Abstract:

The water level fluctuation is one of the basic characteristics of wetland ecosystem.This paper aimed to study the effects of water level fluctuation on the characters of plant community in the littoral zone of Three Gorges Reservoir (TGR).The composition and structure of plant community of littoral zone of Baijia stream were investigated in August 2010.The results showed that there were 34 families of vascular plants including 70 genera and 85 species.The vegetations were divided into 18 community types by TWINSPAN classification, among which Ass.〖WTBX〗Cynodon dactylon〖WTBZ〗 and other 4 communities were the most representative plant communities.The composition of vegetation showed a transition from xerophytes to hygrophytes with the increasing of flooding intensity.Shannon index,Pielou index,Richness index and plant biomass showed a distribution of “∧” type,while Simpson index showed a distribution of “∨” type varying with the waterlevel fluctuation.The quantity of plant species,the composition and types of community and the diversity were different from the hydrology of 156 m.Waterlevel fluctuation was one of the main driving factors of vegetation change in the newly wetland