The Investigation of Some Data Layers Integration for Water-Soil Erosion Features Intensity Map in Mountainous Regions (Case Study: Kan and Sologhan Basin)

With regards to the importance of soil erosion features map in watershedmanagement, and also country extent, diversity of climate, physiographic, geology, pedology, land use and plant cover, it is expectable the high difference with due attention to soil erosion types that is caused in different conditions differentiate to investigate erosion features. For investigating some method in providing erosion types map at the scales 1:250000 in mountainous regions, a study was conducted in Kan-Sologhan basin, north-west Tehran, Iran. At the first stage, from integration of data layers, four working units maps were prepared including: 1. geology, plant cover and slope, 2. geology, land use, slope, 3. rocks erodibility, land use and slope and 4. rocks erodibility, land use and land units. At the second phase, intensities of soil erosion types in 53 ground control points were controlled and accurate positions were registered by GPS. Each of working units map was overlayed by ground control points map. Results indicated that maps 1, 2 and approximately map 3, are no suitable methods for differentiating homogenous units, because the high numbers of working units beside together have same erosion features. It should be regarded that the high numbers of units from an economic regards were caused the high costs and time consuming. Map 4 including 6 units that two units, 66.6% and one unit, 85% of ground control points had same erosion. In other units including agriculture lands and rocks outcrops, approximately, erosion features were uniform in all points. In general, integration of land use, rocks erodibility and land units layers is the better method than other methods for providing soil erosion features map.