1. University of Electronic Science and Technology of China,School of Resources and Environment,Chengdu,China,611731
2. University of British Columbia (Okanagan Campus),Environmental and Geographic Sciences,Department of Earth,British Columbia,Canada,V1V 1V7
3. Chinese Academy of Forestry,Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute,Beijing,China,100091