1. a State Key Laboratory of Earth Surface Processes and Resource Ecology , Beijing Normal University , Beijing , 100875 , China
2. b Computer School of China West Normal University , Nanchong , 637002 , China
3. c Graduate School of Environmental Studies, Nagoya University , Nagoya , 464-8601 , Japan
4. d Aerospace Surveying and Mapping Remote Sensing Information Processing Centre , Beijing , 102102 , China