Classification Of Micro-site Types And Site Quality Evaluation Of Expressway Slopes In Central And Southern Shandong

The site conditions of expressway slopes are different due to the different factors such as the large area span and micro-geomorphology of highway slopes.Taking the same ecological restoration measures for highway slopes with different site conditions can easily lead to poor plant growth and poor long-term results.The classification and evaluation of site types of highway slopes can provide pertinent and scientific theoretical basis for vegetation restoration of slopes.Through field investigation UAV aerial photography and indoor analysis,site factors are selected by using difference analysis and principal component analysis,site types are classified by cluster analysis,and the site types are named by using dominant factors to form a site type system of highway slope in hilly areas of middle-south Shandong Province.On this basis,combining the analytic hierarchy process and expert scoring to evaluate the quality of the site.The results are as follows:(1)Through field investigation and data analysis of 66 Expressway Slopes in the study area,the Expressway Slopes in hilly areas of central and southern Shandong Province are divided into 5 site types and 25 micro site types.5 site types are:soil embankment slope,soil cutting slope,soil-rock embankment slope,soil-rock cutting slope,rock cutting slope.Among them,the soil embankment slope is divided into 3 micro-site types:Medium-long shady slope in medium-thick soil layer,medium-long sunny slope in thin soil layer and short-shady/sunny slope in thick soil layer;Soil cutting slope is divided into 4 types of micro-site:medium-hard steep shady slope,medium-hard steep sunny slope,relatively hard steep shady slope and soft sunny slope;soil-rock embankment slope is divided into 5 types of micro-site:medium-hard short shady slope,relatively hard short sunny slope,soft medium-hard long sunny slope,medium-hard long sunny slope and relatively hard long shady slope.Soil-rock cutting slope can be divided into 4 types of micro-site:medium-rough and steep shady slope,smooth sunny slope,rough and steep sunny slope,rough and sharp shady slope;rock cutting slope can be divided into 9 types of micro-site:steep and slight weathering short shady slope,steep and weak weathering long sunny slope,steep and slight weathering short sunny slope,steep and slight weathering short shady slope,steep and slight weathering long sunny slope,steep and slight weathering medium and long shady slope,dangerous and strong weathering short shady slope,dangerous and dangerous.The slightly weathered super-long sunny slope and the dangerous slightly weathered long shady slope.(2)By evaluating the site quality of the slope,it is concluded that 16.7%of the sample sites in the soil embankment slope are of medium level,and 83.3%of the sample sites can reach good level.The site conditions of 66.7%of the soil cutting slopes are good,and the site conditions of the two sites are of medium level.The site conditions of all sample sites in the slope of soil-rock embankment can reach a good level.The site conditions of 11.1%of the soil-rock cutting slopes are of medium level,and 88.9%of the sample sites can reach a good level.The site conditions of 54.8%of the rock cutting slopes can reach a good level,and 45.2%of the sample sites are of medium level.Suggestions for vegetation restoration were put forward according to site conditions.