1 Chongqing Jinfo Mountain Karst Ecosystem National Observation and Research Station, School of Geographical Sciences, Southwest University, Chongqing 400715, China. hongyanghy@gmail.com.
2 Department of Geography and Environmental Science, University of Reading, Reading RG6 6AB, UK.
3 Chongqing Jinfo Mountain Karst Ecosystem National Observation and Research Station, School of Geographical Sciences, Southwest University, Chongqing 400715, China.
4 Department of Geography, University College London, London, WC1E 6BT, UK.