基于Hydrology的山区1:1万DEM水系提取研究

Research on Water System Extraction of 1:10,000 DEM in Mountain Areas Based on Hydrology

利用重庆市万州区4幅比例尺为1∶1万,地面分辨率为5 m的DEM数据,根据地表径流模型原理,通过ArcGIS中的HydrologyTools模块进行D8算法提取流域水系,计算汇流累积量,并最终生成河网。结果表明:对1∶1万DEM进行水系提取,最小水道集水面积阈值设定为50 000个栅格较合理;对于山地地形,基于1∶1万DEM数据,利用ArcGIS Hydrology模块提取河网的方法,从提取的效率和结果的精度两方面看来都是切实可行的。

DEM data of Chongqing Wanzhou District from four maps of 1：10,000 scale and 5m surface resolution are used to extract watershed network by D8 algorithm through HydrologyTools module in ArcGIS and according to surface runoff model principle and to calculate confluence accumulation amount in order to ultimately create a river network.The results show that it is relatively reasonable to set 50,000 grids as minimal flow accumulation water area threshold value for water system extraction of 1：10,000 DEM and that the accuracy of extracting efficiency and results by applying ArcGIS Hydrology module to extracting river network is feasible for mountainous area and based on 1：10,000 DEM data.