Statistical Soil Erosion Model for Burnt Mountain Areas in Korea—RUSLE Approach

The objective of this paper is to develop a model to estimate soil erosion based on data from natural rainstorms on the hillslopes of burnt mountains. For this research, 52 plots were established on mountain slopes in the eastern coastal region of South Korea and operated for 6 years after the fire. Runoff and soil erosion were influenced greatly by rainfall and vegetation factors, respectively. The vegetation index that reflects the structure of vegetation recovered after the forest fire and the soil index that reflects soil characteristics in burnt forest lands showed higher correlations than factors of the revised universal soil loss equation (RUSLE). Sediment yield decreased generally with increasing slope steepness and length because of the effects of depression storage and flow interception by stems and litter on forest lands. The Soil Erosion Model for Mountain Areas in Korea (SEMMA), used to compute sediment yield from hillslopes, is a statistical model composed of four variables: rainfall, vegetation cover, soil, and topography. According to sensitivity analysis for each parameter, rainfall and vegetation showed high sensitivities. The SEMMA model was improved by developing several equations that were classified by rainfall depth and vegetation coverage. This model may be applied usefully to assess soil erosion risks in burnt mountains.