基于DEM的乌梁素海东部流域河网信息提取

以乌梁素海东部流域为研究区,基于免费获取的3〃的Shuttle Radar Topography Mission(SRTM)数字高程模型(DEM),利用HEC-GeoHMS模块,确定流域不同汇流累积量阈值的河网密度,通过二者关系曲线,得出东部流域最适汇流累积量阈值为15 km2.实现流域水系提取和子流域划分,继而将其与...

Information extraction of drainage network of the eastern basin of Wuliangsuhai Lake based on DEM

Taking the eastern basin of Wuliangsuhai Lake as a study area,drainage network density was determined with different confluence cumulant thresholds by using the HEC-GeoHMS mode based on 3 second of arc Shuttle Radar Topography Mission(SRTM) DEM.The optimal confluence cumulant threshold of 15 km2 was determined by relationship between drainage density and threshold.The extraction of drainage network and subdivision of basins were realized,and it was overlaid with the digital topographic map at 1∶250 000 scale.The results indicated that drainage network and sub-basins extracted from DEM was well consistent with the digital topographic map,that is to say 3 second of arc SRTM DEM could be effectively used for drainage network extraction of the eastern basin of Wuliangsuhai Lake.It could not only save time and energy in topography measurement,but also raise the accuracy of drainage network extraction.