基于Arc Hydro Tools的流域特征自动提取——以贵州省内乌江流域为例

简要回顾和讨论了基于栅格数字高程模型(DEM)自动提取流域特征的原理和方法,介绍了一个新的基于ArcGIS开发的提取流域特征的工具ArcHydroTools,基于ArcHydroTools提取流域特征包括5个流程:DEM的预处理、水流流向的确定、汇流栅格图的生成、河网的自动生成、子流域边界的划分。最后以贵州省内乌江流域为研究区进行了试验,试验结果表明:提取结果的精度在总体上是符合要求的,但在地势平坦区或人类活动干扰较大的地区,提取的结果与实际相差较大。从提取的效率和试验结果的精度两方面来看,基于ArcHydroTools的流域特征自动提取是切实可行的。

AUTOMATED EXTRACTION OF WATERSHED CHARACTERISTICS BASED ON ARC HYDRO TOOLS: A CASE STUDY OF WUJIANG WATERSHED IN GUIZHOU PROVINCE, SOUTHWEST CHINA

The principles,methods and processes of automated extraction of watershed characteristics based on raster digital elevation models(DEMs) were reviewed and discussed.Then a new tool set named Arc Hydro Tools that is utilized to extract watershed characteristics was introduced,developed as an ArcGIS interface.The Wujiang watershed in Guizhou Province,Southwest China,was taken as a case study using the new tool set.The process of this tool set to extract watershed characteristics includes preparing DEM,building flow direction matrix,building flow accumulation matrix,building river drainage network and getting watershed boundary and small watershed boundaries.By comparing the river network delineated from DEM with the actual river network,it can be concluded that the delineated river network is generally in accord with the actual river network,but in flat areas or areas that are changed greatly by people the delineated river network is much different from the actual river network.In view of efficiency and precision,it is viable to use this new tool set to extract watershed characteristics.