城市公园绿地及周围建成环境对PM_(2.5)的影响--以武汉市10个公园绿地为例

Effects of Urban Park Green Spaces and Surrounding Built Environments on PM_(2.5):A Case Study of Ten Park Green Spaces in Wuhan

城市公园绿地具有较大的生态功能,尤其对PM_(2.5)的消减作用显著,然而当前研究缺乏对公园绿地空间格局及周围环境的考量。以武汉市10个公园绿地为对象,通过实地测量PM_(2.5)数据,从绿地的总体特征、绿色空间格局、周围建成环境3个方面定量分析它们对PM_(2.5)消减的影响。结果表明:(1)公园绿地规模与PM_(2.5)消减量呈显著正相关关系,绿化覆盖率具有潜在影响;(2)公园绿地的绿色空间格局方面,核心、分支越多的绿地,其PM_(2.5)消减量越少,其中核心的贡献度更高;(3)公园绿地周围建成环境方面,最高建筑指数、建筑密度、平均建筑高度、建筑体积密度在5个缓冲区中发挥着对PM_(2.5)消减的相似作用,且对PM_(2.5)的贡献度依次递减,尤其需注重300m范围内这4项指标的管控。从改善大气颗粒物污染的角度,为公园绿地自身的空间格局及周围建成环境的优化调控明确了方向。

Urban park green spaces have great ecological function,especially the significant reduction of PM_(2.5).However,the current research lacks consideration of the spatial pattern of park green space and surrounding environment.Taking 10 park green spaces in Wuhan as examples,through the field measurement of PM_(2.5) data,this paper quantitatively analyzes their impact on PM_(2.5) reduction from three aspects:the overall characteristics,the spatial pattern,and the surrounding built environment of green spaces.The results show that:(1)There is a significant positive correlation between the scale of park green space and the reduction of PM_(2.5),and the green space coverage has a potential impact.(2)In terms of the spatial pattern of park green space,the green space with more cores and branches has less PM_(2.5) reduction,and the contribution of the core is higher.(3)In terms of the built environment around park green space,the highest building index,building density,average building height and building volume density play a similar role in the reduction of PM_(2.5) in the five buffer zones,and their contribution to PM_(2.5) decreases in turn.In particular,attention should be paid to the control of these four indicators within the range of 300m.From the perspective of improving atmospheric particulate pollution,the research has clarified the direction for the spatial pattern of the park green space and the optimal regulation of the surrounding built environment.