Impact of seawater carbonate chemistry on the calcification of marine bivalves, supplement to: Thomsen, Jörn; Haynert, Kristin; Wegner, K Mathias; Melzner, Frank (2015): Impact of seawater carbonate chemistry on the calcification of marine bivalves. Biogeosciences, 12(14), 4209-4220

• Main Authors: Thomsen, Jörn, Haynert, Kristin, Wegner, K Mathias, Melzner, Frank
• Format: Dataset
• Language: English
• Published: PANGAEA - Data Publisher for Earth & Environmental Science 2015
• Subjects: Animalia; Baltic Sea; Benthic animals; Benthos; Bottles or small containers/Aquaria <20 L; Coast and continental shelf; Growth/Morphology; Laboratory experiment; Mollusca; Mytilus edulis; Pelagos; Single species; Temperate; Zooplankton; Type; Species; Registration number of species; Uniform resource locator/link to reference; Experiment; Life stage; Figure; Treatment; Mass; Mass, standard deviation; Shell length; Shell length, standard deviation; Ratio; Carbon, inorganic, dissolved; Carbon, inorganic, dissolved, standard deviation; pH; pH, standard deviation; Bicarbonate ion; Bicarbonate ion, standard deviation; Partial pressure of carbon dioxide water at sea surface temperature wet air; Partial pressure of carbon dioxide, standard deviation; Carbonate ion; Carbonate ion, standard deviation; Aragonite saturation state; Aragonite saturation state, standard deviation; Percentage; Salinity; Salinity, standard deviation; Temperature, water; Temperature, water, standard deviation; Alkalinity, total; Alkalinity, total, standard deviation; Carbonate system computation flag; Carbon dioxide; Fugacity of carbon dioxide water at sea surface temperature wet air; Calcite saturation state; Potentiometric; Calculated using CO2SYS; Calculated using seacarb after Nisumaa et al. 2010; Ocean Acidification International Coordination Centre OA-ICC; Thomsen; Ocean acidification
• Online Access: https://dx.doi.org/10.1594/pangaea.862531; https://doi.pangaea.de/10.1594/PANGAEA.862531

Bivalve calcification, particularly of the early larval stages, is highly sensitive to the change in ocean carbonate chemistry resulting from atmospheric CO2 uptake. Earlier studies suggested that declining seawater [CO32−] and thereby lowered carbonate saturation affect shell production. However, disturbances of physiological processes such as acid-base regulation by adverse seawater pCO2 and pH can affect calcification in a secondary fashion. In order to determine the exact carbonate system component by which growth and calcification are affected it is necessary to utilize more complex carbonate chemistry manipulations. As single factors, pCO2 had no effects and [HCO3-] and pH had only limited effects on shell growth, while lowered [CO32−] strongly impacted calcification. Dissolved inorganic carbon (CT) limiting conditions led to strong reductions in calcification, despite high [CO32−], indicating that [HCO3-] rather than [CO32−] is the inorganic carbon source utilized for calcification by mytilid mussels. However, as the ratio [HCO3-] / [H+] is linearly correlated with [CO32−] it is not possible to differentiate between these under natural seawater conditions. An equivalent of about 80 μmol kg−1 [CO32−] is required to saturate inorganic carbon supply for calcification in bivalves. Below this threshold biomineralization rates rapidly decline. A comparison of literature data available for larvae and juvenile mussels and oysters originating from habitats differing substantially with respect to prevailing carbonate chemistry conditions revealed similar response curves. This suggests that the mechanisms which determine sensitivity of calcification in this group are highly conserved. The higher sensitivity of larval calcification seems to primarily result from the much higher relative calcification rates in early life stages. In order to reveal and understand the mechanisms that limit or facilitate adaptation to future ocean acidification, it is necessary to better understand the physiological processes and their underlying genetics that govern inorganic carbon assimilation for calcification. : In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2015) was used to compute a complete and consistent set of carbonate system variables, as described by Nisumaa et al. (2010). In this dataset the original values were archived in addition with the recalculated parameters (see related PI). The date of carbonate chemistry calculation is 2016-07-04.