Pute Wu
Institute of Soil & Water Conservation, Northwest A&F University
Water shortage and its uneven distribution are important issues which affect grain production of China. It is one of the focuses in the world that whether China’s water resources could support its grain production. The contradiction between the increase of grain needs and shortage of agricultural water resources is one of the challenges that facing agricultural water use in China. This paper analyzed the spatial and temporal evolution of grain production, water footprint for grain production and regional virtual water flows in 1951-2010 after introducing the concepts of water footprint for grain production and virtual water flow. The results include: since 2000s, major grain production areas were changed from South China to North China; the virtual water flows caused by the grain transfer from North to South China was as high as 53.00 billion m3, which was more than the runoff of the Yellow River. This phenomenon will exist for a long time which is the new challenge facing grain production in China; The water footprint for grain production of China decreased from 3.38 m3/kg in 1950s to 1.31 m³/kg in 2000s. The differences of water footprints in regions were significant.In2000s, the highest and lowest values were 2.27 m³/kg and 0.83 m³/kg respectively. Considering the water resources problems for grain production in China, we should develop water-saving agriculture, build regional standards for water footprint for grain production and related compensation policy, and promote the water transfer project from South to North China.
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