Seawater carbonate chemistry and Mg/Ca ratios of laboratory-grown neogloboquadrina foraminifera, supplement to: Davis, Catherine V; Fehrenbacher, Jennifer; Hill, Tessa M; Russell, Ann D; Spero, Howard J (2017): Relationships Between Temperature, pH, and Crusting on Mg/Ca Ratios in Laboratory-Grown Neogloboquadrina Foraminifera. Paleoceanography, 32(11), 1137-1152

• Main Authors: Davis, Catherine V, Fehrenbacher, Jennifer, Hill, Tessa M, Russell, Ann D, Spero, Howard J
• Format: Dataset
• Language: English
• Published: PANGAEA - Data Publisher for Earth & Environmental Science 2017
• Subjects: Biomass/Abundance/Elemental composition; Bottles or small containers/Aquaria <20 L; Chromista; Foraminifera; Growth/Morphology; Heterotrophic prokaryotes; Laboratory experiment; Neogloboquadrina incompta; Neogloboquadrina pachyderma; North Pacific; Open ocean; Other; Pelagos; Single species; Temperate; Temperature; Type; Species; Registration number of species; Uniform resource locator/link to reference; Temperature, water; pH; Carbonate ion; Alkalinity, total; Magnesium/Calcium ratio; Description; Shell dimension; Salinity; Salinity, standard deviation; Carbonate system computation flag; 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; Carbon, inorganic, dissolved; Aragonite saturation state; Calcite saturation state; Experiment; Calculated using seacarb after Nisumaa et al. 2010; Ocean Acidification International Coordination Centre OA-ICC; Bering Sea; Pacific; Ocean acidification
• Online Access: https://dx.doi.org/10.1594/pangaea.892335; https://doi.pangaea.de/10.1594/PANGAEA.892335

Mg/Ca ratio paleothermometry in foraminifera is an important tool for the reconstruction and interpretation of past environments. However, existing Mg/Ca:temperature relationships for planktic species inhabiting mid- and high- latitude environments are limited by a lack of information about the development and impact of low-Mg/Ca ratio “crusts” and the influence of the carbonate system on Mg/Ca ratios in these groups. To address this, we cultured individual specimens of Neogloboquadrina incompta and Neogloboquadrina pachyderma in seawater across a range of temperature (6 °- 12 °C) and pH (7.4 – 8.2). We found by laser ablation inductively couple mass spectrometry analyses of shells that culture-grown crust calcite in N. incompta had a lower Mg/Ca ratio than ontogenetic calcite formed at the same temperature, suggesting that temperature is not responsible for the low Mg/Ca ratio of neogloboquadrinid crusts. The Mg/Ca:temperature relationship for ontogenetic calcite in N. incompta was consistent with the previously published culture-based relationship and no significant relationship was found between Mg/Ca ratios and pH in this species. However, the Mg/Ca ratio in laboratory cultured N. pachyderma was much higher than that reported in previous core-top and sediment trap samples, due to lack of crust formation in culture. Application of our ontogenetic calcite-specific Mg/Ca:temperature relationships to fossil N. pachyderma and N. incompta from five intervals in cores from the Santa Barbara Basin and the Bering Sea show that excluding crust calcite in fossil specimens may improve Mg/Ca-based temperature estimates. : In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2016) 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 2018-07-02.