Study On Ecological Purification Function Of Camphora And Metasequoia In Major Plains

With the rapid development of urbanization,people’s activities inevitably have a certain impact on the city’s environment.As an important content in the urban green space system planning,the selection and the application of configuration mode of urban greening tree species is not only follow the principle of aesthetics,but also include more ecological concept.Based on the urban road,river greening tree species in Tongxiang as the research object,the comparative analysis is made on the camphor and metasequoia.through the study of these two kinds of trees in the late ability of heavy metals,air pollutant,dust absorption ability,comprehensive evaluation analysis of these two species ecological purification function.Research shows:(1)The accumulation capacity of heavy metals and air pollutants varied with different tree species.Two tree species of heavy metals and atmospheric pollutants accumulation ability is not the same in different environmental conditions.Accumulation of heavy metals of metasequoia and camphor in road greenland are higher than river greenland.(2)The accumulation ability of Pb、Cd、Ni of metasequoia in road and river greenland are hgher than camphor.The accumulation ability of SO2、NOX、fluorid of camphor are higher than metasequoia.(3)Plant different organs of heavy metals and air pollutants accumulation ability is different.All the heavy metal concentration in each organ of metasequoia are higher than camphor.the air pollutant concentration in each organ of camphor are higher than metasequoia.(4)In the road greenland,the order of the concentrations of Pb and Zn in the organs of metasequoia and camphora are:branches> leaves> roots> bark> trunks.The order of Cd concentration is roots> branches,leaves> barks> trunks.While in the river greenland,The order of concentration of three heavy metals in different organs are:roots> branches,leaves> barks> trunks.The air pollutants of different tree species were analyzed statistically that the order of concentration of heavy metals in different organs are:leaves> branches> roots> barks> trunks.(5)The ability of dust retention of different tree species are different.The camphor ’s ability of dust retention is stronger than that of metasequoia.Road greenland is polluted seriously,so camphor dust retention ability is more suited to plant on both sides of the road.