Intergrated Remote Sensing and GIS Based Watershed Erosion Study in Zagros Fold Belt, Iran

要旨

Quantitative analysis of morphometric parameters such as stream length, drainage density (DD), bifurcation ratio (Rb), slope, shape factors are good indicators for morphological evolution of a basin. Relationships of these parameters with structure, lithology and geomorphology are enhancing the factors which control the erosion behavior of the area and further use for proper management and development programs. In this study LANDSAT ETM+ data is used for DIP techniques such as NDVI and lineaments enhancement, and GIS techniques to extract different models. In this study the Dashtgol basin which is a watershed overlooking the reservoir of the great Shahid Abasspour dam in the south west Iran has selected to evaluate geomorphic factors. This basin is located within the ZFB. It exhibits complex geological and geomorphic configuration. The information from remotely sensed and ground truth data are analysed in GIS environment. Further, the study area is divided in 10 hydrologic divisions. The results show that the maximum erosion belongs to the sixth hydrologic division (27.5 t/h per year) and the minimum erosion belongs to second hydrologic division (14.8 t/h per year). Geologic interpretation and geomorphic analysis in GIS environment on the Sabzab river profile shows that the tectonic process is a factor to increase the rates of sedimentation and erosion in the study area.