Spatial characteristics of the human factors of soil erosion at the boundary of political divisions: A spatial approach

Soil erosion leads to the loss of soil fertility, the destruction of surface soil structure, and the loss of land resources, posing serious threats to the ecological environment, food security, and sustainable development. A series of mature soil erosion research theories is available at present, but only a few studies have dealt with the correlation of soil erosion and its influencing factors in a cross section, and research on soil erosion is limited to the interior of regional boundaries. This study aims to introduce a spatial econometric model into the study of soil erosion to explore the spatial characteristics of the human factors of soil erosion at the boundary of political divisions by using 30 provincial administrative regions in China as examples. First, Moran's I index is used to test the spatial correlation of regional soil erosion as the premise for exploring the characteristics of soil erosion influencing factors. Second, an entire spatial data model is established to analyze the overall spatial characteristics of human factors. Lastly, six conditional spatial models are developed to examine the spatial characteristics of human factors in different subperiods, subregions, and spatial weight matrices (SWMs). The following results are obtained. (1) Regional soil erosion exhibits significant spatial correlation and demonstrates high-high and low-low aggregation characteristics. (2) The human factors of soil erosion, such as population, economy, land use type, and soil and water conservation, exert significant spatial spillover effects that will cross the boundary of political divisions and affect the soil erosion status of adjacent regions. (3) The spatial spillover effects of human factors vary due to different periods, regional development statuses, and SWMs. In conclusion, this study confirms that regional soil erosion exhibits significant spatial characteristics and the human factors of soil erosion exert spatial spillover effects on the boundary of political divisions. In estimating soil erosion, its spatial characteristics and the spatial spillover effects of its influencing factors should be considered to obtain accurate estimation results.