Heme b distributions through the Atlantic Ocean: evidence for “anemic” phytoplankton populations.

Louropoulou, Evangelia , Gledhill, Martha , Achterberg, Eric P. , Browning, Thomas J. , Honey, David J., Schmitz, Ruth A. and Tagliabue, Alessandro (2020) Heme b distributions through the Atlantic Ocean: evidence for “anemic” phytoplankton populations. Open Access Scientific Reports, 10 (Article number: 4551). DOI 10.1038/s41598-020-61425-0.

[img]
Preview
Text
s41598-020-61425-0.pdf - Published Version
Available under License Creative Commons: Attribution 4.0.

Download (8Mb) | Preview
[img]
Preview
Text
41598_2020_61425_MOESM1_ESM.pdf - Supplemental Material
Available under License Creative Commons: Attribution 4.0.

Download (463Kb) | Preview

Supplementary data:

Abstract

Heme b is an iron-containing cofactor in hemoproteins that participates in the fundamental processes of photosynthesis and respiration in phytoplankton. Heme b concentrations typically decline in waters with low iron concentrations but due to lack of field data, the distribution of heme b in particulate material in the ocean is poorly constrained. Here we report particulate heme b distributions across the Atlantic Ocean (59.9°N to 34.6°S). Heme b concentrations in surface waters ranged from 0.10 to 33.7 pmol L−1 (median = 1.47 pmol L−1, n = 974) and were highest in regions with a high biomass. The ratio of heme b to particulate organic carbon (POC) exhibited a mean value of 0.44 μmol heme b mol−1 POC. We identified the ratio of 0.10 µmol heme b mol−1 POC as the cut-off between heme b replete and heme b deficient (anemic) phytoplankton. By this definition, we observed anemic phytoplankton populations in the Subtropical South Atlantic and Irminger Basin. Comparison of observed and modelled heme b suggested that heme b could account for between 0.17–9.1% of biogenic iron. Our large scale observations of heme b relative to organic matter provide further evidence of the impact of changes in iron supply on phytoplankton iron status across the Atlantic Ocean.

Document Type: Article
Additional Information: Data availability Heme b and supporting data are available on the British Oceanographic Data Centre, http://www.bodc.ac.uk/.
Keywords: Heme b, phytoplankton, Atlantic Ocean, iron limitation, biogenic iron
Research affiliation: OceanRep > GEOMAR > FB2 Marine Biogeochemistry > FB2-CH Chemical Oceanography
Kiel University
Refereed: Yes
Open Access Journal?: Yes
DOI etc.: 10.1038/s41598-020-61425-0
ISSN: 2045-2322
Projects: HOSST, GEOVIDE
Expeditions/Models/Experiments:
Date Deposited: 16 Mar 2020 13:36
Last Modified: 18 Jun 2020 08:16
URI: http://oceanrep.geomar.de/id/eprint/49266

Actions (login required)

View Item View Item

Document Downloads

More statistics for this item...