Estimation of soil loss using the USLE model and GIS tools in the Chillón river basin, Lima, Peru

Abstract

Poor land planning, where the potential and limitations of land use are not considered in planning and spatial organization, has in recent years become one of the main sources of environmental degradation. This research presents a diagnosis and estimation of water erosion in the Chillón river
basin, applying the Universal Soil Loss Equation (USLE) mathematical model, and analysis employing Geographic Information System (GIS) tools, in order to understand the geospatial behavior of this phenomenon. The USLE factors considered for this research include rainfall erosivity (R), soil erodibility (K), the topographic factor (LS), the conservation factor and human management (C and P). A spatial database was built containing rainfall information from 14 weather stations, data extracted from the 1:125 000 soil map «Land Use Plan for the Chillón River Basin», the ASTER Global Digital Elevation Map (GDEM), current land use in the area, the interpretation of satellite imagery, IGN mapping, and geo-referenced information collected through fieldwork. The processing of spatial information was made using GIS, which enabled the superimposing of erosion factors and potential erosion behavior in the Chillón river basin.