Giráldez Suárez, PabloVarela Río, ZulemaDi Guardo, AntonioTerzaghi, ElisaCeleiro Montero, MaríaGarcía Jares, Carmen MaríaFernández Escribano, José ÁngelAboal Viñas, Jesús2024-09-272024-09-272024Science of The Total Environment Volume 940 , 25 August 2024, 1736980048-9697http://hdl.handle.net/10347/34930The emission of potentially harmful compounds, including polycyclic aromatic hydrocarbons (PAHs), and the resulting air pollution is a serious problem in modern cities. It is therefore important to develop mitigation strategies, such as “smart” planting of trees that act as sinks for PAHs. However, the intra-individual (within-tree) variability in leaf PAH concentrations remains unknown. In this paper, we studied 15 ornamental apple trees (Malus × moerlandsii ‘Profusion’) growing on a main street in a medium-sized city in Galicia (NW Spain). We determined the PAH concentrations at 12 canopy positions in each tree (2 orientations and 2 distances from the trunk at 3 heights), measured various ecological traits (specific leaf area [SLA], δ13C, stomatal density, fatty acid contents and leaf hairiness) and analyzed the variability in traits within the canopy in relation to PAH concentrations. We observed high intra-individual variability in the PAH concentrations and the leaf traits. Statistical analyses revealed that leaf height was the main source of variability both in the PAH concentrations and in the traits, mainly due to the leaf morphology, particularly to the SLA. Therefore, the ideal vegetation to remove PAHs would be high leaf biomass trees, not too tall and with a high proportion of shade leaves.engAtribución-NoComercial 4.0 Internacional© 2024 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC licensehttp://creativecommons.org/licenses/by-nc/4.0/LeavesC isotopesAtmospheric pollutionUrban treeTrafficjournal article10.1016/j.scitotenv.2024.173698open access