Application Status Of Plant Species On Streets And Parks Of Shenzhen And Building Models For The Common Tree Species In The City

According to the approval of the State Council of Shenzhen City Master Plan(2010 ~ 2020),this paper takes the urban road and park green space in Shenzhen city as the research object,and makes an in-depth investigation and analysis of its construction in the planning period,so as to provide guidance for the realization of the planning goal.Using the method of checking and selecting the typical sample,we selected 176 plots,the road and the park were 85,91.This paper analyzes the present situation and influencing factors of plants and the vertical structure of the community in urban and parks greenbelt in Shenzhen.This paper explores the relationship between community canopy density and community vegetation growth status;analyzes the height and diametric of broad-leaved trees in the optimal community to understand the dynamics of community growth;constructes the common broad-leaf trees growth model in Shenzhen garden application.The results show that:(1)There were 189 plants(varieties)in the road green space,including 102 kinds of trees,57 kinds of shrubs,30 kinds of herbs in the this survey,species proportion of tree and shrub 1.79: 1.There were 221 plants(varieties)in the park green space,including 129 kinds of trees,56 kinds of shrubs,36 kinds of herbs in the this survey,species proportion of tree and shrub 2.3: 1.There are 66 species of native plants in the road green land,accounting for 34.92% of the total species.which include 3 kinds and 8 ancient trees,Ficus microcarpa,Bombax ceiba,Cinnamomum platyphyllum.There are 78 species of native plants in the park green land,accounting for 41.27% of the total species.which include 6 kinds and 13 ancient trees and a unique coastal native plant community,Litchi chinensis,Ficus microcarpa,Crateva religiosa,Ficus altissima,Osmanthus fragrans,Ceiba pentandra.The two types of greenland native plant species are lower than the construction of ecological garden in the native plants accounted for 70% of the standard.There are more than 30 kinds of broad prospects for the application of wild ornamental plants worthy of promotion,such as Michelia doltsopa,Michelia odora.In the next few years of construction,it is proposed to increase the proportion of native trees,to further enrich the diversity of plants and landscape.Reasonable development of the application of ancient trees,especially banyan,kapok,can create a green tree characteristics of the tree.Strict implementation of the protection of existing mangrove wetlands,maintenance and create a suitable ecological environment.(2)Plant species in the road green space,belonging to 65 families and 123 genera,and three large branches were Arecaceae,Fabaceae,Myrtaceae,respectively.Plant species in the park green space,belonging to 67 families and 92 genera,and 4 large branches were Arecaceae,Fabaceae,Moraceae,Euphorbiaceae,respectively.In recent years,city road and park greening in Shenzhen more and more attention to the high value of the use of Fabaceae.The ratio of evergreen tree species to deciduous tree species in road plots was 1: 0.189,and1:0.249 in park green space.Greening mainly evergreen tree species,it is recommended to increase the application of deciduous tree species,increase the seasonal change.(3)The period of the larger amount flowers of green landscape were May-September in Shenzhen Road.Green land on January-March were mainly to Coriaria nepalensis,Bauhinia blakeana and other red flowers and Senna surattensis,Lantana camara and other yellow-based flowers.On April-August months were to red,white,yellow as the main colors,opening the safflower wre Delonix regia,Verbascum thapsus,Hibiscus rosa-sinensis,etc.,opening white flowers wre Murraya exotica,Aglaia odorata,Hymenocallis littoralis,Michelia alba,opening yellow flowers wre the main Hibiscus rosa-sinensis var.rubro-plenus,Wedelia chinensis,etc.On September-December mainly in red(Coriaria nepalensis,Verbascum thapsus,Jatropha pandurifolia)and yellow(Lantana camara,Cassia bicapsularis)for the main colors.Green landscape flowers spend a large period of time mainly concentrated in the May-September in park.On October to the following year in May wre mainly red(Hibiscus rosa-sinensis,Jatropha pandurifolia,Bombax ceiba,Spathodea campanulata),yellow(Handroanthus chrysanthus,Dillenia