Greater local cooling effects of trees across globally distributed urban green spaces
Greater local cooling effects of trees across globally distributed urban green spaces
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全球分布的城市绿地中的树木具有更大的局部降温效果
DOI：
10.1016/j.scitotenv.2023.168494
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发表时间：
2024
影响因子：
9.8
通讯作者：
Kim J
中科院分区：
文献类型：
--
作者：
Kim J
城市绿色空间是缓解城市热岛效应的有效途径。然而，在全球城市中，当地UGS冷却效果在不同背景气候，植物特征和城市环境中的差异程度还没有得到很好的理解。这项研究分析了来自全球分布的58项已发表研究的265个当地气温（TA）测量值，以推断不同UGS类型（树木，草地，绿色屋顶和墙壁）之间的背景气候，植物和城市变量的潜在影响。我们发现，树木更有效地减少localTA，减少2-3倍以上的草和绿色屋顶和墙壁。我们使用分层线性混合效应模型揭示，背景气候（年平均温度）和植物特征（比叶面积植被指数）对UGS类型的冷却效果影响最大，而城市特征并没有显着影响UGS的冷却效果。值得注意的是，树木在全球城市的整体局部降温效应中占主导地位，这表明在年平均温度较低的温和气候中，树木生长量较大，对UHI的缓解潜力最大。我们的研究结果为使用UGS干预措施缓解城市热量提供了见解，特别是在全球不同气候和环境条件下的城市树木，并强调了树木在极端天气条件下为公民创造健康城市生活环境的重要作用。
Urban green spaces (UGS) are an effective mitigation strategy for urban heat islands (UHIs) through their evapotranspiration and shading effects. Yet, the extent to which local UGS cooling effects vary across different background climates, plant characteristics and urban settings across global cities is not well understood. This study analysed 265 local air temperature (TA) measurements from 58 published studies across globally distributed sites to infer the potential influence of background climate, plant and urban variables among different UGS types (trees, grass, green roofs and walls). We show that trees were more effective at reducing localTA, with reductions 2–3 times greater than grass and green roofs and walls. We use a hierarchical linear mixed effects model to reveal that background climate (mean annual temperature) and plant characteristics (specific leaf area vegetation index) had the greatest influence on cooling effects across UGS types, while urban characteristics did not significantly influence the cooling effects of UGS. Notably, trees dominated the overall local cooling effects across global cities, indicating that greater tree growth in mild climates with lower mean annual temperatures has the greatest mitigation potential against UHIs. Our findings provide insights for urban heat mitigation using UGS interventions, particularly trees across cities worldwide with diverse climatic and environmental conditions and highlight the essential role of trees in creating healthy urban living environments for citizens under extreme weather conditions.