Seawater carbonate chemistry and shell thickness, shell dissolution of Limacina helicina pteropods

• Main Authors: Mekkes, Lisette, Renema, Willem, Alin, Simone R, Feely, Richard A, Huisman, Jef, Roessingh, Peter, Peijnenburg, Katja T C A
• Format: Dataset
• Language: English
• Published: PANGAEA - Data Publisher for Earth & Environmental Science 2021
• Subjects: Animalia; Calcification/Dissolution; Coast and continental shelf; Field observation; Growth/Morphology; Limacina helicina; Mollusca; North Pacific; Pelagos; Single species; Temperate; Upwelling; Zooplankton; Type; Species; Registration number of species; Uniform resource locator/link to reference; Station label; LATITUDE; LONGITUDE; Identification; Location; Shell, number of whorls; Diameter; Height; Shell thickness; Dissolution; Shell surface area; Salinity; Temperature, water; Carbon, inorganic, dissolved; Alkalinity, total; Silicate; Phosphate; Carbonate system computation flag; pH; Carbon dioxide; Fugacity of carbon dioxide water at sea surface temperature wet air; Partial pressure of carbon dioxide water at sea surface temperature wet air; Bicarbonate ion; Carbonate ion; Aragonite saturation state; Calcite saturation state; Calculated using seacarb after Nisumaa et al. 2010; Ocean Acidification International Coordination Centre OA-ICC; Pacific; Ocean acidification
• Online Access: https://dx.doi.org/10.1594/pangaea.930065; https://doi.pangaea.de/10.1594/PANGAEA.930065

Shelled pteropods are widely regarded as bioindicators for ocean acidification, because their fragile aragonite shells are susceptible to increasing ocean acidity. While short-term incubations have demonstrated that pteropod calcification is negatively impacted by ocean acidification, we know little about net calcification in response to varying ocean conditions in natural populations. Here, we examine in situ calcification of Limacina helicina pteropods collected from the California Current Ecosystem, a coastal upwelling system with strong spatial gradients in ocean carbonate chemistry, dissolved oxygen and temperature. Depth-averaged pH ranged from 8.03 in warmer offshore waters to 7.77 in cold CO2-rich waters nearshore. Based on high-resolution micro-CT technology, we showed that shell thickness declined by 37% along the upwelling gradient from offshore to nearshore water. Dissolution marks covered only 2% of the shell surface area and were not associated with the observed variation in shell thickness. We thus infer that pteropods make thinner shells where upwelling brings more acidified and colder waters to the surface. Probably the thinner shells do not result from enhanced dissolution, but are due to a decline in calcification. Reduced calcification of pteropods is likely to have major ecological and biogeochemical implications for the cycling of calcium carbonate in the oceans. : In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2021) 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 by seacarb is 2021-04-07.