Insights into the bioavailability of oceanic dissolved Fe from phytoplankton uptake kinetics.

ABSTRACT: Phytoplankton growth in large parts of the world ocean is limited by low availability of dissolved iron (dFe), restricting oceanic uptake of atmospheric CO₂. The bioavailability of dFe in seawater is however difficult to appraise since it is bound by a variety of poorly characterized organic ligands. Here, we propose a new approach for evaluating seawater dFe bioavailability based on its uptake rate constant by Fe-limited cultured phytoplankton. We utilized seven phytoplankton species of diverse classes, sizes, and provenances to probe for dFe bioavailability in 12 seawater samples from several ocean basins and depths. All tested phytoplankton acquired organically bound Fe in any given sample at similar rates (after normalizing to cellular surface area), confirming that multiple

SUBMITTER: Shaked Y 

PROVIDER: S-EPMC7174416 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature