Eco-environmental Quality Assessment And Ecological Value Of The Loss Evaluation In Highway Construction

In recenet years,with the sustainable and fast development of Chinese economy,expressway,as the most important portion of the highway networks,had been developed at an astonishing fast speed, which brought on increasingly severe ecological environmental problems and great ecological value loss in the mean time.Therefore,It has strategic importance for the coordinated development between the efficiency of social economic environmental and the sustainable development of road construction by estimating the loss of ecological value of highway construction and the evaluating of ecological environment quality of highway constructionEvaluate the ecological environmental quality using composite index,from the biological abundance index,vegetation coverage index,water density index,the index of land degradation, pollution load index on the ecological environment of the study area;at the same time,the ecological value of loss in highway construction of Shenmu-Fugu is estimated from the point of land use.Its conclusions are as follows:(1) Ecological environment quality is relatively poorWe know that ecological environment quality is poor and we also know that there are some major ecological and environmental problems which provide a certain amount of reference for attenting to environmental problems and taking measures in the highway construction process through evaluating the quality of the ecological environment in the study area.Specific situation is:Biological abundance index and vegetation index are relatively high,respectively 54.17 and 86.31;soil erosion index is middle,about 50.41;water density index and pollution load index are relatively low,respectively 3.89,0.39.Taking into account the local specific circumstances and highway construction of their own characteristics,we can know the major problems in study area,that is:the environment in the study area is fragile,at the same time,highway construction has changed the original part of the functions of agricultural land and reduced the amount of land per capita share;at the same time,it will cause a certain amount of demolition,and increase the burden of the relocation of residents,and it also will impact on the relocation of residents of production and lifestyle.On the other hand,a large number of earth and stone will be wachened in the process of highway constructing,which will certainly damage the original vegetation and topography,geomorphology and other natural landscape.In view of these problems,I made some suggestions for reference.①During designing,in order to reduce the use of cultivated land,it can be contracted foot retaining wall to economic use of land;for the natural rivers,try our best not to change the direction of water flow with no compression,plug,blocking rivers;surface water and side ditch water that are poured into a certain region,which can make a complete drainage system,and not pour at either side of the road into the water and soil to prevent pollution of the surrounding soil and water resources.②During constructing,to start with,minimize soil erosion to reduce the adverse effects in larger excavation and filling;what's more,strictly control the volume of excavation,and reinforce excavation of the project,ravine of exposed soil timely,at the same time,plant and protect slope roadbed earthwork project immediately after project completing to resume as soon as possible and ensure to resumpt the vegetation;in addition,field position which is as far as possible to choose wasteland will be to spoil the overall arrangement,and the timely conduct of the spoil compaction,and levele field,in the circumstances permit conditions;at the same time,the pit should be chosen from wasteland and try our best not to the occupation of cultivated land;finally,attent to choose provisional area which is as soon as possible to wasteland and revegetate after project completion.(2) Ecological value loss is relatively largeApart from the construction site,other types of land,such as woodland,grassland,arable land, water and other ecological values are decreased.At the same time the ecological valtie is loss in the study area after highway construction.Specific situation is:Before the highway construction,the value of ecosystem services is 16 978.54 million yuan in the study area,which is less than the later completion value of the area for ecological services that is 16 874.09million yuan.Highway construction completed before than after a reduction in the value of the ecological services is 104.44.In the land use types,grassland loss in the value of the ecological services is most,about 49.21million yuan,which is accounted for 47.12%,and soil and the formation,about 26.93 yuan,which is accounted for 54.72%of the value of the loss in grassland loss,is the largest loss protection in lawn services in the various services.The second loss,about 23.96 million yuan,of the value of the loss is farmland,and the relatively larger loss of the soil farmland ecological services is waste disposal and the protection of formation,accounted for 44.86%.Water loss in the value of the ecological services is 18.86 million yuan,accounted for 18.06%,and the relatively larger loss of the waters of the various services is water conservation and waste disposal,respectively 8.36 million yuan and 7.46 million yuan,accounted for 83.87%.Woodland value of the loss of ecosystem services is 14.01 million yuan,accounted for 13.41%,and the relatively larger loss of the woodland of the various services is the formation and soil protection,gas regulation,biodiversity conservation.water conservation,respectively 2.5 million yuan,2.24 million yuan,2.09 million yuan,2.05 million yuan,accounted for 63.38%.In the land use types, loss in the value of ecosystem services of unused land is list,about 3.56 million yuan,accounted for 26.94%.However,the construction land loss in the value of the ecological services do not reduce,but increase,from 17.33 million yuan to 22.50 million yuan(increasing about 5.17 million yuan).The main reason is:the woodland,grassland,arable land,unused land and waters changed into travel sites(construction land ) after completed and Unit area of construction land in the ecological value is much less than the woodland,grassland,arable land,unused land and waters.