Seawater carbonate chemistry, chlorophyll a and phosphate during experiments with Trichodesmium erythraeum IMS101 (CCMP1985), 2010

• Main Authors: Kranz, Sven A, Wolf-Gladrow, Dieter A, Nehrke, Gernot, Langer, Gerald, Rost, Björn
• Format: Dataset
• Language: English
• Published: PANGAEA 2010
• Subjects: Alkalinity; Gran titration (Gran; 1950); total; Aragonite saturation state; Auto-analyzer; Technicon Traacs 800; Bacteria; Bicarbonate ion; BIOACID; Biological Impacts of Ocean Acidification; Bottles or small containers/Aquaria (<20 L); Calcite saturation state; Calculated using CO2SYS; Calculated using seacarb after Nisumaa et al. (2010); Carbon; inorganic; dissolved; Carbonate ion; Carbonate system computation flag; Carbon dioxide; Chlorophyll a; Comment; Conductivity meter (WTW; Weilheim; Gemany); Cyanobacteria; EPOCA; EUR-OCEANS; European network of excellence for Ocean Ecosystems Analysis; European Project on Ocean Acidification; Experimental treatment; Experiment day; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Laboratory experiment; Laboratory strains; Light:Dark cycle; Measured; Not applicable; OA-ICC; Ocean Acidification International Coordination Centre; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); Pelagos; pH; Phosphate; Phytoplankton; Radiation; photosynthetically active; Salinity; Ocean acidification
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.777419; https://doi.org/10.1594/PANGAEA.777419

In this laboratory study, we monitored the buildup of biomass and concomitant shift in seawater carbonate chemistry over the course of a Trichodesmium bloom under different phosphorus (P) availability. During exponential growth, dissolved inorganic carbon (DIC) decreased, while pH increased until maximum cell densities were reached. Once P became depleted, DIC decreased even further and total alkalinity (TA) dropped, accompanied by precipitation of aragonite. Under P-replete conditions, DIC increased and TA remained constant in the postbloom phase. A diffusion-reaction model was employed to estimate changes in carbonate chemistry of the diffusive boundary layer. This study demonstrates that Trichodesmium can induce precipitation of aragonite from seawater and further provides possible explanations about underlying mechanisms.