Discussion on Several Problems of Expressway Virescence

According to the fundamental principles of ecological virescence and ecological restoration,certain problems of domestic expressway virescence were discussed.Analysis demonstrates that there are some inaccurate cognition in aspects of the landscape virescence of expressway,the structure of vegetation community,the extrinsic vegetation and the virescence on excavation slope.It was pointed out that the essential function of expressway virescence is to protect ecosystem,hence the landscape virescence of expressway must follow the basic regularity of ecological restoration.That is to say,during the process of landscape greening in expressway the heterogeneity of vegetation community in vegetation species structure,time-space character and nutrition structure should be assured;what is more,the restrictive principle should be followed while introducing extrinsic vegetation,and the principles of keeping the stabilization of slope,conserving soil and water,renewing nature,adapting condition and harmonizing with landscape in the virescence design of excavation slope should also be followed.The dynamic effect of virescence should be considered in the evaluation of landscape virescence of expressway and function of transport,and the dynamic effect of some sections of a highway should be checked by dynamic vision analysis.