Alkenone isotopes show evidence of active carbon concentrating mechanisms in coccolithophores as aqueous carbon dioxide concentrations fall below 7 µmol L −1
Coccolithophores and other haptophyte algae acquire the carbon required for metabolic processes from the water in which they live. Whether carbon is actively moved across the cell membrane via a carbon concentrating mechanism, or passively through diffusion, is important for haptophyte biochemistry....
Published in: | Biogeosciences |
---|---|
Main Author: | |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Copernicus Publications
2021
|
Subjects: | |
Online Access: | https://doi.org/10.5194/bg-18-1149-2021 https://doaj.org/article/bc08861bcad147f29a7b5c9872c9e629 |
id |
ftdoajarticles:oai:doaj.org/article:bc08861bcad147f29a7b5c9872c9e629 |
---|---|
record_format |
openpolar |
spelling |
ftdoajarticles:oai:doaj.org/article:bc08861bcad147f29a7b5c9872c9e629 2023-05-15T16:38:49+02:00 Alkenone isotopes show evidence of active carbon concentrating mechanisms in coccolithophores as aqueous carbon dioxide concentrations fall below 7 µmol L −1 M. P. S. Badger 2021-02-01T00:00:00Z https://doi.org/10.5194/bg-18-1149-2021 https://doaj.org/article/bc08861bcad147f29a7b5c9872c9e629 EN eng Copernicus Publications https://bg.copernicus.org/articles/18/1149/2021/bg-18-1149-2021.pdf https://doaj.org/toc/1726-4170 https://doaj.org/toc/1726-4189 doi:10.5194/bg-18-1149-2021 1726-4170 1726-4189 https://doaj.org/article/bc08861bcad147f29a7b5c9872c9e629 Biogeosciences, Vol 18, Pp 1149-1160 (2021) Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 article 2021 ftdoajarticles https://doi.org/10.5194/bg-18-1149-2021 2022-12-31T05:16:53Z Coccolithophores and other haptophyte algae acquire the carbon required for metabolic processes from the water in which they live. Whether carbon is actively moved across the cell membrane via a carbon concentrating mechanism, or passively through diffusion, is important for haptophyte biochemistry. The possible utilization of carbon concentrating mechanisms also has the potential to over-print one proxy method by which ancient atmospheric CO 2 concentration is reconstructed using alkenone isotopes. Here I show that carbon concentrating mechanisms are likely used when aqueous carbon dioxide concentrations are below 7 µ mol L −1 . I compile published alkenone-based CO 2 reconstructions from multiple sites over the Pleistocene and recalculate them using a common methodology, which allows comparison to be made with ice core CO 2 records. Interrogating these records reveals that the relationship between proxy CO 2 and ice core CO 2 breaks down when local aqueous CO 2 concentration falls below 7 µ mol L −1 . The recognition of this threshold explains why many alkenone-based CO 2 records fail to accurately replicate ice core CO 2 records, and it suggests the alkenone proxy is likely robust for much of the Cenozoic when this threshold was unlikely to be reached in much of the global ocean. Article in Journal/Newspaper ice core Directory of Open Access Journals: DOAJ Articles Biogeosciences 18 3 1149 1160 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 |
spellingShingle |
Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 M. P. S. Badger Alkenone isotopes show evidence of active carbon concentrating mechanisms in coccolithophores as aqueous carbon dioxide concentrations fall below 7 µmol L −1 |
topic_facet |
Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 |
description |
Coccolithophores and other haptophyte algae acquire the carbon required for metabolic processes from the water in which they live. Whether carbon is actively moved across the cell membrane via a carbon concentrating mechanism, or passively through diffusion, is important for haptophyte biochemistry. The possible utilization of carbon concentrating mechanisms also has the potential to over-print one proxy method by which ancient atmospheric CO 2 concentration is reconstructed using alkenone isotopes. Here I show that carbon concentrating mechanisms are likely used when aqueous carbon dioxide concentrations are below 7 µ mol L −1 . I compile published alkenone-based CO 2 reconstructions from multiple sites over the Pleistocene and recalculate them using a common methodology, which allows comparison to be made with ice core CO 2 records. Interrogating these records reveals that the relationship between proxy CO 2 and ice core CO 2 breaks down when local aqueous CO 2 concentration falls below 7 µ mol L −1 . The recognition of this threshold explains why many alkenone-based CO 2 records fail to accurately replicate ice core CO 2 records, and it suggests the alkenone proxy is likely robust for much of the Cenozoic when this threshold was unlikely to be reached in much of the global ocean. |
format |
Article in Journal/Newspaper |
author |
M. P. S. Badger |
author_facet |
M. P. S. Badger |
author_sort |
M. P. S. Badger |
title |
Alkenone isotopes show evidence of active carbon concentrating mechanisms in coccolithophores as aqueous carbon dioxide concentrations fall below 7 µmol L −1 |
title_short |
Alkenone isotopes show evidence of active carbon concentrating mechanisms in coccolithophores as aqueous carbon dioxide concentrations fall below 7 µmol L −1 |
title_full |
Alkenone isotopes show evidence of active carbon concentrating mechanisms in coccolithophores as aqueous carbon dioxide concentrations fall below 7 µmol L −1 |
title_fullStr |
Alkenone isotopes show evidence of active carbon concentrating mechanisms in coccolithophores as aqueous carbon dioxide concentrations fall below 7 µmol L −1 |
title_full_unstemmed |
Alkenone isotopes show evidence of active carbon concentrating mechanisms in coccolithophores as aqueous carbon dioxide concentrations fall below 7 µmol L −1 |
title_sort |
alkenone isotopes show evidence of active carbon concentrating mechanisms in coccolithophores as aqueous carbon dioxide concentrations fall below 7 µmol l −1 |
publisher |
Copernicus Publications |
publishDate |
2021 |
url |
https://doi.org/10.5194/bg-18-1149-2021 https://doaj.org/article/bc08861bcad147f29a7b5c9872c9e629 |
genre |
ice core |
genre_facet |
ice core |
op_source |
Biogeosciences, Vol 18, Pp 1149-1160 (2021) |
op_relation |
https://bg.copernicus.org/articles/18/1149/2021/bg-18-1149-2021.pdf https://doaj.org/toc/1726-4170 https://doaj.org/toc/1726-4189 doi:10.5194/bg-18-1149-2021 1726-4170 1726-4189 https://doaj.org/article/bc08861bcad147f29a7b5c9872c9e629 |
op_doi |
https://doi.org/10.5194/bg-18-1149-2021 |
container_title |
Biogeosciences |
container_volume |
18 |
container_issue |
3 |
container_start_page |
1149 |
op_container_end_page |
1160 |
_version_ |
1766029164854378496 |