Marín-Samper et al. (2024): Responses of microbial metabolic rates to non-equilibrated silicate- versus calcium-based ocean alkalinity enhancement
Laura Marín-Samper, Javier Arístegui, Nauzet Hernández-Hernández, Ulf Riebesell IN: Biogeosciences, https://doi.org/10.5194/bg-21-5707-2024
This study contributes to the inaugural exploration of non-equilibrated ocean alkalinity enhancement (OAE). Total alkalinity (TA) was manipulated, with silicate- and calcium-based ΔTA gradients ranging from 0 to 600 µmol L−1, without prior CO2 sequestration, under natural conditions and at a mesocosm scale (∼ 60 m3). This manipulation led to a sustained increase in pH and a decrease in pCO2 throughout the experiment, as full natural equilibration through sea–air gas exchange did not occur. Implemented in a neritic system under post-bloom conditions, a midway mixing event was simulated.