Dataset: Grazing experiment 6: pCO2 with and without grazing by Coxliella

The phytoplankton Rhodomonas sp. CCMP 755 was grown semi-continuously in atmosphere controlled chambers at three different CO2 treatment concentrations; Ambient (400ppmv), Moderate (750ppmv), and High (1000ppmv).  Cultures were diluted daily starting day 4 with pre-equilibrated media containing f/50 nutrients.  Some of the culture removed was used to evaluate chemical parameters. 

pCO2 Rhodomonas: Samples for total alkalinity were taken on growth days 1, 3, 5, 7, 11, 12, 13 and 17 and preserved with HgCl2 and stored at 4° until analysis.  Alkalinity was measured by gran titration using a Titrando 888, and 0.1 N HCl titrant, in a temperature controlled titration vessel.  DIC samples were filtered through a 0.2 µm nylon syringe filter on the morning of the experimental day, then stored in airtight vials at 4°C until analysis within 60 days using an Apollo SciTech DIC Analyzer AS-C3 which incorporates the LI-7000 CO2/H2O Analyzer. Other parameters were calculated with CO2sys.

pCO2 Rhodomonas and long-term grazing by Coxliella: Samples for total alkalinity of pre-equilibrated media were taken on growth day 11 and from the Rhodomonas plus Coxliella grazing treatments on day16 and preserved with HgCl2 and stored at 4° until analysis.  Alkalinity was measured by gran titration using a Titrando 888, and 0.1 N HCl titrant, in a temperature controlled titration vessel.  DIC samples from the long-term grazing experiment were filtered through a 0.2 µm nylon syringe filter on the morning of the experimental day, then stored in airtight vials at 4°C until analysis within 60 days using an Apollo SciTech DIC Analyzer AS-C3 which incorporates the LI-7000 CO2/H2O Analyzer. Other parameters were calculated with CO2sys.