First mesocosm experiments to study the impacts of ocean acidification on plankton communities in the NW Mediterranean Sea (MedSeA project)

• Published in: Estuarine, Coastal and Shelf Science
• Main Authors: Gazeau, F, Sallon, A, Maugendre, L, Louis, J, Dellisanti, W, Gaubert, M, Lejeune, P, Gobert, Sylvie, Borges, Alberto, Harlay, J, Champenois, Willy, Alliouane, S, Taillandier, Louis, F, Obolensky, G, Grisoni, JM, Gieu, C
• Other Authors: STARESO, FOCUS - Freshwater and OCeanic science Unit of reSearch - ULiège
• Format: Article in Journal/Newspaper
• Language: English
• Published: Academic Press 2016
• Subjects: Ocean acidification; Mediterranean Sea; Pelagic mesocosm; Plankton community; Oligotrophic area; Life sciences; Environmental sciences & ecology; Aquatic sciences & oceanology; Sciences du vivant; Sciences de l’environnement & écologie; Sciences aquatiques & océanologie
• Online Access: https://orbi.uliege.be/handle/2268/197834; https://orbi.uliege.be/bitstream/2268/197834/1/Gazeau%20et%20al.%20%282016%29.pdf; https://doi.org/10.1016/j.ecss.2016.05.014

peer reviewed There is a growing international interest in studying the effects of ocean acidification on plankton communities that play a major role in the global carbon cycle and in the consumption of atmospheric CO2 via the so-called biological pump. Recently, several mesocosm experiments reported on the effect of ocean acidification on marine plankton communities, although the majority were performed in eutro- phic conditions or following nutrient addition. The objective of the present study was to perform two mesocosm experiments in the oligo- to meso-trophic Northwestern Mediterranean Sea during two seasons with contrasting environmental conditions: in summer 2012 in the Bay of Calvi (Corsica, France) and in winter 2013 in the Bay of Villefranche (France). This paper describes the objectives of these ex- periments, the study sites, the experimental set-up and the environmental and experimental conditions during the two experiments. The 20-day experiment in the Bay of Calvi was undoubtedly representative of summer conditions in the Northwestern Mediterranean Sea with low nutrient and chlorophyll a concentrations, warm waters and high surface solar irradiance. In contrast, the winter experiment, which was reduced to 12 days because of bad weather conditions, failed to reproduce the mesotrophic con- ditions typical of the wintertime in this area. Indeed, a rapid increase in phytoplankton biomass during the acidification phase led to a strong decrease in nitrate concentrations and an unrealistic N and P co- limitation at this period of the year. An overview of the 11 other papers related to this study and pub- lished in this special issue is provided. MEDiterranean Sea Acidification in a changing climate eFOCE