Ventura P. auteur aut IRD Jarrold M. D. auteur aut IRD Merle P. L. auteur aut IRD Barnay-Verdier S. auteur aut IRD Zamoum T. auteur aut IRD Rodolfo-Metalpa Riccardo auteur aut IRD Calosi P. auteur aut IRD Furla P. auteur aut IRD text journalArticle eng text/pdf born digital access Non-calcifying photosynthetic anthozoans have emerged as a group that may thrive under high carbon dioxide partial pressure (pCO(2)) conditions via increased productivity. However, the physiological mechanisms underlying this potential success are unclear. Here we investigated the impact of high pCO(2) on the dissolved inorganic carbon (DIC) use in the temperate sea anemone Anemonia viridis. We assessed the impacts of long-term exposure to high pCO(2), i.e. sampling in situ natural CO2 vents (Vulcano, Italy), and short-term exposure, i.e. during a 3 wk controlled laboratory experiment. We focused on photo-physiological parameters (net photosynthesis rates, chlorophyll a content and Symbiodinium density) and on carbonic anhydrase (CA) activity, an enzyme involved in the energy-demanding process of DIC absorption. Long-term exposure to high pCO(2) had no impact on Symbiodinium density and chlorophyll a content. In contrst, short-term exposure to high pCO(2) induced a significant reduction in Symbiodinium density, which together with unchanged net photosynthesis resulted in the increase of Symbiodinium productivity per cell. Finally, in both in situ long-term and laboratory short-term exposure to high pCO(2), we observed a significant decrease in the CA activity of sea anemones, suggesting a change in DIC use (i.e. from an HCO3- to a CO2 user). This change could enable a shift in the energy budget that may increase the ability of non-calcifying photosynthetic anthozoans to cope with ocean acidification. specialized Dissolved inorganic carbon uptake Carbonic anhydrase Ocean acidification Plasticity CO2 vent Anemonia viridis ITALIE SICILE 036 032 559 257-263 2016 0171-8630 https://www.documentation.ird.fr/hor/fdi:010068689 10.3354/meps11916 0171-8630 [F B010068689] https://www.documentation.ird.fr/hor/fdi:010068689 https://www.documentation.ird.fr/intranet/publi/2016/12/010068689.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2017-01-09 2017-08-23 fdi:010068689 fre