Exploring the Impact of Urban Vegetation on Particulate Matter Levels and Urban Environment Enhancement

Abstract

Atmospheric pollution is considered the world’s most serious environmental health hazard by the World Health Organization (WHO). A polluted environment was estimated to be responsible for over 6 million causalities worldwide in 2016, twice as many as AIDS, tuberculosis, and malaria combined. Particulate matter (PM) is one of the major atmospheric pollutants from various sources; however, it mainly consists of suspended roadside dust particles. The size of PM depends on its sources and also on elemental composition. To reduce disease incidents worldwide, it becomes necessary to lower the levels of atmospheric pollutants. Great efforts are being made to evaluate and reduce atmospheric pollutants in urban areas. Since the late 19^th century, many researchers have been ambitious to understand the nature of atmospheric pollutants and to invent tools and techniques for their mitigation. Urban vegetation acts as a good bio-monitor technique because of its capacity to intercept dust particles and absorb or retain them over time. Urban vegetation also efficiently reduces gaseous air pollutants primarily by their uptake via leaf stomata. This paper discusses the quality of air in urban areas and the significance of urban trees in reducing air pollutants, particularly particulate matter, around the globe. The mineralogical and elemental profiling of urban dust particles concerning their distribution and size have been thoroughly reviewed. Furthermore, the two-way interactions of PM with urban trees in terms of the capacity of urban vegetation to intercept PM and changes in vegetation’s physiology in reaction to PM load have been described.