Advances on the Influence of Vegetation and Forest on Urban Air Quality and Thermal Comfort

Urbanisation has intensified environmental challenges, particularly through the deterioration of air quality and the amplification of heat stress, both of which directly affect public health and urban liveability. Vegetation- and forest-based strategies, often framed as nature-based solutions (NBSs), have consequently gained relevance as key tools to mitigate these problems by reducing air pollutant concentrations, improving thermal comfort, and delivering a wide range of co-benefits. Their influence, however, is neither uniform nor linear, since aerodynamic, deposition, shading, and evapotranspiration processes interact in complex ways with urban morphology, atmospheric pollutants, and meteorological conditions. As a result, understanding the role of vegetation in shaping urban environments requires interdisciplinary approaches and evidence from both experimental and modelling studies. In the present Reprint, we offer new insights into the multiple mechanisms through which vegetation affects air quality, the microclimate, and thermal comfort, while also highlighting the challenges of designing context-sensitive green infrastructures that carefully account for the specific environmental, urban, and social conditions in which they are embedded.