SURFACE HYDROGRAPHY AND PHYTOPLANKTON OF THE BRAZIL-MALVINAS CURRENTSCONFLUENCE

Results are presented on the phytoplankton species composition and abu ndance from bottle samples collected in September 1989 near the conflu ence of the Brazil and Malvinas currents off Argentina. The phytoplank ton assemblages were dominated by diatoms and dinoflagellates. A surfa ce diatom bloom was found along the west side of the Brazil Current, a nd was dominated by Thalassiosira delicatula Ostenfeld emend. Hasle (c ell numbers up to 5.5 x 10(6) C cells l(-1)). The bloom was associated with strong temperature gradients separating Brazil and Malvinas wate rs, and with the presence of a cyclonic eddy near the confluence of th e currents. These features were detected in satellite imagery coincide nt with the in situ sampling dates.