分水线、汇水线的多分辨率多阈值提取分析

Extraction Analysis of Dividing Waterline and Collection Waterline by Multi-resolution and Multi-threshold Values

分水线、汇水线是水文信息的基础要素,其提取的方法有很多种。选择其中最为方便实用的一种作为研究方法,以四川省泸定县为研究区域,将DEM分辨率和平面曲率的阈值作为提取过程中的不确定性因素,通过分析不同分辨率DEM数据在设置不同平面曲率阈值情况下生成的分水线、汇水线的线密度的差异变化,从而体现出两者大小对分水线、汇水线提取的影响,为该地区水文参数的准确获取提供依据。

Dividing waterline and collection waterline are two basic elements of hydrological information. A lot of methods could be used to extract dividing waterline and collection waterline. One is chosen to study on the ground of its convenience and practicality. And Luding County, Sichuan Province is taken as a study area. The resolution of DEM and the threshold values of plane curvature are considered as uncertain factors in the extraction process. The differences and changes of linear density of dividing waterline and collection waterline which is extracted by different resolutions of DEM data and in the case of different threshold values of plane curvature are analyzed, so that the ef- fects of the extraction of dividing waterline and collection waterline which is caused by uncertain factors are reflected. It provides some basis to obtain hydrological parameters accurately in the region.