https://doi.pangaea.de/10.1594/PANGAEA.996215Rump, MarcoMarcoRump0009-0004-2329-4889Alfred Wegener Institute - Biological Institute HelgolandLannig, GiselaGiselaLannig0000-0002-9210-256XAlfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, BremerhavenBock, ChristianChristianBock0000-0003-0052-3090Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, BremerhavenBenthien, AlbertAlbertBenthien0000-0002-9159-3109Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, BremerhavenPogoda, BernadetteBernadettePogoda0000-0003-3997-426XAlfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, BremerhavenAntoni, DominikDominikAntoniAlfred Wegener Institute - Biological Institute HelgolandGerdts, GunnarGunnarGerdts0000-0003-0872-3927Alfred Wegener Institute - Biological Institute HelgolandTotal alkalinity and pH in the exposure mesocosms of a chronic Ostrea edulis alkalinity-enhancement exposure experimentPANGAEA2026ecotoxicologyocean alkalinity enhancementOstrea edulisEvent labelType of studyIncubation typeExperiment daySampling date/time, experimentTreatmentReplicatespHAlkalinity, totalMesocosm experiment2024-04-17T00:00:00/2025-03-12T00:00:00Datasethttps://doi.pangaea.de/10.1594/PANGAEA.996264https://doi.pangaea.de/10.1594/PANGAEA.996219https://doi.pangaea.de/10.1594/PANGAEA.996220https://doi.pangaea.de/10.1594/PANGAEA.996222https://doi.pangaea.de/10.1594/PANGAEA.996218https://doi.pangaea.de/10.1594/PANGAEA.996216https://doi.pangaea.de/10.1594/PANGAEA.996221https://doi.pangaea.de/10.1594/PANGAEA.996217https://doi.pangaea.de/10.1594/PANGAEA.9962143224 data pointstext/tab-separated-valuesCreative Commons Attribution 4.0 InternationalData access is restricted (moratorium, sensitive data, license constraints)This dataset contains repeated measurements of seawater pH and total alkalinity recorded in the exposure mesocosms, the tanks holding the oysters exposed to five treatments (unamended control, dissolved alkalinity addition with NaOH and CaCl2 at +250 or +500 µmol/kg, and olivine-based coastal enhanced silicate weathering at +250 or +500 µmol/kg) over a 64-day chronic exposure. These treatments mirror those established in the alkalinization mesocosms. Measurements span three sampling intervals, 8 May to 27 May 2024, 29 May to 17 June 2024 and 19 June to 10 July 2024. Measurements were taken predominantly in triplicate per treatment and sampling day. Seawater pH was measured with a pH electrode and total alkalinity by open-cell potentiometric titration, both on a Metrohm 855 Robotic Titrosampler.7.88894454.180327Helgoland, GermanyBundesamt für Naturschutzhttps://doi.org/10.13039/5011000104153522830300DEFINE2