The aim of my doctoral thesis is to reconstruct productivity and climate variation in the upwelling area of Mauritania (NW Africa) during the late Quaternary. Benthic foraminiferal thanatocoenoses have been studied in sediment surface samples. The results have been compared with estimated values of the downward organic flux and measured bottom water oxygen concentrations. The relationship between ecological factors and the microbenthic fauna 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. These results were applied to the results of two sediment cores from the continental slope in the northwest African upwelling system. Micropaleontological analysis reveals striking variation in the planktonic and benthic foraminiferal assemblages. These fluctuations are investigated to assess changes in the intensity and the position of the upwelling cells during the last 90 Kyears.

e.mail address: c.morigi@univpm.it