Dissolved trace metals (Ni, Zn, Co, Cd, Pb, Al, and Mn) around the Crozet Islands, Southern Ocean

• Published in: Journal of Geophysical Research: Oceans
• Main Authors: Castrillejo, Maxi, Statham, Peter J., Fones, Gary R., Planquette, Hélène, Idrus, Farah, Roberts, Keiron
• Other Authors: National Oceanography Centre Southampton (NOC), University of Southampton, Institut de Ciencia i Tecnologia Ambientals (ICTA), Universitat Autònoma de Barcelona (UAB), School of Earth and Environment Sciences, University of Portsmouth, Laboratoire des Sciences de l'Environnement Marin (LEMAR) (LEMAR), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Institut Universitaire Européen de la Mer (IUEM), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Faculty of Resources Science and Technology, University Malaysia
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2013
• Subjects: Southern Ocean; trace metals; biogeochemical cycles; iron fertilization; [SDU.STU.MI]Sciences of the Universe [physics]/Earth Sciences/Mineralogy; [SDE]Environmental Sciences; Austral; Crozet Islands
• Online Access: https://hal.univ-brest.fr/hal-00939263; https://hal.univ-brest.fr/hal-00939263/document; https://hal.univ-brest.fr/hal-00939263/file/jJGR-Castrillejo.pdf; https://doi.org/10.1002/JGRC.20359

International audience A phytoplankton bloom shown to be naturally iron (Fe) induced occurs north of the Crozet Islands (Southern Ocean) every year, providing an ideal opportunity to study dissolved trace metal distributions within an island system located in a high nutrient low chlorophyll (HNLC) region. We present water column profiles of dissolved nickel (Ni), zinc (Zn), cobalt (Co), cadmium (Cd), lead (Pb), aluminium (Al), and manganese (Mn) obtained as part of the NERC CROZEX program during austral summer (2004-2005). Two stations (M3 and M1) were sampled downstream (north) of Crozet in the bloom area and near the islands, along with a control station (M2) in the HNLC zone upstream (south) of the islands. The general range found was for Ni, 4.64-6.31 nM; Zn, 1.59-7.75 nM; Co, 24-49 pM; Cd, 135-673 pM; Pb, 6-22 pM; Al, 0.13-2.15 nM; and Mn, 0.07-0.64 nM. Vertical profiles indicate little island influence to the south with values in the range of other trace metal deprived regions of the Southern Ocean. Significant removal of Ni and Cd was observed in the bloom and Zn was moderately correlated with reactive silicate (Si) indicating diatom control over the internal cycling of this metal. Higher concentrations of Zn and Cd were observed near the islands. Pb, Al, and Mn distributions also suggest small but significant atmospheric dust supply particularly in the northern region.