ag/ags/AGSE/agse_e/general/OBJECT.htm and John Landers (2000) – World Bank Report
Multiple ecosystem level benefits of CAFarm – level: Reduction in labour, time (less drudgery), fuel and costs On mechanised farms: smaller tractors possible (up to 40% smaller) longer lifetime and less maintenance of tractors (life x2 or x3) less power and fewer passes hence reduced fuel consumption (up to 50%) Better trafficability in the field – from controlled traffic Earlier sowing (soil preparation eliminated) Increased yields with decreased inputs More stable yields, particularly in dry years Improved infiltration and crop water use efficiencies From - Emilio-Jesús GONZÁLEZ-SÁNCHEZ AEAC.SV – ECAF – University of Córdoba From: better soil structure, biodiversity & OM levels Increased profit, at times from the beginning, after a few years.
Multiple ecosystem level benefits of CACommunities/Environment/Watershed: More constant water flows in the rivers, re-activation of wells Cleaner water due to less erosion Less flooding Less impact of extreme climatic situations Less costs for road and waterway maintenance Better food security Increased wildlife (species and populations) in fields (protected by retained residues; fed by increased biodiversity)
At global level: Multiple ecosystem level benefits of CACarbon sequestration (reduction of greenhouse effect): CA farmers could receive carbon-grant payments; Carbon sequestration and reduced energy (fuel) use could = the human-induced increase in CO2.Less fuel use in agricultureReduced CO2e emissions, and heat (fossil fuel burning)Less leaching of nutrients and chemicals intogroundwater.Less pollution of waters (river, lake, reservoir, ocean)Greatly reduced erosion (wind and water)Recharge of aquifers through better infiltration
Finally… It is strongly possible & very practical…to achieve Multiple ecosystem level benefits with… Conservation Agriculture