Research on Irrigation Water Efficiency of Guizhou Province Based on SFA

The measurement of farmland irrigation water efficiency is an important part of the evaluation of agricultural water saving. Since the method of econometrics research on the relationship between input and output was introduced to the evaluation of irrigation water efficiency, it has provided a new perspective for evaluating irrigation water efficiency. This study takes Guizhou in southwest China as an example, using the SFA method to calculate the technical efficiency of food production and irrigation water from 2011 to 2018, and compares the technical efficiency of irrigation water with the measured irrigation water effective utilization coefficient analysis. The analysis shows that: (1) Guizhou’s multi-year average irrigation water technical efficiency value is 0.730, and the difference between cities is large. 20.8% of the urban irrigation water technical efficiency is lower than the average level, and there is a large water saving potential; (2) The correlation coefficient between the irrigation water technical efficiency calculated by the SFA method and the measured irrigation water effective utilization coefficient is 0.804, which is highly positively correlated, and the simulation calculation validity is 70.6%; (3) The SFA method can provide an effective reference for the study of the change trend of the effective utilization coefficient of farmland irrigation water in the absence of measured data.