Analysis of Water Resources Utilization Efficiency and Its Affecting Factors in Grain Production: An Empirical Research Based on China's Inter-Provincial Panel Data

Super-efficient SBM model was performed to explore the temporal and spatial characteristics of the comprehensive efficiency, the pure technical efficiency and the scale efficiency of water resources utilization in grain production from 2008 to 2017 in China. Tobit model was applied to examine the impact of natural environment and irrigation strategies on water resources utilization efficiency. The results show that there was still much room for improvement in the water resources utilization efficiency in China. The comprehensive efficiency and pure technical efficiency showed an inverted "U" trend, whereas the scale efficiency showed an increasing trend before 2011, and then maintained stable. The scale efficiency was higher over the coastal areas compared to the inland areas. The low technical efficiency contributed to the low comprehensive efficiency in the main grain-producing areas including the northern coastal region, northeast China and the middle reaches of the Yangtze river, while the low comprehensive efficiency over the middle reaches of the Yellow River and the southwest was mainly due to the low scale efficiency. Both effective irrigation and grain breeding techniques made positive contribution to the three efficiencies, while negative contribution was due to the rural water source construction. Further, the disaster degree also showed a negative impact on the comprehensive efficiency and the scale efficiency. Finally, proposals for improving water resources utilization efficiency are suggested based on our analysis.