COMPOSITION OF ULTRAPHYTOPLANKTON IN THE CENTRAL NORTH-ATLANTIC

In the central North Atlantic Ocean, the ultraphytoplankton averaged o ver depth and season comprises 78% Prochlorococcus spp., 12% Synechoco ccus spp. and 10% eukaryotic algae by numbers. However, on the basis o f Light scatter (a substitute for carbon biomass), the average percent ages are 11, 2 and 87% respectively. On the basis of red fluorescence (a substitute for chlorophyll biomass), the average percentages are 28 , 11 and 61% respectively. On the basis of primary productivity, the a verage percentages are 19, 13 and 68% respectively. Thus, eukaryotic a lgae dominate the biomass and productivity oi ultraphytoplankton.