The Effectiveness of green belt vegetation in reducing air pollution and noise

Abstract

Introduction: Urbanization, industrial growth, and heavy traffic are driving a rise in air and noise pollution in cities, posing serious threats to public health and environmental sustainability. Airborne particulates can trigger respiratory and cardiovascular conditions, while chronic exposure to high noise levels impairs mental well-being, sleep, and hearing. As a response to these challenges, green belts—vegetated buffer zones—are increasingly recognized for their dual function in mitigating pollution and enhancing urban livability. Methods: This study assessed the environmental performance of three tree species—Moquilea tomentosa Benth, Litsea garciae, and Khaya anthotheca—in reducing air pollutants and noise levels. Data was collected by measuring dust retention per tree and comparing noise intensity between greenbelt and open areas. The pollution capture was analyzed through quantification of particulate deposition, while noise reduction was observed using decibel level comparisons.  Findings: Among the species tested, Khaya anthotheca demonstrated the highest dust-absorbing capability with 501.86 g/tree, followed by Litsea garciae (338.07 g/tree) and Moquilea tomentosa Benth (141.57 g/tree). In terms of acoustic performance, greenbelt areas showed a noise reduction of approximately 16 dB, compared to only 11 dB in non-vegetated spaces. These outcomes highlight the superior pollution-mitigation benefits of certain tree species, particularly when strategically integrated into urban green infrastructure. Conclusion: These findings affirm the vital function of green belts in urban pollution control. The study emphasizes that the strategic selection of tree species and thoughtful planting design can significantly enhance the effectiveness of green infrastructure in improving air quality and reducing environmental noise in city landscapes. Novelty/Originality: The novelty of this study lies in its comparative evaluation of specific tree species for their dual ability to mitigate both air and noise pollution in urban environments—a topic that is often studied separately but rarely in a combined context.