Drainage Network Analysis, Comparis of Digital Elevation Model(DEM) from ASTER with High Resolution Satellite Image and Areal Photographs

Abstract

Digital Elevation Model (DEM) data have been used to derive hydrological features, which serve as inputs to various models. Currently, elevation data are available from several Major sources and at different spatial resolutions. This paper shows the quality and accuracy of drainage network analysis resulted from ASTER DEMs. Hydrology toolsets in the when we used the vector datasets for Analyzing in separate land features. The agreement degree between two layers is very low for spatial pattern, river frequency and drainage density in lowland areas. ArcGIS package was used to extract drainage networks from a grid DEM for cheshmehkhan catchment in the northeastern of Iran. We have compared the Extracted networks from DEM (DEM layer) with the one derived from aerial photographs and high resolution satellite Images as real ground (Geo layer). Results showed both the DEMs and current GIS algorithms have basic imperfections. However, the drainage morphometry results based on extracted rivers from DEM are similar of Natural network in the raster format and for whole catchment area but there are many large differences.