Research On Spatiotemporal Evolution And Driving Mechanism Of Non-grain Production Of Cultivated Land In Guanzhong Plain

As a populous country,China has always attached great importance to the protection of arable land and food security.Cultivated land is an important guarantee of food security.The Chinese government has issued a series of policies on cultivated land protection to ensure food supply.However,there are obvious non-grain phenomenon in some areas of cultivated land,which affects the grain planting area and brings great pressure on grain production.This causes the contradiction between food supply and demand to be prominent.However,there are few researches on the non-grain conversion of large area of cultivated land at present,and the driving mechanism still needs to be further discussed.This study takes the Guanzhong Plain as the study area.ENVI and Arc GIS were used to obtain non-grain production of cultivated land by constructing extraction.Terefore,the temporal evolution,spatial evolution and characteristics of spatio-temporal evolution of non-grain production of cultivated land were analyzed from 2002 to 2017.Furthermore,an index system was constructed,and the driving mechanism of non-grain production of cultivated land in 2002,2007,2012 and 2017 was analyzed by using multiple linear regression,spatial autoregressive model and geographically weighted regression.The research shows:(1)From the perspective of time evolution,non-grain production of cultivated land showed an overall upward trend from 2002 to 2017,with a net increase of 2.69598 million hectares,and the proportion of non-grain production of cultivated land increased from 31.143% to 47.383%.(2)From the perspective of spatial evolution,the non-grain production of cultivated land was gradually widespread in the Guanzhong Plain,and spread rapidly in the southern region.(3)From the perspective of time and space,the global Moran index was significantly positive in different years,but there was a downward trend.The phenomenon of spatial agglomeration decreased,and non-grain production of cultivated land was more common.The characteristics of local spatial agglomeration were different in different years.(4)From the multiple regression results,the influence of precipitation on the non-grain production of cultivated land was significantly negative in2002,2007,2012 and 2017.The influence of temperature on the non-grain production of cultivated land was significantly negative in 2012 and significantly positive in 2012.The influence of slope on the non-grain production of cultivated land was significantly negative in 2002 and significantly positive in 2012 and 2017.The influences of elevation and traffic distance on the non-grain production of cultivated land were significantly positive in 2002,2007,2012 and 2017.(5)From the geographically weighted regression results,the low-value areas where the precipitation factor has an impact on the the non-grain production of cultivated land were mainly in the northeastern region,and the high-value areas were mainly in the southwestern region.The range where temperature has a positive impact on the non-grain production of cultivated land gradually expanded,and the high-value area changed from the southwestern region to the southeastern region.The influence of slope on the non-grain production of cultivated land was higher in the western region than in other regions,the areas of low value were mainly located in the southeast.The influence of elevation on the non-grain production of cultivated land was greatest in the eastern and southern regions.Traffic distance has a greater impact in the west as well as in the south,the areas of low values were mainly in the northeast..The market distance has the greatest positive impact on the non-grain production of cultivated land in the northeastern region,but the range of regions with negative regression coefficients was gradually expanding.Based on the above analysis results,this study puts forward policy recommendations from the perspective of balancing economic crops and food security,and provides a certain reference value for the research on the current situation and driving mechanism of non-grain production of cultivated land.