Livestock production and the water challenge of future food supply: implications of agricultural management and dietary choices

摘要: Abstract Human activities use more than half of accessible freshwater, above all for agriculture. Most approaches reconciling water conservation with feeding a growing population focus on the cropping sector. However, livestock production is pivotal to agricultural resource use, due its low resource-use efficiency upstream in food supply chain. Using global modelling approach, we quantify current and future contribution production, under different demand- supply-side scenarios, consumption “green” precipitation infiltrated into soil “blue” freshwater withdrawn from rivers, lakes reservoirs. Currently, cropland feed accounts 38% crop grazing involves 29% total (9990 km3 yr−1). Our analysis shows that changes diets productivity have substantial implications blue (19–36% increase compared levels) green (26–69% increase), but they can, at best, slow down trends rising requirements decades come. moderate reductions highly intensive systems are possible without aggravating scarcity. Productivity gains developing regions decrease consumption, lead expansion irrigated agriculture, shift grassland/green cropland/blue resources. While magnitude footprint gives cause concern, neither dietary choices nor will solve challenge supply, unless accompanied by dedicated protection policies.