Exploring the use of compound-specific carbon isotopes as a palaeoproductivity proxy off the coast of Adélie Land, East Antarctica - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Biogeosciences Année : 2021

Exploring the use of compound-specific carbon isotopes as a palaeoproductivity proxy off the coast of Adélie Land, East Antarctica

Résumé

The Antarctic coastal zone is an area of high primary productivity, particularly within coastal polynyas, where large phytoplankton blooms and drawdown of CO2 occur. Reconstruction of historical primary productivity changes and the associated driving factors could provide baseline insights on the role of these areas as sinks for atmospheric CO2 , especially in the context of projected changes in coastal Antarctic sea ice. Here we investigate the potential for using carbon isotopes (δ13C) of fatty acids in marine sediments as a proxy for primary productivity. We use a highly resolved sediment core from off the coast of Adélie Land spanning the last ∼ 400 years and monitor changes in the concentrations and δ13C of fatty acids along with other proxy data from the same core. We discuss the different possible drivers of their variability and argue that C24fatty acid δ13C predominantly reflects phytoplankton productivity in openwater environments, while C18 fatty acid δ13C reflects productivity in the marginal ice zone. These new proxies have implications for better understanding carbon cycle dynamics in the Antarctica coastal zone in future palaeoclimate studies.
Fichier principal
Vignette du fichier
Ashley_BG2021.pdf (1.44 Mo) Télécharger le fichier
Origine : Fichiers éditeurs autorisés sur une archive ouverte

Dates et versions

hal-03378695 , version 1 (14-10-2021)

Identifiants

Citer

Kate E. Ashley, Xavier Crosta, Johan Etourneau, Philippine Campagne, Harry Gilchrist, et al.. Exploring the use of compound-specific carbon isotopes as a palaeoproductivity proxy off the coast of Adélie Land, East Antarctica. Biogeosciences, 2021, pp.5555-5571. ⟨10.5194/bg-18-5555-2021⟩. ⟨hal-03378695⟩
66 Consultations
44 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More