基于DEM的六盘山地势起伏度研究

Analysis of relief amplitude in Liupan Mountain based on DEM

地势起伏度是定量描述地貌形态的一个重要手段,同时也是划分地貌类型的重要指标。本文基于ASTER-GDEM数据,在ArcGIS软件下,利用邻域分析方法获取了六盘山区地势起伏度,并确认本区的最佳统计单元为1400×1400窗口,即1.96 km^2,在此基础上对六盘山区地势起伏度进行了五级分类。结合地形带状剖面线方法,初步分析了六盘山区地势起伏度的空间变化特征。结果表明,研究区内大部分起伏度小于500 m,起伏度较小,六盘山西部地区起伏大于东部地区,六盘山北南走向上从北至南起伏度逐渐增大,研究区内小起伏山地所占比例最大,为51.23%,其次为丘陵,占45.53%,台地、中起伏山地和平原所占比例都很小。

Relief amplitude is not only an important method to quantitatively describe topographic characteristics, but also an important tool for the division of geomorphologic types. Based on ASTER-GDEM Data, the authors analyzed relief amplitude in Liupan Mountain using neighborhood statistics of ArcGIS and obtained 1400×1400 mesh size （1.96 km^2） as the optimum statistical unit. Relief amplitude grade map was then calculated. With the assistant of swath profiles, we preliminarily analyzed the relief amplitude of the study area, the result shows that, relief amplitude in most of the study area is less than 500 meters and the land of west Liupan Mountain is larger than that of eastern Liupan Mountain. From northern to southern Liupan Mountain, relief amplitude decreases gradually. Low relief mountain and hill reach 51.23% and 45.53% of the study area respectively, while platform, intermediate relief mountain and plain are all of very little percentage.