EGU22-6254
https://doi.org/10.5194/egusphere-egu22-6254
EGU General Assembly 2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

Decoupling the impact of different carbonate system parameters from controlled growth experiments with deep-sea benthic foraminifera

Meryem Mojtahid1, Pauline Depuydt1, Aurélia Mouret1, Fatine Rihani1, Sandrine Le Houedec2, Sarah Fiorini3, Simon Chollet3, Florent Massol3, Francis Dohou3, Helena L. Filipsson4, Wim Boer5, Gert-Jan Reichart5, Sophie Quinchard1, Carole La1, and Christine Barras1
Meryem Mojtahid et al.
  • 1Univ Angers, Univ Nantes, CNRS, LPG, Laboratoire de Planétologie et Géosciences, UMR-CNRS 6112, 2 Bd Lavoisier, 49045 Angers Cedex F-49000 Angers, 2 rue de la Houssinière, BP 92208, France
  • 2Department of Earth Sciences, University of Geneva, Genève, Switzerland
  • 3Ecole Normale Supérieure, CNRS, Centre de Recherche en Écologie Expérimentale et Prédictive (CEREEP-Ecotron Ile-De-France), UMS 3194, PSL Research University, Saint-Pierre-lès-Nemours, France
  • 4Department of Geology, Lund University, Lund, Sweden
  • 5Dept. of Ocean Sciences, Royal Netherlands Institute for Sea Research (NIOZ), Texel, Netherland

Insights into past marine carbon cycling and water mass properties can be obtained with reconstructions of the seawater carbonate system (C-system) through controlled experiments with accurate C-system manipulations. Benthic foraminifera (marine calcifying microorganisms) incorporate various elements into their biogenic calcium carbonate shells as a function of specific environmental parameters. We explore the use of Sr/Ca ratio of the calcite shells as a potential sea water C-system proxy after a controlled growth experiment with two deep-sea foraminiferal species (Bulimina marginata and Cassidulina carinata) and one intertidal species (Ammonia T6). To this aim, we decoupled carbonate chemistry in controlled growth experiments, i.e., changing pH at constant dissolved inorganic carbon (DIC) and changing DIC at constant pH. These experiments were performed for the first time with a new generation of environmental ecological experiment simulators (Ecolab system) allowing a precise control and monitoring of pCO2, temperature and humidity. Four climatic chambers were used with different concentrations of atmospheric pCO2 (180 ppm, 410 ppm, 1000 ppm, 1500 ppm). Preliminary results describe a positive correlation between Sr/Ca and the C-system (DIC/bicarbonate ion concentration) for Ammonia T6 and B. marginata, whereas no correlation with any of the C-system parameters was observed for C. carinata. We hypothesize that Sr/Ca ratios may serve as reliable proxy for the C-system for selected benthic foraminifera species.

How to cite: Mojtahid, M., Depuydt, P., Mouret, A., Rihani, F., Le Houedec, S., Fiorini, S., Chollet, S., Massol, F., Dohou, F., Filipsson, H. L., Boer, W., Reichart, G.-J., Quinchard, S., La, C., and Barras, C.: Decoupling the impact of different carbonate system parameters from controlled growth experiments with deep-sea benthic foraminifera, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-6254, https://doi.org/10.5194/egusphere-egu22-6254, 2022.