Based 3S Technology, Environment Impact Ssessment

Ecological environment quality evaluation of gas field development environmental impact assessment is always the most critical part of the environmental impact assessment of the project. Maowusu desert is located in environment vulnerable area under the semiarid climatic conditions, and Sulige gas field is in the hinterland of the desert. To carry out the environmental impact assessment study of the gas field is beneficial to make the rational use of sand resources and to provide theoretical basis of maximizing the natural resources protection and the maintenance of the desert ecosystem health. The result of the environmental impact assessment can provide technical references to the government in the supervision and administrative decision-making. The characteristics of environmental impact assessment are relevant, dynamic and stochastic, and these features determine how complicated and difficult the problem is. The obvious advantages of 3S technology to solve the problem from the aspects of point area and time are dynamic control, macro correlation analysis and real-time monitoring of the investigation. In this paper, the thematic map of ecological impact assessment is made using the 3S technology. This method does not only overcome the disadvantages of labor and time consuming,poor quality mapping in the "graphics stack law" mapping process, but it also inherits the easy understanding and intuitive characteristics. The quality of the thematic map is good and informative, and the image is clear and structured. The thematic map can meet the requirements of the ecological impact assessment status quo evaluation and prediction, therefore it extends the applied and practical value of TM remote sensing data.This paper uses field investigation and 3S technology as a supplementary means to interpret the vegetation types and land use on the outside expansion within lkm of Sulige gas field with 1:100000 topographic maps and TM remote sensing image as the basis for research base map. While using the information and research results already existed and making reference to "eco-environmental quality evaluation method" promulgated in 2003 by the National Environmental Monitoring Center, the paper makes evaluation on the ecological environment quality of the area. The calculation and analysis results show that:the evaluation region is dominated by sandy soil and the soil surface is deserted severely. The major environmental problems of the region are soil erosion, desertification and the degradation of vegetation, which make the region a sensitive area on the evaluation of ecological environment. Finally, the paper gives the environmental protection and ecological mitigation measures which should be taken combined with the project analysis and ecosystem types of gas field development.