The extraction of watershed characteristics of the Source Area of Yellow River based on SRTM DEM with ArcGIS

The principles and procedures for extracting the watershed characteristics using the Shuttle Radar Togograhy Mission (SRTM) Digital Elevation Model (DEM) data in ArcGIS9.3 was introduced in this paper, and its application in the Source Area of Yellow River (SAYR) was used as a case analysis. Much emphasis was put on the details of watershed generation, such as filling the depression of SRTM DEM data, extracting flow directions, determining flow accumulation, generating and classifying river networks, generating watershed and dividing sub-watersheds, as well as operating all them with SRTM DEM in the ArcGIS 9.3 environment. The results then were compared with those existing empirical coarse region maps of the SAYR from documentations and literatures. This method resulted higher efficiency and precision for watershed characteristics extraction in ArcGIS, and avoided some artificial errors. Additionally, it is labor saving and less time-consuming. The generation of watershed characteristics lays foundations for quantitative analysis on further studies in alpine ecology, geological environments, and hence facilitates modeling and mapping of permafrost in the SAYR.