Projet EPOCA : colloque de fin du 1er projet international de recherche scientifique sur l’acidification des océans (in French)

Du 02 au 05 avril a eu lieu à St Jean Cap Ferrat le Colloque de fin du premier projet international de recherche scientifique EPOCA sur l’acidification des océans “, projet coordonné par Jean-Pierre Gattuso, Dierceteur de recherche CNRS à l’Observatoire Océanologique de Villefranche sur Mer (LOV – OOV/CNRS/UPMC). Cette réunion marque donc la fin de ce projet de recherche international qui étudie les conséquences de nos émissions de CO2 sur des organismes et écosystèmes marins par plus de 100 chercheurs de dix pays européens.

En croissance exponentielle, les émissions de gaz carbonique (CO2) dues aux activités humaines ont un effet notoire sur le climat. Moins connue, leur absorption par l’océan entraîne une inexorable acidification de l’eau de mer. Mais quel est l’impact de ce phénomène sur les organismes et les écosystèmes marins ? Le projet européen EPOCA, lancé en mai 2008, a visé à mieux comprendre l’acidification des océans, à étudier ses conséquences sur la biologie marine, les prédire pour le siècle à venir et émettre des recommandations vers les décisionnaires politiques.

Coordonné par Jean-Pierre Gattuso, chercheur CNRS au Laboratoire d’Océanographie de Villefranche-sur-mer (LOV), le programme a réuni 32 partenaires répartis sur 10 pays européens (Allemagne, Belgique, France, Grande Bretagne, Islande, Italie, Norvège, Pays-Bas, Suède et Suisse). Le programme a bénéficié d’un budget de 16,5 millions d’euros sur 4 ans, dont 6,5 millions d’euros financés par l’Union européenne.

Les chercheurs d’EPOCA ont publié plus de 150 articles pendant la durée du projet.

Scientists to study risks of ocean acidification to Scotland’s corals

With the oceans warming and moving towards acidity, will Scotland’s cold-water corals die out within a hundred years, as some predict, or do they have the capacity to adapt and survive?

These are the key questions facing a team of international scientists about to set off on a month-long research voyage in the waters around Scotland using the latest robotic submersible technology. The researchers will be aboard the Natural Environment Research Council’s Royal Research Ship James Cook.

The ‘Changing Oceans’ expedition is part of the £12m UK Ocean Acidification (UKOA) research programme jointly funded by NERC, the Department of Energy & Climate Change (DECC) and the Department for Environment, Fisheries & Rural Affairs (Defra).

Fish might become “fearless” as a result of ocean acidification

The rising level of atmospheric CO2 has led to several studies focussing on changes in terrestrial and water ecosystems that might occur as a consequence. Ocean acidification, which is caused mainly by the increasing amount of CO2 dissolved in sea water, is at the forefront of marine research topics. However, most of the studies focus on calcifying organisms (e.g. corals, crustaceans) and only a few looked at fish and changes in fish behaviour so far.

A recently published paper in Functional Ecology, a British Ecological Society journal, is aiming to fill in a knowledge gap by examining the links between ocean acidification and changes to coral reef fish behaviour based on visual effects. Behavioural studies have demonstrated already that elevated CO2 levels can cause chemosensory and auditory impairment.

Seabed test mimics carbon dioxide release

Scientists are beginning a month-long experiment in Scottish waters to study the impact of a possible leak from an undersea carbon dioxide storage site.

Working in Ardmucknish Bay near Oban, researchers will allow CO2 to bubble through sediments from a buried pipe and look for impacts on marine life.

Capturing CO2 from power stations and burying it under the seabed is viewed as an important global warming fix.

Impact of ocean acidification on Mediterranean coralline algae

Coralline algae are a major calcifying component of most Mediterranean benthic coastal ecosystems. They are of particular ecological importance, inducing settlement and recruitment of numerous invertebrates and providing habitats for a high diversity of associated organisms. They are also of significant importance in the carbon and carbonate cycles of shallow coastal ecosystems, being major contributors to CO₂ fluxes through high community CaCO₃ production and dissolution. However, coralline algae are among the calcifying organisms that appear to be the most sensitive to ocean acidification due to the solubility of their high magnesium calcite skeletons. We investigated the effects of ocean acidification on coralline algae both through in situ observations in a volcanic CO₂ vent area off Ischia (Italy) and through a long-term (one-year) mesocosm experiment combining the effects of elevated pCO₂ (lowered pH) and elevated temperature.