Seawater carbonate chemistry and calcification rate, calcifying fluid pH, calcifying fluid DIC, photosynthetic rates, metabolic alteration of pH in the DBL of corals and coralline algae

• Main Authors: Comeau, Steeve, Cornwall, Christopher Edward, Pupier, C A, DeCarlo, Thomas M, Alessi, Cinzia, Trehern, R, McCulloch, Malcolm T
• Format: Dataset
• Language: English
• Published: PANGAEA - Data Publisher for Earth & Environmental Science 2019
• Subjects: Acid-base regulation; Acropora yongei; Animalia; Benthic animals; Benthos; Biomass/Abundance/Elemental composition; Calcification/Dissolution; Cnidaria; Coast and continental shelf; Containers and aquaria 20-1000 L or < 1 m**2; Indian Ocean; Laboratory experiment; Light; Macroalgae; Other; Plantae; Plesiastrea versipora; Primary production/Photosynthesis; Respiration; Rhodophyta; Single species; Sporolithon durum; Temperate; Type; Species; Registration number of species; Uniform resource locator/link to reference; Identification; Treatment; pH; Name; δ11B; Boron/Calcium ratio; Calcifying fluid, pH; Calcifying fluid, dissolved inorganic carbon; Calcifying fluid, aragonite saturation state; Calcification rate of calcium carbonate; Calcifying fluid, carbonate ion; Full width at half maximum; Magnesium-Calcite; Net photosynthesis rate, oxygen; Respiration rate, oxygen; Maximal differences in pH; pH, standard deviation; Alkalinity, total; Alkalinity, total, standard deviation; Partial pressure of carbon dioxide water at sea surface temperature wet air; Partial pressure of carbon dioxide, standard deviation; Temperature, water; Temperature, water, standard deviation; Salinity; Carbonate system computation flag; Carbon dioxide; Carbon dioxide, standard deviation; Fugacity of carbon dioxide water at sea surface temperature wet air; Fugacity of carbon dioxide in seawater, standard deviation; Bicarbonate ion; Bicarbonate ion, standard deviation; Carbonate ion; Carbonate ion, standard deviation; Carbon, inorganic, dissolved; Carbon, inorganic, dissolved, standard deviation; Aragonite saturation state; Aragonite saturation state, standard deviation; Calcite saturation state; Calcite saturation state, standard deviation; Experiment; Raman microscopy; Potentiometric; Potentiometric titration; Calculated using seacarb; Calculated using seacarb after Nisumaa et al. 2010; Calculated using seacarb after Orr et al. 2018; Ocean Acidification International Coordination Centre OA-ICC; Indian; Ocean acidification
• Online Access: https://dx.doi.org/10.1594/pangaea.914328; https://doi.pangaea.de/10.1594/PANGAEA.914328

Natural variability in pH in the diffusive boundary layer (DBL), the discrete layer of seawater between bulk seawater and the outer surface of organisms, could be an important factor determining the response of corals and coralline algae to ocean acidification (OA). Here, two corals with different morphologies and one coralline alga were maintained under two different regimes of flow velocities, pH, and light intensities in a 12 flumes experimental system for a period of 27 weeks. We used a combination of geochemical proxies, physiological and micro-probe measurements to assess how these treatments affected the conditions in the DBL and the response of organisms to OA. Overall, low flow velocity did not ameliorate the negative effect of low pH and therefore did not provide a refugia from OA. Flow velocity had species-specific effects with positive effects on calcification for two species. pH in the calcifying fluid (pHcf) was reduced by low flow in both corals at low light only. pHcf was significantly impacted by pH in the DBL for the two species capable of significantly modifying pH in the DBL. The dissolved inorganic carbon in the calcifying fluid (DICcf) was highest under low pH for the corals and low flow for the coralline, while the saturation state in the calcifying fluid and its proxy (FWHM) were generally not affected by the treatments. This study therefore demonstrates that the effects of OA will manifest most severely in a combination of lower light and lower flow habitats for sub-tropical coralline algae. These effects will also be greatest in lower flow habitats for some corals. Together with existing literature, these findings reinforce that the effects of OA are highly context dependent, and will differ greatly between habitats, and depending on species composition. : In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2019) 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 2020-03-18.