1. State Key Laboratory of Cryospheric Sciences, Cold and Arid Regions Environmental and Engineering Research Institute/Tianshan Glaciological Station, Chinese Academy of Sciences, Donggang West Road 320, Lanzhou 730000, China
2. RWTH Aachen University, Templergraben 55, Aachen 52056, Germany
3. College of Geography and Environmental Science, Northwest Normal University, Anning East Road 967, Lanzhou 730070, China
4. Southwest Forestry University, Faculty of Ecotourism, Bailongsi 300, Kunming 650224, China