8. Applying GIS technology and open data on the internet to assess the risk of soil erosion using the RUSLE model in the Tra Khuc river basin

Abstract

Soil erosion caused by rainfall is the most important form of land degradation in many parts of the world, including in Vietnam. The Tra Khuc river basin, located in the central provinces of Vietnam, is one of the most erosion-prone areas due to complex topography and high rainfall intensity. Therefore, this study used the Revised Universal Soil Loss Equation (RUSLE) model along with the application of Geographic Information System (GIS) technology and open-source internet data to map the soil erosion severity and assess erosion risk in the Trà Khúc River Basin. Input parameters included rainfall data, land cover, remote sensing imagery, Digital Elevation Model (DEM), and soil type. The results indicated that the average annual soil loss in the basin was 12.67 tons/ha/year, exceeding the tolerable soil erosion threshold. Specifically, 40.6 % of the total area (247,427.9 ha) experienced soil loss of less than 1 ton/ha/year, while 9.17 % (55,837.5 ha) suffered from very high erosion rates (>50 tons/ha/year), necessitating urgent mitigation measures. The study also shows that integrating open-access data with the GIS-based RUSLE model is a feasible approach for estimating soil erosion in the study area. This method enables a focus on reducing land degradation solutions to prevent further land degradation and support sustainable development in the future.