Abstract:

Exploring the degree of coupling and coordination of agricultural soil and water resources in different regions is of great significance to optimizing the allocation of agricultural soil and water resources and promoting the transformation and development of agricultural production patterns. Based on the data of 117 county-level agricultural land and water resources in Shanxi province, a regional index system was established with reference to previous studies, and methods such as geographic grid, principal component analysis, cluster analysis, and geodetector were used to study the current status of agricultural soil and water resources utilization and dominant factors in Shanxi in-depth. The results showed that Shanxi agricultural soil and water resources could be divided into 4 first-level regions (Region A, Region B, Region C, and Region D) from good to worse, and each first-level region was subdivided into 3 sub-regions, which could be divided into 12 sub-regions in total. The overall difference between the first-level regions was significant: Region A had superior water and heat conditions and better utilization of soil and water resources (arable land index and water resources index of 0.39 and 0.98, respectively, were the best in the four first-level areas), which was mainly distributed in Yuncheng basin in the southwestern part of Shanxi. Region B had good water and heat conditions and higher utilization rate of water resources, but with average utilization of cultivated land, which wa mainly distributed in Fen river basin in the central part of Shanxi, the Yellow river in the western part of Shanxi and Qin river basin in the southeastern part of Shanxi. Region C had better hydrothermal conditions and good utilization of water resources, but relatively poor utilization of arable land, which was mainly located in the Lvliang mountain system and Taihang mountain. Region D had more general hydrothermal conditions and soil and water resource utilization, and was mainly located in northwestern and north of Shanxi. In terms of sub-region division, the three sub-regions in Region A had balanced distribution of soil and water resources, small differences, concentrated distribution, and balanced region share. Region B was dominated by the sub-region with adequate agricultural water utilization, and its distribution was more concentrated. Region C was dominated by the sub-region of insufficient agricultural water utilization and its contiguous distribution, and the other two sub-regions were small in region and dispersed. Region D was dominated by the sub-region of upgraded agricultural water irrigation, but its distribution was more scattered. Changes in the soil and water resources system in Shanxi were mainly driven by natural factors, and the influences were, in descending order, the water resources index (0.4961), the proportion of water used in agriculture (0.4815), the annual average temperature (0.4480), the irrigation rate of cultivated land (0.4387), and the effective cumulative temperature ≥10℃ (0.4190), among which the interactions of the average annual temperature and the irrigation rate of arable land were the most significant. The results of this study can provide a reference for optimizing the agricultural planting structure in Shanxi.

Key words: Agricultural zoning, Geographic grid, Cluster analysis, Geographic detector