1. Key Laboratory of Watershed Geographic Sciences, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China
2. University of Chinese Academy of Sciences, Beijing, China
3. Key Research Institute of Yellow River Civilization and Sustainable Development & Collaborative Innovation Center for Yellow River Civilization of Henan Province, Henan University, Kaifeng, China
4. Department of Geography, University of Utah, Salt Lake City, UT, USA