title: Mercury uptake into poplar leaves.
abstract: Tailings dumps require mercury stabilization to prevent air pollution by evaporated mercury, which can be achieved through plant covers. Plants are considered a net sink for atmospheric Hg via incorporation into leaf tissues. However, most studies related to Hg uptake by plants have considered plants exposed to only atmospheric Hg, whereas in the case of tailings dumps, plants are potentially exposed to both soil and atmospheric Hg. The goal of this work is to evaluate the relative contributions of root and atmospheric pathways by growing poplar (Populus trichocarpa X Populus maximowiczii/var Skado) cuttings on either control or polluted substrates and under either natural or controlled exposure conditions. We showed that foliar Hg concentrations significantly increased with age, reaching 120 ng g(-1) dry mass when poplars were exposed to Hg-contaminated substrate under natural exposure. Remarkably, we did not observe significantly different Hg concentrations in poplar leaves grown on either the control or polluted substrates when cultivated together in growth chambers. Our set of data prompted us to conclude that Hg entry into poplar leaves is exclusively through an atmospheric pathway. Our results are discussed in line with existing literature.
authors.affiliation: Laboratoire Chrono-Environnement, UMR CNRS 6249, Université de Bourgogne Franche-Comté, Pôle Universitaire du Pays de Montbéliard, 4 Place Tharradin, BP 71427, 25211 Montbéliard, France.
authors.forename: Mohamad
authors.initials: M
authors.lastname: Assad
authors.affiliation: Laboratoire Chrono-Environnement, UMR CNRS 6249, Université de Bourgogne Franche-Comté, 16 Route de Gray, Besançon Cedex, 25030 France.
authors.forename: Julien
authors.initials: J
authors.lastname: Parelle
authors.affiliation: Solvay Electrolyse France, Tavaux Cedex, 39500 France.
authors.forename: David
authors.initials: D
authors.lastname: Cazaux
authors.affiliation: Laboratoire Chrono-Environnement, UMR CNRS 6249, Université de Bourgogne Franche-Comté, 16 Route de Gray, Besançon Cedex, 25030 France.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Gimbert
authors.affiliation: Laboratoire Chrono-Environnement, UMR CNRS 6249, Université de Bourgogne Franche-Comté, Pôle Universitaire du Pays de Montbéliard, 4 Place Tharradin, BP 71427, 25211 Montbéliard, France; Université de Lorraine, Faculté des Sciences et Technologies, BP 70239, Vandoeuvre-les-Nancy, 54506 France.
authors.forename: Michel
authors.initials: M
authors.lastname: Chalot
authors.affiliation: Laboratoire Chrono-Environnement, UMR CNRS 6249, Université de Bourgogne Franche-Comté, 16 Route de Gray, Besançon Cedex, 25030 France. Electronic address: fabienne.tatin-froux@univ-fcomte.fr.
authors.forename: Fabienne
authors.initials: F
authors.lastname: Tatin-Froux
mesh_terms: D004784:Environmental Monitoring; D005602:France; D008628:Mercury / Q000378:metabolism*; D018515:Plant Leaves / Q000378:metabolism; D018517:Plant Roots / Q000378:metabolism; D032107:Populus / Q000378:metabolism*; D012989:Soil Pollutants / Q000378:metabolism*
chemical_list: D012989:Soil Pollutants; D008628:Mercury
keywords: Field experiment; Leaf Hg concentration; Leaf age; Mercury; Poplar