城市公园绿地可达性与社会公平性研究

Accessibility and social equity of urban parks

【目的】研究城市公园绿地的可达性与社会公平性,为提升公园绿地质量、保障弱势群体环境正义提供科学依据。【方法】以杭州市上城区公园绿地为研究对象,通过获取手机信令、大众点评、兴趣点(POI)等多源大数据,组建数据库,引入公园质量评价结果、吸引力算法和高斯衰减函数,改进两步移动搜索法,计算步行和公共交通模式下居住小区老龄人口获取公园绿地的可达性值,并利用Pearson相关系数分析公园绿地的社会公平性差异及其成因。【结果】(1)上城区各类公园质量存在较大差异,综合得分高于平均值的公园绿地占21.37%。(2)不同交通模式下的可达性程度差异较大,步行模式下65.98%的居住小区可达性值极低,而公共交通模式下可达性值极低的小区占33.81%;随着时间阈值的增大,可达性均出现高值扩散、低值消退的趋势;2种交通模式可达性均呈现集聚分布,公共交通模式下集聚程度更高。(3)上城区公园绿地存在社会不公平现象,步行模式下不公平程度最高,公平性低值达74.8%;叠加分析显示:不公平区域集中在上城区中部,呈片状分布。【结论】公园绿地供给与老龄人口需求之间存在不公平现象。将来,在城市绿地规划建设时应提升现有公园绿地服务质量,完善交通网络,适度增加绿地数量和改善小区居住环境。

[Objective]To study the accessibility and social equity of urban park green spaces,and provide scientific basis for improving the quality of park green spaces and ensuring environmental justice for vulnerable groups.[Method]The park green spaces in Shangcheng District,Hangzhou City were chosen as the research object.By obtaining multi-source big data such as Mobile Signaling,the Public Comment,point of interest(POI)and so on,a database was constructed.The results of park quality evaluation,attraction algorithm,and Gaussian decay function were introduced to improve the two-step mobile search method,calculate the accessibility value of the elderly population at the residential community level to access park green spaces under the walking and public transportation modes.The Pearson correlation coefficient was used to analyze the differences in social equity and their causes.[Result](1)There were significant differences in the quality of various types of parks in Shangcheng District,with 21.37%of park green spaces scoring higher than the average.(2)There were significant differences in accessibility levels among different transportation modes,with 65.98%of residential areas having extremely low accessibility levels under walking mode,while 33.81%had extremely low accessibility levels under public transportation mode.As the time threshold increased,there was a trend of high value diffusion and low value fading in accessibility.The accessibility of both types of transportation modes showed a clustering distribution,with a higher degree of clustering under public transportation modes.(3)There were social inequality in the park green spaces of Shangcheng District,with the highest level of unfairness in the walking mode,with a low fairness value of 74.8%.Overlay analysis showed that unfair areas were concentrated in the central part of the upper urban area,with a patchy distribution.[Conclusion]There is an imbalance between the supply of park green spaces and the demands of the elderly population.In the future,it is anticipated that during the planning and construction of urban green spaces,the quality of existing park green space services will be improved,transportation networks will be enhanced,the number of park green spaces will be moderately increased,and the living environment of residential communities will be improved.