title: Evergreen or deciduous trees for capturing PAHs from ambient air? A case study.
abstract: Tree canopies play a key role in the cycling of polycyclic aromatic hydrocarbons (PAHs) in terrestrial ecosystems, as leaves can capture PAHs from the air. In this study, accumulation of PAHs was compared in an evergreen species, P. pinaster, and in a deciduous species, Q. robur, in relation to some physio-morphological characteristics. For this purpose, pine needles and oak leaves collected from different sites across Galicia (NW Spain) were analysed to determine PAH contents, specific leaf area, stomatal density and conductance. Leaves and needles contained similar total amounts of PAHs. The major contribution of particle-bound PAHs in oak (the concentrations of 4- and 5-ring PAHs were two times higher, and those of 6-ring PAHs five times higher in oak than in pine) may be related to the higher specific leaf area (13 and 4 cm2g-1dry mass in respectively oak and pine). However, the major contribution of vapor-phase PAHs in pines may be affected by the stomatal conductance (two times higher in pine than in oak). Moreover, an increase in the diameter at breast height of trees led to an increase in accumulation of PAHs, with pine capturing higher amounts of low and medium molecular weight PAHs. The study findings underline the potential role of trees in improving air quality, taking into account the canopy biomass and life cycle.
authors.affiliation: Dipartimento Scienze e Tecnologie, Università degli Studi del Sannio, Via Port'Arsa 11, 82100 Benevento, Italy. Electronic address: fdenicol@unisannio.it.
authors.forename: Flavia
authors.initials: F
authors.lastname: De Nicola
authors.affiliation: Grupo Química Analítica Aplicada (QANAP), Instituto Universitario de Medio Ambiente (IUMA), Centro de Investigaciones Científicas Avanzadas (CICA), Departamento Química Analítica, Facultad de Ciencias, Universidade da Coruña, 15071 A Coruña, Spain.
authors.forename: Estefanía
authors.initials: E
authors.lastname: Concha Graña
authors.affiliation: Grupo Química Analítica Aplicada (QANAP), Instituto Universitario de Medio Ambiente (IUMA), Centro de Investigaciones Científicas Avanzadas (CICA), Departamento Química Analítica, Facultad de Ciencias, Universidade da Coruña, 15071 A Coruña, Spain.
authors.forename: Purificación
authors.initials: P
authors.lastname: López Mahía
authors.affiliation: Grupo Química Analítica Aplicada (QANAP), Instituto Universitario de Medio Ambiente (IUMA), Centro de Investigaciones Científicas Avanzadas (CICA), Departamento Química Analítica, Facultad de Ciencias, Universidade da Coruña, 15071 A Coruña, Spain.
authors.forename: Soledad
authors.initials: S
authors.lastname: Muniategui Lorenzo
authors.affiliation: Grupo Química Analítica Aplicada (QANAP), Instituto Universitario de Medio Ambiente (IUMA), Centro de Investigaciones Científicas Avanzadas (CICA), Departamento Química Analítica, Facultad de Ciencias, Universidade da Coruña, 15071 A Coruña, Spain.
authors.forename: Darío
authors.initials: D
authors.lastname: Prada Rodríguez
authors.affiliation: Área de Ecología, Departamento de Biología Funcional, Facultad de Biología, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain.
authors.forename: Rubén
authors.initials: R
authors.lastname: Retuerto
authors.affiliation: Área de Ecología, Departamento de Biología Funcional, Facultad de Biología, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain.
authors.forename: Alejo
authors.initials: A
authors.lastname: Carballeira
authors.affiliation: Área de Ecología, Departamento de Biología Funcional, Facultad de Biología, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain.
authors.forename: Jesús R
authors.initials: JR
authors.lastname: Aboal
authors.affiliation: Área de Ecología, Departamento de Biología Funcional, Facultad de Biología, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain.
authors.forename: J Ángel
authors.initials: JÁ
authors.lastname: Fernández
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D018533:Biomass; D017753:Ecosystem; D004784:Environmental Monitoring / Q000379:methods*; D005740:Gases / Q000032:analysis; D028223:Pinus; D018515:Plant Leaves / Q000737:chemistry; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis*; D013030:Spain; D014197:Trees / Q000737:chemistry / Q000502:physiology*
chemical_list: D000393:Air Pollutants; D005740:Gases; D011084:Polycyclic Aromatic Hydrocarbons
keywords: Leaf morphology; PAH accumulation; Specific leaf area; Stomata