Spatial Heterogeneity Of The Influence Of Climatic Factors On Agricultural Water Use Efficiency

China is a big country with water for agriculture,but there are serious problems of water scarcity and uneven spatial distribution.The lack of water resources will not only seriously threaten the healthy development of my country’s agriculture,but also affect the national food security.As climate change and its impacts become more and more significant,mitigating the adverse impacts of climate change on agricultural production and agricultural water use is of great significance for improving the ability of rural revitalization to ensure water supply.Existing literature pays attention to many factors affecting agricultural water use efficiency,but few literatures examine the impact of climate factors on agricultural water use efficiency and its spatial differences.This study selects the SBM(Slacks-Based Measure)model of the meta-frontier to calculate the agricultural water use efficiency from 2000 to 2020,and analyzes the regional differences in agricultural water use efficiency;using agricultural water use efficiency as the explained variable,temperature,sunshine,precipitation,humidity As the core explanatory variables,factors such as water resources endowment,agricultural industry structure,water-saving irrigation area,irrigation fees and per capita net income of rural residents are used as control variables.The panel Tobit model and the geographically weighted regression model are used to empirically analyze the influence factors on agricultural water use efficiency.Spatial heterogeneity in the degree of influence with a view to deepening and complementing existing research.conclusion as below:Through the calculation of agricultural water use efficiency in different regions,it is found that:(1)The agricultural water use efficiency under the frontier within the group fluctuates greatly,and it is in a trend of first increase and then decrease.,the southern coast,the northeast,the northwest.(2)Agricultural water use efficiency under the framework of the meta-frontier is in a steady growth trend,with the highest value appearing in 2020.(3)During the inspection period,the gap rate of agricultural water use technology in many provinces is less than 1.In 2020,Beijing and Shanghai will reach the optimal frontier of agricultural water use technology.Through the spatial heterogeneity analysis of the impact of climate factors on agricultural water use efficiency,it is found that:(1)The impact of climate factors on agricultural water use efficiency in different regions is significantly different,and a consistent result cannot be drawn from the national level.The annual sunshine duration has a negative effect on the agricultural water use efficiency in most provinces;the annual average temperature has a positive effect on the agricultural water use efficiency in most provinces;the annual average humidity has a positive effect on the national agricultural water use efficiency;annual precipitation and agricultural water use efficiency negative correlation.(2)From the perspective of endogenous factors,there are significant differences in the sign and size of the estimated coefficients of factors affecting agricultural water use efficiency in different regions.The proportion of agricultural water use and the per capita water resources have a negative impact on agricultural water use efficiency.(3)From the perspective of exogenous factors,the influence of factors such as import and export of agricultural products,irrigation fees,rural per capita net income and expenditure on agriculture,forestry and water affairs on agricultural water use efficiency varies from region to region.Finally,this study proposes strategies to improve agricultural water use efficiency in response to the impacts of climate change.The first is to improve farmers’ awareness of paid water use and their enthusiasm for water conservation,and to promote the efficient use of agricultural water resources;the second is to reduce the losses and adaptation costs caused by climate change,and to explore long-term mechanisms for adapting to climate change;the third is to improve farmland such as water-saving irrigation Water conservancy facilities to improve government supervision and governance of agricultural water use.