@article{fdi:010040633,
  title = {{A} large metabolic carbon contribution to the delta {C}-13 record in marine aragonitic bivalve shells},
  author = {{G}illikin, {D}. {P}. and {L}orrain, {A}nne and {M}eng, {L}. and {D}ehairs, {F}.},
  editor = {},
  language = {{ENG}},
  abstract = {{I}t is well known that the incorporation of isotopically light metabolic carbon ({C}m) significantly affects the stable carbon isotope (delta {C}-13) signal recorded in biogenic carbonates. {T}his can obscure the record of delta {C}-13 of seawater dissolved inorganic carbon (delta {C}-13({DIC})) potentially archived in the shell carbonate. {T}o assess the {C}m contribution to {M}ercenaria mercenaria shells collected in {N}orth {C}arolina, {USA}, we sampled seawater delta {C}-13({DIC}), tissue, hemolymph and shell delta {C}-13. {A}ll shells showed an ontogenic decrease in shell delta {C}-13, with as much as a 4%. decrease over the lifespan of the clam. {T}here was no apparent ontogenic change in food source indicated by soft tissue delta {C}-13 values, therefore a change in the respired delta {C}-13 value cannot be the cause of this decrease. {H}emolymph delta {C}-13, on the other hand, did exhibit a negative relationship with shell height indicating that respired {CO}2 does influence the delta {C}-13 value of internal fluids and that the amount of respired {CO}2 is related to the size or age of the bivalve. {T}he percent metabolic {C} incorporated into the shell (%{C}-{M}) was significantly higher (up to 37%, with a range from 5% to 37%) than has been found in other bivalve shells, which usually contain less than 10%{C}-{M}. {I}nterestingly, the hemolymph did contain less than 10%{C}-{M}, suggesting that complex fractionation might occur between hemolymph and calcifying fluids. {S}imple shell biometrics explained nearly 60% of the observed variability in %{C}-{M}, however, this is not robust enough to predict %{C}-{M} for fossil shells. {T}hus, the metabolic effect on shell delta {C}-13 cannot easily be accounted for to allow reliable delta {C}-13({DIC}) reconstructions. {H}owever, there does seem to be a common effect of size, as all sites had indistinguishable slopes between the %{C}m and shell height (+0.19% per mm of shell height).},
  keywords = {},
  booktitle = {},
  journal = {{G}eochimica et {C}osmochimica {A}cta},
  volume = {71},
  numero = {12},
  pages = {2936--2946},
  ISSN = {0016-7037},
  year = {2007},
  DOI = {10.1016/j.gca.2007.04.003},
  URL = {https://www.documentation.ird.fr/hor/fdi:010040633},
}