Estimation and influencing factors of agricultural water efficiency in the Yellow River basin, China

As an important grain production base in China, the Yellow River basin (YRB) plays an important role in China's economic development and ecological security. However, with increasing agricultural water environmental problems and deteriorating water quality, the agricultural water situation in the YRB is grim. Under the background of comprehensively promoting the high-quality development of the YRB, improving agricultural water efficiency can reduce the constraint effect of insufficient water resources on agriculture and improve the water ecological environment, which will help achieve coordinated social, economic and environmental development. In this study, agricultural water efficiency of nine provinces in the YRB from 2008 to 2017 was measured by the super-efficient slack-based measured Data Envelopment Analysis (SBM-DEA) method with unexpected outputs, spatial autocorrelation analysis and the Malmquist index, and the key influencing factors were identified by the spatial Tobit regression model. The results showed that the agricultural water efficiency of nine provinces in the YRB was increasing, with large differences among provinces and little spatial correlation, presenting a spatial distribution with the lower reaches higher than the middle reaches and the middle reaches higher than the upper reaches; the change in the Malmquist index of agricultural water showed an increasing trend, which was mainly determined by the technical progress. Additionally, the economic development level and water resource endowment had positive effects on agricultural water efficiency, while government expenditure and urbanization level had significant negative correlation with agricultural water efficiency.