1. Coastal Ecosystems Research Station of Yangtze River Estuary; Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering; The Institute of Biodiversity Science; Fudan University; 220 Handan Road Shanghai 200433 China
2. Department of Microbiology and Plant Biology; University of Oklahoma; Norman 73072 OK USA
3. Center for Earth System Science; Tsinghua University; Beijing China
4. State Key Laboratory of Vegetation and Environmental Change; Institute of Botany; Chinese Academy of Sciences; Beijing 100093 China