TY - JOUR TI - The biogeochemistry of cobalt in the Mediterranean Sea AU - Dulaquais, Gabriel AU - Planquette, Hélène AU - L'Helguen, Stephane AU - Rijkenberg, Micha J. A. AU - Boye, Marie T2 - Global Biogeochemical Cycles AB - The soluble (sCo < 0.02 mu m), dissolved (DCo < 0.2 mu m), colloidal (cCo, as DCo minus sCo), and the particulate ( pCo > 0.2 mu m) fractions of cobalt were investigated along the GEOTRACES-A04 section. Our results show that sCo was the predominant form (90%) of the DCo in the Mediterranean Sea and that cCo and pCo generally followed the same distribution, suggesting a biogeochemical link between these two fractions. In the Mediterranean Sea, DCo displayed an overall scavenged-like profile in the different sub- basins, with high concentrations (up to 350 pM) in surface and quasi-uniformed low concentrations of DCo (similar to 45 pM) in the deep sea. However, the decoupling between the surface and the deep reservoirs suggested that the transfer of Co from dissolved to particulate pools during the sink of particles may not be the only process governing DCo distribution. High-surface Co inputs, stabilization of DCo in a soluble form, and the extremely high regeneration rate of biogenic pCo all lead to the accumulation of DCo in surface. Conversely, low pCo export from the surface waters, low remineralization of biogenic pCo, and slow but efficient removal of DCo by scavenging including colloid aggregation into particles prevented its accumulation in the intermediate and deep sea. Moreover, Mediterranean circulation prevented the exchanges between the DCo-rich surface and the DCo-poor deep layers enhancing the scavenged-like profile of DCo. Finally, tentative DCo budgets were balanced at basin scale and showed the strong imprint of the surface inputs at Gibraltar Strait on the Mediterranean cobalt biogeochemistry. DA - 2017/02// PY - 2017 DO - 10.1002/2016GB0054780 DP - Web of Science VL - 31 IS - 2 SP - 377 EP - 399 J2 - Glob. Biogeochem. Cycle LA - English SN - 0886-6236 KW - ACL KW - BITMAP_ANR-12-PDOC-0025 KW - CNRS KW - UBO KW - carbon export KW - cathodic stripping voltammetry KW - chibido KW - dissolved cobalt KW - elemental composition KW - marine diatom KW - north-atlantic KW - particulate metals KW - phosphorus limitation KW - trace-metal composition KW - western atlantic-ocean ER -