[A-CG41] Coastal Ecosystems 2. Coral reefs, seagrass and macroalgal beds, and mangroves

[ACG41-01] Using natural analogues for the study of ecosystems effects of Ocean Acidification: the Shikine CO₂ seep and the ICONA network

★Invited Papers

*Agostini Sylvain¹, Ben Harvey¹, Lucia Porzio¹, Jason Hall-Spencer^2,1, Carlo Cattano³, Fanny Houlbreque⁴, Timothy Ravasi⁵, Haruko Kurihara⁷, Bayden Russel⁶, James Reimer⁷, ICONA participants⁸, Marco Milazzo⁹, Riccardo Rodolfo-Metalpa⁴, Shigeki Wada¹ (1.Shimoda Marine Research Center, University of Tsukuba, Japan, 2.University of Plymouth, UK, 3.Stazione Zoologica Anton Dohrn, Italy, 4.UMR Entropie, New Caledonia, 5.Okinawa Institute of Science and Technology, 6.Swire Institute of Marine Science, University of Hong Kong, Hong Kong, 7.University of the Ryukyus, Japan, 8.ICONA network, 9.University of Palermo)

Keywords:ocean acidification, natural analogues, coral reefs

Increasing atmospheric CO₂ concentration is driving the rapid acidification of the ocean. This will certainly lead to severe consequences to the marine environment. Although laboratory experiments show that future CO₂ and temperature levels can affect a variety of physiological and behavioral traits and processes of coral reef organisms, the ecosystem effects remain uncertain and with considerable variation among species. The Shikine CO₂ seep was described in 2015 and shown to be suitable for the study of ocean acidification. Since then more than 20 papers have been published, showing a wide range of physiological and ecological effects of ocean acidification. Here we will focus on the effects on scleractinian corals. By studying the resistant species and individuals found in the high CO₂ areas, we hope to understand the eco-physiological traits and adaptation mechanisms that will shape future coral communities around the world.

Natural analogues of a high CO₂ world such as volcanic CO₂ vents, like in Shikine Island, and enclosed bays provide a unique opportunity to investigate the fundamental responses and potential adaptation of marine organisms to long-term exposure to elevated CO₂, temperature, salinity and hypoxia. The International CO₂ Natural Analogues (ICONA) network was created to foster the use of natural analogues, harmonize the techniques employed and enhance exchanges and collaboration. The network is now working closely with OARS, a UN ocean decade program.