基于DEM数据的澜沧江-湄公河流域地形起伏度研究

 澜沧江-湄公河是世界第六大河,流域地形地貌复杂,景观类型多样.作者运用GIS的空间分析和数理统计等方法,基于STRM 90 m×90 m DEM,提取了基于栅格尺度的澜沧江-湄公河流域地形起伏度,并从整体特征、垂直地带性和纬向分布规律3个方面系统分析了澜沧江-湄公河流域地形起伏度的分布规律.研究表明:①澜沧江-湄公河流域地形起伏度以低值为主,63.47%的区域地形起伏度低于1个基准山体(相对高差≤500 m),地形起伏度越高的地区,平地比例越低,反之亦然;②随着海拔高度增加,澜沧江-湄公河流域地形起伏度呈现逐渐升高趋势,在海拔3 500~3 599 m和5 800~5 899 m存在2个峰值,所在区域均位于横断山脉地区;③随着纬度的增高,澜沧江-湄公河流域地形起伏度呈逐渐升高趋势,同时存在5个峰值,纬度由南向北、由低到高分别是12°N、16°N、19°N、25°N和29°N,所处地区分别是柬埔寨的豆蔻山脉、老挝境内的安南山脉南部的丘陵地区、安南山脉中北部、澜沧江中段和南段交汇处、西藏东南角的横断山脉地区.

The study on the relief degree of land surface in the Lancang-Mekong River Basin

Lancang-Mekong River is the sixth largest river basin in the world,its terrain is very complex,with various types of landscape.This paper used spatial analysis with GIS software and mathematical statistics method,based on STRM 90 m×90 m DEM data,to extract the Relief Degree of Land Surface(RDLS) of the Lancang-Mekong River Basin based on grid-scale,and systematic depicted the distribution rules of RDLS in three separate ways:overall characteristics,vertical zones and zonal distribution rules.The research can provide quantitative basis and scientific reference with the whole basin terrain-geomorphologic maps and evaluation of the resources and environment.The result showed that ① The majority of the RDLS is low in Lancang-Mekong River Basin,for more than 63.47% of the area with the RDLS lower than 1 (relative altitude≤500 m).The higher the region’s RDLS is,the lower its proportion of plains is,and vice versa;② As the altitude increasing,the RDLS in Lancang-Mekong River Basin shows gradually increasing,and at the altitude of 3500~3599m and 5 800~5 899 m,there are two peaks,which located in the Hengduan Mountain;③ As the altitude increasing,the RDLS in Lancang-Mekong River Basin shows gradually increasing,and there are five peaks,from south to north,low to high,they are 12°N,16°N,19°N,25°N,and 29°N,the places where they are located are the following:Cardamom Mountains in Cambodia,southern hilly areas of Annan Mountains,north-central areas of Annan Mountains in Laos,the interchange of middle and southern section of the Lancang River Basin,south-east corner of the Hengduan Mountain area in Tibet.