δ13C in Mytilus edulis shells: relation to salinity, DIC, phytoplankton and metabolism - CNRS - Centre national de la recherche scientifique Accéder directement au contenu
Article Dans Une Revue Organic Geochemistry Année : 2006

δ13C in Mytilus edulis shells: relation to salinity, DIC, phytoplankton and metabolism

Résumé

Bivalve shells can potentially record the carbon isotopic signature of the dissolved inorganic carbon (δ13CDIC) in estuarine waters, thereby providing information about past estuarine biogeochemical cycles. However, the fluid from which these animals calcify is a ‘pool' of metabolic CO2 and external dissolved inorganic carbon (DIC). The incorporation of respired 13C depleted carbon into the skeletons of aquatic invertebrates is well documented, and may affect the 13CDIC record of the skeleton. Typically, less than 10 % of the carbon in the skeleton is metabolic in origin, although higher amounts have been reported. If this small offset is more or less constant, large biogeochemical gradients in estuaries may be recorded in the δ13C value of bivalve shells. In this study, it is assessed if the δ13C values of Mytilus edulis shells can be used as a proxy of δ13CDIC as well as provide an indication of salinity. First, the δ13C values of respired CO2 (δ13CR) was considered using the δ13C values of soft tissues as a proxy for δ13CR. Along the strong biogeochemical gradient of the Scheldt estuary (The Netherlands – Belgium), δ13CR was linearly related to δ13CDIC (r2 = 0.87), which in turn was linearly related to salinity (r2 = 0.94). The mussels were highly selective, assimilating most of their carbon from phytoplankton out of the total particulate organic carbon (POC) pool. However, on a seasonal basis, tissue δ13C varied differently than δ13CDIC and δ13CPOC, most likely due to lipid content of the tissue. All shells contained less than 10 % metabolic C, but ranged from near zero to 10 %, thus excluding the use of δ13C in these shells as a robust δ13CDIC or salinity proxy. As an example, an error in salinity of about five would have been made at one site. Nevertheless, large changes in δ13CDIC (>2 ‰) can be determined using M. edulis shell δ13C.
Fichier principal
Vignette du fichier
Gillikin_et_al_OG_Revised.pdf (295.4 Ko) Télécharger le fichier
Origine : Fichiers produits par l'(les) auteur(s)
Loading...

Dates et versions

hal-00452789 , version 1 (03-02-2010)

Identifiants

Citer

David Paul Gillikin, Anne Lorrain, S. Bouillon, F. Dehairs, Philippe Willenz. δ13C in Mytilus edulis shells: relation to salinity, DIC, phytoplankton and metabolism. Organic Geochemistry, 2006, 37 (10), pp.1371-1382. ⟨hal-00452789⟩
293 Consultations
191 Téléchargements

Partager

Gmail Facebook X LinkedIn More