Abstract:
Agricultural water structure (AWS) influences the efficiency and potential benefits of water use. The evolution history of AWS in China was analyzed in this study using agricultural water consumption data in China for 1949~2006. Agricultural water use level for 1949~2050 was divided into four periods of primary use, low efficiency use, reasonable use and high efficiency use in accordance with the evolution history and tendency of future AWS. The analysis shows that AWS in China is improving as the proportion of agricultural water consumption to total water use is steadily decreasing. The level of water use is increasingly harmonized among agriculture, forestry, herding and fishing as well as water consumption by grain crops, cash crops and grazing grass. The concept of economic agricultural water consumption is advanced, emphasizing water-saving via optimized AWS. A case study of North China illustrates that AWS optimization increases water use benefits and saves 199.94×108 m
3 water per year. Integrative water-saving measures along with optimized AWS saves an additional 29.97×108 m
3 water per year over water-saving measures alone.