Coral calcification mechanisms facilitate adaptive responses to ocean acidification

Verena Schoepf, Christopher P. Jury, Robert J. Toonen, Malcolm T. McCulloch

Research output: Contribution to journalArticlepeer-review

47 Citations (Web of Science)

Abstract

Ocean acidification (OA) is a pressing threat to reef-building corals, but it remains poorly understood how coral calcification is inhibited by OA and whether corals could acclimatize and/or adapt toOA. Using a novel geochemical approach, we reconstructed the carbonate chemistry of the calcifying fluid in two coral species using both a pH and dissolved inorganic carbon (DIC) proxy (delta B-11 and B/Ca, respectively). To address the potential for adaptive responses, both species were collected from two sites spanning a natural gradient in seawater pH and temperature, and then subjected to three pHT levels (8.04, 7.88, 7.71) crossed by two temperatures (control, -1.5 degrees C) for 14 weeks. Corals from the site with naturally lower seawater pH calcified faster and maintained growth better under simulated OA than corals from the higher-pH site. This ability was consistently linked to higher pH yet lower DIC values in the calcifying fluid, suggesting that these differences are the result of long-termacclimatization and/or local adaptation to naturally lower seawater pH. Nevertheless, all corals elevated both pH and DIC significantly over seawater values, even under OA. This implies that high pH upregulation combined with moderate levels of DIC upregulation promote resistance and adaptive responses of coral calcification to OA.

Original languageEnglish
Article number20172117
Number of pages9
JournalProceedings of the Royal Society of London: series B
Volume284
Issue number1868
DOIs
Publication statusPublished - 6 Dec 2017

Fingerprint

Dive into the research topics of 'Coral calcification mechanisms facilitate adaptive responses to ocean acidification'. Together they form a unique fingerprint.

Cite this