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In situ measurements of micronutrient dynamics in open seawater show that complex dissociation rates may limit diatom growth.

ABSTRACT: In this first in situ study of the dynamic availability of phytoplankton micronutrients, a SeaExplorer glider was combined with Diffusive Gradients in Thin Films and deployed in the Mediterranean Sea. On the basis of their labile metal complex pools, we discovered that Fe and Co can be potentially limiting and Cu co-limiting to diatom growth, contrary to the generally accepted view that phosphorus (phosphate) is the growth limiting element in the Mediterranean Sea. For flagellates and picoplankton, phosphorus remains the main element limiting growth. Our in situ measurements showed that organic complexes of Fe and Cu (>98% of total dissolved concentration), dissociate slower than inorganic complexes of Co, Cd and Ni (>99% of total dissolved concentration being free ions and inorganic complexes). This strengthens the potential growth limiting effect of Fe and Cu versus phosphate, which is present as a free ion and, thus, directly available for plankton.

SUBMITTER: Baeyens W

PROVIDER: S-EPMC6208410 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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In situ measurements of micronutrient dynamics in open seawater show that complex dissociation rates may limit diatom growth.

Baeyens Willy W Gao Yue Y Davison William W Galceran Josep J Leermakers Martine M Puy Jaume J Superville Pierre-Jean PJ Beguery Laurent L

Scientific reports 20181031 1

In this first in situ study of the dynamic availability of phytoplankton micronutrients, a SeaExplorer glider was combined with Diffusive Gradients in Thin Films and deployed in the Mediterranean Sea. On the basis of their labile metal complex pools, we discovered that Fe and Co can be potentially limiting and Cu co-limiting to diatom growth, contrary to the generally accepted view that phosphorus (phosphate) is the growth limiting element in the Mediterranean Sea. For flagellates and picoplankt ...[more]

PMID: 30382139

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Dataset Information

In situ measurements of micronutrient dynamics in open seawater show that complex dissociation rates may limit diatom growth.

Publications

In situ measurements of micronutrient dynamics in open seawater show that complex dissociation rates may limit diatom growth.

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