河道烧录算法提取出断裂河网的必要条件探究

河道烧录算法是比较常用的基于实际河网修正提取模拟河网的方法。该方法能有效地提取出同实际河网高相似度的模拟河网。然而,在某些情况下,所提取的河网会产生"断裂"现象。深入研究发现,出现"断裂"的必要条件是:(1)实际河网栅格中存在全局高估栅格;(2)实际河网源头栅格正好位于DEM有效数据边界上。在实际应用中,只要消除两个条件中的任何一个,即可有效地避免提取出"断裂"的模拟河网。

Study on necessary conditions for extracting phenomenon of disconnection with stream burning method

The stream burning method is a more conventional way to extract the simulated river network from DEM based on the modification of the actual river information. The method can effectively extract the simulated river network that has a high similarity with the actual one. However，the phenomenon of disconnection of the extracted river network is to occur in some instances. Through a deep study，the necessary conditions for the disconnection are found out that：（1）some globally over-estimated grids are there within the actual ones；（2）the grid of the source of the river network is just located at the edge of the effective DEM data. In the actual application，just only eliminating one of both the conditions，the extraction of the disconnected simulated river network can be effectively avoided.