Assessing the Impact of Urban Green Cover on Air Pollution and Mortality Rates in Tehran

Authors
Kamyab Kiani 1
Mahdi Zandieh 2
Hossein Medi 3
Mohammad Mehdi Zarrabi 4
Maryam Azmoodeh 5
1 PhD Student in Architecture, Faculty of Architecture and Urbanism, Imam Khomeini International University, Qazvin, Iran
2 Professor of Department of Architecture, Faculty of Architecture and Urbanism, Imam Khomeini International University, Qazvin, Iran
3 Associate Professor, Department of Architecture, Faculty of Architecture and Urbanism, Imam Khomeini International University, Qazvin, Iran
4 Associate Professor, Department of Horiculture Engineering, Faculty of Agriculture and Natural Resourses, Imam Khomeini, Qazvin, Iran
5 Assistant Professor, Department of Architecture, Faculty of Architecture and Urbanism, Imam Khomeini International University (IKIU)
10.48311/bsnt.2025.23866
Abstract
Aims: This study aims to investigate and analyze the impact of urban green cover, particularly trees, on reducing air pollution and mortality rates associated with atmospheric pollutants across Tehran's 22 districts.



Methods: The research methodology employed advanced simulations utilizing the i-Tree Canopy tool and air pollution dispersion models. Key pollutants assessed included fine particulate matter (PM2.5), coarse particulate matter (PM10), carbon monoxide, nitrogen dioxide, ozone, and sulfur dioxide. Data on green cover, including per capita green space, area, and number of green spaces, alongside pollutant concentrations and their health impacts, were analyzed across Tehran's districts.



Findings: District 22, with a per capita green space of 62.92 m² and substantial pollutant removal capacities, contributed a 60.80% impact on reducing mortality in Tehran. Districts 1 and 4 also demonstrated favorable performance, with 13.24% and 12.82% impacts, respectively, attributed to their high per capita green spaces. Conversely, districts 7, 8, 9, 10, and 12, with low per capita green spaces, exhibited negligible impacts (below 0.1%), highlighting significant environmental inequities. Green cover effectively reduced PM2.5 and SO2, which are associated with 2.9% and 2.8% increases in respiratory mortality per unit increase in concentration, respectively.



Conclusion: Targeted development of green spaces in underserved districts, especially central and southern areas, coupled with strategies to reduce pollutant emissions from mobile and stationary sources, is essential for urban sustainability and public health. Integrating green technologies, such as green roofs and walls, and continuous air quality monitoring are recommended to address environmental disparities and enhance community well-being.

Keywords

Subjects

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