Configuration Modes Research Of Avenue Trees Based On Sunlight Analysis In Zhengzhou City

Street greening is an important part of urban greening Avenue tree is the main body to construct the urban green space network structure and the name card of the city's external image.lt is of great significance for the development of urban landscape to study the selection of tree species and determine the volume and configuration modes of avenue trees.This study took zhengzhou city as an example.Firstly 20 typical streets samples in different directions and types were taken as research objects,and the width of the streets,the height of buildings on bath sides of the streets,the avenue trees species,the height,the crown and diameter of the avenue trees were investigated.On the basis of field investigation,this paper drew on the method of sunshine analysis in the construction industry,and made a comparative analysis of avenue trees' getting sunlight time.Secondly this paper took specific values to control the variables(street width,height of buildings on both sides of the street,height of trees),used SketchUp software to establish models and calculate quantitatively,studied the getting sunlight time of avenue trees in east-west and south-north streets in various combination of variables.The results showed that,the difference between the maximum time and the minimum time which avenue trees could get sunlight on different east-west streets was significant.The maximum time and the minimum time which avenue trees on north side could get sunlight were both longer than that on south side.There was the time difference between 2h to 7h.The difference between the maximum time and the minimum time which avenue trees could get sunlight on different south-north roads was significant.There was almost no difference between the maximum time and the minimum time of avenue trees could get sunlight on east side and west side.When the street width and the height of avenue trees were certain,the getting sunlight time of avenue trees decreased with the increase of the building height on both sides of the street.When the the street width and the height of the building on both sides were certain,the getting sunlight the of avenue trees increased with the increase of height of avenue trees.This paper took zhengzhou city as an example and discussed the avenue trees configuration modes according to the investigation of tree species and volume.Streets wider than 40 meters should be planted with large-volume street trees such as Sophora japonica,Platanus acerifolia,Populus tomentosa and so on.On the streets with width of 20?40 meters,when the roadside buildings were low-rise,multi-storied and middle-high buildings,it was advisable to plant medium-volume street trees such as Ligustrum lucidum,Fraxinus chinensis and so on,When the roadside buildings were high-rise buildings,it was advisable to plant large-volume street trees.On the streetwith width less than 20 meters,when the roadside buildings were low-rise and multi-storied buildings,it was advisable to plant small-volume and medium-volume street trees such as Eriobotrya japonica,Prunus cerasifera,Ligustrum lucidum,Fraxinus chinensis and so on.When the roadside buildings were multi-storied,middle-high and high-rise buildings,it was advisable to plant medium-volume street trees.And the paper selected Zhongyuan middle road and Bitao road optimized scheme design,so as to provide certain reference for street greening of Zhengzhou city.