Antoni et al. (2025): Olivine and dissolved alkalinity trigger different bacterial community shifts in water and oyster gills: insights from a mesocosm experiment
Dominik Antoni, Marco Rump and Gunnar Gerdts, IN: Frontiers in Microbiomes, https://doi.org/10.3389/frmbi.2025.1659695
This paper provides a risk assessment of two different Ocean Alkalinity Enhancement (OAE) strategies: alkalization with olivine and alkalization with addition of dissolved sodium hydroxide (NaOH). With a mesocosm experiment designed to simulate coastal OAE application, European flat oysters (Ostrea edulis) were chronically exposed to alkalinity-enhanced seawater at two concentrations (250 and 500 µmol·L⁻¹) derived either from olivine weathering or addition with NaOH. The bacterial community composition of both alkalization types was assessed with amplicon sequencing of the 16S rRNA gene and ecotoxicological impacts were compared to a non-alkalized control. The sampling strategy included samples of the treated waters and the gill microbiome of Ostrea edulis.