“双碳”目标影响下,公园绿地成为城市生态调控的重要要素之一,其中社区公园绿地对人居空间的“减污降碳,循环发展”有着重要影响。通过海量社区公园的数据筛选,提取绿地空间平面形态、三维形态以及景观格局等方面的6个典型指标,对PM2.5消减量及CO2消减量进行实测研究,分析社区公园绿地微气候环境的形成与维持机制,探讨绿地空间格局对PM2.5与CO2的消减影响。结果表明:不同空间形态绿地指标中,绿地斑块面积、斑块周长以及面积加权形状指数与PM2.5消减量及CO2消减量呈显著正相关; 社区公园绿地斑块面积在1×104~6×104 m2之间时,斑块面积消减作用显著,而斑块面积在6×104~16×104 m2之间时,消减作用减弱; 不同规模社区公园绿地对于PM2.5及CO2的消减边界距离均与斑块面积呈正相关,斑块面积在1×104~2×104 m2之间时,PM2.5最大消减边界在301~303 m之间,CO2最大消减边界在320~381 m之间; 斑块面积在3×104~6×104 m2之间时,PM2.5最大消减边界在474~490 m之间,CO2最大消减边界在470~480 m之间; 斑块面积为10×104 m2及近20×104 m2时,PM2.5消减边界距离分别为560 m及729 m,CO2消减边界距离分别为462 m及803 m; PM2.5与CO2的消减作用呈现出正向协同性,尤其随着斑块面积的增加,协同效应更加显著; 研究成果从城市设计的角度进一步完善城市多尺度空间的绿地景观格局理论,为城市绿地规划的可持续建设提供数据支撑。
Under the background of “double carbon”, community park green space, as a regulatory element of urban ecology, shoulders the target responsibility of “reducing pollution, reducing carbon and developing circularly” in urban space. Through the data screening of massive community parks, six typical indicators of green space plane shape, three-dimensional shape and landscape pattern were extracted, and the reduction of PM2.5 and CO2 was measured. The formation and maintenance mechanism of microclimate environment in community park green space was analyzed, and the influence of green space pattern on the reduction of PM2.5 and CO2 was discussed. The results show that among the green space indicators of different spatial forms, the green space patch area, patch perimeter and area-weighted shape index are significantly positively correlated with PM2.5 reduction and CO2 reduction. When the patch area of community park green space is 1×104-6×104 m2, the reduction effect of patch area is significant, while the patch area is between 6×104-16×104 m2, the reduction effect is weakened. The reduction boundary distance of PM2.5 and CO2 in community parks with different sizes is positively correlated with the patch area. When the patch area is 1×104-2×104 m2, the maximum reduction boundary of PM2.5 is between 301-303 m, and the maximum reduction boundary of CO2 is between 320-381 m. When the patch area is 3×104-6×104 m2, the maximum reduction boundary of PM2.5 is between 474-490 m, and the maximum reduction boundary of CO2 is between 470-480 m. At the large scale of 10×104 m2 and nearly 20×104 m2, the PM2.5 reduction boundary distances are 560 m and 729 m, respectively, and the CO2 reduction boundary distances are 462 m and 803 m, respectively. The reduction effect of PM2.5 and CO2 appear positive synergy, especially with the increase of area, the synergistic effect is more significant. The research results further improve the green landscape pattern theory of urban multi-scale space from the perspective of urban design, and provide data support for the sustainable construction of urban green space planning.