www.elsevier.nlrlocatermarchem Zinc speciation in the Northeastern Atlantic Ocean

Measurements of zinc and zinc complexation by natural organic ligands in the northeastern part of the Atlantic Ocean were made using cathodic stripping voltammetry with ligand competition. Total zinc concentrations ranged from 0.3 nM in surface waters to 2 nM at 2000 m for open-ocean waters, whilst...

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Bibliographic Details
Main Authors: Michael J. Ellwood, Constant M. G, Van Berg
Other Authors: The Pennsylvania State University CiteSeerX Archives
Format: Text
Language:English
Published: 1999
Subjects:
Online Access:http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.517.7736
http://www.liv.ac.uk/~sn35/Documents/Papers/Ellwood %26 vandenBerg MC 2000.pdf
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Summary:Measurements of zinc and zinc complexation by natural organic ligands in the northeastern part of the Atlantic Ocean were made using cathodic stripping voltammetry with ligand competition. Total zinc concentrations ranged from 0.3 nM in surface waters to 2 nM at 2000 m for open-ocean waters, whilst nearer the English coast, zinc concentrations reached 1.5 nM in the upper water column. In open-ocean waters zinc speciation was dominated by complexation to a natural organic X.ligand with conditional stability constant log K ranging between 10.0 and 10.5 and with ligand concentrations rangingZnL between 0.4 and 2.5 nM. The ligand was found to be uniformly distributed throughout the water column even though zinc concentrations increased with depth. Organic ligand concentrations measured in this study are similar to those published for the North Pacific. However the log K X values for the North Atlantic are almost and order of magnitude lower than thoseZnL wreported by Bruland Bruland, K.W., 1989. Complexation of zinc by natural organic-ligands in the central North Pacific. xLimnol. Oceanogr., 34, 269–285. using anodic stripping voltammetry for the North Pacific. Free zinc ion concentrations .were low in open-ocean waters 6–20 pM but are not low enough to limit growth of a typical oceanic species of