ABSTRACT
Previous chapters have focused on food needs. This chapter introduces the challenges and threats that must be addressed if food needs are to be met in a sustainable and equitable way. Challenges and threats introduced here include demographic change, water scarcity, land degradation, climate change, energy insecurity, and loss of ecosystem services. Demographic change, along with income growth and urbanization, determines the shape of future food needs. Food insecurity will increasingly be concentrated in low-income and food-insecure countries where population growth remains relatively high. Water scarcity is becoming a major threat to sustainable production where food demand is rising (especially for “water-intensive” products such as fresh fruits and vegetables); where competition is increasing between agricultural and nonagricultural uses of water; and where river basins are “closing,” meaning that the demand for water has come to exceed its supply and rivers no longer reach the sea. Climate change has also come to be recognized as a threat to sustainable food production. Analysis of multiple scenarios suggests that climate change will have serious distributional impacts across countries, with poor countries
Abstract .................................................................................................................. 235 Introduction ............................................................................................................ 236 Demographic Change ............................................................................................. 236 Water Scarcity ........................................................................................................ 237 Land Degradation ................................................................................................... 239 Climate Change ......................................................................................................240 Energy Insecurity ................................................................................................... 241 Loss of Ecosystem Services ................................................................................... 243 Interrelationships ....................................................................................................244 Moving Forward ....................................................................................................245 Conclusions and Study Topics ...............................................................................245 References ..............................................................................................................246
in warm environments suffering the most. Questions of energy insecurity pose further threats. Higher energy prices will make manufacturing and applying fertilizer, running farm machinery, pumping water, and transporting inputs and marketing products more expensive. A final threat to sustainable food production is the loss of ecosystem services. Past successes in producing food may be part of a larger process that threatens future food production. Agriculture will need technical, institutional, and policy innovations to achieve sustainable improvements in productivity, equity, and resilience through advances in the management of energy, soils, water, livestock, and crops.
