【目的】利用热舒适度评价指标(综合舒适度指标、湿球黑球温度指标)与微气候因子、植物要素的相关性进行微气候效应研究,依据植物景观特征不同的城市滨水绿地中人体热舒适度感受,来提升夏季活动空间的环境品质和使用率。【方法】选取南京内秦淮河城市段上的9个典型样地和1个对照点,在分析场地植物要素(大乔木覆盖率、小乔木覆盖率、灌木覆盖率、地被覆盖率)的基础上,对气象因子(空气温度、相对湿度、风速)进行实测并计算人体舒适度,使用可视化图表反映变化规律,同时研究舒适度与选取因子的相关性。【结果】将滨水空间依据植物平面布局归纳总结为点状、条带状、四周型3种。经过测量分析得到:①点状、四周型布局的空间微气候舒适度较佳,条带状布局的舒适度欠佳,其中点状布局降温增湿效果最显著;②空气温度、相对湿度对微气候综合变量的贡献较大,湿球黑球温度指数指标(wet bulb globe temperature index,WBGT)对舒适度综合变量的贡献较突出,舒适度与空气温度呈显著正相关,与相对湿度呈显著负相关,与风速的相关性最弱;③舒适度与植物要素的相关性从大到小排序为大乔木覆盖率>灌木覆盖率>小乔木覆盖率>地被覆盖率。量化舒适度较优的活动空间植物景观特征,提出在20 m×20 m的城市滨水绿地空间样方内,大乔木与灌木覆盖率比值在(2∶1)~(6∶1)的点状、四周型植物空间布局所反映出的热舒适度值较为适中,配比低于2∶1时对热舒适度值有负面影响。【结论】对不同植物空间布局下的微气候效应进行定量化分析,揭示了各要素的相互作用对夏季滨水绿地空间热舒适度的影响,提出城市滨水绿地空间植物配置的优化策略,即优先采用点状植物空间布局模式改善植物空间对微气候的调节效力,调控大乔木与灌木覆盖率配比大于2∶1来改善城市滨水公共空间的环境品质,灵活选择乔木品种和种植密度,可有效发挥水体与植物的微气候效应。

【Objective】This study explores the correlation between summer comfort evaluation indexes, namely the S index, and wet bulb globe temperature (WBGT) index, and microclimate and plant landscape factors to assess microclimate effects. The goal is to enhance the environmental quality and usability of urban waterfront green spaces by optimizing human thermal comfort under varying plant landscape characteristics.【Method】 Nine representative plots and one control site along the urban section of the Qinhuai River in Nanjing were selected for analysis. Key plant elements (large tree coverage, small tree coverage, shrub coverage, and ground cover) were surveyed alongside meteorological factors (air temperature, relative humidity and wind speed). Comfort levels were calculated, and visual charts were used to illustrate changing patterns. Correlations between thermal comfort and the selected variables were analyzed. 【Result】Waterfront spaces were classified into three plant layout types: point, strip and surrounding layouts. Key findings include the following: comfort variations by layout, namely the point and surrounding layouts exhibited higher microclimate comfort, while the strip layout was less favorable. The point layout demonstrated the most significant cooling and humidifying effects. Contribution of factors to comfort: air temperature and relative humidity were major contributors to the microclimate’s integrated variables, while the WBGT index had a prominent influence on comfort. Air temperature positively correlated with comfort, relative humidity showed a significantly negative correlation, and wind speed had the weakest impact. Plant element correlations: comfort was most strongly correlated with large tree cover, followed by shrub cover, small tree cover, and ground cover. For optimal spatial comfort in 20 m × 20 m quadrats, a large tree-to-shrub coverage ratio between 2∶1 and 6∶1 was ideal. Ratios below 2∶1 negatively impacted the comfort index.【Conclusion】Quantitative analysis of microclimate effects under different plant spatial layouts reveals the interplay of key factors influencing summer thermal comfort. Based on these findings, the following strategies are proposed for optimizing plant configurations in urban waterfront green spaces: prioritize point layouts: Employ point layouts to maximize the regulatory effects of plant spaces on the microclimate. Optimize coverage ratios: ensure a large tree-to-shrub coverage ratio greater than 2∶1 to enhance thermal comfort. Flexible planting strategies: select tree species and planting densities based on site-specific conditions. Leverage water-plant synergy: maximize the combined microclimate benefits of water bodies and vegetation.