1. Erguna Forest-Steppe Ecotone Research Station; Institute of Applied Ecology; Chinese Academy of Sciences; Shenyang 110164 China
2. Urat Desert-Grassland Research Station; Northwest Institute of Eco-Environment and Resources; Chinese Academy of Science; Lanzhou 730000 China
3. National Hulunber Grassland Ecosystem Observation and Research Station; Institute of Agricultural Resources and Regional Planning; Chinese Academy of Agricultural Sciences; Beijing 10008 China
4. State Key Laboratory of Vegetation and Environmental Change; Institute of Botany; Chinese Academy of Sciences; Beijing 100093 China
5. Graduate Degree Program in Ecology and Department of Biology; Colorado State University; Fort Collins Colorado 80523 USA
6. Dipartimento di Agraria, Ambiente e Alimenti; Università del Molise; Campobasso 86090 Italy
7. European Forest Institute (EFI) Project Centre on Mountain Forests (MOUNTFOR); San Michele all'Adige 38010 Italy
8. Sydney Institute of Agriculture; School of Life and Environmental Sciences; The University of Sydney; Sydney New South Wales 2006 Australia
9. Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research WSL; Birmensdorf CH-8903 Switzerland
10. College of Ecology and Environmental Science; Inner Mongolia Agricultural University; Hohhot 010018 China
11. University of Chinese Academy of Sciences; Beijing 100049 China