数字流域河网提取中的阈值问题研究

Application and Study of Extracting Digital Stream Network from Elevation Model

基于DEM提取数字河网是一种高效率获取河网信息的方法,D8算法由于直观简单,成为数字河网提取中应用最为广泛的模型之一.本文采用这一模型对南川市的河网进行了模拟,并同实际河网进行了对比分析.研究结果表明,汇流面积阈值设定的大小与生成河流总长度存在着幂指数函数关系,通过相关性分析恰当选择阈值,可使生成的河网与实际河网更加相符,也保证了模拟结果的准确性.

It is a highly efficient method to acquire the information of stream network from DEM by using the arithmetic of D8, which is one of the most widely used models in extracting digital network. This article has simulated the stream network of Nanchuan city by using this model, and compared it with the actual river network. The study shows that exploring a method of simulate digital network by correlation analysis of choosing an appropriate threshold will make the generated network match up to the actual river much better. Meanwhile, the veracity of simulation results has also been ensured.