TY - JOUR
T1 - Distinct responses of planktonic foraminiferal B/Ca to dissolution on seafloor
AU - Dai, Yuhao
AU - Yu, Jimin
AU - Johnstone, Heather J.H.
N1 - Publisher Copyright:
© 2016. American Geophysical Union. All Rights Reserved.
PY - 2016/4/1
Y1 - 2016/4/1
N2 - We have measured B/Ca in four core-top planktonic foraminiferal species (Globigerinoides ruber (white), Globigerinoides sacculifer (without final sac-like chamber), Neogloboquadrina dutertrei, and Pulleniatina obliquiloculata) from three depth transects (the Caribbean Sea, the southwestern Indian Ocean, and the Ontong Java Plateau) to evaluate the effect of dissolution on planktonic foraminiferal B/Ca. At each transect, G. ruber (w) and G. sacculifer (w/o sac) show decreasing B/Ca with increasing water depth. This decrease in B/Ca is accompanied with decreases in shell weights, Mg/Ca, and bottom water calcite saturation state. This indicates a postdepositional dissolution effect on B/Ca in these two species. The strong correlation observed between changes in B/Ca and bottom water calcite saturation state offers an approach to correcting for the dissolution bias. By contrast, B/Ca in N. dutertrei and P. obliquiloculata remains unchanged along depth transects, although shell weights and Mg/Ca display significant declines. Overall, our core-top results suggest species-specific dissolution effects on B/Ca in different planktonic foraminiferal species.
AB - We have measured B/Ca in four core-top planktonic foraminiferal species (Globigerinoides ruber (white), Globigerinoides sacculifer (without final sac-like chamber), Neogloboquadrina dutertrei, and Pulleniatina obliquiloculata) from three depth transects (the Caribbean Sea, the southwestern Indian Ocean, and the Ontong Java Plateau) to evaluate the effect of dissolution on planktonic foraminiferal B/Ca. At each transect, G. ruber (w) and G. sacculifer (w/o sac) show decreasing B/Ca with increasing water depth. This decrease in B/Ca is accompanied with decreases in shell weights, Mg/Ca, and bottom water calcite saturation state. This indicates a postdepositional dissolution effect on B/Ca in these two species. The strong correlation observed between changes in B/Ca and bottom water calcite saturation state offers an approach to correcting for the dissolution bias. By contrast, B/Ca in N. dutertrei and P. obliquiloculata remains unchanged along depth transects, although shell weights and Mg/Ca display significant declines. Overall, our core-top results suggest species-specific dissolution effects on B/Ca in different planktonic foraminiferal species.
KW - B/Ca
KW - dissolution
KW - planktonic foraminifera
UR - http://www.scopus.com/inward/record.url?scp=84963623642&partnerID=8YFLogxK
U2 - 10.1002/2015GC006199
DO - 10.1002/2015GC006199
M3 - Article
SN - 1525-2027
VL - 17
SP - 1339
EP - 1348
JO - Geochemistry, Geophysics, Geosystems
JF - Geochemistry, Geophysics, Geosystems
IS - 4
ER -