Two intertidal, non-calcifying macroalgae (Palmaria palmata and Saccharina latissima) show complex and variable responses to short-term CO2 acidification, supplement to: Nunes, Joana; McCoy, Sophie J; Findlay, Helen S; Hopkins, Frances E; Kitidis, Vassilis; Queirós, Ana M; Rayner, Lucy; Widdicombe, Stephen (2016): Two intertidal, non-calcifying macroalgae (Palmaria palmata and Saccharina latissima) show complex and variable responses to short-term CO2 acidification. ICES Journal of Marine Science, 73(3), 887-896

• Main Authors: Nunes, Joana, McCoy, Sophie J, Findlay, Helen S, Hopkins, Frances E, Kitidis, Vassilis, Queirós, Ana M, Rayner, Lucy, Widdicombe, Stephen
• Format: Dataset
• Language: English
• Published: PANGAEA - Data Publisher for Earth & Environmental Science 2016
• Subjects: Benthos; Chromista; Coast and continental shelf; Containers and aquaria 20-1000 L or < 1 m**2; Growth/Morphology; Laboratory experiment; Macroalgae; North Atlantic; Ochrophyta; Other metabolic rates; Palmaria palmata; Plantae; Primary production/Photosynthesis; Respiration; Rhodophyta; Saccharina latissima; Single species; Temperate; Type; Species; Registration number of species; Uniform resource locator/link to reference; Identification; Duration, number of days; Treatment; Respiration rate, oxygen; Net primary production of oxygen; Gross primary production of oxygen; Position; Dimethylsulfoniopropionate; Width; Height; Area; Nitrite; Nitrate and Nitrite; Ammonium; Silicate; Phosphate; Nitrate; Migration; Temperature, water; Temperature, water, standard deviation; Salinity; Salinity, standard deviation; pH; pH, standard deviation; Alkalinity, total; Alkalinity, total, standard deviation; Partial pressure of carbon dioxide water at sea surface temperature wet air; Partial pressure of carbon dioxide, standard deviation; Bicarbonate ion; Bicarbonate ion, standard deviation; Carbonate ion; Carbonate ion, standard deviation; Carbonate system computation flag; Carbon dioxide; Fugacity of carbon dioxide water at sea surface temperature wet air; Carbon, inorganic, dissolved; Aragonite saturation state; Calcite saturation state; Experiment; Potentiometric; Potentiometric titration; Calculated using CO2SYS; Calculated using seacarb after Nisumaa et al. 2010; Ocean Acidification International Coordination Centre OA-ICC; Nunes; Rayner; Findlay; McCoy; Ocean acidification
• Online Access: https://dx.doi.org/10.1594/pangaea.859057; https://doi.pangaea.de/10.1594/PANGAEA.859057

Ocean acidification, the result of increased dissolution of carbon dioxide (CO2) in seawater, is a leading subject of current research. The effects of acidification on non-calcifying macroalgae are, however, still unclear. The current study reports two 1-month studies using two different macroalgae, the red alga Palmaria palmata (Rhodophyta) and the kelp Saccharina latissima (Phaeophyta), exposed to control (pHNBS = 8.04) and increased (pHNBS = 7.82) levels of CO2-induced seawater acidification. The impacts of both increased acidification and time of exposure on net primary production (NPP), respiration (R), dimethylsulphoniopropionate (DMSP) concentrations, and algal growth have been assessed. In P. palmata, although NPP significantly increased during the testing period, it significantly decreased with acidification, whereas R showed a significant decrease with acidification only. S. latissima significantly increased NPP with acidification but not with time, and significantly increased R with both acidification and time, suggesting a concomitant increase in gross primary production. The DMSP concentrations of both species remained unchanged by either acidification or through time during the experimental period. In contrast, algal growth differed markedly between the two experiments, in that P. palmata showed very little growth throughout the experiment, while S. latissima showed substantial growth during the course of the study, with the latter showing a significant difference between the acidified and control treatments. These two experiments suggest that the study species used here were resistant to a short-term exposure to ocean acidification, with some of the differences seen between species possibly linked to different nutrient concentrations between the experiments. : In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2015) 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 is 2016-03-18.