Survey And Analysis On Situation Of Street Trees Greening In Xincheng District Of Xi’an City

Street trees is the core of urban greening, selecting species of green tree is the mostbasic part of the system, which determines whether the ecological, landscape and socialbenefits of urban greening can fully play effective and efficient. Scientific selection of treespecies has important theoretical and practical significance on improving the quality ofurban ecological environment and achieving cities’sustainable development.With the rapid development of social and economic, Xi’an is also faced with airpollution, noise and other environmental problems. The important and effective way tosolve these problems is vigorously carrying out urban greening. In this paper XinchengDistrict is taken as a representative area of Xi’an and divided into the eastern suburbs,northern suburbs and inner suburbs, which are used as the study area. By survey, thepollution status of roads’ surrounding and the status of street trees’ application in eachsuburb are found out. The problem of street trees’ greening in Xincheng District isinvestigated. In connection with tree species in Xincheng District, several typical streettrees are selected to analyze the benefit of management, which aims to bring suggestionsfor the problem and solution of street trees’application in Xincheng District.Survey results in Xincheng District show that more than30species of street trees areexisting and the total number is20227. The green area is209066.3m2and green coveragearea is1138583.2m2. According to the number of streets trees, different types aredescribed as follow: Fatong, Sophora japonica, Ligustrum, Mao Yang, Acer mono, poplar,paulownia, Neem, weeping willow, walnut, ash, silk, black locust, catalpa tree, Ligustrum,oil tree, triangle maple, toon, thorn cypress, cedar, persimmon, pomegranate, fig trees,cherry, willow.. In addition, there are425different types.The survey results on roads’ surrounding show that the street trees in the easternsuburbs area are plane tree, Chinese white poplar, Acer mono, Chinese ash, locust, and theglossy privet; the street trees in the northern suburbs are Sophora japonica, Chinese whitepoplar, paulownia, glossy privet, black locust, which mixed a part of different types; the street trees in inner suburbs are mainlyAcer mono and Sophora japonica.Analysis of existing street trees’ influence on contaminants shows that street trees inthe eastern suburbs of Xincheng district can’t fully control the pollution of noise, sulfurdioxide, hydrogen fluoride gas.etc; street trees in the northern suburbs can’t fully controlthe pollution of noise, the battery industry and medicine wastewater; the type of street treesin inner suburbs is simple, which can’t play a role in controlling pollution of the road.Therefore, the mainly problem exists as follow: the species is single, the distribution isuneven, choose of species is inappropriate, native species have not been fully utilized,conservation and management are very backward. The relevant trees should be changed.To understand the management efficiency of Xincheng distinct Xi’an, ten kinds oftypical trees are chosen to be analyzed. The results show that the overall efficiency ofwalnut tree is best, which is followed by neem and benefit-cost ratio of poplar is lowest.Considering the economic, the input-output ratio of poplar and other species used inXincheng distinct is low and the overall efficiency is poor. So it is recommended to use awalnut tree and other economic species.It is also recommended to develop cultivation of fruit trees based on the the regionalcharacteristics, which can adapt to the need of developing urbanization and economicconstruction for new green, colorful, cost-effectiveness species. But it need to follow thescientific principles, base on the objective reality, configure different types of treesreasonable, bring the superiority of variety of species into full play.