Eco - Environmental Impact Assessment Of Yulin City Based On

The ecological environment is fundamental to human survival and development, a good ecological environment is the important guarantee of existence and development of human society. Yu Lin is located in northern of the Loess Plateau, this area is ecological fragile district and sensitive to environment change, it is also the focus of the climate and ecological environment change research area. Yu Lin is the national important energy base, in the process of the development of the western region in recent years obtain the unprecedented development of economy and society. However, ecological problems resulting from economic and energy development are appeared in slowly, coordinate the relationship between the economic, social and ecological is important strategic significance to the sustainable development of Yu Lin.In this paper, using Yu Lin’s land use, soil erosion and environment data from2000to2010as the foundation. According to the assessment system of the "Technological Standard for Evaluation of ecological environment(Trial Version)"(HJ/192-2006), Evaluation indexes are optimized by the analytic hierarchy process (AHP) to establish more accord with the actual situation of Yu Lin city ecological environment evaluation index system, with assessment unit combined with polygon assessment unit from vector spatial data and Point assessment unit from grid spatial data, using the "3S" technology to evaluate the ecological environmental quality research of Yu Lin. Through the ecological environmental quality index of2000and2010in Yu Lin, summed up the change trend of ecological environment and the existing problems in Yu Lin between2000and2010. From the perspective of the natural and human factors to discuss the cause of Yu Lin ecological environment change, putting forward the future of Yu Lin ecological environment planning, management and construction of corresponding suggestions and measures, and offer reference to the relevant departments. The specific conclusions are as follows:(1) From the evaluation result, the overall ecological environment quality index of2000and2010in Yu Lin are on the law side, and presented decline trend, The ecological environmental quality is general, the vegetation coverage is medium, the general level of biodiversity is general, more suitable for human survival, but there is not suitable for human survival conditionality factors appear, in the process of social and economic development and urban construction, the ecological environment has no obvious change. But water resources and environment pollution is human survival conditionality factors.(2) From2000to2010, each district and county of Yu Lin’s ecological environment index has an obvious space change, the northern six counties of Yu Lin’s ecological environment are better than six south county in2000, including the county of Fugu, Shenmu, Jiaxian, Hengshan, Dingbian and Yuyang district, these six counties’ ecological environment level is good, another six counties’ecological environment level is regular; But the situation has changed obviously in2010, the county of Fugu, Shenmu, Jia xian, Hengshan, Jingbian, Zizhou and Yuyang district, these seven counties’ ecological environment level is regular, another five counties’ecological environment level is well, the southern six counties of Yu Lin’s ecological environment are better than six north county in2000.(3) In recent years the country issued a series of policies and regulations, such as natural forest protection project, returning farmland to forest and grass, land desertification prevention and control, these measures promote the increase of the loess plateau vegetation coverage. Especially six south counties, these regional ecological environment index is higher, the ecological environment is improved effectively; But the six northern couties in Yu Lin, especially in the energy development zone and its surrounding area, these areas of urbanization and industrialization process accelerated and with a lot of energy development and exploration area, these regional ecological environment index is lower, energy resources are a large number of pollutants in the process of mining development to the resources and environment, energy development and pollutants inevitable cause damage to the ecological, combined with the region belongs to the ecological fragile district, natural ecological environment condition is relatively poor, lead to the ecological environment quality deteriorating in these region. Therefore, ecological environment on the basis of maintain current levels in Yu Lin, should constantly improve the districts and counties of vegetation coverage, strengthen management of soil and water loss. At the same time, adopt corresponding measures to control the emissions of pollutants of the energy development zone and as far as possible to reduce the development of polluting enterprises. (4) Human factors accelerates the change of the ecological environment, human activities have become an important factor in the ecological environment change. The rapid economic development, population increases, unreasonable agglomeration of industrial structure, and large number of industrial "three wastes" pollution in the process of the industrial activities, These are the dominating factor for decreasing the quality index of ecological environment in Yu Lin, The returning farmland to forest and grass, tree planting, management of soil and water loss and other projects play an important role in the improvement of the ecological environment sustainable development. So in the future development, we should pay more attention to the economic development and the coordinated development of ecological construction, implying a sustainable development road.The innovative points of this study are as follows:(1) Because the evaluation area across different regions, and in different parts of the whole ecological environmental quality exist significant regional differences, combined with biological abundance index and others evaluation index, the general ecological environment quality in time and space scales comprehensive evaluation and comparative analysis of the ecological environment in Yu Lin.(2)Using the analytic hierarchy process (AHP), use SO2、COD、 solid waste and soot as the index of environment quality index and recalculate the weight, improve the environmental quality evaluation index of Yulin city.(3) Combined with the actual situation of the ecological environment of Yulin city, use lkmxkm resolution raster point unit as the index data of carrier and basic evaluation and analysis unit of each index, use county level administrative region of the vector planar unit as comprehensive evaluation analysis unit, Combination with the two evaluation units, utilize the "3S" technology to conduct a comprehensive evaluation of ecological environment in Yulin. Through the whole space and the internal differences to master the current situation of the ecological environment of Yulin.