1. School of Geography and Environment, Jiangxi Normal University, Nanchang, China
2. State Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
3. National Engineering Research Center for Geoinformatics, Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing, China
4. Geography Department, San Diego State University, San Diego, CA, USA