title: Enzymatic functional stability of Zn-contaminated field-collected soils: an ecotoxicological perspective.
abstract: Functional stability (FS) is an ecosystem attribute that is increasingly promoted in soil health assessment. However, FS is currently assessed comparatively, and it is therefore impossible to generate toxicity parameters. Additionally, the FS scores in the literature do not consider site and contamination history within the score. To address these issues, three new FS scores adapted to an ecotoxicological context and based on the Relative Soil Stability Index (RSSI) method were developed. The aim of the study was then to determine the FS score(s) that best describe the toxicity of metal-contaminated field-collected soils. Twenty pairs of Zn-contaminated soils (contaminated and reference soils) were collected on the field, and their enzymatic FS (arylsulfatase, protease, phosphatase and urease) and metal fractions (total and bioavailable) were analyzed. New RSSI-based and existing FS scores were calculated for each enzyme and correlated to the Zn fractions. One of the new RSSI-based scores was well correlated with the bioavailable labile Zn concentration for the arylsulfatase, phosphatase and urease (coefficients of regression higher than 0.50). Furthermore, this FS score was not affected by the soil organic matter and depended little on other soil properties. Other FS scores were correlated to labile Zn for only one enzyme, which varied according to the score. The new RSSI-based score thus better attributed Zn toxicity to field-collected soils than other FS scores.
authors.affiliation: CIRAIG, Chemical Engineering Department, Polytechnique Montréal, P.O. Box 6079, Centre-Ville, Montréal, Québec H3C 3A7, Canada. Electronic address: isabelle.lessard@polymtl.ca.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Lessard
authors.affiliation: Department of Chemistry, Université de Montréal, P.O. Box 6128, Centre-Ville, Montréal, QC H3C 3J7, Canada.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Sauvé
authors.affiliation: CIRAIG, Chemical Engineering Department, Polytechnique Montréal, P.O. Box 6079, Centre-Ville, Montréal, Québec H3C 3A7, Canada.
authors.forename: Louise
authors.initials: L
authors.lastname: Deschênes
mesh_terms: D017753:Ecosystem; D054750:Ecotoxicology; D004784:Environmental Monitoring; D012987:Soil / Q000737:chemistry; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000032:analysis / Q000633:toxicity*; D014510:Urease / Q000032:analysis; D015032:Zinc / Q000032:analysis / Q000633:toxicity*
chemical_list: D012987:Soil; D012989:Soil Pollutants; D014510:Urease; D015032:Zinc
keywords: Enzymatic activity; Functional stability; Metal; Multi-stress; Resilience; Tolerance