Assessing spatial distribution of soil erosion in a karst region in southwestern China: A case study in Jinfo Mountains

Abstract

Soil erosion is serious with rocky desertification areas appearing in mountainous Karst regions in southwest China due to a conspicuous contradiction between man and the land resource. Land use and land cover play significant roles in regional soil erosion by water. This paper aimed to quantify regional soil erosion and to explore relationships between soil erosion and land use/land cover in order to locate high risk areas requiring soil conservation. Based on GIS, the Revised Universal Soil Loss Equation (RUSLE) was employed for erosion assessment for a typical Karst region, Jinfo Mountain region in southwest China, using local parameters. Spatial distribution of topsoil erosion was analyzed and relationships between soil erosion and land use/land cover changes (LULC) were statistically explored and discussed for regional erosion control. The overall values were under 25 t.ha.a, with the medium erosion areas accounting for 12.7% and the intense and very intense erosion areas totalled about 6%. The relations between soil erosion and LULC are complicated in this Karst mountainous region. Generally, the amount of ground cover, soil conservation measures, and cultivation disturbance have played critical roles in topsoil loss in the Jinfo mountain region. The reduced ground cover levels accompanying greater cultivation disturbance lead to higher erosion intensity in each landscape, and vice versa.