Analysis on agricultural water and soil resources matching coefficient, carrying capacity and influencing factors in main grain production area

In order to objectively analyze the matching status of agricultural water and soil resources in the main grain production areas, and correctly understand the carrying capacity level and main influencing factors, we calculated the matching coefficient of agricultural water and soil resources according to the data of water resources and cultivated land resources.Meanwhile, the evaluation index system of agricultural water and soil resources carrying capacity in the main grain production areas was constructed from the four systems of agricultural water and soil resources, society, economy and ecology.Based on the TOPSIS model and obstacle degree model with combined weighting, the change characteristics and influencing factors of agricultural water and soil resources carrying capacity in main grain production areas from 2011 to 2018 were quantitatively studied.The results showed that the matching coefficient of agricultural water and soil resources in the main grain production areas was 6 097 m3/hm2 to 8 878 m3/hm2,indicating the matching degree as a whole needs to be improved, and presented a spatial matching pattern of “the central region was the lowest, the northern region was slightly lower, and the southern region was the highest”.The carrying capacity of agricultural water and soil resources in main grain production areas as a whole showed a slight decreasing trend at a rate of 0.005/10 a, and showed a spatial distribution characteristics of “the central region was the lowest, the southern region was medium, and the northern region was the highest”.The four systems have the similar impact intensity on the carrying capacity of agricultural water and soil resources in the main grain production areas, and the matching coefficient of agricultural water and soil resources, per capita cultivated land area, per capita grain yield, ecological environmental water use rate and per capita water resources in the system are the strongest obstacle factors affecting the carrying capacity of agricultural water and soil resources.