Seawater carbonate chemistry and photochemical efficiency and symbiont density of reef coral Pocillopora damicornis

• Main Authors: Jiang, Lei, Sun, You-Fan, Zhang, Yuyang, Tian, Yuan, Lei, Xinming, Zhou, Guowei, Yuan, Tao, Yuan, Xiangcheng, Liu, S, Huang, Hui
• Format: Dataset
• Language: English
• Published: PANGAEA 2022
• Subjects: Alkalinity; total; standard deviation; Animalia; Aragonite saturation state; Bicarbonate ion; Bottles or small containers/Aquaria (<20 L); 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; Cnidaria; Coast and continental shelf; EXP; Experiment; Experiment duration; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Gross photosynthesis rate; oxygen; per individual; Laboratory experiment; Luhuitou_fringing_reef; Malondialdehyde; per protein mass; Mortality/Survival; Net photosynthesis rate; 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); Pelagos; pH; Photochemical efficiency; Pocillopora damicornis; Ocean acidification
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.941570; https://doi.org/10.1594/PANGAEA.941570

Establishing the thermal reaction norm of coral larvae under elevated pCO2 is crucial to anticipate how larval dispersal and population maintenance may be affected by future climate change. Here, we characterized the functional relationship between temperature (27−33 °C) and larval performance of the reef coral Pocillopora damicornis under two pCO2 levels. The results showed that the temperature threshold of larvae was between 32 and 33 °C, as evidenced by the abrupt declines in photochemical efficiency and symbiont density, whereas no oxidative damage was observed between 27 and 33 °C and elevated pCO2 did not influence any of these parameters. In addition, larval respiration and photosynthesis rates exhibited parabolic responses to temperature, and this relationship conformed to the Gaussian–Gompertz model with an optimal temperature around 31.5 °C, which was approximately 2.5 °C above the summer mean temperature, suggesting the potential for thermal acclimation. Most importantly, elevated pCO2 significantly enhanced the larval photosynthesis and the stimulatory effect of elevated pCO2 on the photosynthetic rates and capacity was more pronounced in cool and warm temperatures, indicative of shifted thermal sensitivity under high pCO2. These results suggest that ocean acidification could alter the thermal performance curves and tolerance window of brooded P. damicornis larvae, with profound and important implications for larval ecology in a future changing ocean.