Revising the consensus on the effect of ocean acidification on coral calcification

2024

Diplôme

Rodolfo-Metalpa Riccardo

Nouméa : Université de la Nouvelle-Calédonie, 2024, 129 p. multigr.

Mém. HDR.Habilitation à Diriger des Recherches : Sciences du Vivant - Biol. cellulaire, 2024/02/20.

Ocean acidification (OA) is one of the main threats to marine habitats likely causing changes in biodiversity and ecosystem function within this century. Ocean acidification might affect various physiological parameters at different stages of the animal life history, from their reproduction, through larval phases and adult growth. Calcifying species, such as scleractinian corals which harbour a large part of the world`s ocean biodiversity, apparently will be the most affected by OA since their calcification and dissolution rates seem related to seawater carbonate chemistry. Studies show a decline in the net calcification rates as a result of decreasing pH and carbonate ions concentration, and an increase in the dissolution rate of carbonate skeletons. However, the consensus on the projected hindering of species calcification ability is in contradiction with several past and recent findings showing that some calcifiers do not seem to be affected by OA. These divergent results have clearly shown that our actual knowledge of biological response to OA is extremely limited and that some assumptions we have used so far might be inaccurate to predict species response to OA. In this report, the consensus of the response of coral calcification rates to acidification, early erroneous assumptions and misconceptions will be revised in the light of recent milestone contributions which impose an adjustment of our current understanding on coral calcification responses face to OA.

Climatologie / Météorologie [032CLIMET] ; Autres invertébrés [034BIOINV05]

Fonds IRD [F A010092406]

fdi:010092406