Enveronmental Impact Assessment Of Railway Network Planning:methodology And Its Application

The implementation of railway network planning will occupy much of the land and consume a lot of other natural resources; what's more, it will have great impacts on the ecological environment of the planning area. The application of environmental impact assessment (EIA) in railway network planning, as a strategic EIA at the planning level, will help evaluate the environmental impacts resulting from the implementation of railway network planning as a whole.The construction of railway network occupies much of the land and consumes a lot of natural resources; what's more, it has great impacts on the ecological environment of the planning area. The environmental impact assessment of railway network planning, as a kind of decision means aiming at sustainable development, is a strategic EIA at the planning level, whose purpose is coordinating environment and development while planning scheme forming.The railway project belongs to non-polluting, ecological impacting project, which has more impact on the ecology system and less impact on environmental pollution. Its planning environmental impact assessment attaches great emphasis on ecology and social economy impact assessment on a macroscopic level. By systematically analyzing the relationship between the railway network planning layout and regional sensitive environment, choosing suitable evaluation methodology, the environmental impact of the railway network planning implementation was analyzed and predicted comprehensively so as to find out the cause of the environmental impact and the objects that need to be protected. In a view of which, the preventive environmental protection measures and the reasonable planning scheme were pointed out. The ultimate goal is to reduce the possibility of the environmental impact and destruction resulting from railway network construction and provide scientific proof for railway network planning.Starting with analysis of characteristics of the railway network plan, the contents of the railway network plan, the relationship between railway network and the environment, the limiting factors in making and implementing the railway network planning were discussed, on account of which, it was pointed out that the design of network size, the spatial layout of railway network and the ecological construction measures in the network planning are major factors. Also, we analyzed the impacts on the landscape ecology, hydrological environment, biodiversity and land use changing resulting from the implementation of network planning.After analyzing environmental impact mechanism of railway network planning, the thesis further defined the concept of environmental impact assessment of railway network planning, differentiated the differences between environmental impact assessment of railway network planning and environmental impact assessment of survey, planning analysis, identification of environmental impact and evaluation index, forecast of impact and assessment, sustainability assessment and public participation. What's more, by comparing three different index constructing modes, the environmental evaluation index system based on value model was proposed. Besides, the thesis gave a deep discussion about planning analysis, environmental impact forecast and assessment and environmental sustainability assessment, upon which, the method of forecast and assessment both at microscopic and macroscopic level was pointed out.As for railway network planning, based on sustainable development theory, landscape ecology theory and environmental economics theory, the thesis composed the analysis and measurement system of ecological environmental impact, harmony between network planning and social economy, uncertainty and risk of railway network, follow-up assessment of railway network. The environmental impact assessment mode of railway network planning was constructed from five macroscopic angles, namely ecological environmental sensitivity, resource and environment carrying capacity, integrity of ecosystem, biodiversity and ecological service value. At the meantime, the thesis constructed ecological system integrity assessment model consisting of biological factor, landscape pattern and natural productivity, resource and environment carrying capacity assessment model consisting of resource, environment and ecological factor. Furthermore, the thesis made a discussion on the suitability analysis method of network planning, analyzed the uncertainty of the network planning, came up with the thinking of risk assessment, constructed the environmental impact monitor and follow-up assessment system.In the last part of the thesis, the ecological impact assessment model and suitability analysis method of network planning were applied to the environmental impact assessment of the Beijing-Tianjin-Hebei region around Bohai railway network planning, which was just to examine the feasibility of the model and method. It turned out that the methodology proposed by this article had the character of good operability, and was suitable for environmental impact assessment of linear network planning.