Seawater carbonate chemistry and carbonate chemistry in the microenvironment within cyanobacterial aggregates ...

• Main Authors: Eichner, Meri, Wolf-Gladrow, Dieter A, Ploug, Helle
• Format: Dataset
• Language: English
• Published: PANGAEA 2021
• Subjects: Acid-base regulation; Bacteria; Baltic Sea; Bottles or small containers/Aquaria <20 L; Coast and continental shelf; Cyanobacteria; Dolichospermum sp.; Heterotrophic prokaryotes; Laboratory experiment; Nodularia spumigena; Pelagos; Respiration; Single species; Temperate; Type; Species; Registration number of species; Uniform resource locator/link to reference; Identification; Treatment; Light mode; pH; pH, standard deviation; Hydrogen ion concentration; Hydrogen ion concentration, standard deviation; Ratio; Oxygen; Oxygen, standard deviation; Oxygen evolution per individual; Oxygen evolution, standard deviation; Oxygen evolution; Salinity; Temperature, water; Alkalinity, total; Alkalinity, total, standard deviation; Carbon, inorganic, dissolved; Carbon, inorganic, dissolved, standard deviation; Partial pressure of carbon dioxide water at sea surface temperature wet air; Carbonate system computation flag; Carbon dioxide; Fugacity of carbon dioxide water at sea surface temperature wet air; Bicarbonate ion; Carbonate ion; Aragonite saturation state; Calcite saturation state; Experiment; Potentiometric; Potentiometric titration; Colorimetric; Calculated using CO2SYS; Ocean acidification
• Online Access: https://dx.doi.org/10.1594/pangaea.943567; https://doi.pangaea.de/10.1594/PANGAEA.943567

Photosynthesis and respiration cause distinct chemical microenvironments within cyanobacterial aggregates. Here, we used microsensors and a diffusion–reaction model to characterize gradients in carbonate chemistry and investigate how these are affected by ocean acidification in Baltic vs. Pacific aggregates (Nodularia and Dolichospermum vs. Trichodesmium). Microsensor measurements of O2 and pH were performed under in situ and expected future pCO2 levels on Nodularia and Dolichospermum aggregates collected in the Baltic Sea. Under in situ conditions, O2 and pH levels within the aggregates covered ranges of 80–175% air saturation and 7.7–9.4 in dark and light, respectively. Carbon uptake in the light was predicted to reduce HCO3− by 100–150 μmol/L and CO2 by 3–6 μmol/L in the aggregate center compared to outside, inducing strong CO2 depletion (down to 0.5 μmol/L CO2 remaining in the center) even when assuming that HCO3− covered 80–90% of carbon uptake. Under ocean acidification conditions, enhanced CO2 ... : In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2021) was used to compute a complete and consistent set of carbonate system variables, as described by Nisumaa et al. (2010). In this dataset the original values were archived in addition with the recalculated parameters (see related PI). The date of carbonate chemistry calculation by seacarb is 2022-04-28. ...