基于DEM的数字流域特征提取研究进展

数字高程模型(DEM)是地表形态高程属性的数字化表达,利用流域DEM数据构建数字水系模型并提取流域水文特征,是分布式水文过程模拟的重要基础。DEM中闭合洼地和平坦区域的处理、流向的确定以及DEM分辨率的大小都直接影响着流域水系特征提取的质量与效率。针对当前基于DEM提取河网与流域特征的诸多问题,阐述了DEM数据提取流域水系特征的原理,回顾了数字水系模型与流域特征提取方法,评述了洼地和平地的处理方法及水流方向的确定方法的研究进展,介绍了当前基于不同DEM数据类型的提取方法研究,探讨了DEM尺度和分辨率对提取流域特征的影响,总结了平缓区域数字水系和河网提取的研究进展。

Advances in digital watershed features extracting based on DEM

Digital elevation models(DEMs) can be considered as a digital representation of landscape topographic properties. Construction of a DEM-based digital model for a drainage network and extraction of hydrological attributes of the drainage network are important premises for simulation of distributed hydrological processes in a catchment. Usually, the quality and efficiency of the extraction of hydrological characteristics of a river basin from DEM data are affected by treatment of the closed depressions and flat areas in DEM, determination of flow directions, and selection DEM resolutions. In this paper, fundamental principles, methods and algorithms for extraction of the features of drainage networks and watersheds are reviewed; research progresses on the methods for treatment of flat areas and depressions and for determination of flow directions are discussed; the progress on software design and development for extractions from different types of DEM data are introduced; the effects of different scales and resolutions of DEM on the extraction of drainage network and watershed features are explored. Furthermore, the research progresses on the extraction of the features of drainage networks in flat areas and plain region are summarized.