基于网络大数据的徐州中心城区绿地空间公平性评价

Evaluation of spatial equity of urban green space based on internet big data for central area of Xuzhou city

城市绿地在美化环境、提升居民生活质量与促进城市可持续发展等方面有重要作用,但当前城市绿地配置时的“被平均”现象已严重违背社会公平与环境可持续发展理念。借助GoogleMap与网络大数据,运用GIS构建城市绿地与小区人口的空间分布,并通过两步移动搜索法测算城市绿地空间可达性供给,在此基础上运用基尼系数与洛仑兹曲线刻画中心城区不同空间尺度下城市绿地的公平性。结果表明:徐州中心城区人均可达性绿地为29.99 m2,总体供给水平较高。小区尺度的绿地分布基尼系数为0.3707,接近警戒线,主要表现为小区以及片区间的绿地不公平。影响绿地空间公平性的因素主要来自两方面:一是城市自然本底条件使绿地分布本身不均;二是城市规划时人口与绿地的空间不匹配导致如老城区及高密度住宅区等的绿地供给水平很低。城市绿地规划建设需要兼顾绿地与人口的空间匹配,尤其减轻土地财政对绿地空间配置的挤压效应,同时还要改进配置决策方式,加强城市绿地规划设计的公众参与。

Urban green space plays an important role in beautifying the environment,improving the quality of residents’life and promoting sustainable urban development.However,the“averaged”phenomenon in the current urban green space allocation has seriously violated the concept of social equity and environmental sustainability.So we study the spatial inequity of urban green space with internet big data skill.GIS technology is employed to construct the spatial distribution of urban green space and community population with the help of GoogleMap and network big data,after that the spatial accessibility of urban green space is measured through two-step floating catchment area method.Based on this,the Gini coefficient and Lorentz curve are used to describe the equity of urban green space in central area of Xuzhou on different spatial scales.The results indicate that:the per capita green space in central area of Xuzhou is 29.99 m2,which is at high level of supply,and Gini coefficient of the green space at community scale is 0.3707,close to the international warning line of 0.4,mainly reflecting the urban green space difference of communities and districts.There are two aspects of factors affecting the equity of urban green space,of which the first is natural heterogeneity of urban land,and the second is that there is no planning power to change the mismatch between population and green space,thus leading to low level of green space supply in old towns and high-density residential areas.This paper argues that urban green space planning and construction need to take into account the spatial matching between green space and population,to reduce the squeezing effect of land finance on green space allocation,and at the same time to improve the allocation decision-making mode and strengthen the public participation in urban green space planning and design.