Prioritizing areas for watershed management activities by preparing soil erosion intensity map (Case study: Safaroud River watershed, Northern Iran)

An awareness of the state of erosion in watersheds seems to be necessary for planning and prioritizing management and conservation activities. The purpose of the present study is to prioritize areas for watershed conservation and management activities by preparing a soil erosion intensity map using a geomorphological model and the AHP technique in the Safaroud River watershed, which is located in Mazandaran Province, Northern Iran. So, criteria in the geomorphological model, such as physiographic, climatic, geological, vegetation and land use criteria were used for the erosion intensity mapping. The studied criteria were weighted using the AHP technique. The erosion facies map was prepared, and the weight of each facies for erosion incidence was calculated. By combining the raster map of each criteria weight with the raster map of the facies weight together in GIS, the raster map of erosion intensity was prepared. The results showed that the land use criterion exhibited the minimum weight (0.045), while the climatic and geological criteria the maximum (0.209). By preparing the homogeneous unit map and calculating the weighted average of the erosion intensity in each homogeneous unit, it was determined that homogeneous units No. 17, 28, 39, 29 and 14 with erosion intensity coefficients of 0.0848, 0.0663, 0.0585, 0.0571 and 0.0476, and a total area of 341.94 hectares had the highest erosion intensity in the area. Hence, these homogeneous units are prioritized for protection and management plans.