Computer Science
Scientific paper
Oct 2006
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2006gecoa..70.4906c&link_type=abstract
Geochimica et Cosmochimica Acta, Volume 70, Issue 19, p. 4906-4920.
Computer Science
19
Scientific paper
Trace elements in calcareous organisms have been widely used for paleoclimatic studies. However, the factors controlling their incorporation into mollusc shells are still unclear. We studied here the Sr, Mg, Ba and Mn serial records in the shells of two aragonitic marine bivalve species: Mesodesma donacium and Chione subrugosa from the Peruvian Coast. The elemental concentrations were compared to local temperature and salinity records. The relationships with crystal growth rate G were investigated thanks to well defined periodic growth structures providing a precise shell chronology. Our results show that for both species, environmental parameters only have minor influence, whereas crystal growth rate strongly influences trace elements concentrations, especially for Sr (explaining up to 74% of the variance). The relationship between G and Sr/Ca exhibits variability among the shells as well as inside the shells. For a same growth rate value, Sr/Ca values are higher in more curved shell sections, and the growth rate influence is stronger as well. We show that intercellular and Ca2+-pump pathways cannot support the calcification Ca2+ flux, leading us to propose an alternative mechanism for ionic transport through the calcifying mantle, implying a major role for calcium channels on mantle epithelial cell membranes. In this new calcification model, Sr/Ca shell ratios is determined by Ca2+-channel selectivity against Sr2+, which depends (i) on the electrochemical potential imposed by the crystallisation process and (ii) on the Ca2+-channel density per surface unit on mantle epithelia.
Barrett Nicholas T.
Bentaleb Ilhem
Bruguier Olivier
Carré Matthieu
Fontugne Michel
No associations
LandOfFree
Calcification rate influence on trace element concentrations in aragonitic bivalve shells: Evidences and mechanisms does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Calcification rate influence on trace element concentrations in aragonitic bivalve shells: Evidences and mechanisms, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Calcification rate influence on trace element concentrations in aragonitic bivalve shells: Evidences and mechanisms will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-905594