Seawater carbonate chemistry and growth and physiology of the marine cyanobacterium Synechococcus (Cyanophyceae)

• Main Authors: Laws, Edward A, McClellan, S Alex
• Format: Dataset
• Language: English
• Published: PANGAEA 2022
• Subjects: Alkalinity; total; Aragonite saturation state; Bacteria; Bicarbonate; Bicarbonate ion; Biomass/Abundance/Elemental composition; Bottles or small containers/Aquaria (<20 L); Calcite saturation state; Calculated using seacarb after Nisumaa et al. (2010); Carbon; inorganic; dissolved; Carbon/Chlorophyll a ratio; Carbon/Nitrogen ratio; Carbonate ion; Carbonate system computation flag; Carbon dioxide; Cyanobacteria; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Growth/Morphology; Growth rate; Initial slope of the photosynthesis-irradiance curve; Irradiance; Laboratory experiment; Laboratory strains; Light; Macro-nutrients; Not applicable; OA-ICC; Ocean Acidification International Coordination Centre; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); Pelagos; pH; Photosynthetic carbon fixation rate; per chlorophyll a; Phytoplankton; Primary production/Photosynthesis; Ratio; Salinity; Single species; Species; unique identification; unique identification (Semantic URI); unique identification (URI); Synechococcus elongatus; Ocean acidification
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.952426; https://doi.org/10.1594/PANGAEA.952426

The marine cyanobacterium Synechococcus elongatus was grown in a continuous culture system to study the interactive effects of temperature, irradiance, nutrient limitation, and the partial pressure of CO2 (pCO2) on its growth and physiological characteristics. Cells were grown on a 14:10 h light:dark cycle at all combinations of low and high irradiance (50 and 300 μmol photons/m**2/s, respectively), low and high pCO2 (400 and 1000 ppmv, respectively), nutrient limitation (nitrate-limited and nutrient-replete conditions), and temperatures of 20–45°C in 5°C increments. The maximum growth rate was ~4.5 · d−1 at 30–35°C. Under nutrient-replete conditions, growth rates at most temperatures and irradiances were about 8% slower at a pCO2 of 1000 ppmv versus 400 ppmv. The single exception was 45°C and high irradiance. Under those conditions, growth rates were ~45% higher at 1000 ppmv. Cellular carbon:nitrogen ratios were independent of temperature at a fixed relative growth rate but higher at high irradiance than at low irradiance. Initial slopes of photosynthesis–irradiance curves were higher at all temperatures under nutrient-replete versus nitrate-limited conditions; they were similar at all temperatures under high and low irradiance, except at 20°C, when they were suppressed at high irradiance. A model of phytoplankton growth in which cellular carbon was allocated to structure, storage, or the light or dark reactions of photosynthesis accounted for the general patterns of cell composition and growth rate. Allocation of carbon to the light reactions of photosynthesis was consistently higher at low versus high light and under nutrient-replete versus nitrate-limited conditions.