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Ocean acidification poses a threat to coral skeleton formation via reductions in the saturation state of aragonite (ΩAr) in seawater. Given that corals precipitate their skeletons from a calcifying fluid supplied by seawater, reductions in seawater ΩArshould, in theory, confound calcification. Here, we reconstruct up to 200 years of coral calcifying fluid ΩAr, using Raman spectroscopy techniques, at approximately monthly resolution in twoPoritessp. skeletal cores from the Coral Sea region to investigate (i) the regulation of coral calcifying fluid ΩArand (ii) the skeletal calcification response to industrial-era ocean acidification. Our results reveal a significant increase in calcifying fluid ΩAr, suggesting that some corals may adjust to the pace of acidification in the wild more effectively than suggested by short-term laboratory studies.
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Coral growth persistence amidst bleaching events
Abstract As mass bleaching events decimate stony coral populations, production of calcium carbonate is diminished on reefs, dampening their capacity to keep pace with rising sea levels. However, perturbations to the calcification process of surviving wild corals during bleaching are poorly constrained, owing to the lack of suitable techniques to retroactively extract this information from coral skeletons at sufficient resolution. Here, we use novel Raman spectrometry techniques to test the biogeochemical response of long‐lived corals before, during, and after bleaching. Maintenance of high aragonite saturation state (Ω Ar ) in the coral calcifying fluid is key to driving rapid skeletal growth but would be expected to decrease when corals become energetically depleted without their symbionts. Contrary to this expectation, our results demonstrate that corals upregulate calcifying fluid Ω Ar during bleaching and for at least 2 yr after recovery. This indicates that the calcification process of coral‐bleaching survivors is unexpectedly resilient.
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- Award ID(s):
- 2117987
- PAR ID:
- 10465256
- Date Published:
- Journal Name:
- Limnology and Oceanography Letters
- Volume:
- 8
- Issue:
- 5
- ISSN:
- 2378-2242
- Page Range / eLocation ID:
- 734 to 741
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1002/lol2.10340
