Research on application of digital river network extraction algorithm based on DEM

Extracting the hydrological terrain parameters based on DEM is the foundation of integrated application of hydrological model and GIS.Using the technologies of depressions filling,elevation increasing and D8 algorithm,combining with the automatic extraction method of river network catchment area based on DEM,multiple thresholds are selected and compared to finish the application study of the Min and Tuo rivers' extraction.The results show that the extracted river network is close to the actual river and the method is highly automatic.The method has certain value in the analysis of river network structure.The extraction result can be a reference for the digital river network modeling in the application of three-dimensional GIS.