Urban Agriculture Research Division, National Institute of Horticultural and Herbal Science, Wanju 55365, Republic of Korea.
Int J Environ Res Public Health. 2023 Jan 31;20(3):2507. doi: 10.3390/ijerph20032507.
Street trees are crucial for air pollutant reduction in urban areas. Herein, we used computational fluid dynamics (CFD) simulation to identify changes in airborne particulate matter (PM) concentration based on wind characteristics (direction and velocity) and the green network of street trees. The green network was assessed based on composition of the green area of street trees in the central reserve area and between the motor and pedestrian roads. The PM concentration varied according to the presence or absence of major reserve planting and the planting structure of the street trees, but not according to the wind direction or velocity. The concentration was lower when the wind direction was 45° (than when the wind direction was 0°), whereas it showed a more significant decrease as the wind velocity increased. Despite variation at each measurement site, the PM reduction was generally higher when the central reserve and street trees had a multi-planting structure. Hence, to ensure an effective reduction in the PM concentration on motor roads and reduce its negative impact on pedestrians, both arbors and shrubs should be planted in the central reserve area. The study results will serve as reference for managing the green area network and linear green infrastructure in terms of improving the atmospheric environment.
街道树木对于城市地区减少空气污染物至关重要。在此，我们使用计算流体动力学（CFD）模拟，根据风的特征（方向和速度）以及街道树木的绿色网络，来确定空气中颗粒物（PM）浓度的变化。绿色网络是根据中央隔离带和机动车道与非机动车道之间的街道树木的绿地组成来评估的。PM 浓度根据主要预留种植和街道树木的种植结构的存在与否而有所不同，但与风向或风速无关。当风向为 45°时（比风向为 0°时），浓度较低，而随着风速的增加，浓度下降更为显著。尽管在每个测量点都存在变化，但当中央隔离带和街道树木具有多种植结构时，PM 减少的幅度通常更高。因此，为了确保机动车道上 PM 浓度的有效降低，并减少其对行人的负面影响，应在中央隔离带种植乔木和灌木。本研究结果将为管理绿色区域网络和线性绿色基础设施提供参考，以改善大气环境。
