基于DEM的地形起伏度算法的比较研究

Algorithm Comparison of Relief Amplitude Based on Dynamic Effect Model

地形起伏度是描述宏观地形变化状况的地形因子,可作为区域水土流失评价的地形指标之一。基于全国1 000m分辨率DEM分别选取黄土高原、四川盆地、横断山区、东南丘陵、山东丘陵、东北地区6个典型样区,采用局地高差法、局地标准差、表面积与投影面积比、RUGN法、矢量法、RDLS(地表起伏度)6种算法进行起伏度的提取,对提取结果进行了对比分析,并对各种算法的提取结果进行了信息容量计算。结果表明,局地标准差和局地高差法是两种相对较好的提取起伏度的方法,且针对不同的地形区,不同起伏度算法也具有各自的适宜性。

Relief amplitude is used as one of the terrain factors to describe the macroscopic topographic change, which can be used as one of the topographic indexes for evaluation of regional soil and water loss. The Loess Plateau, Sichuan basin, Hengduan mountainous region, Southeast hills, Shandong hills and northeast regions 6 typical samples were selected based on dynamic effect model（DEM） of 1 000 resolution of China, relief amplitude was extracted with the 6 methods of local elevation range, local standard deviation, the ratio of surface area and the projected area, RUGN, the vector method and relief degree of land surface （RDLS）. The results of extraction were analyzed, and then the amounts of information were calculated. The results showed that local standard deviation and local elevation range were the two better methods, and dif- ferent regions have different suitability.