Metal immobilization and soil amendment efficiency at a contaminated sediment landfill site: a field study focusing on plants, springtails, and bacteria

Valérie Bert (1, 2) , Christine Lors (1, 3, 4) , Jean-François Ponge (5) , Lucie Caron (2) , Asmaa Biaz (5) , Marc Dazy (6) , Jean-François Masfaraud (6)

1 CNRSSP - Centre National de Recherche sur les Sites et Sols Pollués
2 INERIS - Institut National de l'Environnement Industriel et des Risques
3 CERI MP - IMT Nord Europe - Centre for Materials and Processes
4 LGCgE - Laboratoire de Génie Civil et Géo-Environnement (LGCgE) - ULR 4515
5 MAOAC - Mécanismes adaptatifs : des organismes aux communautés
6 LIEBE - Laboratoire des Interactions Ecotoxicologie, Biodiversité, Ecosystèmes

Metal immobilization may contribute to the environmental management strategy of dredged sediment landfill sites contaminated by metals. In a field experiment, amendment effects and efficiency were investigated, focusing on plants, springtails and bacteria colonisation, metal extractability and sediment ecotoxicity. Conversely to hydroxylapatite (HA, 3% DW), the addition of Thomas Basic Slag (TBS, 5% DW) to a 5-yr deposited sediment contaminated with Zn, Cd, Cu, Pb and As resulted in a decrease in the 0.01 M Ca(NO(3))(2)-extractable concentrations of Cd and Zn. Shoot Cd and Zn concentration in Calamagrostis epigejos, the dominant plant species, also decreased in the presence of TBS. The addition of TBS and HA reduced sediment ecotoxicity and improved the growth of the total bacterial population. Hydroxylapatite improved plant species richness and diversity and decreased antioxidant enzymes in C. Epigejos and Urtica dïoica. Collembolan communities did not differ in abundance and diversity between the different treatments.

Mots clés: basic slag; Calamagrostis epigejos; dredged sediment; hydroxylapatite; ecotoxicity

Domaines: Science des sols

Valérie Bert, Christine Lors, Jean-François Ponge, Lucie Caron, Asmaa Biaz, et al.. Metal immobilization and soil amendment efficiency at a contaminated sediment landfill site: a field study focusing on plants, springtails, and bacteria. Environmental Pollution, 2012, 169, pp.1-11. ⟨10.1016/j.envpol.2012.04.021⟩. ⟨hal-00704382⟩