水土保持通报2017，Vol.37Issue(4)：189-193,5.DOI:10.13961/j.cnki.stbctb.2017.04.032
基于DEM的水系提取及集水阈值确定方法研究
Information Extraction of River Networks and Determination of Drainage Area Threshold Using DEM Data
摘要
Abstract
[Objective] Method of determining appropriate drain area threshold was demonstrated to reflect the actual river drainage network.[Methods] Based on the DEM data of Longchuan River basin,the automatic extraction module of watershed drainage network in ArcGIS software was used to extract relevant drainage information.After that,a function between river network density and catchment threshold was fitted,which was used to determine the appropriate drainage threshold by finding the turning point of its first derivative function and/or the inflection point of the second order derivative.This was simultaneously exemplified by the Longchuan River basin.In this case,the threshold was determined by finding where the ratio change of river network density equal to the change rate of the water drainage threshold.[Results] The river networks under different catchment drainage threshold were compared and found that no obvious differences existed with regard to the catchment threshold length of the main channel and the geographic location,but other features of river network were apparently different.In the case of the Longchuan River basin,its appropriate threshold was thought to be 0.12 km2.[Conclusion] The river network extraction precision varied with the drain area threshold.The proposed method in the determination of the catchment threshold is less subjective,and is more objective,which can be used to provide some bases for the monitoring of regional soil erosion.关键词
DEM/ArcGIS/河网密度/集水阈值Key words
DEM/ArcGIS/river density/drainage area threshold分类
天文与地球科学引用本文复制引用
罗大游,温兴平,沈攀,张皓楠,张丽娟,李进波,郁智..基于DEM的水系提取及集水阈值确定方法研究[J].水土保持通报,2017,37(4):189-193,5.基金项目
国家自然科学基金项目“天空开阔度对城市热岛效应的影响研究”(41101343) （41101343）
