Abstract:

The plant functional group composition and species diversity in different succession stage at degraded plateau wetland of Napahai were studied. The results showed that as the succession from primary swamp to swampy meadow,to meadow,and to reclaimed wetland,the compositive species of natural plant community including accompanying species increased,while the occurrence of dominant plant species reduced,which makes the community structure complex.With the deflected succession of aquatic ecotype plant functional group,the dominance of mesophytes and xerophytes increased,while the dominance of aquatic and hygric plants decreased. However,there are only planting crops in the reclaimed wetland. In the composition of plant biotype functional group,the hydrophytes reduced quickly with the deflected succession and the dominance of perennial herbs is mostly marked,and there are only annual herbs in reclaimed wetland. Compared with primary swamp,the species diversity index (richness and diversity index) of meadow is the highest,the swampy meadow follows,and the reclaimed wetland is the lowest. It was clearly showed that the characteristics of plant functional group compositions and species diversities in Napahai Wetland are a respondance of wetland environment changes under human disturbances,which indicates the changing of wetland ecosystem and losing of wetland functions.

Key words: plateau wetland, plant functional group, diversity, Napahai