机构地区: 西北大学城市与环境学院城市与资源学系
出 处: 《水土保持通报》 2007年第2期56-60,共5页
摘 要: 基于人工降雨实验获取的黄土模拟小流域高解析度DEM数据,提取其不同发育阶段的地形指数,分析了黄土小流域降雨侵蚀过程中地形指数的空间分异特征、平均地形指数变化规律及地形指数频率分布曲线特征。研究证明,地形指数空间分布与地形呈现很强的相关性,地形指数均值与坡度均值呈现对数变化关系,地形指数频率分布图随地形变化呈现规律性变化。地形指数空间变异特征分析可为研究流域地形和流域水文相似性提供基础资料。 As a physical index to express the information on topography, topographic index is a very important parameter for many physically based hydrological models. This article analyzes the topographic index based on a small tested loess watershed. The topographic index is derived from DEMs of the watershed by using the single flow direction method. Results show that the spatial distribution of the topographic index has a high correlation with terrain distribution. Average topographic index variance has an exponential relationship with average slope variance. Frequency distribution of the topographic index shows a regular change with changed topography. The analysis of the topographic index variance can help us study catchment topography and hydrological similarity.