Environmental Function And Effect Of Ecological Protective Forest On Expressway Of Zibo In Shandong

The thesis aims to study environmental function and domino effect of ecological protective forest on expressway of Zibo of Jinan-Qingdao, Shandong province, emphasis on absorbing dust removal,heavy metal and sulfur dioxide capability of the leaves, combined others'study, layout the proper scheme of planting trees on both sides of expressway which resist pollution. The results of study shows: 1. The density of the total suspended particulate substance and sulfur dioxide in having vegetation on the expressway which are obviously lower than having no vegetation to protect the highway section. It proves the plants have the function of absorbing dust and sulfur dioxide in the atmosphere. 2.The heavy metals in the sections of soil that vegetation protects lower than having no vegetation in the expressway. It can find plant can lighten heavy metal, play better shelter function . 3. Through analyzing, It`s find that dusts of vegetation come from the density of TSP in atmosphere; The sulfur comes from atmospheric SO2 and soil, but the main source is SO2 in the atmosphere; The heavy metal come from the atmosphere mainly, only the content of Cr and Mn have remarkable dependence with the content of Cr and Mn in soil. 4.There are greater differences between the capability of absorbing dust of different types of trees. The amount of dust absorption of the area of unit leaf of the vegetation: Deciduous tree >Bush; The amount of dust absorption of dry weight of vegetation: Deciduous tree >Bush > Evergreen. 5.The content of dust absorption,heavy metal and S of vegetation has reduced as the increase of the distance from the expressway. When from 60 meters of Expressway, the trend of this kind of reduction becomes slow gradually. The change law of absorbing dust,heavy metal and S capability of trees up to season is: high in Autumn and Winter, down in Summer and Spring. 6.There are greater differences between the absorbing dust,sulfur dioxide and heavy metal capability of different types of trees. Synthetically Considering the purification function on the air pollution of trees, can divide the trees into : The first kind of comprehensive absorbability to the air pollution is relatively strong, pagoda tree, Apple, China Savin, Poplar; Second comprehensive absorbability in air pollution strong, such as Deodar Cedar, purple leaf Li, Glossy Privet; The third kind of comprehensive absorbability to the air pollution is medium-sized, such as the cedar , Pear , Evergreen Euonymus , peach, apricot, Huashan pine.