The Impact of Urban Green Spaces and Built Environments on Air Quality in Kampala City: A Comparative Analysis

Purpose: The study analyzed the multifaceted dynamics between green vegetated areas and built environments on air quality within Kampala City. Six (6) streets were sampled: - Nasser Lane, 6th Street, Namirembe Road, Owino Kafumbe- Mukasa, Makindu Close, and Nakasero Lane. Makindu Close and Nakasero Lane are known for green vegetation, 6th Street is known for buildings and industrial zones, while Namirembe Road and Owino Kafumbe- Mukasa are known for car parks. Methodology: The survey used cross-sectional studies and quantitative approaches during data collection and analysis. The air quality parameters sampled included Particulate Matter (PM2.5 and PM10), Nitrogen dioxide (NO2), Sulfur dioxide (SO2), and Carbon monoxide (CO) from various points within the city center. Findings: Results showed that the 6th Street industrial area was the most polluted area of the city, with PM2.5, PM10, and NO2 exceeding the World Health Organization’s (WHO) recommended 2021 Air Quality Guidelines (AQG) levels by 100%, 86.96% and 100%, respectively. Namirembe Road and Owino Kafumbe- Mukasa were also polluted with Carbon monoxide, Sulphur dioxide and Nitrogen dioxide. However, Owino Kafumbe-Mukasa’s Carbon monoxide levels exceeded WHO’s recommended Air Quality Guidelines (AQG) levels by 95.65%. Nkrumah-Nasser Lane and Nakasero Lane had mostly non-significant or less significant effects on pollutant levels. Makindu Close was less polluted; results indicated better air quality, especially with NO2. Unique Contribution to Theory, Policy and Practice: Increasing green vegetation within the city is thus recommended to improve air purity, as evidenced in the Makindu Close and Nakasero Lane analysis. This research demonstrates a clear inverse relationship between green cover and pollutant levels, offering empirical evidence to support the promotion of urban greening initiatives as a practical solution to air quality challenges in rapidly developing cities like Kampala.