Cotovicz L. C. auteur aut IRD Knoppers B. A. auteur aut IRD Brandini N. auteur aut IRD Poirier D. auteur aut IRD Santos S. J. C. auteur aut IRD Abril Gwenaël auteur aut IRD text journalArticle eng text/pdf born digital access The dynamics of the aragonite saturation state (Omega(arag)) were investigated in the eutrophic coastal waters of Guanabara Bay (RJ-Brazil). Large phytoplankton blooms stimulated by a high nutrient enrichment promoted the production of organic matter with strong uptake of dissolved inorganic carbon (DIC) in surface waters, lowering the concentrations of dissolved carbon dioxide (CO2aq), and increasing the pH, Omega(arag) and carbonate ion (CO32- especially during summer. The increase of Omega(arag) related to biological activity was also evident comparing the negative relationship between the Omega(arag) and the apparent utilization of oxygen (AOU), with a very close behavior between the slopes of the linear regression and the Redfield ratio. The lowest values of Omega(arag) were found at low-buffered waters in regions that receive direct discharges from domestic effluents and polluted rivers, with episodic evidences of corrosive waters (Omega(arag) < 1). This study showed that the eutrophication controlled the variations of Omega(arag) in Guanabara Bay. specialized Carbonate chemistry Coastal eutrophication Coastal acidification Phytoplankton blooms BRESIL ATLANTIQUE GUANABARA BAIE 038 036 129 2 729-739 2018 0025-326X https://www.documentation.ird.fr/hor/fdi:010073021 10.1016/j.marpolbul.2017.10.064 0025-326X [F B010073021] https://www.documentation.ird.fr/hor/fdi:010073021 https://www.documentation.ird.fr/intranet/publi/2018/06/010073021.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2018-07-03 2023-07-11 fdi:010073021 fre