Vegetation Investigation And Landscape Construction On Riparian Zone Of The Twain Rivers In Chongqing

The riparian zone is a kind of freshwater and terrestrial ecotone landscape, is a typical ecosystem transition zone. Riparian and its vegetation have many important aesthetic and social-economic functions as well as ecological functions, such as percolating sediment, protecting soil-water, stabilizing river shore system, conserving stream water quality, and promoting biodiversity conservation. With the Three Gorges project actualizing, there will be permanent Water-Level-Fluctuating at riparian zone. It belongs to the riparian ecosystems, its downthrows will up to 30m (from 145 meters to 175 meters) . Changing of the hydrology of Yangtze River, will influence the plant community in riparian zone. The development direction of vegetation there will -make great effects to the ecosystem environment. The riparian zone will be done in Chongqing, it belongs to the Water-Level-Fluctuating.In this dissertation, the plant community was studied on riparian zone of the twain rivers (the Yangze river and the Jialing river) in Chongqing. On the basis of vegetation investigation, we analyzed the biological and ecological characteristic of main local plants, studied plant community types, species composition, distribution with elevation. Then, according to the results of survey and analysis, we bring forward different construction modes of community landscape on riparian zone due to site conditions, provide scientific gist to the riparian virescence in the city of Chongqing and other towns in reservoir zone.Field investigation showed: 1) The predominance plants are annual herbs, perennial herbs and shrubs in riparian zone. 2) The nature communities are mostly formed with boscages and herbages, which formed simplex and complex types. 3) The community distributed with humidity grads vacuum, which is low herbage, high brushwood and shrubbery. 4 )The distribution of community are effected by different radix and soil. 5) Mostly Gramineae plants are able to bear submerging 1 month, but the boscages are well between 1 week and half month. 6) There are some species are feasible in riparian virescence, such as herbage, including Cynodon dactylon, Deyeuxia...