出版社：geodynamics Research International Bulletin Online
摘要：An algorithm for removing unreasonable closed depressions from raster Digital Elevation Models (DEM’s) is proposed. This algorithm is based on the basic feature points (entrance, nadir and outlet) of topographic depressions and a directional erosion mechanism. The main process is a pixel-by-pixel elevation-reducing method that allows water to flow and erode obstacles iteratively from a depression entrance to a depression nadir, and then to a depression outlet. Therefore, unreasonable closed depressions can be removed from DEM’s without the need of any other auxiliary information. We applied the method to some real areas in the Yangtze and Yellow River watersheds and the results demonstrate that our approach can keep more original DEM information in depression areas than the traditional filling idea, thus it provides a better method to extract more accurate drainage lines in topographic depressions.
