Erosion Risk Modelling Using Geographic Information System in Beringin Watershed, Semarang City

One of the main environmental problems that can have an impact on natural, agricultural and environmental resources is soil erosion. During the last years there has been a growing awareness of the importance of problems directly related to erosion in almost Indonesian watershed region. Beringin Watershed is a watershed that became the center of the hydrological cycle in Ngaliyan and Mijen districts. Approach in watershed management is related to erosion threat that can be done by doing in handling and management of watershed. Management of soil conservation, erosion control and management of water catchment areas can be presented in geospatial information that contains spatial information and quantitative data from information on soil erosion. In this study, the risk map model of erosion in Beringin watershed mainly based in expert's knowledge (AHP) and the RUSLE model which is considered to be a contemporary simple and widely used approach of soil erosion assessment. The risk mapping resulted in high class threatening 1.309%, medium grade 48.183%, and 50.508% of the total area of Beringin Watershed. The high-risk areas are located in Subdistrict of Beringin, Kedungpane, Pesantren, and Ngaliyan.