CO2-driven seawater acidification increases photochemical stress in a green alga, supplement to: Liu, Yuting; Xu, Juntian; Gao, Kunshan (2012): CO2-driven seawater acidification increases photochemical stress in a green alga. Phycologia, 51(5), 562-566

• Main Authors: Liu, Yuting, Xu, Juntian, Gao, Kunshan
• Format: Dataset
• Language: English
• Published: PANGAEA - Data Publisher for Earth & Environmental Science 2012
• Subjects: Benthos; Bottles or small containers/Aquaria <20 L; Chlorophyta; Coast and continental shelf; Laboratory experiment; Macroalgae; North Pacific; Plantae; Primary production/Photosynthesis; Single species; Temperate; Ulva prolifera; Species; Identification; Treatment; Irradiance; Electron transport rate, relative; Electron transport rate, relative, standard deviation; Time in seconds; Effective quantum yield; Effective quantum yield, standard deviation; Non photochemical quenching; Non photochemical quenching, standard deviation; Carbon, inorganic, dissolved; Salinity; Temperature, water; pH; pH, standard deviation; Carbon, inorganic, dissolved, standard deviation; Carbonate system computation flag; Carbon dioxide; Partial pressure of carbon dioxide water at sea surface temperature wet air; Fugacity of carbon dioxide water at sea surface temperature wet air; Bicarbonate ion; Carbonate ion; Alkalinity, total; Aragonite saturation state; Calcite saturation state; Experiment; Potentiometric; Calculated using seacarb after Nisumaa et al. 2010; Ocean Acidification International Coordination Centre OA-ICC; Pacific; Ocean acidification
• Online Access: https://dx.doi.org/10.1594/pangaea.830590; https://doi.pangaea.de/10.1594/PANGAEA.830590

Increased CO2 and associated acidification in seawater, known as ocean acidification, decreases calcification of most marine calcifying organisms. However, there is little information available on how marine macroalgae would respond to the chemical changes caused by seawater acidification. We hypothesized that down-regulation of bicarbonate acquisition by algae under increased acidity and CO2 levels would lower the threshold above which photosynthetically active radiation (PAR) becomes excessive. Juveniles of Ulva prolifera derived from zoospores were grown at ambient (390 µatm) and elevated (1000 µatm) CO2 concentrations for 80 days before the hypothesis was tested. Here, the CO2-induced seawater acidification increased the quantum yield under low levels of light, but induced higher nonphotochemical quenching under high light. At the same time, the PAR level at which photosynthesis became saturated was decreased and the photosynthetic affinity for CO2 or inorganic carbon decreased in the high-CO2 grown plants. These findings indicated that ocean acidification, as an environmental stressor, can reduce the threshold above which PAR becomes excessive. : In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Lavigne and Gattuso, 2011) 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 2014-03-03.