Calcification Responses to Mid- and End-Century Ocean Acidification Levels in the Stony Coral, Astrangia poculata

• Main Authors: Sheffey, Heather L., Barshis, Daniel J., Tansik, Anna L.
• Format: Audio
• Language: unknown
• Published: ODU Digital Commons 2020
• Subjects: Biology; Ecology and Evolutionary Biology; Marine Biology; Ocean acidification
• Online Access: https://digitalcommons.odu.edu/undergradsymposium/2020/sciences/6

Climate change stressors are becoming a growing concern with the rampant release of CO2 in the atmosphere. The impact of extreme CO2 concentrations on stony coral health is well researched, but it is necessary to develop research at more realistic CO2 ppm values. Following RCP 6.0, laid out by the Intergovernmental Panel on Climate Change, we exposed three groups of the Northern Star Coral Astrangia poculata to 410 ppm, 500 ppm, and 800 ppm CO2 for several months. The intention is to mimic present day, mid-century, and end-century OA levels, respectively, for several months in order to understand long term impacts on calcification. We also investigated the role of symbionts in resistance to OA by taking advantage of the facultative nature of Astrangia poculata. Calcification rates will be determined by using the Alkalinity Anomaly method under light and dark conditions for both symbiotic and asymbiotic corals during the experiment. This will allow us to understand the role of the algal symbiont in the coral’s success in acidified waters as the extent to which stony coral calcification will be impacted by OA can be greatly impacted by the concentration of algal symbionts. Corals subjected to higher levels of CO2 displayed lower rates of calcification compared to present day conditions after only one month.