• Media type: E-Article
  • Title: Fluxes of dissolved aluminum and manganese to the Weddell Sea and indications for manganese co‐limitation
  • Contributor: Middag, Rob; de Baar, Hein J. W.; Klunder, Maarten B.; Laan, Patrick
  • imprint: Wiley, 2013
  • Published in: Limnology and Oceanography
  • Language: English
  • DOI: 10.4319/lo.2013.58.1.0287
  • ISSN: 0024-3590; 1939-5590
  • Keywords: Aquatic Science ; Oceanography
  • Origination:
  • Footnote:
  • Description: <jats:p>The trace metals aluminum (Al) and manganese (Mn) were studied in the Weddell Sea in March 2008. Concentrations of dissolved Al ([Al]) were slightly elevated (0.23–0.35 nmol L<jats:sup>−1</jats:sup>) in the surface layer compared to the subsurface minimum (0.07–0.21 nmol L<jats:sup>−1</jats:sup>) observed in the winter water. Atmospheric deposition is the main source of Al to the central Weddell Sea (22 µmol m<jats:sup>−2</jats:sup> yr<jats:sup>−1</jats:sup>), and the residence time of dissolved Al in the upper mixed layer is ∼ 0.8 yr. The flux from the shelf and slope regions equals about 50% of the atmospheric input of Al to the western Weddell Sea. The highest [Al] in the Weddell Sea bottom water (WSBW) is related to the formation of deep water, and the associated downward flux is in the range of 3–10 µmol Al m<jats:sup>−2</jats:sup> yr<jats:sup>−1</jats:sup>. The concentrations of dissolved Mn ([Mn]) were depleted in the surface layer, likely as a result of biological uptake, as indicated by the correlation among Mn, major nutrients, and fluorescence. The significant negative relation between the ΔMn : ΔP ratio and the ambient concentration of dissolved iron indicates iron‐Mn co‐limitation. The flux of Mn from the continental margin is about 2.2 times greater than atmospheric input (1.1 µmol m<jats:sup>−2</jats:sup> yr<jats:sup>−1</jats:sup>). The flux of both Al and Mn from the continental margin indicates melting of continental ice (icebergs) or direct continental runoff. The slightly elevated [Mn] in the WSBW is due to a relatively small flux of 1 µmol Mn m<jats:sup>−2</jats:sup> yr<jats:sup>−1</jats:sup> associated with WSBW formation.</jats:p>
  • Access State: Open Access