青藏高原地貌形态总体特征的GIS识别分析

Recognition of General Topographic Features in Qinghai—Tibet Plateau Based on GIS

长期以来,青藏高原都是国内外地质及地理学研究重点关注的地区。青藏高原范围不同于行政区划,基于不同标准和目的得到的范围存在一定差异。基于地貌形态特征,利用SRTM数据和数字地形分析方法,在ArcGIS软件的支持下,半自动地提取了青藏高原的边界,并对青藏高原的地貌类型进行了自动识别划分,获得了高原16种地貌形态分布图。研究结果表明,青藏高原以高海拔丘陵、小起伏高山、中起伏亚高山和中起伏高山为主,占到青藏高原总面积的60.58%,高原内部地势较平缓,边缘起伏较大,与其相邻区域在地貌形态表现出明显的差异性。

The study of Qinghai—Tibet Plateau has been a focus in geology and geography for researchers home and abroad for a long time.The range of Qinghai—Tibet Plateau is different from administrative division.There are many differences among the ranges based on different criterions and purposes.Based on the characters of topography,we used the data of Aster G—DEM and the method of digital terrain analysis to extract the boundary of Qinghai—Tibet Plateau semi-automatically with supporting of the ArcGIS,and its topography was identified and divided automatically.16 kinds of geomorphic distribution maps were acquired.The results showed that the dominating topographies were high-elevation hills,low-relief high-hill,middle-relief subalpine and middle-relief high-hill,the areas accounted for 60.58% in Qinghai—Tibet Plateau.The terrain was quite gently in inner plateau,had a little large relief in marginal area,indicating significant difference between plateau and the adjacent regions in topography.