GIS支持下基于DEM的中等流域的划分——以富县为例

Watershed Division based on DEM in GIS

以陕西富县为例,探讨在GIS环境下从数字高程模型(DEM)中提取流域特征并进行中等流域的划分的详细过程,包括DEM的预处理、流水方向的确定、汇流累积量分析、河网的提取和子流域的划分,通过设定不同的汇流累积量的阈值,通过实验,富县地区的阈值设为20 000,得到中等流域的划分结果较为合理。

As an example of Fu county in Shaanxi province,the article discusses which extract the basin's the characteristics from digital elevation model(DEM) and have a detailed process how to divide the secondary river GIS environment,including the pretreatment,water DEM direction determination,the confluence collection analysis and river extraction and different division of the basin.The article is based on setting the confluence collection threshold and through experiments,the threshold in Fu county district is set to 20,000,a medium basin partitioning results received is more reasonable.