1. State Key Laboratory of Urban and Regional Ecology, Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
2. College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100149, China
3. School of Environment and Natural Resources, Renmin University of China, Beijing 100872, China
4. Key Laboratory of Karst Dynamics, MNR & Guangxi, Institute of Karst Geology, Chinese Academy of Geological Sciences, Guilin 541004, China