A multi-proxy magnetic approach for monitoring large-scale airborne pollution impact

Ynse Declercq; Roeland Samson; Ellen Van De Vijver; Johan De Grave; Filip M G Tack; Philippe De Smedt

doi:10.1016/j.scitotenv.2020.140718

A multi-proxy magnetic approach for monitoring large-scale airborne pollution impact

Sci Total Environ. 2020 Nov 15:743:140718. doi: 10.1016/j.scitotenv.2020.140718. Epub 2020 Jul 10.

Authors

Ynse Declercq¹, Roeland Samson², Ellen Van De Vijver³, Johan De Grave⁴, Filip M G Tack⁵, Philippe De Smedt⁶

Affiliations

¹ Research Group Soil Spatial Inventory Techniques, Department of Environment, Ghent University, Coupure Links 653, 9000 Ghent, Belgium; Laboratory of Environmental and Urban Ecology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium. Electronic address: Ynse.Declercq@UGent.be.
² Laboratory of Environmental and Urban Ecology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium.
³ Research Group Soil Spatial Inventory Techniques, Department of Environment, Ghent University, Coupure Links 653, 9000 Ghent, Belgium.
⁴ Mineralogy and Petrology Research Unit, Department of Geology, Ghent University, Krijgslaan 281/S8, 9000 Ghent, Belgium.
⁵ Laboratory of Analytical Chemistry and Applied Ecochemistry, Department of Green Chemistry and Technology, Ghent University, Coupure Links 653, 9000 Ghent, Belgium.
⁶ Research Group Soil Spatial Inventory Techniques, Department of Environment, Ghent University, Coupure Links 653, 9000 Ghent, Belgium. Electronic address: Philippe.DeSmedt@UGent.be.

PMID: 32758833
DOI: 10.1016/j.scitotenv.2020.140718

Abstract

The interpretive utility of environmental magnetic proxies for investigating airborne particulate matter (PM) pollution impact is restricted by differences in soil composition, land cover and land use. For soil magnetic applications, land use strongly influences magnetic particle distribution down the soil profile, even in homogeneous soil environments. Here, an adaptive approach is engineered to provide accurate magnetic proxy information for pollution monitoring across different land use types. In an 81-km² area between two industrial harbours, the irregular distribution of forests, arable lands, pasture and residential areas prevented robustly relating topsoil magnetic susceptibility data to known pollution impacts. Although normalized topsoil susceptibility values showed improved potential for deriving airborne pollution impacts, optimal results were obtained by depth-integrating magnetic susceptibility logs, revealing long-term impacts of both active and decommissioned industrial facilities. Complementing soil magnetic observations, active and passive (bio)magnetic monitoring allowed discriminating short-term pollution patterns and evaluating changes in PM impact across the study area. Hereby, active PM receptors (strawberry leaves and plastic coated cardboards (PCCs)) provided promising results, yet passive receptors allowed estimating pollution impacts more efficiently. For the latter, species-independent grass leaf sampling reflected airborne PM depositional patterns most accurately, whereas wiped anthropogenic surfaces proved too sensitive to wash-off.

Keywords: (bio)magnetic monitoring; Environmental magnetism; Magnetic susceptibility; PM pollution; SIRM; Soil.