Seawater carbonate chemistry and processes during experiments with Emiliania huxleyi (2005 Bergen) and Coccolithus braarudii (RCC 1200), 2010

• Main Authors: Müller, Marius N, Schulz, Kai Georg, Riebesell, Ulf
• Format: Dataset
• Language: English
• Published: PANGAEA 2010
• Subjects: Alkalinity; total; Aragonite saturation state; Bicarbonate ion; BIOACID; Biological Impacts of Ocean Acidification; Biomass/Abundance/Elemental composition; Bottles or small containers/Aquaria (<20 L); Calcite saturation state; Calculated; Calculated using seacarb after Nisumaa et al. (2010); Carbon; inorganic; dissolved; organic/Nitrogen; total ratio; Carbonate ion; Carbonate system computation flag; Carbon dioxide; Chromista; Coccolithus braarudii; Emiliania huxleyi; EPOCA; EUR-OCEANS; European network of excellence for Ocean Ecosystems Analysis; European Project on Ocean Acidification; Experimental treatment; Experiment day; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Growth/Morphology; Growth rate; Haptophyta; Laboratory experiment; Laboratory strains; Light:Dark cycle; Metrohm Titrando titrator; Nitrite; Not applicable; OA-ICC; Ocean Acidification International Coordination Centre; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); Particulate inorganic carbon/particulate organic carbon ratio; Particulate inorganic carbon/total particulate nitrogen ratio; Pelagos; pH; Phosphate; Phytoplankton; Radiation; photosynthetically active; Ocean acidification
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.744738; https://doi.org/10.1594/PANGAEA.744738

The physiological performance of two coccolithophore species,Emiliania huxleyi and Coccolithus braarudii, was investigated during long-term exposure to elevated pCO2 levels. Mono-specific cultures were grown over 152 (E. huxleyi) and 65 (C. braarudii) generations while pCO2 was gradually increased to maximum levels of 1150 ?atm (E. huxleyi) and 930 ?atm (C. braarudii) and kept constant thereafter. Rates of cell growth and cell quotas of particulate organic carbon (POC), particulate inorganic carbon (PIC) and total particulate nitrogen (TPN) were determined repeatedly throughout the incubation period. Increasing pCO2 caused a decrease in cell growth rate of 9% and 29% in E. huxleyi and C. braarudii, respectively. In both species cellular PIC:TPN and PIC:POC ratios decreased in response to rising pCO2, whereas no change was observed in the POC:TPN ratios of E. huxleyi and C. braarudii. These results are consistent with those obtained in shorter-term high CO2exposure experiments following abrupt pertubations of the seawater carbonate system and indicate that for the strains tested here a gradual CO2 increase does not alleviate CO2/pH sensitivity.