Quantification And Justice Analysis Of Spatial Distribution Of Urban Green Space Ecosystem Services

On October 18,2017,President Xi Jinping delivered at the 19 th National Congress of the Communist Party of China that a socialism with Chinese characteristics has entered a new era,the principle contradiction facing Chinese society has evolved and what we now face is the contradiction between unbalanced and inadequate development and the people's ever-growing needs for a better life.Promoting a balanced and fair development of society will be an important issue in the new era of socialism with Chinese characteristics.In the city,only by promoting the fairness of public infrastructure,equalization of services,comprehensive development of citizen and social fairness and justice,can all residents enjoy the benefits of modernization.This is not the only way of urban development,but also the primary principle of construction of new urbanization.As an important aspect of environmental research,the justice of ecological environment resources,namely justie of spatial distribution of urban green space ecosystem services,has also attracted people's attention.It is an important indicator of urban environmental sustainability,and it is also one of the aims of National Ecological Garden City,including environmental improvement,economic development and social justice.Since 1980 s,as the important indexes to evaluate the justice of spatial distribution of green space,public green space area per capita,the urban green space area per capita,the ratio of urban green space,urban park area per capita and green space cover ratio were widely tooken by the urban planners and policy-makers.However,in daily life,what people really use and enjoy are ecosystem services provided by the green infrastructure.The ecosystem services can be used as a bridge of landscape spatial performance evaluation,which illustrates the characteristics and functions of landscape space.Quantifying ecosystem services in the community is not only a tool to measure the overall ecological and environmental performance of the community,but also the main means to evaluate the justice of ecosystem services.Therefore,from the perspective of ecosystem services and based on the ecosystem service quantifitive data,this paper analyzes the spatial distribution of urban green space by using Gini coefficient and location entropy.Based on the theories of social justice,this paper takes Qiulin region of Harbin in urban center area as an example.According to the requirements of livable ecological community and ecological problems in Harbin,the multifactor framework integrates five ecosystem components that characterize air purification,carbon storage,noise reduction,cooling and scene beauty,combined with different quantities of resident population in each neighborhood.This paper constructs a quantitative evaluation system of urban green space ecosystem services in Harbin.According to the different types of green space in each community,the ecosystem services are quantified respectively,and the spatial distribution of green space ecosystem services in Qiulin region was visualized by using 23 communities in Qiulin region as quantitative evaluation units.The results can be used as the original data of ecosystem services justice analysis.Then,based on the number of resident population in each community,the social justice of five kinds of ecosystem services provided by 23 community green spaces in Qiulin region are analyzed by using Gini coefficient and Lorenz curve.Analysis of the overall ecological performance of Qiulin region make an evaluation.Due to the differences in the total amount,types and spatial position of green space in each neighborhood of the community,that is,the quantitative criterion of various ecosystem services provided by all types of green space are different,so that the behaviors of spatial distribution of green spaces and their ecosystem services are not share the same conditions.Secondly,the spatial pattern of the ecological performance of the urban green space in Qiulin region are analyzed by using the location entropy.In particular,the community unit with extremely low entropy is classified and analyzed,and three types of communities include:(i)Community with less community green areas.(ii)Community with irrational plants structures of green spaces.(iii)Community units with low ecological performance in the surrounding public green spaces.Finally,in order to solve the problem of unfair distribution of five ecosystem services in each community,combined the evaluation of the overall justice by Gini coefficient and justice performance pattern by location entropy,three kinds of community green space optimization methods are put forward,including:(i)Increasing the total amount of community green spaces.(ii)adjusting the community plants structure.(iii)increasing the number of public green spaces or optimize the original public green spaces.Based on the evaluation of the justice of the spatial distribution of ecosystem services,the improvement of the total amount of ecological services and the justice of the distribution among the units are ensured from two dimensions of whole and unit.Quantifying ecosystem services not only perform multifunction of green spaces,but also plays an important part in determining the dominated function of green spaces in certain regions.Moreover,its use has potential to adjust the composition of green spaces to regulate ecological function,rebuild the community image,and improve the ecological performance in community,especially in the old districts and urban center areas.At the same time,the research methods can provide important reference for city green land system planning.