Investigating the Role of Vegetation and Old Trees in the Walls of Urban Streets on the Range and Thermal Comfort of Pedestrians.

Fatahi, Karen

doi:10.22077/jdcr.2025.8907.1117

Investigating the Role of Vegetation and Old Trees in the Walls of Urban Streets on the Range and Thermal Comfort of Pedestrians.

Document Type : Original Article

Author

Karen Fatahi

Assistant Professor, Department of Architecture, Ilam Branch, Islamic Azad University, Ilam, Iran.

https://doi.org/10.22077/jdcr.2025.8907.1117

Abstract

This study compares the effect of trees on the thermal comfort of pedestrians in urban streets with and without trees. This study used a survey and field method to investigate the effect of removing old trees and vegetation (boxwood, grass, and flowering shrubs) on the thermal comfort of pedestrians in four streets of Ilam. The statistical population consisted of 384 people (96 people per street) who were selected by simple random sampling. Data were collected using the American ASHRAE-55 standard questionnaire for subjective assessment of thermal comfort and MIC98586 data logger tools for recording climatic variables, Fluke 975 Air Meter for recording CO₂ concentration values, and TES1326 laser thermometer for recording skin surface temperature. Then, the data were analyzed using Pearson correlation and multivariate linear regression in SPSS27 software to examine the relationship between climatic variables and thermal comfort. The findings showed that the mean and standard deviation of the thermal comfort status of pedestrians for the treeless streets of Taleghani and Samandari are 0.52 ± 0.049 and 1.67 ± 0.745, respectively, and for the tree-lined streets of Pasdaran West and Pasdaran East-Middle, they are 1.43 ± 0.125 and 1.54 ± 0.325, respectively. The results showed that the presence of vegetation and trees in the walls of urban streets, due to their stable environmental reactivity, plays an important role in reducing the thermal crisis and the city's thermal island and preventing changes in thermal comfort status in urban microclimates.

Keywords

Urban green space

trees

urban tree-lined streets

thermal comfort

thermal range

Subjects

Climate change

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