Several Problems and Their Solutions in DEM-based Automatic Drainage Network Extraction

In this paper,a new solution for data conditioning procedures in surface runoff model is proposed after comparing several automatic extracting approaches based on DEM.According to current DEM resolution,depressions and flat areas in a DEM are mainly from real landform features and spurious features.Spurious depressions can arise from elevation overestimate or underestimate,and flow direction in flat areas is a kind of convergent flow pattern that will be directed not only towards lower elevation but also away from higher elevation in inlet-outlet direction.An experiment in ARC/INFO produces better drainage network.