TY  - JOUR
A1  - Schleinkofer, Nicolai
A1  - Raddatz, Jacek
A1  - Evans, David
A1  - Gerdes, Axel
A1  - Flögel, Sascha
A1  - Voigt, Silke
A1  - Büscher, Janina
A1  - Wisshak, Max
T1  - Compositional variability of Mg/Ca, Sr/Ca, and Na/Ca in the deep-sea bivalve Acesta excavata (Fabricius, 1779)
T2  - PLOS ONE
N2  - Acesta excavata (Fabricius, 1779) is a slow growing bivalve from the Limidae family and is often found associated with cold-water coral reefs along the European continental margin. Here we present the compositional variability of frequently used proxy elemental ratios (Mg/ Ca, Sr/Ca, Na/Ca) measured by laser-ablation mass spectrometry (LA-ICP-MS) and com- pare it to in-situ recorded instrumental seawater parameters such as temperature and salin- ity. Shell Mg/Ca measured in the fibrous calcitic shell section was overall not correlated with seawater temperature or salinity; however, some samples show significant correlations with temperature with a sensitivity that was found to be unusually high in comparison to other marine organisms. Mg/Ca and Sr/Ca measured in the fibrous calcitic shell section display significant negative correlations with the linear extension rate of the shell, which indicates strong vital effects in these bivalves. Multiple linear regression analysis indicates that up to 79% of elemental variability is explicable with temperature and salinity as independent pre- dictor values. Yet, the overall results clearly show that the application of Element/Ca (E/Ca) ratios in these bivalves to reconstruct past changes in temperature and salinity is likely to be complicated due to strong vital effects and the effects of organic material embedded in the shell. Therefore, we suggest to apply additional techniques, such as clumped isotopes, in order to exactly determine and quantify the underlying vital effects and possibly account for these. We found differences in the chemical composition between the two calcitic shell lay- ers that are possibly explainable through differences of the crystal morphology. Sr/Ca ratios also appear to be partly controlled by the amount of magnesium, because the small magne- sium ions bend the crystal lattice which increases the space for strontium incorporation. Oxi- dative cleaning with H2O2 did not significantly change the Mg/Ca and Sr/Ca composition of the shell. Na/Ca ratios decreased after the oxidative cleaning, which is most likely a leaching effect and not caused by the removal of organic matter.
KW  - Bivalves
KW  - Reefs
KW  - Salinity
KW  - Coral reefs
KW  - Organic materials
KW  - Calcite
KW  - Crystals
KW  - Ocean temperature
Y1  - 2021
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/61334
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-613347
SN  - 1932-6203
VL  - 16
IS  - 4, art. e0245605
SP  - 1
EP  - 24
PB  - Public Library of Science
CY  - San Francisco
ER  -