J. Phys. IV France 107 (2003) 41
DOI: 10.1051/jp4:20030238

Transfer of metallic contaminants at the sediment-water interface in a costal lagon : Role of the biological and microbial activity

D. Amouroux¹, M. Monperrus¹, D. Point¹, E. Tessier¹, G. Bareille¹, O.F.X. Donard¹, L. Chauvaud¹, G. Thouzeaul¹, F. Jean², J. Grall², A. Leynaert², J. Clavier², R. Guyonneaud³, R. Duran³, M.S. Goni³ and P. Caumette<sup>3

1</sup>  Laboratoire de Chimie Analytique Bio-Inorganique et Environnement, UMR 5034 du CNRS, Université de Pau et des Pays de l'Adour, Hélioparc, 64053 Pau, France
²  Laboratoire des Sciences de l'Environnement Marin (LEMAR), IUEM, UMR 6539 du CNRS-UBO, Brest, France
³  Laboratoire d'Ecologie Moléculaire (LEM), Université de Pau et des Pays de l'Adour, Pau, France

Abstract
Sediment-water exchanges of trace metals and organometals in coastal environments are of primary concern fur their cycling and environmental impact in these ecosystems. A multidisciplinary approach has been camed out in the Thau Lagoon on the French Mediterranean coast in order to investigate the role of the benthic ecology on trace metals and organometals cycling at the sediment water-interface (Hg, Cd, Pb, Cu, Ni, MeHg ⁺, Bu ₃Sn ⁺). Incubation experiments have been performed at the sediment water-interface at different stations using benthic chambers. Both hydrological parameters and trace metals and organometals have been sampled during these incubations in order to obtain an estimation of the sediment-water exchange fluxes. Benthic macrofauna and microbial populations have been examined to determined the major biological processes driving the benthic ecology at the different stations. The results indicate that the heterotrophic versus autotrophic benthic characteristics, as well as macrobenthic population, are driving factors for the sediment-water exchanges of trace metals and organometals.

© EDP Sciences 2003