title: Comparative study of potential transfer of natural and anthropogenic cadmium to plankton communities in the North-West African upwelling.
abstract: A Lagrangian approach based on a physical-biogeochemical modeling was used to compare the potential transfer of cadmium (Cd) from natural and anthropogenic sources to plankton communities (Cd-uptake) in the North-West African upwelling. In this region, coastal upwelling was estimated to be the main natural source of Cd while the most significant anthropogenic source for marine ecosystem is provided by phosphate industry. In our model experiment, Cd-uptake (natural or anthropogenic) in the North-West African upwelling is the result of an interplay between the Cd dispersion (by advection processes) and the simulated biological productivity. In the Moroccan waters, advection processes limit the residence time of water masses resulting in a low natural Cd-uptake by plankton communities while anthropogenic Cd-uptake is high. As expected, the situation is reversed in the Senegalo-Mauritanian upwelling where natural Cd-uptake is higher than anthropogenic Cd-uptake. Based upon an estimate of Cd sources, our modeling study shows, unexpectedly, that the anthropogenic signal of potential Cd-bioaccumulation in the Moroccan upwelling is of the same order of magnitude as the natural signal mainly present in the Senegalo-Mauritanian upwelling region. A comparison with observed Cd levels in mollusk and fishes, which shows overall agreement with our simulations, is confirming our estimates.
authors.affiliation: Laboratoire de Physique des Océans (LPO), UMR-CNRS 6523/IFREMER/IRD/UBO, BP70, 29280 Plouzané, France. Electronic address: pierreamael.auger@gmail.com.
authors.forename: P A
authors.initials: PA
authors.lastname: Auger
authors.affiliation: Laboratoire de Physique des Océans (LPO), UMR-CNRS 6523/IFREMER/IRD/UBO, BP70, 29280 Plouzané, France.
authors.forename: E
authors.initials: E
authors.lastname: Machu
authors.affiliation: Laboratoire de Physique des Océans (LPO), UMR-CNRS 6523/IFREMER/IRD/UBO, BP70, 29280 Plouzané, France.
authors.forename: T
authors.initials: T
authors.lastname: Gorgues
authors.affiliation: Laboratoire de Physique des Océans (LPO), UMR-CNRS 6523/IFREMER/IRD/UBO, BP70, 29280 Plouzané, France.
authors.forename: N
authors.initials: N
authors.lastname: Grima
authors.affiliation: Université de Bretagne Occidentale (UBO), Laboratoire de l'Environnement Marin (LEMAR), UMR-CNRS 6539/IRD/UBO, place N. Copernic, 29280 Plouzané, France.
authors.forename: M
authors.initials: M
authors.lastname: Waeles
mesh_terms: D000818:Animals; D002104:Cadmium / Q000032:analysis* / Q000378:metabolism; D017753:Ecosystem; D005399:Fishes / Q000378:metabolism; D020387:Food Chain; D008974:Mollusca / Q000378:metabolism; D010933:Plankton / Q000737:chemistry*; D012623:Seawater / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000378:metabolism
chemical_list: D014874:Water Pollutants, Chemical; D002104:Cadmium
keywords: Bioaccumulation; Cadmium; Dispersion; North-West African upwelling; Phosphate industry; Plankton ecosystem