Assessing the degree of soil erosion in karst mountainous areas by extenics

The ecological environment of karst mountainous areas is fragile, and soil erosion has become an important factor restricting the social and economic development of these regions. How can the degree of soil erosion be scientifically assessed with a reasonable evaluation method? What is effect of the ecological environmental control measures? This study used extenics to assess the degree of soil erosion in karst mountainous areas. The typical karst mountainous area of Guizhou Province was used as the research object. In this study, a soil erosion monitoring indicator system for karst mountainous areas was developed, an evaluation model based on extenics was established, and an index correlation function and comprehensive correlation function were designed to assess the soil erosion of the karst mountainous areas. The key results were as follows. In the soil erosion monitoring index system, the soil nutrient indexes, soil erosion modulus, rock exposure, diversity index, flood season rainfall, population density and natural population growth rate had significant effects on soil erosion in the karst mountainous area. Additionally, we determined the grading standards for soil erosion intensity in typical karst mountains. Finally, the evaluation model was applied to a case study. The status of water and soil conservation was as follows: XW > ML > SB > ZS. These results provide new insights into the evaluation method, namely, extenics, which is helpful for conveniently, quickly and scientifically assessing soil erosion.