Abstract

Benthic foraminiferal thanatocoenoses were studied in 29 sediment surface samples off NW Africa, between 19° and 27°N, and from water depths between 506 and 3314 m. The results were compared with estimated values of the downward organic flux and measured bottom water oxygen concentrations. Although the latter 2 parameters show a strong negative correlation in the study area, we argue that the organic flux is the main controlling ecological factor. On the basis of an R-mode multivariate statistical analysis, 6 species clusters are recognized, which are separated geographically by differences in organic flux and water depth. The combined sample scores on the first 2 principal component axes show a strong positive correlation with the estimated downward organic flux (R2 = 0.83). It is suggested that this relationship can be used on a local scale as a proxy for paleo-export production, as long as bottom water oxygenation does not fall below a critical level.

You do not currently have access to this article.