基于SRTM DEM的河棚河流域水系提取研究

基于SRTM DEM数据,以河棚河流域为例,利用Arc GIS 10.0中的水文分析模块进行水系的提取试验,分析不同的汇流累积阈值对河网密度、流域面积、河网分级等流域特征参数的影响。结果表明,随着汇流累积阈值的增大,河网密度以及河网总长度都在逐渐减小,并且汇流累积阈值与河网密度之间存在显著的幂函数关系。最后,利用1∶250 000水系图进行对比发现,当汇流累积阈值为200时,利用SRTM DEM提取的河网与实际水系吻合较好。

Study on the Extraction of River Network in Hepeng River Basin Based on SRTM DEM

Based on SRTM DEM data,taking Hepeng River basin as an example,river network was extracted by using hydrological analysis module in ArcGIS 10.0 version.The effects of different accumulated threshold value of confluence on drainage density,drainage area,river network classification and other watershed characteristics parameters were studied.The results showed that drainage density and river network length gradually decreased with the increase of confluence accumulated threshold value.There was a significant power function relationship between confluence accumulated threshold value and drainage density.Finally,the river network data was compared with the 1:250 thousand topographic map and it was found that river network extracted by using SRTM DEM was basically consistent with the actual water system,when the confluence accumulated threshold value was 200.