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

Subject Areas : Urban and Regional Planning Studies

Ali Mohammadi Torkashvand ¹ ( استادیار دانشگاه آزاد اسلامی واحد رشت )

Received: 2006-05-17 Accepted : 2007-03-16 Published : 2007-02-20

Keywords: Map, Erosion Features, Geographical information system(GIS),

Abstract :

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 highdifference with due attention to soil erosion types that is caused indifferent conditions differentiate to investigate erosion features. Forinvestigating some method in providing erosion types map at the scales1:250000 in mountainous regions, a study was conducted in Kan-Sologhanbasin, north-west Tehran, Iran. At the first stage, from integration of datalayers, four working units maps were prepared including: 1. geology, plantcover and slope, 2. geology, land use, slope, 3. rocks erodibility, land useand slope and 4. rocks erodibility, land use and land units. At the secondphase, intensities of soil erosion types in 53 ground control points werecontrolled and accurate positions were registered by GPS. Each ofworking units map was overlayed by ground control points map. Resultsindicated that maps 1, 2 and approximately map 3, are no suitable methodsfor differentiating homogenous units, because the high numbers ofworking units beside together have same erosion features. It should beregarded that the high numbers of units from an economic regards werecaused the high costs and time consuming. Map 4 including 6 units thattwo units, 66.6% and one unit, 85% of ground control points had sameerosion. 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 bettermethod than other methods for providing soil erosion features map.