Construction Domain Of Highway In Qinling Mountains Based On Principal Component Analysis Ecological Impact Study

The destruction of ecological environment along the mountain expressway construction project has been widely concerned.In order to coordinate the contradiction between highway construction and mountain area ecological environment protection,we should deeply study the impact of highway construction on the ecological environment of the road area,identify the key elements of the ecological impact of the road area,put forward scientific and reasonable suggestions on ecological protection and restoration of the road area,and incorporate the ecological environment protection of the road area into the highway construction project.To maintain the sustainable development of ecological environment in the road area is a key link.First of all,through the method of combining theoretical analysis and field research,three criterion level indexes including project construction intensity,ecological impact degree and landscape restoration intensity were selected.There are 11 factor level indexes including excavation and fill balance rate,bridge and tunnel ratio,temporary land area ratio,permanent non-construction land area ratio,forest and grass vegetation loss rate,agricultural vegetation loss rate,newly increased soil and water loss rate,temporary land ecological restoration rate,vegetation restoration rate,green coverage rate,and total control degree of soil and water loss.According to local conditions,a multi-dimensional and multi-level ecological impact evaluation index system of highway construction in Qinling Mountain area is constructed.Secondly,the method of principal component analysis(PCA)is used to establish the ecological impact assessment model of highway construction in Qinling Mountain area.The empirical analysis is carried out based on eight expressways with similar natural environment that traverse the southern foot of Qinling Mountains.Finally,the empirical results were analyzed and discussed in depth,and the key factors affecting the ecology of highway area in Qinling Mountain area were identified: the forest and grass vegetation loss,excavation and fill balance rate,bridge and tunnel ratio were the factors most likely to have an impact on the ecology of highway area.The ratio of permanent occupied non-construction land area,the ratio of temporary project area,the amount of agricultural vegetation loss,the amount of soil and water loss added during construction,and the ecological restoration efficiency of temporary project are relatively easy to have an impact on the road ecology.After the completion of the main expressway project,the vegetation restoration,green cover and soil erosion control have a certain positive impact on the highway ecology.According to the key factors of ecological impact of highway construction in Qinling Mountain area,the paper puts forward three more targeted suggestions on ecological environmental protection and restoration of highway construction in Qinling Mountain area,including control of ecological resource occupation,improvement of ecological restoration efficiency and ecological restoration,so as to promote the harmonious integration between highway construction and environmental protection in Qinling Mountain area.