title: Soil trace element changes during a phytoremediation trial with willows in southern Québec, Canada.
abstract: This study determined the changes in trace elements (TE) (As, Cd, Cu, Ni, Pb, Zn) chemistry in the soils of a willow ("Fish Creek" - Salix purpurea, SV1 - Salix x dasyclados and SX67 - Salix miyabeana) plantation growing under a cold climate during a three-year trial. The soil HNO3-extractable and H2O-soluble TE concentrations and pools significantly decreased under most cultivars (Fish, SX67). Yet, TE changes showed inconsistent patterns and localized soil TE increases (Ni, Pb) were measured. Temporal changes in soil TE were also detected in control plots and sometimes exceeded changes in planted plots. Discrepancies existed between the amount of soil TE change and the amount of TE uptake by willows, except for Cd and Zn. Phytoremediation with willows could reduce soil Cd and Zn within a decadal timeframe indicating that they can be remediated by willows in moderately contaminated soils. However, the time needed to reduce soil As, Cu, Ni and Pb was too long to be efficient. We submit that soil leaching contributed to the TE decrease in controls and the TE discrepancies, and that the plantation could have secondary effects such as the accelerated leaching of soil TE.
authors.affiliation: a Département de Géographie , Université de Montréal , Montréal , QC , Canada.
authors.forename: François
authors.initials: F
authors.lastname: Courchesne
authors.affiliation: a Département de Géographie , Université de Montréal , Montréal , QC , Canada.
authors.forename: Marie-Claude
authors.initials: MC
authors.lastname: Turmel
authors.affiliation: a Département de Géographie , Université de Montréal , Montréal , QC , Canada.
authors.forename: Benoît
authors.initials: B
authors.lastname: Cloutier-Hurteau
authors.affiliation: a Département de Géographie , Université de Montréal , Montréal , QC , Canada.
authors.forename: Gilbert
authors.initials: G
authors.lastname: Tremblay
authors.affiliation: a Département de Géographie , Université de Montréal , Montréal , QC , Canada.
authors.forename: Lara
authors.initials: L
authors.lastname: Munro
authors.affiliation: b Institut de Recherche en Biologie Végétale, Université de Montréal and Jardin Botanique de Montréal , Montréal , QC , Canada.
authors.forename: Jacynthe
authors.initials: J
authors.lastname: Masse
authors.affiliation: b Institut de Recherche en Biologie Végétale, Université de Montréal and Jardin Botanique de Montréal , Montréal , QC , Canada.
authors.forename: Michel
authors.initials: M
authors.lastname: Labrecque
mesh_terms: D001673:Biodegradation, Environmental; D002170:Canada; D011792:Quebec; D032108:Salix; D012987:Soil; D012989:Soil Pollutants; D014131:Trace Elements
chemical_list: D012987:Soil; D012989:Soil Pollutants; D014131:Trace Elements
keywords: field trial; phytoremediation; soil leaching; trace elements; willows