PM2.5 消减效应导向下的城市绿色基础设施网络优化——以湖北省武汉市江汉区为例

城市绿色基础设施（UGI）在缓解PM2.5颗粒物污染及提供其他生态系统服务方面发挥着重要作用。主要依据UGI和PM2.5关联性的既有研究成果，以武汉市典型城区为规划研究对象，构建了基于GIS平台的UGI网络规划实践的空间识别思路，并从提升街区绿地数量与优化绿地形态2个维度提出了基于PM2.5消减的高密度街区UGI优化措施。结果显示：以PM2.5消减为导向，江汉区UGI网络得以优化。其中，绿化覆盖率由23.35%提升至29.96%左右，三维绿量达到约1.15 km2；核心、桥连接占UGI面积的比例分别提升了5.84%、1.15%，孤岛占UGI面积的比例减少了4.32%；江汉区PM2.5消减速率及2018年优良天数均得以提升。首次尝试将PM2.5与绿地相关的理论研究成果应用于UGI规划实践中，提出了以PM2.5消减为导向的城市街区尺度UGI网络优化新思路。

Urban Green Infrastructure Network Optimization Guided by PM2.5 Reduction Effect: A Case Study of Jianghan District, Wuhan City, Hubei Province

Urban green infrastructure (UGI) plays an important role in mitigating PM2.5 particulate pollution and providing other ecosystem services. In the light of the research findings of the research group on the relevance of UGI and PM2.5, this paper takes Jianghan District of Wuhan City as the object to put forward a spatial recognition idea of UGI network planning practice based on the GIS platform. It proposes UGI optimization measures for high-density blocks based on PM2.5 reduction from two perspectives: increasing the number of green spaces in the block and optimizing the form of green space. The results show that the green coverage rate increased from 23.35% to 29.96%, and the 3D green amount reached approximately 1.15 km2; the core and bridge connections increased by 5.84% and 1.15%, and the islets decreased by 4.32%. The deceleration rate of PM2.5 and excellent days in 2018 in Jianghan District were markedly improved. It is the first attempt to apply the theoretical research results related to PM2.5 and green space in block UGI planning, proposing a new idea of urban block-scale UGI network optimization oriented by PM2.5 reduction.