Abstract: Based on the statistical data of cultivated land resources and grain production of China's provinces from 2009 to 2017, the center of gravity of cultivated land area and the center of grain yield in China from 2009 to 2017 were obtained by constructing the center of gravity model and grain sensitivity model, and the grain sensitivity of each province was obtained. ArcGIS 10.2 software was used to realize the spatial expression of the result data. The results showed that,the cultivated land area in China generally showed a decreasing trend. To be specific, the cultivated land area in eastern regions continued to decrease while the cultivated land area in western regions increased in fluctuation; The grain yield showed an increasing trend, the grain yield in northern regions increased year by year while the grain yield in southern regions decreased; The cultivated land area center of gravity was moving from west to north, while the grain yield center of gravity was moving from north to east. The annual fluctuation about the movement distance of the former was less than that of the latter; On the whole, the sensitivity between grain and cultivated land showed a declining trend across the country. Provinces with higher degrees of sensitivity between grain and cultivated land were mainly distributed in areas where the natural conditions were relatively poor or the cultivated land systems were fragile. At the same time, it tended to transfer to central China and some economically developed provinces. Therefore, it was necessary to adjust agricultural policies in time to better protect cultivated land resources and food security.

Key words: cultivated land area, grain yield, center of gravity movement, sensitivity between grain and cultivated land, temporal and spatial variation