turbinata,Osmanthus fragrans,Mangifera indica),white(Bauhinia variegata var.candida,Elaeocarpus rugosus,Gardenia jasminoides)colors,June-September wre mainly in white(Michelia alba,Jasminum sambac,Tabernaemontana divaricata),yellow(Senna surattensis,Aglaia odorata,Allamanda cathartica),red(Nerium indicum,Hamelia patens,Hibiscus rosa-sinensis)colors.At the same time,Lagerstroemia speciosa and Thevetia thevetioides,Lagerstroemia parviflora in full bloom,adding purple and pink.in recent years Shenzhen use large-scale of Hibiscus rosa-sinensis var.rubro-plenus,Lagerstroemia glabra,Ixora javanica and other flower bush,to improve the landscape effect.There were less fruit trees used in road,only Syzygium fluviatile,Mangifera persiciforma,Alstonia scholaris,Ficus altissima and so on.There were more fruit trees used in park green space,mainly Litchi chinensis,Dimocarpus longan,Kigelia africana,Dillenia turbinata,Mangifera indica and so on.(4)The higher importance of arbor layer of vegetation community in road green trees is Livistona chinensis,Roystonea regia,Falcataria moluccana,Khaya senegalensis.The higher importance of shrub layer is Excoecaria cochinchinensis,Bougainvillea spectabilis,Ficus microcarpa'Golden Leaves',Hibiscus rosa-sinensis var.rubro-plenus,Ixora chinensis.The higher importance of herb layer is Wedelia chinensis,Axonopus compressus,Neomarica gracilis,Hymenocallis littoralis,Zoysia tenuifolia.The higher importance of arbor layer of vegetation community in park green trees is Litchi chinensis,Roystonea regia,Falcataria moluccana,Ficus parvifolia,Lagerstroemia speciosa.The higher importance of shrub layer is Osmanthus fragrans,Brunfelsia acuminata,Excoecaria cochinchinensis,Rhododendron × pulchrum,Ficus microcarpa'Golden Leaves'.The higher importance of herb layer is Axonopus compressus,Sphagneticola calendulacea,Zoysia tenuifolia,Neomarica gracilis,Alocasia odora.The two types of green space in the top ten species with the same climate than the city are different trees but shrub layer and herbaceous layer plant species are not very different.(5)In terms of species richness,the tree greenbelt and the shrub layer richness index,Simpson Diversity index,Shannon-Wiener Diversity index,Uniformity index of the road greenbelt are 13.971,8.332,0.931,0.903,2.123,1.094,0.459,0.271 respectively.the tree greenbelt and the shrub layer richness index,Simpson Diversity index,Shannon-Wiener Diversity index,Uniformity index of the park greenbelt are 17.536,8.444,0.95,0.934,2.525,1.321,0.521,0.328.The richness indexes of the two types of green plants are higher,the plants are abundant,but the evenness index is not high,the plant distribution is not uniform.(6)There were 12 vertical structures in the survey area,and the most of them is upper medium tree + shrub + ground + lawn,accounting for 23.53% of the total squares,The vertical structure of green plants is mostly five or more layers;Park green space community is relatively rich in vertical structure,here were 18 vertical structures,of which the most vertical structure for the trees is upper medium tree + shrub + ground + lawn,accounting for 20.88% of the total square number.Plant vertical structure in road green is rich in Shenzhen city.(7)There was a significant correlation between the growth status of the community and the overlap of the community,the total canopy density and the upper canopy density.When the total canopy density,overlapping canopy density and upper canopy height were 70%,20% and 40% respectively,the community had higher ecological efficiency,and the plant growth status was higher than that of 80%.(8)In road green space the broad-leaved trees with the DBH of less than 10 cm and the height of less than 10 m were 46.57% and 51.52% of the total number of broad-leaved trees respectively,in park green space,respectively,the total number of 32.99%,50.27%.Community broad-leaf trees have enough growth space,the community belongs to the growth type.With the growth of plants,it is necessary to manually adjust the canopy density,so that the plant growth rate of about 80% of the community canopy closure,promote the virtuous circle of the community.(9)Based on the significant correlation between crown width and DBH of broad-leaf trees,a total of 67 species of broad-leaved tree crown-DBH growth model are first constructed to provide a reference for determining the appropriate planting density.