Influence of seasonal primary productivity on δ13C of North Atlantic deep-sea benthic foraminifera

The stable isotopic composition of benthic foraminifera has been widely used to reconstruct deep-ocean circulation, but questions have been raised about the influence of organic carbon flux on the carbon isotopic composition of deep-sea taxa. We show that annual and seasonality of primary productivity in the North Atlantic do not affect δ¹³C of Planulina wuellerstorfi, but that the intermittency or seasonality of primary production has a significant effect (0.9‰ change over 60° latitude) on δ¹³C of Epistominella exigua, reflecting the influence of pelagic-benthic coupling and microhabitat preferences on test geochemistry. These results support the use of δ¹³C of P. wuellerstorfi in paleocirculation studies and suggest that the δ¹³C of E. exigua can be used to reconstruct seasonality of productivity. © 2006 Elsevier Ltd. All rights reserved.

Duke Scholars

Author Bruce Corliss Earth and Climate Sciences