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Poyang Lake is the largest fresh water lake in China, as well as a seasonal, water-type, throughput-type lake. It bears the following five big rivers:Gan River, Fu River, Rao River,, Xiu River, and purs into Yangtze River through the lake outlet afterstorage. What’s more, Poyang Lake, one of the ten ecological functional reserves as well as one of the global biotas delimited by the World Wildlife Fund, plays a very important role in regulating and storing flood, protecting the special ecology of the biodiversity and maintaining regional and national ecological security.For years, the ecological environmental pollution is increasing in Poyang Lake area alongwith the agricultural and industrial development, urban expansion, increase of population and soil erosion.In such a situation, it is very important to make evaluation and research, to precict the environmental pollution development trend and to make related protection countermeasure in Poyang Lake area in order to be completely aware of the ecological problem and pollution development trend it may confront with, in order to improve the ecological protection of the lake area as well as in order to realize the regionally economic, social and ecological benefit maximum.The present paper chooses the analysis evaluation method based on GIS and remote sensing by refering to the related document at home and abroad, knowing the research status in this field, making a study on the basic theory of land ecological environmental evaluation, and analyzing the technical way of land ecological environmental evaluation, according to the actual situation of the studied area.By collecting and analying the data and information of the nearby 29 counties and districts, on the basis of evaluation of surrounding soil and surface water and the image data of Landsat TM 5 in 2005, the present paper makes a evaluation study on the land ecological environmental quality by use of GIS and romote sensing.By analying the romote sensing data, we can get the available land of all kinds of land aound Poyang Lake area, by caculating the conditional grade of the lake area according to the El caculation formula, we can get the land use map, then we can further analyze the current situation and existing problems, thus, we can put forward the solutions to the ecological and environmental problems of the area.Thus, we can provide basic scientific data for the ecological environmental situation, also, we can provide scientific basis and technical support for ecological environmental protection and promotion of the sustainable use of the area as well as the reference for the planning and decision making of the area. The present paper mainly includes the following aspects:(1) Basic theory research. The paper analyzes the concept and connotation of ecological environmental evaluation of land and the theory it bases on. They are:sydtem theory, ecology theory, environmental resources value theory, environmental economic theory, regional sustainable development theory and land optimization disposition theory.(2) Technology research. To know the adopted ways by document research. They are: single index evaluation method, the evaluation method based on remote sensing and GIS. By using and improving the evaluation method to soil and water of Ministry of Environmental Protection, the present paper puts forward technical method of evaluation.(3)The practical research on the ecological evaluation of soil based on remote sensing and GIS. Based on the land use data and other data, the present paper comes to the conclusion that the ecological environmental situational level of the nearby 29 counties and districts is good,19 (79%) of them are excellent, at the same time, there also be the land use map. Thus, we can say, the overall ecological environment is good, the vegetation coverage is high, the bildiversity is rich, the ecological system is stable, the air and water condition is good, it is more suitable for human survival.75.2% of the lake area is forest and agricultural land, and 15.4% is wet land.(4) Studies on ecological environmental problem. According to the ecological environmental problems of the lake area, taking various factors into account, the present paper puts forward 7 feasible suggestions, and ponits out, at the same time, the protection supervision and management on resource devepment activities should be strenghened by applying methods of law, administration, economy, technology and education.
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