Assessment of soil erosion in the Ihsaniye watershed area, Afyonkarahisar, Turkey

Abstract

This article discusses research in which the authors apply the Universal Soil Loss Equation (USLE), Geographical Information Systems (GIS) and Remote Sensing (RS) to the mapping of the soil erosion risk in the Ihsaniye watershed, Afyonkarahisar, Turkey. The rainfall-runoff erosivity (R) factor was developed from annual precipitation data and from previous studies. Soil maps and soil survey data were used to develop the soil erodibility factor (K), and a digital elevation model was used to generate the topographic factor (LS). The cover-management factor (C) was obtained from Landsat TM image. A soil erosion risk map with five classes was produced. Almost half of the watershed area falls within the low (63%) and slight erosion categories (8%), and is mostly seen in the southern section. The low and slight erosion risk areas are situated in flat plain and low slope areas. Only 18% of the watershed suffers from high and severe erosion risks in the north-east and the south-west. The results can be used to advise local government with regard to prioritizing the areas requiring immediate erosion mitigation. This research implies that GIS and RS provide promising tools for evaluating and mapping soil erosion risk in the study area. Key words: Ihsaniye, Afyonkarahisar, universal soil loss equation (USLE), geographical information systems (GIS), soil erosion risk.