Investigation of soil erosion risk in Doab basin of Lorestan by network analysis and RS and GIS techniques

The erosion is one of the waster factors of land sources. Understanding of erosion danger provides possibility of identifying critical regions and priority of administrative and protective plans. The aim of this research is providing of soil Endanger map by GIS, RS and multi criteria division systems in Doab basin of Lorestan province. For purpose, data of 8 important factors in soil erosion including: slope aspect, slope, lithology, land use, vegetation cover, precipitation, soil was provided by GIS. Then weight of each factor and weight of classes each layer was calculated in super division by Analytic network process and pair comparison methods. Then, case study was classified for each factor by GIS overlaying functions. Finally, final map was provided in 5 classes of very much danger, much danger, middle danger, low danger, and very low danger by classified maps combination based on obtained weight from Analytic network process method. Results indicated that%11, %13, %16, %28, and%32 of case study are very much danger, much danger, middle danger, low danger, and very low danger respectively. Also, for results validity, position of 93 points of erosion was determined in field investigation with GPS. Then, these points compared with erosion map by ArcGIS overlaying functions. Results of this overlay indicated that from these points, %24, %51, %13, 3 and 9 point has laid in very much danger, much danger, middle danger, low danger and very low danger respectively. So Data obtained during the field study is accordance with ANP method results that are indicator precision of Analytic network process method in investigation of erosion.