ABSTRACT
In the process of road development, the change of vegetation situation on both sides of the road gradually becomes more important. Taking Lipu-Yulin Expressway in Guangxi Province as the research area, this study takes NDVI as the research object to indicate the vegetation change during 2014 to 2019. The results of the analysis on buffer zone, situation, spatial change trend of vegetation characteristics show that: the vegetation within the 1 km buffer zone on both sides of the expressway is the focus of attention in the early stage of construction; the vegetation within 3 km buffer zone shows a downward trend as a whole; the vegetation within 5 km buffer zone shows a good trend as a whole. The multi-year average NDVI values of 1 km, 3 km, and 5 km buffer zones are respectively 0.796, 0.796, and 0.799. The vegetation in the 5 km buffer zone is significantly better than that in other groups. The vegetation change trend in the 1 km and 3 km buffer zones is getting worse, and the corresponding vegetation change will not improve until it is expanded to 5 km. This study provides thinking for the vegetation management and protection in the early stage of expressway construction in karst areas, and puts forward suggestions for the effective restoration of vegetation guided by green development and ecological environmental protection in the next step of expressway construction.
