Extracting River Networks of Lianyungang City from SRTM Data

This article used SRTM data to extract the river networks in Lianyungang of China. Because of the defect of SRTM data, the data must be filled first. Through the filled data to extract DEM and then to obtain river networks. Different algorithm would get the river networks with different resolutions, so this article made a set of data processing methods to ensure the precision. Selecting different CSA thresholds would obtain differently detailed river networks. The analysis showed that the selection of CAS threshold is very important and will influence the statistic characteristics of whole basin river networks directly. The algorithm could simulate the real water system in the area with topographic relief. In contrast to the area with flat terrain, for example in Lianyungang, the algorithm will cause distinctive errors.