Seawater carbonate chemistry and biological processes during experiments with Limacina helicina, 2009

• Main Authors: Comeau, Steeve, Jeffree, Ross, Teyssié, Jean-Louis, Gattuso, Jean-Pierre
• Format: Dataset
• Language: English
• Published: PANGAEA 2010
• Subjects: Alkalinity; Gran titration (Gran; 1950); total; Animalia; Aragonite saturation state; Arctic; Behaviour; Bicarbonate ion; Calcification/Dissolution; Calcite saturation state; Calcium carbonate passive adsorption; standard deviation; Calcium carbonate precipitated; Calculated; Calculated using seacarb after Nisumaa et al. (2010); Carbon; inorganic; dissolved; Carbonate ion; Carbonate system computation flag; Carbon dioxide; Containers and aquaria (20-1000 L or < 1 m**2); EPOCA; EUR-OCEANS; European network of excellence for Ocean Ecosystems Analysis; European Project on Ocean Acidification; Experimental treatment; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Gut clearance coefficient; Identification; Limacina helicina; Mollusca; OA-ICC; Ocean Acidification International Coordination Centre; Open ocean; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); Pelagos; pH; pH meter (Metrohm; 826 pH mobile); Polar; Respiration; Respiration rate; oxygen; arctic pteropods; Ocean acidification; Zooplankton
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.744720; https://doi.org/10.1594/PANGAEA.744720

Thecosome pteropods (pelagic mollusks) can play a key role in the food web of various marine ecosystems. They are a food source for zooplankton or higher predators such as fishes, whales and birds that is particularly important in high latitude areas. Since they harbor a highly soluble aragonitic shell, they could be very sensitive to ocean acidification driven by the increase of anthropogenic CO2 emissions. The effect of changes in the seawater chemistry was investigated on Limacina helicina, a key species of Arctic pelagic ecosystems. Individuals were kept in the laboratory under controlled pCO2 levels of 280, 380, 550, 760 and 1020 µatm and at control (0°C) and elevated (4°C) temperatures. The respiration rate was unaffected by pCO2 at control temperature, but significantly increased as a function of the pCO2 level at elevated temperature. pCO2 had no effect on the gut clearance rate at either temperature. Precipitation of CaCO3, measured as the incorporation of 45Ca, significantly declined as a function of pCO2 at both temperatures. The decrease in calcium carbonate precipitation was highly correlated to the aragonite saturation state. Even though this study demonstrates that pteropods are able to precipitate calcium carbonate at low aragonite saturation state, the results support the current concern for the future of Arctic pteropods, as the production of their shell appears to be very sensitive to decreased pH. A decline of pteropod populations would likely cause dramatic changes to various pelagic ecosystems.