Soil erosion evolution and spatial correlation analysis in a typical karst geomorphology, using RUSLE with GIS
Cheng Zeng1,2,3, Shijie Wang1,3, Xiaoyong Bai1,3, Yangbing Li2, Yichao Tian1,3, Yue Li4, Luhua Wu1,3, and Guangjie Luo3,51State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, 99 Lincheng West Road, Guiyang 550081, Guizhou Province, PR China 2School of Geography and Environmental Sciences, Guizhou Normal University, Guiyang 550001, China 3Puding Karst Ecosystem Observation and Researcj Station, Chinese Academy of Sciences, Puding 562100, Guizhou Province, PR China 4Beijing Forestry University, Key Laboratory of State Forestry Administration on Soil and Water Conservation, Beijing, 100083, China 5Institute of Agricultural Ecology and Rural development, Guizhou Normal College, Guiyang 550018, China
Received: 06 Jan 2017 – Accepted for review: 09 Jan 2017 – Discussion started: 16 Jan 2017
Abstract. In spite of previous studies on soil erosion in Karst landform, limited data are available regarding the spatial and temporal evolution and the correlation of spatial elements of soil erosion in Karst. The lack of this study leads to misassessment of environmental effects on the region especially in the mountainous area of Wuling in China. Soil erosion and rocky desertification in this area influence the survival and development of 0.22 billion people. For this reason, the typical Karst area in South China is the object of this study. This paper aims to analyze the spatial and temporal evolution characteristics of soil erosion and investigate the relationship between soil erosion and rocky desertification by using GIS technology and modified universal soil loss equation (RUSLE) model to reveal the relationship between soil erosion and major natural elements in this area. (1) In 2000–2013, the proportion of the area of micro- and slight erosion increases, whereas the proportion of the area of moderate erosion and above decreases. Erosion of moderate and above levels changes into micro- and slight erosion. (2) The soil erosion area in slope zones at 15°–35° accounts for 60.59 % of the total erosion area and 40.44 % of total erosion. (3) The amplitude reduction in the annual erosion rate is higher in the Karst area than that in the non-Karst area. Soil erosion in different outcrop areas of rock generally shows an improving trend, but the dynamic changes in soil erosion significantly differ among various lithological distribution belts. (4) The soil erosion rate of rocky desertification area with moderate and below levels of erosion decreases, whereas the erosion rate of rocky desertification area with severe erosion level increases. Results show the gradual decrease in the temporal and spatial variation of soil erosion in the study area. Lithology is the geological basis of soil erosion. Changes in the spatial distribution of lithology and rocky desertification induce high soil loss. The area is characterized by high rocky desertification, low erosion module, and decreasing annual erosion rate.
Zeng, C., Wang, S., Bai, X., Li, Y., Tian, Y., Li, Y., Wu, L., and Luo, G.: Soil erosion evolution and spatial correlation analysis in a typical karst geomorphology, using RUSLE with GIS, Solid Earth Discuss., doi:10.5194/se-2017-1, in review, 2017.