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Massive Corals Can Adapt to End-of-Century CO2 Concentrations

Paper Reviewed
Wall, M., Fietzke, J., Schmidt, G.M., Fink, A., Hofmann, L.C., de Beer, D. and Fabricius K.E. 2016. Internal pH regulation facilitates in situ long-term acclimation of massive corals to end-of-century carbon dioxide conditions. Scientific Reports 6: 10.1038/srep30688.

Noting that "the resilience of tropical corals to ocean acidification depends on their ability to regulate the pH within their calcifying fluid (pHcf)," Wall et al. (2016) write that "it is still unclear if pHcf homeostasis can be maintained throughout a coral's lifetime." So to find out for themselves about the matter, the seven scientists studied a natural analogue of ocean acidification in volcanic carbon dioxide seeps of the Milne Bay Province of Papua New Guinea, where massive Porites corals have grown for decades along a natural seawater pH gradient ranging from pH 8.1 to 7.4. And what did they learn by so doing?

Wall et al. report that their study showed that massive Porites corals "will be able to persist in the oceans of 2100, due to observed similar growth rates to those of present day conditions [see Fabricius et al. (2011)]," along with enhanced photosynthesis [see Strahl et al., 2015] and their ability to maintain a high internal pHcf, all of which factors contribute to the current dominance of Porites' corals at Papua New Guinea CO2 seeps.

Fabricius, K.E. et al. 2011. Losers and winners in coral reefs acclimatized to elevated carbon dioxide concentrations. Nature Climate Change 1: 165-169.

Strahl, J. et al. 2015. Physiological and ecological performance differs in four coral taxa at a volcanic carbon dioxide seep. Comp. Biochem. Physiolo. Part A Mol. Integr. Physiol. 184: 179-186.

Posted 6 December 2016