1. Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China
2. School of Environment and Planning, Liaocheng University, Liaocheng 252000, China
3. Faculty of Infrastructure Engineering, Dalian University of Technology, Dalian 116024, China
4. Department of Earth Sciences, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana 46202, United States
5. Biology Department, San Diego State University, 5500 Campanile Drive, San Diego, California 92182, United States
6. University of Chinese Academy of Sciences, Beijing 100049, China