基于数字高程模型的河网提取及子流域生成

Drainage network extraction and subcatchment delineation based on digital elevation model

提出新的从DEM直接提取河网与划分子流域的方法(AEDNM)。该方法与以往方法的不同之处在于不再对DEM进行填洼处理,而是结合图论与水文学的思想,从流域的出口直接向上游搜索,通过图的遍历来确定流向,使全流域形成一个有向无环图,这样提取的河网可以保证是连续的,同实际河网误差很小。根据河网划分的子流域大小也基本均匀,能够满足水文模型模拟的需求。经过黄河、泾河与白河流域的算例验证,表明该法简单可行。

An automatic extraction method for drainage network is proposed. This method differs from the traditional methods in the approach of dealing with the sink-filling problem. It determines the flow direction by searching upward from the catchment outlet and form a directed but non-loop graph based on the idea of combining the graphic theory with hydrology. The proposed method guarantee that the generated river network is continuous and the sizes of the delineated subcatchments are homogeneous. The examples of application indicate that this method is simple and practical.