Study On The Relationship Between Plant Community Structure Characteristics And User Satisfaction In Urban Greenways

Urban greenways are an important part of urban green space systems.At present,the planning pattern of most of the cities in China is a fragmented“plaque”shape,which fully promotes the construction of urban greenways that can connect various types of green open spaces within the urban planning area,important natural and human nodes,and various urban green spaces.As a result,the urban greenland ecosystem is complete,and it plays an active role in improving the urban ecological environment and promoting the people’s fitness and leisure activities.It is increasingly concerned by the society and the public.At present,scholars at home and abroad research on urban greenways mostly focus on theoretical research and planning and design.They pay more attention to the layout of green lines,greenway facilities,and greenway materials,and they lack the diversity,health,and green vision of tree species.The urban greenway satisfaction is studied from the perspective of plant community structure,which is the basic element of the urban greenway and is the carrier of its functions in ecology,recreation and landscape.Therefore,this paper attempts to study the urban greenway plant community structure.The degree of satisfaction of features systematically analyzes the factors affecting the satisfaction of urban greenways in terms of plant community structure characteristics,and increases the satisfaction of urban greenway users and the quality of urban greenways from the aspects of plant selection and layout.Based on the research of the relevant literature at home and abroad,this paper has defined the relevant concepts of urban greenways and plant communities and constructed an urban green plant community structural characteristics satisfaction index system,in which the overall structural characteristics,horizontal structure characteristics,and vertical structural characteristics have been used as the guideline and plant health,green looking ratio,tree species diversity,density,plant distribution form,canopy density,trees and shrubs ratio,plant forest form change and forest layer ratio have been considered as indicators.On this basis,the Huangchen Greenway and the Kuanghe Greenway were selected as the research objects.19 samples were selected using the equidistant sampling method,and the area of the sample was determined to be 10*50 m2 based on the characteristics of the green looking ratio.The species,number,height,diameter at breast height,crown width,and health condition of trees and shrubs in the sample field were then recorded through field survey sample.In addition,species name,coverage,type and growth condition of herbaceous layer were recorded.The main configuration of the plant community were also recorded and a floor plan were plotted then（Appendix C）.The relative abundance,relative frequency,relative significance,relative coverage,important value,density,and diversity index（Shannon-Wiener index）,canopy density,trees and shrubs ratio,evergreen and deciduous tree ratio,forest layer ratio,green looking ratio is calculated according to the structure characteristics of the plant community.With the questionnaire survey method,spss23.0 statistical software was used to analyze the relationship between user statistical characteristics and satisfaction,the overall structure of plant communities and satisfaction,level of structural features and satisfaction,vertical structural characteristics and satisfaction,to explore the satisfaction of the urban greenway plant community structural characteristics.The results show as follows:（1）There are 41 species of Huanchen Green Road samples,belonging to 29families and 38 genera.Among them,18 species of evergreen tree species and 23deciduous tree species indicate that the main tree species are deciduous tree species in the Huanchen greenway.There are 46 species of plants in Kuanghe greenway quadrats,belonging to 25 families and 36 genera.There are 21 species and 25 species of evergreen and deciduous trees respectively.The diversity of the tree layer diversity Shannon-Weiner index（2.73）of the Huanchen greenway is smaller than that of the Kuanghe greenway Shannon-Weiner index（2.78）,and the Shannon-Weiner index of the shrub layer of the Kuanghe greenway is higher（2.81）than the Shannon-Weiner index of the shrub layer of the Huanchen Green Road（2.11）.The utilization rate of Huanchen Green Road native tree species（56.1%）is higher than that of Kuanghe greenway（47.8%）,and the local tree species allocation of Kuanghe greenway should be strengthened to highlight zonal characteristics.（2）In the 19 quadrats,plant communities are diverse,and the community structure is mainly composed of trees,shrubs and herbs.The green viewing rate of quadrats is relatively high,ranging from 32.18%to 72.53%.The Huanchen greenway Shannon-Wiener ranges from 1.09 to 2.18,and the range of the Kuanghe Green Road sample is 0.39¹.93,and the tree species allocation of Kuanghe green road is more diversified.The plant density ranged from 540²200/hm2.Most of the plants in Kuanghe greenway are artificially planted,and they are evenly distributed.The greenbelt plants around the Huanchen greenway are randomly distributed.The completion time of the Huanchen greenway is longer than the Kuanghe green road.The 0.65⁰.92 of the plants in the sample is higher than the Kuanghe Green Road（0.2⁰.69）,and the health degree is lower than the Kuanghe green road.The degree of seasonal variation of the two greenways is quite different.（3）The population of different greenway plots used varied in gender,age,occupation,academic background,occupational transport mode and motivation since the occupation.The user’s age,educational background,and transportation methods to and from this place are significantly related to satisfaction.There was no significant correlation between the user’s gender,occupation,motivation and satisfaction.Most of the users use frequency once a week,the frequency is high,and the willingness to recommend is also very strong.（4）The overall level of satisfaction of the Huanchen greenway and the Kuanghe greenway is generally fair.The satisfaction scores of the 19 samples surveyed ranged from 3.211 to 4.519.There were 12 satisfaction levels below the satisfaction level and 7 above the satisfaction level.There is a quadratic or cubic curve relationship between the 8 indicators and the satisfaction degree of the plant community structure characteristics of the urban greenway.There is no curve relationship between the plant distribution pattern,the regression analysis of the species ratio and satisfaction of the arbor evergreen deciduous trees.（See Table 4-27,Table 4-29,and Table 4-31 for details.）The relational expressions are:（1）Plant health S₁=-7.087+4.54C₁-0.436C₁²（2）Green Looking Ratio S₂=3.060+0.063C₂-6.493*10^-7C₂³（3）Tree diversity Shannon-Weiner index S₃=2.703+1.305C₃-0.0202C₃²（4）Density S₄=2.729+0.001C₄-1.515*10^-7C₄²-1.056*10^-10C₄³（5）Crown density S₆=2.091+8.89C₆-15.657C₆²+7.710C₆³（6）The ratio of trees to shrubs S₇=3.790+1.443C₇-0.98C₇²+0.151C₇³（7）Number ratio of evergreen deciduous trees in ArborS₈=3.807+0.288C₈-0.202C₈²+0.029C₈³（8）Forest layer ratio S₁₀=2.118+10.63C₁₀-16.782C²₁₀+7.664C³₁₀（5）Through the multiple linear regression model of the influencing factors and satisfaction,the results showed that when the plant community health and tree diversity index were between 3.5⁵ and 1²,the green sight rate and the evergreen deciduous number ratio of trees were between 25%³0%and 1:1¹.2:1 respectively,the density was about 1500/hm² and the canopy density was about 0.42.When the forest layer ratio is above 0.5 and the distribution is reasonable,the satisfaction degree of urban greenway plant community structure is the highest.