Seawater carbonate chemistry and shell microstructure, mechanical properties of an edible estuarine oyster

• Main Authors: Meng, Yuan, Guo, Zhenbin, Yao, Haimin, Yeung, Kelvin W K, Thiyagarajan, Vengatesen
• Format: Dataset
• Language: English
• Published: PANGAEA 2019
• Subjects: Alkalinity; total; standard deviation; Animalia; Aragonite saturation state; Area porosity; Benthic animals; Benthos; Bicarbonate ion; Bottles or small containers/Aquaria (<20 L); Brackish waters; Calcite saturation state; Calculated using CO2SYS; Calculated using seacarb after Nisumaa et al. (2010); Carbon; inorganic; dissolved; Carbonate ion; Carbonate system computation flag; Carbon dioxide; Density; EXP; Experiment; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Growth/Morphology; Hardness; Laboratory experiment; Magallana hongkongensis; Mollusca; North Pacific; OA-ICC; Ocean Acidification International Coordination Centre; Other studied parameter or process; Partial pressure of carbon dioxide; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); pH; Potentiometric; Potentiometric titration; Registration number of species; Ocean acidification
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.908459; https://doi.org/10.1594/PANGAEA.908459

Ocean acidification (OA) is well-known for impairing marine calcification; however, the end response of several essential species to this perturbation remains unknown. Decreased pH and saturation levels (Omega) of minerals under OA is projected to alter shell crystallography and thus to reduce shell mechanical properties. This study examined this hypothesis using a commercially important estuarine oyster Magallana hongkongensis. Although shell damage occurred on the outmost prismatic layer and the undying myostracum at decreased pH 7.6 and 7.3, the major foliated layer was relatively unharmed. Oysters maintained their shell hardness and stiffness through altered crystal unit orientation under pH 7.6 conditions. However, under the undersaturated conditions (Omega Cal ~ 0.8) at pH 7.3, the realigned crystal units in foliated layer ultimately resulted in less stiff shells which indicated although estuarine oysters are mechanically resistant to unfavorable calcification conditions, extremely low pH condition is still a threat to this essential species.