The Impact of Heterotrophy in the Resilience of the Temperate Coral Oculina arbuscula to Ocean Acidification
Faculty Mentor
Daniel Gleason
Location
Russell Union 2080
Type of Research
Completed
Session Format
Poster Presentation
College
Jack Averitt College of Graduate Studies
Department
School of Earth, Environment, and Sustainability
Abstract
Excess CO2 absorbed by the oceans decreases seawater pH and can negatively impact coral calcification rates. Oculina arbuscula is a facultatively symbiotic temperate coral that exhibits resilience to ocean acidification (OA) regardless of whether colonies are in a symbiotic or aposymbiotic state. To investigate the hypothesis that enhanced heterotrophy contributes to the ability of O. arbuscula to ameliorate the negative effects of OA, a 90-day laboratory experiment was conducted exposing aposymbiotic O. arbuscula fragments to a pH of either 7.8 or 8.1 under three different feeding levels. Fragments with higher food consumption showed significantly higher calcification rates (p< 0.001), but no significant effect of pH on calcification was detected. Biochemical analyses indicated total protein stores increased with higher food consumption (p< 0.001) but were unaffected by pH exposure. Carbohydrate stores were reduced by both low food consumption (p=0.012) and low pH exposure (p=0.026), with no significant interaction detected. These results suggest that the energy provided by enhanced heterotrophy allows Oculina arbuscula to sustain calcification rates but may not be the mechanism underlying their resilience to OA.
Program Description
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Start Date
4-23-2026 11:45 AM
End Date
4-23-2026 12:00 PM
Recommended Citation
Daniel, Alejandra E., "The Impact of Heterotrophy in the Resilience of the Temperate Coral Oculina arbuscula to Ocean Acidification" (2026). GS4 Student Scholars Symposium. 128.
https://digitalcommons.georgiasouthern.edu/research_symposium/2026/2026/128
The Impact of Heterotrophy in the Resilience of the Temperate Coral Oculina arbuscula to Ocean Acidification
Russell Union 2080
Excess CO2 absorbed by the oceans decreases seawater pH and can negatively impact coral calcification rates. Oculina arbuscula is a facultatively symbiotic temperate coral that exhibits resilience to ocean acidification (OA) regardless of whether colonies are in a symbiotic or aposymbiotic state. To investigate the hypothesis that enhanced heterotrophy contributes to the ability of O. arbuscula to ameliorate the negative effects of OA, a 90-day laboratory experiment was conducted exposing aposymbiotic O. arbuscula fragments to a pH of either 7.8 or 8.1 under three different feeding levels. Fragments with higher food consumption showed significantly higher calcification rates (p< 0.001), but no significant effect of pH on calcification was detected. Biochemical analyses indicated total protein stores increased with higher food consumption (p< 0.001) but were unaffected by pH exposure. Carbohydrate stores were reduced by both low food consumption (p=0.012) and low pH exposure (p=0.026), with no significant interaction detected. These results suggest that the energy provided by enhanced heterotrophy allows Oculina arbuscula to sustain calcification rates but may not be the mechanism underlying their resilience to OA.
