Seawater carbonate chemistry and photosynthetic physiology and inorganic carbon processing of the temperate coral Oculina arbuscula

• Main Authors: Wang, C, Arneson, Erin M, Gleason, Daniel F, Hopkinson, Brian M
• Format: Dataset
• Language: English
• Published: PANGAEA 2021
• Subjects: Alkalinity; total; Animalia; Aragonite saturation state; Benthic animals; Benthos; Bicarbonate ion; Calcite saturation state; Calculated using seacarb after Nisumaa et al. (2010); Carbon; inorganic; dissolved; Carbonate ion; Carbonate system computation flag; Carbon dioxide; Chlorophyll a per cell; Chlorophyll c per cell; Cnidaria; Coast and continental shelf; Containers and aquaria (20-1000 L or < 1 m**2); Coral fragments; EXP; Experiment; Experiment duration; Extracellular carbonic anhydrase activity; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Growth/Morphology; Growth rate per area; Identification; Intracellular carbonic anhydrase activity; J_Y_Reef; Laboratory experiment; Light saturated maximum photosynthetic rate; Light saturation; Maximum quantum yield of photosystem II; North Atlantic; OA-ICC; Ocean Acidification International Coordination Centre; Oculina arbuscula; Other metabolic rates; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); Peridinin per cell; pH; Primary production/Photosynthesis; Ratio; Registration number of species; Respiration; Respiration rate; oxygen; Salinity; Ocean acidification
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.931943; https://doi.org/10.1594/PANGAEA.931943

Both juvenile and adult life stages of the temperate scleractinian coral Oculina arbuscula are resilient to the effects of moderate ocean acidification (OA) in contrast to many tropical corals in which growth and calcification rates are suppressed. Here, potential mechanisms of resilience to OA related to photosynthetic physiology and inorganic carbon processing were studied in adult O. arbuscula colonies. After exposing colonies to ambient and elevated carbon dioxide (CO2) treatments for 7 weeks, photosynthetic performance was characterized using photosynthesis versus irradiance experiments, chlorophyll fluorescence kinetics, and algal pigment content. Inorganic carbon-processing capabilities were assessed by measurement of internal and external carbonic anhydrase activity of the coral host, internal carbonic anhydrase activity of symbiotic algae, and the reliance of photosynthesis on external carbonic anhydrase. Photosynthetic physiology was unaffected by OA ruling out the possibility that resilience was mediated by increased photosynthetic energy supply. Carbonic anhydrase activities were maintained at elevated CO2 suggesting no major rearrangements of the inorganic carbon-processing machinery, but this could be a sign of resilience since tropical corals often down-regulate carbonic anhydrases at high CO2. The general lack of effect of ocean acidification on these physiological traits suggests other characteristics, such as maintenance of calcifying fluid pH and ability to acquire energy from heterotrophy, may be more important for the resilience of O. arbuscula to OA.