Cell counts: Ruegeria pomeroyi, Thalassiosira pseudonana, and Alexandrium tamarense cells were measured using a flow cytometer.
DIN: Cadmium reduction method; Nitrate is measured by reducing it to nitrite in an alkaline-buffered solution passing through a column of copper-cadmium metal filings and then measuring nitrite by diazotizing with sulfanilamide and coupling with N-(1-naphthyl)-ethylenediamine dihydrochloride to form a pink colored azo dye which is measured colorimetrically. Instrument: Alpkem and Astoria-Pacific Autoanalyzers
DIP: Orthophosphate method; PO4 is measured colorimetrically as an antimony-phospho-molybdate complex (APHA 4500-P F) that is reduced to an intensely blue-colored complex by ascorbic acid. Instrument: Alpkem and Astoria-Pacific Autoanalyzers
DOC: Combustion method; Total dissolved carbon and dissolved inorganic carbon are determined by combustion of an unacidified and acidified 0.2 micron filtered subsamples. DOC concentration is calculated by subtracting the DIC concentration from the TDC concentration. Instrument: Shimadzu TOC-5000A Total Organic Carbon Analyzer
TOC: Combustion method; Total organic carbon is determined by combustion of an unacidified and unfiltered sample. Instrument: Shimadzu TOC-5000A Total Organic Carbon Analyzer
DMSP: See: Rellinger, A., et al. Occurrence and turnover of DMSP and DMS in deep waters of the Ross Sea, Antarctica. Deep-Sea Research I 56 (2009) 686–702. doi:10.1016/j.dsr.2008.12.010