© Springer-Verlag 1986 Near Surface Nutrient and Phytoplankton Distribution in the Drake Passage during Early December

• Main Authors: Ulrich Sommer I, Hans-henning Stabel
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 1985
• Subjects: Drake Passage; Antarc*
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.477.4967; http://oceanrep.geomar.de/14152/1/fulltext.pdf

Summary. Nutr ient concentrat ions and phytop lankton species composi t ion in near surface samples were studied along a S-N gradient in the Drake Passage in early De-cember 1984. Nitrate concentrat ions were much lower than usual ly previously reported f rom circum-Antarct ic waters. Compar ison of dissolved nutr ient concentrat ions with growth requirements of Antarct ic p lankton algae suggests potent ial l imitat ion f at least some species by nitrate or silicate. The taxonomic composi t ion of the phytop lankton i our samples seemed to be part ia l ly con-trol led by compet i t ion for l imiting nutrients. mediately filtered (0,1 Ixm pore-size) and deep frozen. The storage time was about 5 months. Analyses of soluble reactive phosphorus, nitrate, nitrite, ammonium and soluble reactive silicate were performed accord-ing to oceanographic standard methods (Strickland and Parsons 1972) with a Technicon-autoanalyzer. Nit ite and ammonium were found nearly indetectable. Samples for cell counts were fixed by glutardi-aldehyde and 250 ml were filtered on a 0.45 Ixm membrane filter, which was made transparent for microscopy by immersion oil. Biomass was estimated as cell volume (no correction for vacuoles) after approxima-tion to standard geometric solids. Results