Ecological impact assessment method of highways in Tibetan Plateau:A Case study of Gonghe-Yushu Expressway

In recent years,the ecological environment along highways in Tibetan Plateau has been severely affected due to the rapid construction of highways.In order to solve the problems of multiple indicators and inconsistent criteria in the ecological impact assessment of highways,and to scientifically screen assessment indicators,the paper proposes a multi-round indicator screening method,which combines literature analysis,expert rating,and statistical analysis.Based on this screening method,normalized difference vegetation index,land surface temperature,elevation,and normalized difference soil index are screened out.Combined with multiple linear regression,an ecological impact assessment model is established and applied to ecological impact assessment of Gonghe-Yushu Expressway.The results show that the expressway construction is the first driving force for the deterioration of the ecological environment along the roadside,and its interference range on the desert grassland ecosystem is greater than that on the agroforestry system.The ecological environment within 150 m on both sides of the expressway should be protected.

Research and Analysis of Regional Ecological Positioning in Planning Environmental Impact Assessment

The regional ecological positioning of one area is based on the region’s ecological orientation by the country or a larger region.Combined with the region’s natural geographical features,ecological background,main ecological problems,regional ecological structure,pattern,process,function and service,etc.,the position of a certain area in ecological space,structure,process,function and service,etc.is determined through the analysis and research.Regional ecological positioning is an important prerequisite and core basis for regional ecological impact assessment.However,in the current regional ecological impact assessment,most of them have not analyzed and studied the regional ecological positioning.Due to the lack of research on regional ecological positioning,it is rare to apply the research results of regional ecological positioning to the establishment of regional ecological objectives and the construction of index system.Regional ecological positioning does not guide the direction of regional ecological protection and construction well,and there is a general tendency of regional ecological positioning being one-sided and slogan-based.This paper analyzes the necessity and importance of research of regional ecological positioning,puts forward the technology framework of study on regional ecological positioning.With regional ecological positioning research in planning ecological impact assessment of the Chengdu-Chongqing Economic Zone as an example,how to carry out the study on the regional ecological positioning and how to apply the results of the study on the regional ecological positioning in regional ecological impact assessment are explained and illustrated.