Articles | Volume 22, issue 7
https://doi.org/10.5194/bg-22-1887-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-22-1887-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
17 Apr 2025
Research article |
| 17 Apr 2025
| 17 Apr 2025
Effects of photosymbiosis and related processes on planktic foraminifera-bound nitrogen isotopes in South Atlantic sediments
Alexandra Auderset
CORRESPONDING AUTHOR
School of Ocean and Earth Science, University of Southampton, Southampton, SO14 3ZH, UK
Climate Geochemistry Department, Max Planck Institute for Chemistry Mainz, 55128 Mainz, Germany
Sandi M. Smart
Department of Geological Sciences, University of Alabama, Tuscaloosa, AL 35401, USA
Yeongjun Ryu
Department of Geosciences, Princeton University, Princeton, NJ 08544, USA
Dario Marconi
Department of Geosciences, Princeton University, Princeton, NJ 08544, USA
Haojia Abby Ren
Department of Geosciences, National Taiwan University, Taipei, 106, Taiwan
Lena Heins
Climate Geochemistry Department, Max Planck Institute for Chemistry Mainz, 55128 Mainz, Germany
Hubert Vonhof
Climate Geochemistry Department, Max Planck Institute for Chemistry Mainz, 55128 Mainz, Germany
Ralf Schiebel
Climate Geochemistry Department, Max Planck Institute for Chemistry Mainz, 55128 Mainz, Germany
Janne Repschläger
Climate Geochemistry Department, Max Planck Institute for Chemistry Mainz, 55128 Mainz, Germany
Daniel M. Sigman
Department of Geosciences, Princeton University, Princeton, NJ 08544, USA
Gerald H. Haug
Climate Geochemistry Department, Max Planck Institute for Chemistry Mainz, 55128 Mainz, Germany
Alfredo Martínez-García
Climate Geochemistry Department, Max Planck Institute for Chemistry Mainz, 55128 Mainz, Germany
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Short summary
This study uses foraminifera-bound nitrogen isotopes (FB-δ15N) to investigate photosymbiosis in planktic foraminifera. The analysis of South Atlantic shells, compared to a global dataset, shows that FB-δ15N distinguishes species with certain algal symbionts (dinoflagellates), likely due to internal ammonium recycling. However, the studied site stands out with its larger-than-expected FB-δ15N offsets, highlighting influences on FB-δ15N signatures in regions with strong environmental gradients.
This study uses foraminifera-bound nitrogen isotopes (FB-δ15N) to investigate photosymbiosis in...
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