Characterizing Pattern of Topography and Geomorphology in the Hengduan Mountains, Southwest China

The Hengduan Mountains, situated on the southeastern edge of the Qinghai-Tibet Plateau, are the longest and widest north-south-oriented mountain range in China, exerting a significant influence on the ecological and geographical pattern. Understanding the topographic and geomorphological characteristics of the Hengduan Mountains is fundamental and crucial for research in related fields such as ecology, geography, and sustainability. In this study, Digital Elevation Model (DEM) data were utilized to extract and analyze the topography and geomorphology (TG) pattern. TG maps have been developed to quantitatively classify the TG types in the Hengduan Mountains by combining the five factors of elevation, slope, aspect, relief and landform. The spatial distribution and quantitative characteristics of these factors were mapped and investigated using geographic information systems. The results revealed that: (1) The Hengduan Mountains exhibit an elongated north-south distribution, with an average elevation of approximately 3746 m, an average slope of around 25°, and an average relief of about 266 m. (2) The Hengduan Mountains display significant elevation differences, with an overall high elevation, characterized by a trend of lower elevation in the east and higher elevation in the west, as well as irregular orientations of various aspects. (3) The 19 landform types were identified; the landform types of the Hengduan Mountains are primarily composed of low-relief high-mountains (42.0618%), low-relief mid-mountains (22.4624%), and high-elevation hills (20.5839%). The results of the study can provide data and information support for the ecology, environmental protection and sustainable development of the Hengduan Mountains.