Accounting for virtual water in food products antonelli marta greco francesca fsdl2012


Published on

Accounting for virtual water in food products

1 Like
  • Be the first to comment

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide

Accounting for virtual water in food products antonelli marta greco francesca fsdl2012

  1. 1. NOT ALL WATER DROPS ARE THE SAME Accounting for virtual water in food products Authors: Marta Antonelli and Francesca Greco, King’s College London,, NOT ALL TOMATOES ARE THE SAMEINTRODUCTION 1 BACKGROUND CONCEPTS 2The aim of this poster is to present a framework for appraising Virtual water: Virtual water is the water embedded in commodities, which Allan conceptualised in 1993. Accordingly, virtual water ‘trade’ refers to the water ‘embedded’ in traded products that is ‘exchanged’ among different trade partners.the sustainability of food products in terms of water resources Green water resources: Green water is rainwater directly used and evaporated by non-irrigated agriculture, pastures and forestsuse. For this purpose, we will first provide a tool to describe the Blue water resources: Blue water is the source of supply. It is equivalent to the natural water resources (surface and groundwater runoff).different typologies of virtual water embedded in crops. Renewable water resources: Renewable water resources are computed on the basis of the water cycle. In this report, they represent the long-term average annual flow of rivers (surface water) and groundwater.Secondly, we will present a matrix for appraising the different Non-renewable water resources: Non-renewable water resources are groundwater bodies (deep aquifers) that have a negligible rate of recharge on the human time-scale and thus can be considered non-renewable.degrees of sustainability associated with the production of Food water and non-food water: Global water resources can be categorised as either food-water or non-food water resources. Non-food water can only be blue water and accounts for roughly 10% of the water needed by an individual or an economy. Food-water instead, accountsdifferent crops. Thirdly, we will illustrate concrete cases and for nearly 90% of the water requirements of an individual or an economy, and can be both green and blue water (Allan 2012).provide an individual appraisal for each example. APPRAISING VIRTUAL WATER SUSTAINABILITY: 4 Categorization of agricultural blue THE MATRIX The matrix provided below is a framework through which it is possible to conduct a comprehensive evaluation of the hydrological impact and sustainability of different and green water sources and crop productions. This framework allows us to position different crops in the matrix and to evaluate each case in terms of sustainability and related impact. As their contribution to crop illustrated, the impact of a certain agricultural production is given by three main components impacting virtual water sustainability: the source of water (green and/or production. blue), the renewable/non-renewable nature of the water used, and the site of production in a water-scarce or water-rich area. We will find that the best impact on water systems is provided by rainfed agriculture, where green water sustains the crop during the entire production process and Green/Blue water are always in there is no need to use blue water. This “best impact” is reachable and valid in both water-rich and water-scarce areas. The second best impact is reached when blue constant interaction and we have water from a renewable blue source is used in a water-rich area. From here on, the three worst impacts take place: first, in a water-rich area which uses predominantly here simplified the prevalence of non-renewable blue water; secondly, in water-scarce area which uses predominantly renewable blue water; and finally, the worst impact is verified when we are in a one over the other component water-scarce area whose agricultural sector relies on non-renewable blue water resources. Climatic zones and income level are here included as descriptive features into 5 types of interactions which are, nonetheless, useful to show that it is not sufficient to operate in a rich country to act sustainably, and that, equally, it is not taken for granted that if you are in a desert area you cannot pursue sustainability. CONCLUSIONS 5 Not all water drops are equal and not all tomatoes are equal. The analysis suggests that each crop production should be evaluated and pursued in the light of its VIRTUAL WATER TYPOLOGIES: A 3 environmental and, consequently, economic impacts. Accounting for virtual water typologies and their DESCRIPTIVE FRAMEWORK sustainability allow us to evaluate the risks and the opportunities offered to a crop producer or investor by the production of different crops in different The table provided below is a descriptive framework to classify the different typologies of virtual water ‘embedded’ in food products. The variables illustrated refer to the source of water; the nature of the contexts. By making visible the typologies of water resource; the site of production; the climatic characteristics; the level of income. involved in food production, we aim to promote the As illustrated, the source of virtual water can be totally green (100% green water); predominantly green approaches which give priority to green water (75% green water); equally green and blue (50% each); predominantly blue (75% blue water); totally blue utilization and to a conscious use of renewable of blue (100% blue water). Virtual water can originate from either renewable or non-renewable water bodies. The water, avoiding non renewable sources when feasible. site of production can be water rich or water scarce (economically and/or physically); and can be classified We argue that it is possible to produce with a good EXAMPLES OF CROPS as humid, moist sub-humid, sub-humid, semi-arid, arid, desert. Finally, a classification by level of income is degree of sustainability even in water-scarce countries provided (low-income; lower-middle income; upper-middle income; high-income; high-income OECD if we invest in improving the productivity of green economies). water. At the same time, this framework shows that it should not be taken for granted that high-income countries make the right choices when it comes to water use in agriculture. This applies to the case of Millet and Sorghum countries using predominantly blue water resources in Tanzania and Kenya Tomatoes from Libya, Nubian Aquifer Bananas from Jordan Valley, Jordan Wheat from Ohio, USA Tea from Himachal Pradesh, India Wine from Umbria, Italy and with a unexploited green water potential. Further steps need to be taken in this direction, and we encourage the private sector and decision-makers to engage in this process. Take-home messages • GREEN WATER IS FOR FREE: Implement solutions to measure the availability of green water in the soil, before opening the irrigation tap of your field. • USING NON-RENEWABLE WATER HAS A HIGHT COST: it is risky for a company’s investments, it is dangerous for a company’s reputation in local society; it is costly for electricity and pumping schemes; it is costly for future generations, for a business’s long-run estimates of water availability. Do not invest in it. • SELLING A PRODUCT WITH HIGH WATERREFERENCES: Allan J.A. (1993), “Fortunately there are substitutes for water otherwise our hydro-political futures would be impossible”, Priorities for water resources allocation and management, ODA, pp. 13-26, London- Allan J.A. (2012), “Food-water security: beyond water and the water sector”, in Lankford B., Bakker K., Zeitoun M., and Conway D., Water security: principles, SUSTAINABILITY IS GIVING A POSITIVE MESSAGE TOperspectives, practices, Earthscan, London.- CAMWA 2007. Water for Life: A comprehensive Assessment of Water Management in Agriculture. London: Earthscan.- Food and Agriculture Organisation of United States *FAO+ (2003), “Review of World Water Resources by Country”, Water Report 23, Rome. Available online at: CONSUMERS. Food and Agriculture Organisation of United States [FAO] (1986), "Irrigation Water Management: Irrigation Water Needs", Training manual no.3, Rome. Available online at: