Erosion zoning using EPM model in Golestan province

The main aim of the paper is to determine the erosion hazard using Experimental Model (EPM) in Golestan province. To achieve the aim, the model uses four different effective parameters such as watershed erosion coefficient (Ψ), land use coefficient (Xa), coefficient of rock and soil susceptibility to erosion (Y) and average basin slope (I). According to their importance to erosion, first the variables were classified to different layers and then standardizing operations on the layers were applied in GIS environment. Finally, combined layers were input in EPM and erosion hazard zoning map was produced. The results of the research showed that 57% area of the province is in extreme severe, 14% in severe, 5% moderate, and 24% in very low and low classes. The southern and northeastern parts of the province due to stones with low resistance and high slope are more sensitive to erosion. The results of the research also showed that in the north-west section of the area, despite a high sensitivity of geological formation to erosion, the rate of erosion is considered to be low because of lands with low slop. This case specifies the important of slop in making erosion rather than geological formation in the region.