University of Tasmania
Browse

File(s) under permanent embargo

Dissolution of coccolithophorid calcite by microzooplankton and copepod grazing

journal contribution
posted on 2023-05-17, 07:29 authored by Antia, AN, Suffrian, K, Holste, L, Muller, MN, Nejstgaard, JC, Simonelli, P, Carotenuto, Y, Putzeys, S
Independent of the ongoing acidification of surface seawater, the majority of the calcium carbonate produced in the pelagial is dissolved by natural processes above the lysocline. We investigate to what extent grazing and passage of coccolithophorids 5 through the guts of copepods and the food vacuoles of microzooplankton contribute to calcite dissolution. In laboratory experiments where the coccolithophorid Emiliania huxleyi was fed to the rotifer Brachionus plicatilis, the heterotrophic flagellate Oxyrrhis marina and the copepod Acartia tonsa, calcite dissolution rates of 45–55%, 37–53% and 5–22% of ingested calcite were found. We ascribe higher loss rates in microzoo10 plankton food vacuoles as compared to copepod guts to the strongly acidic digestion and the individual packaging of algal cells. In further experiments, specific rates of calcification and calcite dissolution were also measured in natural populations during the PeECE III mesocosm study under differing ambient pCO2 concentrations. Microzooplankton grazing accounted for between 27 and 70% of the dynamic calcite stock 15 being lost per day, with no measurable effect of CO2 treatment. These measured calcite dissolution rates indicate that dissolution of calcite in the guts of microzooplankton and copepods can account for the calcite losses calculated for the global ocean using budget and model estimates.

History

Publication title

Biogeosciences Discussions

Volume

5

Pagination

1-23

ISSN

1810-6277

Department/School

Institute for Marine and Antarctic Studies

Publisher

Copernicus GmbH

Place of publication

Germany

Rights statement

Copyright © Author(s) 2008. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Repository Status

  • Restricted

Socio-economic Objectives

Expanding knowledge in the biological sciences

Usage metrics

    University Of Tasmania

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC