The spatial and temporal variability and influence factor analysis of soil erosion in a grass farming area: a case study in central China

Abstract

Context Analysing soil erosion has important research significance for the protection of the ecological environment and the prevention and control measures of soil erosion. Methods This paper aims to discuss the soil erosion degree in the warm temperate grass farming subregion of the southern Shanxi and Guanzhong Basin, China, based on Universal Soil Loss Model, RUSLE. Aims The soil erosion modulus from 1998 to 2020 of the study area was calculated and divided into five periods: 2000, 2005, 2010, 2015, and 2020. Key results We highlight two key findings: (1) the average soil erosion modulus changed from 498.86 t km−2 a−1 in 2000 to 316.94 t km−2 a−1 in 2020, and the proportion of soil area with an unchanged erosion degree is above 85%; (2) the average annual erosion area is the largest when rainfall is greater than 550 mm and less than 620 mm. From 2000 to 2020, the area of cultivated land decreased by 3497.47 km2, and the area of grassland increased by 1364.96 km2. The degree of erosion of grassland is the most severe, with soil erosion is most intense when the Normalised Vegetation Index (NDVI) is greater than 0.55 and less than 0.75. Conclusions The results show that the soil erosion in this area is slight on the whole and its degree has been decreasing. Implications The analysis in this paper can elucidate the seriousness of the soil erosion problem so that the government can strengthen the key management of soil and water conservation and achieve the purpose of reducing soil erosion.