Soil erosion prediction in Cilebak – Cirasea Micro Watershed, Indonesia

Abstract

Soil erosion impact on land degradation could threaten soil and water quality. In the mountainous area, soil erosion resulted in losses of topsoil, which containing high nutrients. The study area was located in Cilebak-Cirasea Micro Watershed, Bandung Regency, Indonesia. Landuses in this area were secondary forest (12%), upland agriculture (84%), and paddy field (4%). The objectives of this study were to assess soil erosion and study best management practices (BMP) effect to reduce soil erosion. Universal Soil Loss Equation (USLE) was used to estimate soil erosion with support from Geographic Information System (GIS). USLE parameters, which consist of erosivity, erodibility, slope length, steepness, crop, and soil management, were used to estimate soil erosion. BMP scenarios consist of application raised bed that parallel to contour lines and combination of raised bed that parallel to contour lines and straw mulch addition of 3 and 6 Mg ha−1 year−1. The result indicated that soil erosion rate under current condition was 45.4 Mg ha−1 year−1, which exceeding the tolerable soil loss. All BMP scenarios showed their effectiveness in reducing soil erosion. Proposed BMP to minimize soil erosion rate could probably be able to support government in arranging policies for maintaining or restoring crop productivity for sustainable agriculture.