Restoration of Natural Herbaceous Vegetation of Xiangxi River's Water-Level Fluctuation Zone after the Flooding in Three Gorges reservoir Area

Water-level fluctuation zone (WLFZ) is the security barrier of reservoir. Herbaceous vegetation's restoration characteristic of Xiangxi River's WLFZ in Three Gorges reservoir area was investigated by using ecological methods. The results show that: The main plant types are annual herbs and perennial herbs, and plant communities are patchiness or zonal distribution. Two absolute dominant plant communities are build by Cynodondactylon(Linn)Pers. and Rhizoma Cyperi (Nutgrass Galingale Rhizome) in the 145-155m area, and annual herbs are mainly distributed above the 155m area. As the elevation increasing, the 13 diversity increases. There are 22 dominant species of herbaceous in Xiangxi River's WLFZ, 16 plants could complete life story, and 5 plants' life story are threatened by impounding. Polygonum lapathifolium Linn.may not complete its life story.