1. Key Laboratory for Humid Subtropical Eco-geographical Processes of the Ministry of Education, Fujian Normal University, Fuzhou, Fujian, China
2. School of Geographical Sciences, Fujian Normal University, Fuzhou, China
3. Key Laboratory of Restoration Ecology for Cold Regions in Qinghai, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, Qinghai, China
4. Institute of Applied Remote Sensing & Information Technology, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, Zhejiang, China