1. Key Laboratory of Ecosystem Network Observation and Modeling; Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences; Beijing 100101 China
2. State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau; Northwest A&F University; Yangling 712100 China
3. College of Resources and Environment; University of Chinese Academy of Sciences; Beijing 100190 China
4. State Key Laboratory of Loess and Quaternary Geology; Institute of Earth Environment, Chinese Academy of Sciences; Xi'an Shaanxi 710061 China