Ecological Sensitivity Assessment Of The Central Route Of South-to-North Water Diversion Project Reserve

Since the central route of the South-to-North Water Diversion Project was constructed,the ecological environment along the route has been attracting more attention,which ecosystem types are wide variety and have complex ecological environment.The construction of the main canal has various forms.After the construction was completed,the original urban and rural environmental protection system along the route has been changed.The ecological sensitivity along the route has increased and resulted in more and more difficult in the control of environmental risks.The National 13 th Five-Year Plan also clearly stated that it is necessary to “increase the ecological protection of the water source areas of the South-to-North Water Diversion Project and the ecological”.This thesis aims to analyze the ecological sensitivity along the route by using the single factor evaluation method and the comprehensive evaluation method,and identify the areas which need to be protected.The main research contents are as follows:(1)Through reading relational literature,summarizing the research theories and methods about the ecological sensitivity,and the construction basis of the evaluation index factor system,combined with the characteristics of the central route project of the South-to-North Water Diversion Project,the land use types,typical canals,the filling and cutting type,land use changes,vegetation coverage,elevation,slope,aspect and water buffer are selected as evaluation factors to establish an indicator system for ecological sensitivity evaluation indicators.(2)Single factor evaluation of ecological sensitivity: the ecological sensitivity of land use type is mainly slight sensitivity,and the ecological sensitivity of typical canal type is mainly moderate sensitivity.The ecological sensitivity of the filling and cutting type is based on extreme sensitivity,and the ecological sensitivity of land use change is mainly insensitive.the ecological sensitivity of vegetation coverage is slight or extreme sensitivity.The ecological sensitivity of elevation and slope is based on insensitive and lightly sensitivity,the ecological sensitivity of aspect is mainly mild,moderately sensitive and highly sensitivity.The ecological sensitivity of the water buffer zone is extremely sensitive and highly sensitivity.(3)Comprehensive evaluation method of ecological sensitivity: The coefficient of variation method is employed to determine the weight of each factor.The weighted overlay for the 9 factors is conducted in A GIS software to obtain comprehensive ecological sensitivity along the central route project of the South-to-North Water Diversion Project.The results indicate that 99.39% of the areas along the central route of the South-to-North Water Diversion Project have different degrees of sensitivity,mainly in slightly sensitive zone,accounting for 67.50%,followed by moderately sensitive zone,accounting for 31.62%.(4)From the overall analysis of the study area,the ecological environment of the central route of the South-to-North Water Diversion Project reserve is relatively sensitive.In terms of ecological environment protection,it is essential to select appropriate measures according to sensitive types to strengthen protection,especially in areas with moderate sensitivity such as Ye County,Fangcheng County and Xichuan County.