| It is widely recognized that all the areas of wetlands on Earth, which are belonging to one of the three major sorts of ecosystems on the planet, are certainly quite important for nature and mankind as their irreplaceable roles in maintenance of biodiversity. And in China, the hydro-fluctuation zone (HFZ) in the Three Gorges Reservoir, its largest area of artificial wetland-ecosystem which has formed with the construction of the dam, is believed to be one piece of Chinese largest'environmental fortune'that its eco-environment has important implications contributing to managing and protecting the HFZ and eco-security in the Three Gorges Reservoir and, more significantly, successfully implementing the freshwater-resources-reserving strategies of this country.In this thesis, an empirical assessment of eco-environment of HFZ in Zhongxian County was carried out utilizing the data collected by social and economic statistics, environmental monitoring, remote sensing interpretation and site investigation. But before that, I would firstly introduced a conceptual index-system applying the Press-State-Respond (P-S-R) Model on the basis of status surveys and previous researches summations, which has been proved to be a satisfactory one in the aspects of rationality and application that the evaluation outcomes were almost consistent with the real conditions of HFZ in Zhongxian County.It turns out that it is the joint function of four main pieces of shortages (i.e. defective natural conditions, widely contaminated soil-and water-environment, heavily destroyed eco-systems and imperfect management mechanisms), more precisely, geological conditions and human disturbances, that to be an explanation of the poor eco-environmental conditions of HFZ in Zhongxian County. On the one hand, the most common environmental issues of this area (e.g. acid rain, soil erosion and geological hazards) can be well explained by the bad geological conditions such as mountainous terrains (that are not conductive to diffuse the pollutants in the air), numerous geological-disaster-prone locations and heavy precipitations in summer. On the other hand, human disturbances have caused many great damages to the environment (e.g. soil- and water-pollution by emissions, vegetation coverage declining to 20.49 per cent and landscape fragmentation going up to 6.56) due to the imperfect management mechanisms and inefficient ecological reconstructions. I argue that:a. The responsibilities, authorities and benefits for each piece of land in the area of HFZ should be clearly defined.b. It seems necessary to accomplish a comprehensive ecological function zoning of HFZ and its surrounding area that the core area of HFZ (or water-land adjacency area) is designated for wetland-restoration; the adjacent area of HFZ is marked off as a buffer zone and the outermost region is for exploitation.c. Those destroyed vegetation systems should be restored to gradually improve creature'habitats and the whole eco-systems in this area.d. It should be brought to the government's attention of geological hazards monitoring and prevention.e. Environmental monitoring and pollution-controlling equipments are also noteworthy.f. Encourage more people to engage in environmental protection.g. Better mechanisms and manners (e.g. multi-steps governance) of management should be put forward.
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