1. Institute of Ecology, College of Urban and Environmental Science, and Key Laboratory for Earth Surface Processes of the Ministry of Education Peking University Beijing China
2. China Grassland Research Center, School of Grassland Science Beijing Forestry University Beijing China
3. Center for Statistical Science, Department of Industrial Engineering Tsinghua University Beijing China
4. The Finnish Museum of Natural History University of Helsinki Helsinki Finland
5. Department of Life Sciences Imperial College London Ascot UK