Abstract:Vegetation within the working area would be completely destroyed and the adjacent areas would be affected by the construction of West-East Pipeline Project. This will result in further environmental deterioration and serious water and soil loss, that will in turn threaten the safety of the west-east pipeline (WEPP) from the long term. Thus it is of highly significance to improve the regional ecosystem function and practical for the safe operation of pipeline to control the water and soil loss along the pipeline with the purpose of establishing a friendly environmental system. In this paper, based on analysis of factors that affect ecosystem sensitivity to the water and soil loss, soil, vegetation, slope aspect and slope degree were selected as assessment indices to make an assessment of the water and soil loss sensitivity by assigning weight to each factor based on experts' knowledge under the support of GIS. Furthermore, according to overlay model of layer weightiness - classification marking and Fuzzy-classification, the study area within 10km of both sides along the pipeline was divided into four groups, which were the slightly sensitive area, the moderately-sensitive area, the sensitive area and the highly sensitive area. The spatial characteristic of sensitivity to water and soil loss was assessed and main reasons causing water and soil loss was then discussed. At last, basic measures of ecological recovery and friendly environment construction in term of the safety of both regional ecosystem and pipeline were discussed.