| Registro completo |
| Provedor de dados: |
ArchiMer
|
| País: |
France
|
| Título: |
Oxygen isotope disequilibrium in the juvenile portion of oyster shells biases seawater temperature reconstructions
|
| Autores: |
Huyghe, Dimitri
Emmanuel, Laurent
De Rafelis, Marc
Renard, Maurice
Ropert, Michel
Labourdette, Nathalie
Lartaud, Franck
|
| Data: |
2020-08
|
| Ano: |
2020
|
| Palavras-chave: |
Stable isotopes
Paleoclimatology
Sclerogeochemistry
Sclerochronology
Kinetic isotope effect
|
| Resumo: |
For decades, bivalve shells have constituted one of the most common supports for paleoclimatic archives based on stable isotope approaches. In this work, we conducted chemical marking and recapture techniques to study the fluctuation of δ18O values of oyster shells of the species Magallana gigas reared in natural environment in Normandy (France) for two years. The results were compared to the continuous monitoring of temperature and salinity and monthly records of seawater δ18O. Isotopic measurements were performed on the hinge area that regroups the whole life of the oysters. Here we demonstrate that oysters mineralized their shells with no significant growth breaks during the two-years experiment, even at temperatures below 6 °C. The results confirm that adult oysters (i.e. > 1 yr) mineralized their shells at equilibrium. However, juvenile specimens exhibit a strong isotopic disequilibrium, with a maximum shift of the δ18O values of 3‰ in winter, likely due to kinetic isotope effects. This corresponds to a reconstructed temperature up to 13 °C warmer than expected. This work indicates that although these oyster shells can be used as an accurate archive of (paleo)environmental conditions, the shell portion mineralized during the juvenile stage (i.e. < 1 yr) should be avoided for paleotemperature reconstructions. Given the wide use of bivalve shells as environmental archives, similar studies on others species are required.
|
| Tipo: |
Text
|
| Idioma: |
Inglês
|
| Identificador: |
https://archimer.ifremer.fr/doc/00624/73622/73038.pdf
DOI:10.1016/j.ecss.2020.106777
https://archimer.ifremer.fr/doc/00624/73622/
|
| Editor: |
Elsevier BV
|
| Formato: |
application/pdf
|
| Fonte: |
Estuarine Coastal And Shelf Science (0272-7714) (Elsevier BV), 2020-08 , Vol. 240 , P. 106777 (8p.)
|
| Direitos: |
info:eu-repo/semantics/openAccess
restricted use
|
|
