Study On Soil Erosion Based On GIS/RS In Qitai County

Soil erosion is one of the main environmental problems in the world ,it is the root cause of land deterioration , soil fertility degression, soil physico -chemical quality bad, land use capability felling and ecological environment deterioration.In this thesis ,took qitai County as the region of interest, according to landsat TM satellite images and digital maps etc ,based on remote sensing, geographic information systems and tradition theoretics ,the author disscussed the method of speedy monitoring and evaluation on the changes of soil erosion ,searching an approach of celerity surveying soil erosion by remote sensing and geographic information systems .The research result could help the decision making for further water and soil conservation work ,and it also offers reference for monitoring, evaluating and forecasting soil erosion.In this thesis , firstly, TM remote sensing images were geometry rectified , image intensification, mosaic and cropping by using remote sensing image software ENVI, selected computer-aided supervised classification means to cany distribution using TM remote sensing images of qitai County ,and incorporated soil category material to achieve underlaying surface parameter and vegetation cover degree information in the region of interest .Then ,by Arc GIS9.0, established digital elevation model(DEM)of qitai County ,and use DEM to analyze and achieve terrain feature, use for reference soil erosion model which based on GIS both here and abroad ,on the foundation of analyzing soil erosion influencing factors in this region, built currency soil erosion model based on GIS. Finally, put up soil erosion and influencing factor statistical analysis by Arc GIS software. Create and output soil erosion thematic map.This thesis discuss and research substantively the technology and means extractive correlation factor of soil erosion ,it is shown that it will distill correlated factor information speedily and effectively by "3S"technology,this method is more sciencific and nice ,and holding accurately change trend of soil erosion from macroscopic view.