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Comment
. 2011 Jan 18;108(3):893-4.
doi: 10.1073/pnas.1018163108. Epub 2011 Jan 5.

Loose ligands and available iron in the ocean

Ronald Benner  1
Affiliations
Comment

Loose ligands and available iron in the ocean

Ronald Benner. Proc Natl Acad Sci U S A. .
No abstract available

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Conflict of interest statement

The author declares no conflict of interest.

Figures

Fig. 1.
Fig. 1.
Simplified schematic of iron and saccharide sources, interactions, and utilization in the surface ocean. (A) Aerosol iron rapidly dissolves in the surface ocean and complexes with soluble and colloidal ligands (8), shown as saccharides as described in PNAS by Hassler et al. (3). Saccharides are released from phytoplankton and play an important role in supplying available iron to phytoplankton in a dynamic feedback cycle that enhances biological productivity. Photochemical and biological processes drive the speciation of iron and the production and degradation of colloidal and soluble carbon. Iron is reduced to Fe(II) on the cell surface by phytoplankton before uptake (9). (B) Concentrations of colloidal iron (15) and saccharides (17) in the upper water column of the NPSG. Phytoplankton production maintains high concentrations of colloidal saccharides in surface waters and biological utilization rapidly consumes saccharides in the upper 300 m of the water column. Colloidal iron concentrations follow a similar depth distribution, indicating linkages between the cycling of colloidal iron and organic carbon. (C) Colloidal amino and neutral saccharides, specific components of the total saccharide pool, are also largely produced in the surface ocean and consumed in deeper waters of the NPSG (17, 18). These saccharides show varying dynamics in the upper 200 m, indicating that the cycling of colloidal saccharides varies with composition and is likely to influence the cycling of complexed iron.
See this image and copyright information in PMC

Comment on

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