Particulate matter concentrations and fluxes within an urban park in Naples

Airborne particulate matter can represent a serious issue for human health, especially in densely populated urban areas. Moreover, the inhalation of particulate can be more harmful with decreasing particles diameter. Vegetation can provide many ecosystem services to the citizens, including the removal of many different pollutants in the air, but while the effect on many gaseous compounds has already been widely proved, the capability of particulate matter (PM) sequestration driven by vegetation and its resulting benefit on air quality has not been deeply investigated yet at larger spatial scale, especially in Mediterranean environment. This study was conducted in the Real Bosco di Capodimonte, a green area of about 125 ha located inside the urban area of Naples (Italy) containing different species typical of the Mediterranean forest ecosystem. To better understand the interaction between PM and the park area, we measured fluxes of PM₁₀, PM_2.5 and PM₁ with a fast acquisition analyser, according to the Eddy Covariance technique. We found that the particle deposition was higher during the central hours of the day and it was more evident for smaller size particles. Furthermore, the daily PM fluxes found accorded with evapotranspiration and carbon sequestration operated by plants, suggesting a possible active role of vegetation on the particulate deposition.