Study On Landscape Ecology Method Of Transportation Eco-Environmental Impact Assessment

With the rapid development of transportation, the influence of transportation project on environment has increasingly been people's focus. The environmental problems of transportation project are mostly embodied in those problems of water, air, sound and ecology. Comparatively speaking, the assessment methods on the eco-environmental lag behind the more mature ones on the problems of water, air, sound and so on. Especially because the transportation project features in longer lines and multiplicity of ecosystem that it crosses, and because the present methods give priority to qualitative description while the quantitative indexes are less, and even can not be quantitated, the reliability of the assessments methods on ecology have been effected to some extent.Landscape Ecology is a newly developed subject in recent decades and modern landscape ecology has become a notable branch in the field of ecology. Alongside the development of landscape ecology, the application of Landscape Ecology to the eco-environmental assessment has become a more advanced one in the field of the eco-environmental impact assessment both home and overseas. It refers to, with the application of the principle of Dominance, calculating dominance and analyzing the changes of dominance before and after project construction to assess the eco-environmental impact caused by project construction. However, discussion of its theory is more than its application. It has been applied in region exploitation project once or two, while even less in line type project, such as highway construction project. Moreover, as far as the features of transportation's impact on the eco-environmental, this method just considers the changes of the land patchs, neglecting the land patterns, which likewise affect the function and stability of ecosystem. Therefore, it is necessary to complement the method as to the features of transportation project eco-environmental impact.On the basis of the existing method of application of Landscape Ecology to the eco-environmental assessment, this paper complemented and further studiedthe method. Starting with the principles of the eco-environmental assessment, with the landscape pattern index as a major including frequently used dominance index, it applied the related theories of Landscape Ecology to analyze the changes of modes and patterns of land utilization, and then assessed the consequent eco-environmental changes. Its main content included the follows:First, study the feasibility of the application of Landscape Ecology to the eco-environmental assessment: theoretically, it analyzed the difference between landscape ecology and the traditional ecology and, starting with the principles of the eco-environmental assessment, discussed the related theory of Landscape Ecology. In the aspect of study methods and techniques, briefly introduced the application of 3S in landscape ecology (GS, GIS and GPS).And then the corresponding theories with landscape ecology were introduced as to the features of transportation eco-environmental impact.Second, through analysis of the above theories, it chose corresponding index—landscape index including number of patches, patch area, fractal dimension, diversity index, dominance index, etc.. Third, with corresponding theories and indexes, it introduced the methods and steps of the application of Landscape Ecology to the eco-environmental assessment.At last, it took the new-built Tanggula Mountain Pass to Lhasa City of the Qinghai-Tibet Railway for example to carry out research. It calculated and analyzed the change of landscape pattern in the around railway line scope of 2km before and after railway construction, then analyzed the influence of eco-environment combining the feature of eco-environment of Qinghai-Tibet Plateau and ecosystem frangibility. Show as a result, the influence upon marsh ecosystem is biggest. The influence also has certain degree for high and cold grassland, high and cold meadow grassland and high and cold meadow ecosystem. When being under construction in process and after construction, so we should pay attention to the recovery and protection work for vegetation during and after construction.