CONCLUSIONS

The agreement between BFAR and other paleoproductivity proxies supports the reliability of BFAR (>150 Ám) as an estimator of paleoproductivity at Site 1079. In general, the benthic foraminiferal assemblage is characterized by species preferring a high organic flux and for which oxygen is not a seriously limiting factor (as long as some free oxygen is available). High BFAR values and dominance of infaunal species during glacials reflect low-oxygen bottom-water conditions and high flux of organic matter. The presence of epifauna and decrease of infauna and BFAR during interglacials suggests more oxygenated conditions and lower productivity. Differences in the distribution of B. pseudopunctata and B. dilatata (the dominant species) could be explained in terms of preferences for amount and/or type of organic flux. Variations in BF/g at Site 1079 occur at 100- and 23-k.y. periodicities. Power in these frequency bands is presumably tied to precessional insolation forcing and the responding trade and monsoon wind systems, as suggested in previous studies from the eastern Angola Basin (Schneider et al., 1995).

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