title: On the link between biomagnetic monitoring and leaf-deposited dust load of urban trees: relationships and spatial variability of different particle size fractions.
abstract: Biomagnetic monitoring of urban tree leaves has proven to be a good estimator of ambient particulate matter. We evaluated its relevancy by determining leaf area normalised weight (mg m(-2)) and SIRM (A) of leaf-deposited particles within three different size fractions (>10 μm, 3-10 μm and 0.2-3 μm) and the SIRM of the leaf-encapsulated particles. Results showed that throughout the in-leaf season, the trees accumulated on average 747 mg m(-2) of dust on their leaves, of which 74 mg m(-2) was within the 0.2-10 μm (∼PM10) size range and 40 mg m(-2) within the 0.2-3 μm (∼PM3) size range. A significant correlation between the SIRM and weight of the surface-deposited particles confirms the potential of biomagnetic monitoring as a proxy for the amount of leaf-deposited particles. Spatial variation of both SIRM and weight throughout the street canyon suggests traffic and wind as key factors for respectively the source and distribution of urban particulates.
authors.affiliation: Laboratory of Environmental and Urban Ecology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium. Electronic address: Jelle.Hofman@ua.ac.be.
authors.forename: Jelle
authors.initials: J
authors.lastname: Hofman
authors.affiliation: Laboratory of Environmental and Urban Ecology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium.
authors.forename: Karen
authors.initials: K
authors.lastname: Wuyts
authors.affiliation: Laboratory of Environmental and Urban Ecology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium.
authors.forename: Shari
authors.initials: S
authors.lastname: Van Wittenberghe
authors.affiliation: Laboratory of Environmental and Urban Ecology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium.
authors.forename: Melanka
authors.initials: M
authors.lastname: Brackx
authors.affiliation: Laboratory of Environmental and Urban Ecology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium.
authors.forename: Roeland
authors.initials: R
authors.lastname: Samson
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D004391:Dust / Q000032:analysis*; D004784:Environmental Monitoring / Q000379:methods*; D008280:Magnetics; D010316:Particle Size; D052638:Particulate Matter / Q000032:analysis; D018515:Plant Leaves / Q000737:chemistry*; D012621:Seasons; D014197:Trees / Q000737:chemistry; D014919:Wind
chemical_list: D000393:Air Pollutants; D004391:Dust; D052638:Particulate Matter
keywords: Biomonitoring; PM mass; Particle size; Saturation isothermal remanent magnetisation (SIRM); Urban air pollution