Seawater carbonate chemistry and biological processes during experiments with haploid and diploid life stages of Emiliania huxleyi, Calcidiscus leptoporus and Syracosphaera pulchra

• Main Authors: Fiorini, Sarah, Middelburg, Jack J, Gattuso, Jean-Pierre
• Format: Dataset
• Language: English
• Published: PANGAEA 2010
• Subjects: Alkalinity; total; Aragonite saturation state; Bicarbonate ion; Biomass/Abundance/Elemental composition; Bottles or small containers/Aquaria (<20 L); Calcidiscus leptoporus; Calcite saturation state; Calculated; Calculated using seacarb after Nisumaa et al. (2010); Carbon; inorganic; dissolved; particulate; per cell; organic; Carbon/Nitrogen ratio; Carbonate ion; Carbonate system computation flag; Carbon dioxide; Chromista; Coulometric titration; Emiliania huxleyi; EPOCA; EUR-OCEANS; European network of excellence for Ocean Ecosystems Analysis; European Project on Ocean Acidification; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Growth/Morphology; Growth rate; Haptophyta; Laboratory experiment; Laboratory strains; Mass spectrometer Thermo Electron Flash EA 1122 Analyzer; Nitrogen; Nitrogen per cell; Not applicable; Ocean acidification
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.733912; https://doi.org/10.1594/PANGAEA.733912

The response of Emiliania huxleyi (Lohmann), Calcidiscus leptoporus (Murray and Blackman), and Syracosphaera pulchra (Lohmann) to elevated partial pressure of carbon dioxide (pCO2) was investigated in batch cultures. For the first time, we reported on the response of the non-calcifying (haploid) life stage of these three species. Growth rate, cell size, particulate inorganic (PIC) and particulate organic carbon (POC) of both life stages were measured at two different pCO2 (400 and 760 ppm) and their organic and inorganic carbon production calculated. The two life stages within the same species generally exhibited a similar response to elevated pCO2, the response of the haploid stage being often more pronounced than that of the diploid stage. The growth rate was consistently higher at elevated pCO2 but the response of other processes varied among species. Calcification rate of C. leptoporus and of S. pulchra did not change at elevated pCO2 while it increased in E. huxleyi. Particulate organic carbon production and cell size of both life stages of S. pulchra and of the haploid stage of E. huxleyi markedly decreased at elevated pCO2. It remained unaltered in the diploid stage of E. huxleyi and C. leptoporus and increased in the haploid stage of the latter. The PIC:POC ratio increased in E. huxleyi and was constant in C. leptoporus and S. pulchra. Elevated pCO2 has a significant effect on these three coccolithophores species, the haploid stage being more sensitive. This must be taken into account when predicting the fate of coccolithophores in the future ocean.