Satisfying future water demands for agriculture

The global demand for water in agriculture will increase over time with increasing population, rising incomes, and changes in dietary preferences. Increasing demands for water by industrial and urban users, and water for the environment will intensify competition. At the same time, water scarcity is increasing in several important agricultural areas. We explore several pathways for ensuring that sufficient food is produced in the future, while also protecting the environment and reducing poverty. We examine four sets of scenarios that vary in their focus on investments in rainfed agriculture and irrigation, and the role of international trade in adjusting for national disparities in water endowments. Rainfed agriculture holds considerable potential but requires adequate mechanisms to reduce inherent risks. Irrigation expansion is warranted in places where water infrastructure is underinvested such as sub-Saharan Africa. In South Asia the scope for improving irrigation performance and water productivity is high. International trade can help alleviate water problems in water-scarce areas, subject to economic and political considerations. We examine also a regionally optimized scenario that combines investments in rainfed and irrigated agriculture with strategic trade decisions. Compared to 'business as usual', this scenario reduces the amount of additional water required to meet food demands by 2050 by 80%. Some of that water could be made available for the environment and other sectors. We conclude that there are sufficient land and water resources available to satisfy global food demands during the next 50 years, but only if water is managed more effectively in agriculture.

[1]  P. Q. Hung,et al.  Globalisation of water resources : international virtual water flows in relation to crop trade , 2005 .

[2]  J. Bruinsma.  World Agriculture: Towards 2015/2030: An Fao Perspective , 2002 .

[3]  Johan Rockström,et al.  Water for food and nature in drought-prone tropics: vapour shift in rain-fed agriculture. , 2003, Philosophical transactions of the Royal Society of London. Series B, Biological sciences.

[4]  A. Hoekstra,et al.  Globalisation of water resources: Global virtual water flows in relation to international crop trade , 2005 .

[5]  Arjen Ysbert Hoekstra,et al.  Water Footprint of Bio-energy and other primary energy carriers , 2008 .

[6]  Radhika Vidanage De Silva,et al.  World water demand and supply, 1990 to 2025: scenarios and issues , 1998 .

[7]  A. Chapagain,et al.  Globalisation of Water: Opportunities and Threats of Virtual Water Trade , 2006 .

[8]  J. Rockström,et al.  Balancing Water for Humans and Nature: The New Approach in Ecohydrology , 2004 .

[9]  Carl Folke,et al.  Linkages among water vapour flows, food production and terrestrial ecosystem services. , 1999 .

[10]  R. Jongschaap,et al.  Claims and facts on Jatropha curcas L. : global Jatropha curcas evaluation. breeding and propagation programme , 2007 .

[11]  David Molden,et al.  Accounting for water use and productivity , 1997 .

[12]  Eric Kemp-Benedict,et al.  Looking ahead to 2050: scenarios of alternative investment approaches , 2007 .

[13]  T. D. Mitchell,et al.  A comprehensive set of high-resolution grids of monthly climate for Europe and the globe: the observed record (1901-2000) and 16 scenarios (2001-2100). , 2004 .

[14]  D. Renaulta,et al.  Nutritional water productivity and diets , 2000 .

[15]  I. Shiklomanov.  Appraisal and Assessment of World Water Resources , 2000 .

[16]  Deepak Rajagopal,et al.  Implications of India's biofuel policies for food, water and the poor , 2008 .

[17]  Mark Svendsen,et al.  Trends in water and agricultural development , 2007 .

[18]  M. Giordano,et al.  Biofuels and implications for agricultural water use: blue impacts of green energy , 2008 .

[19]  Göran Berndes,et al.  Bioenergy and water - the implications of large-scale bioenergy production for water use and supply. , 2002 .

[20]  D. Molden.  Water for food, water for life: a comprehensive assessment of water management in agriculture , 2007 .

[21]  Ximing Cai,et al.  Does international cereal trade save water? The impact of virtual water trade on global water use , 2004 .

[22]  Adel A. Kader,et al.  Increasing Food Availability by Reducing Postharvest Losses of Fresh Produce , 2005 .

[23]  C. Pahl-Wostl,et al.  Humans transforming the global water system , 2004 .

[24]  Dennis Wichelns,et al.  The policy relevance of virtual water can be enhanced by considering comparative advantages , 2004 .

[25]  Z. Meral Ozsoyoglu,et al.  Statistical Databases , 1984, VLDB.

[26]  Sandra Postel,et al.  WATER FOR FOOD PRODUCTION : WILL THERE BE ENOUGH IN 2025 ? , 1998 .

[27]  Prem S. Bindraban,et al.  Pathways for increasing agricultural water productivity , 2007 .

[28]  Prabhu Pingali,et al.  Westernization of Asian Diets and the transformation of food systems: Implications for research and policy , 2007 .

[29]  Guenther Fischer,et al.  Global Agro-ecological Assessment for Agriculture in the 21st Century , 2002 .

[30]  J. Rockström,et al.  Managing water in rainfed agriculture , 2007 .

[31]  J. A. Allan,et al.  Virtual Water: A Strategic Resource Global Solutions to Regional Deficits , 1998 .

[32]  Richard E. Howitt,et al.  Water Productivity in Agriculture: Limits and Opportunities for Improvement , 2008 .

[33]  M. Gopalakrishnan,et al.  Agriculture , water , and ecosystems : avoiding the costs of going too far , 2007 .

[34]  Petra Döll,et al.  Global change and global scenarios of water use and availability: An Application of WaterGAP1.0 , 1997 .

[35]  Timothy B. Sulser,et al.  Looking ahead: long-term prospects for Africa's agricultural development and food security , 2005 .

[36]  W. Wallender,et al.  Nutritional water productivity and diets , 2000 .

[37]  Paul Pavelic,et al.  Managing water in rainfed agriculture in the Greater Mekong Subregion. , 2012 .

[38]  J. Rockström,et al.  Sustainable Pathways to Attain the Millennium Development Goals – Assessing the Role of Water, Energy and Sanitation , 2005 .

[39]  D. Molden,et al.  Basin-level use and productivity of water: examples from South Asia , 2001 .

[40]  S. Cook,et al.  Reversing the flow: agricultural water management pathways for poverty reduction , 2007 .

[41]  A. Parant.  [World population prospects]. , 1990, Futuribles.

[42]  David Molden,et al.  Saving Water : From Field to Fork Curbing Losses and Wastage in the Food Chain , 2008 .

[43]  Arjen Ysbert Hoekstra,et al.  Globalization of water , 2008 .

[44]  Eric Viala,et al.  Water for food, water for life a comprehensive assessment of water management in agriculture , 2008 .

[45]  J. Rockström,et al.  Water pressure and increases in food a bioenergy demand implications of economic growth and options for decoupling , 2007 .

[46]  Ximing Cai,et al.  World Water And Food To 2025: Dealing With Scarcity , 2002 .

[47]  Doug Koplow,et al.  Government support for ethanol and biodiesel in the United States , 2006 .

[48]  C. Fraiture.  Integrated water and food analysis at the global and basin level. An application of WATERSIM , 2007 .

[49]  Toshihiko Masui,et al.  Research, part of a Special Feature on Scenarios of global ecosystem services Changes in Nature's Balance Sheet: Model-based Estimates of Future Worldwide Ecosystem Services , 2005 .

[50]  A. Watts,et al.  The Myths of Restoration Ecology , 2005 .