Seawater carbonate chemistry and photosystem II photoinactivation of the coastal diatom Thalassiosira pseudonana in a laboratory experiment

• Main Authors: Li, Gang, Campbell, Douglas A
• Format: Dataset
• Language: English
• Published: PANGAEA 2013
• Subjects: Alkalinity; total; Aragonite saturation state; Bicarbonate ion; Bottles or small containers/Aquaria (<20 L); Calcite saturation state; Calculated using CO2SYS; Calculated using seacarb after Nisumaa et al. (2010); Carbon; inorganic; dissolved; organic; particulate; per cell; Carbon/Nitrogen ratio; Carbonate ion; Carbonate system computation flag; Carbon dioxide; Cell biovolume; Cell density; CF1 subunit of ATP synthase protein; Chlorophyll a per cell; Chromista; Cytochrome c1; Date; Effective absorbance cross-section of photosystem II; Element analyser CNS; Elementar Vario EL; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Growth/Morphology; Growth rate; Identification; Irradiance; Laboratory experiment; Laboratory strains; Light; Nitrogen; Not applicable; OA-ICC; Ocean Acidification International Coordination Centre; Ochrophyta; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); Pelagos; pH; Phosphate; Photochemical quenching; Psi; Ocean acidification
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.824663; https://doi.org/10.1594/PANGAEA.824663

We studied the interactive effects of pCO2 and growth light on the coastal marine diatom Thalassiosira pseudonana CCMP 1335 growing under ambient and expected end-of-the-century pCO2 (750 ppmv), and a range of growth light from 30 to 380 µmol photons/m**2/s. Elevated pCO2 significantly stimulated the growth of T. pseudonana under sub-saturating growth light, but not under saturating to super-saturating growth light. Under ambient pCO2 susceptibility to photoinactivation of photosystem II (sigma i) increased with increasing growth rate, but cells growing under elevated pCO2 showed no dependence between growth rate and sigma i, so under high growth light cells under elevated pCO2 were less susceptible to photoinactivation of photosystem II, and thus incurred a lower running cost to maintain photosystem II function. Growth light altered the contents of RbcL (RUBISCO) and PsaC (PSI) protein subunits, and the ratios among the subunits, but there were only limited effects on these and other protein pools between cells grown under ambient and elevated pCO2.