Pelagic-benthic coupling within an upwelling system of the subtropical northeast Atlantic over the last 35kaBP

C. L. McKay*, H. L. Filipsson, O. E. Romero, J. B.W. Stuut, B. Donner

*Corresponding author for this work

Research output: Contribution to JournalArticleAcademicpeer-review


We present a high resolution, multiproxy study of the relationship between pelagic and benthic environments of a coastal upwelling system in the subtropical NE Atlantic Ocean. Marine sediments corresponding to late MIS3 to the Holocene in the radiocarbon dated core GeoB7926, retrieved off Mauritania (21°N) were analysed to reconstruct productivity in surface waters and its linkage to deep waters during the last 35kaBP. High latitude cold events and changes in atmospheric and oceanographic dynamics influenced upwelling intensity over this time period. Subsequently, this caused changes in primary productivity off this low-latitude coastal upwelling locality. The benthic foraminiferal fauna displays four main community shifts corresponding to fundamental climatic events, first of all during late MIS3 (35-28kaBP), secondly from 28 to 19kaBP (including Heinrich event 2 and the LGM), thirdly within Heinrich event 1, the Bølling Allerød and the Younger Dryas (18-11.5kaBP) and finally during the Holocene (11.5-0kaBP). In particular, strong pelagic-benthic coupling is apparent in MIS 3, as demonstrated by increased primary productivity, indicated by moderate DAR and the dominance of benthic foraminiferal species which prefer fresh phytodetritus. A decline in upwelling intensity and nutrient availability follows, which resulted in a proportionately larger amount of older, degraded matter, provoking a shift in the benthic foraminifera fauna composition. This rapid response of the benthic environment continues with a progressive increase in upwelling intensity due to sea level and oceanographic changes and according high surface production during the LGM. During Heinrich event 1 and the Younger Dryas, extreme levels of primary production actually hindered benthic environment through the development of low oxygen conditions. After this period, a final change in benthic foraminiferal community composition occurs which indicates a return to more oxygenated conditions during the Holocene.

Original languageEnglish
Pages (from-to)299-315
Number of pages17
JournalQuaternary Science Reviews
Publication statusPublished - 15 Dec 2014


  • Benthic foraminifera
  • Palaeoproductivity
  • Pelagic-benthic
  • Subtropical NE Atlantic
  • Upwelling


Dive into the research topics of 'Pelagic-benthic coupling within an upwelling system of the subtropical northeast Atlantic over the last 35kaBP'. Together they form a unique fingerprint.

Cite this