Seawater carbonate chemistry and data of physiological response of a golden tide alga (Sargassum muticum) to the interaction of ocean acidification and phosphorus enrichment, supplement to: Xu, Zhiguang; Gao, Guang; Xu, Juntian; Wu, Hongyan (2017): Physiological response of a golden tide alga (Sargassum muticum) to the interaction of ocean acidification and phosphorus enrichment. Biogeosciences, 14(3), 671-681

• Main Authors: Xu, Zhiguang, Gao, Guang, Xu, Juntian, Wu, Hongyan
• Format: Dataset
• Language: English
• Published: PANGAEA - Data Publisher for Earth & Environmental Science 2017
• Subjects: Benthos; Bottles or small containers/Aquaria <20 L; Chromista; Coast and continental shelf; Growth/Morphology; Laboratory experiment; Macroalgae; Macro-nutrients; North Pacific; Ochrophyta; Other metabolic rates; Primary production/Photosynthesis; Respiration; Sargassum muticum; Single species; Temperate; Type; Species; Registration number of species; Uniform resource locator/link to reference; Experiment duration; Treatment; Growth; Growth rate, standard deviation; Net photosynthesis rate, oxygen; Net photosynthesis rate, standard deviation; Carbon, inorganic, dissolved; Chlorophyll a; Chlorophyll a, standard deviation; Nitrate uptake rate; Nitrate uptake rate, standard deviation; Nitrate reductase activity; Nitrate reductase activity, standard deviation; Carbohydrates, soluble; Carbohydrates, soluble, standard deviation; Protein, soluble; Protein, standard deviation; Respiration rate, oxygen; Respiration rate, oxygen, standard deviation; Temperature, water; Salinity; pH; pH, 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; Carbon dioxide; Carbon dioxide, standard deviation; Carbon, inorganic, dissolved, standard deviation; Alkalinity, total; Alkalinity, total, standard deviation; Carbonate system computation flag; Fugacity of carbon dioxide water at sea surface temperature wet air; Aragonite saturation state; Calcite saturation state; Experiment; Potentiometric; Calculated using CO2SYS; Potentiometric titration; 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.875342; https://doi.pangaea.de/10.1594/PANGAEA.875342

The development of golden tides is potentially influenced by global change factors, such as ocean acidification and eutrophication, but related studies are very scarce. In this study, we cultured a golden tide alga, Sargasssum muticum, at two levels of pCO2 (400 and 1000 µatm) and phosphate (0.5 and 40?µM) to investigate the interactive effects of elevated pCO2 and phosphate on the physiological properties of the thalli. Higher pCO2 and phosphate (P) levels alone increased the relative growth rate by 41 and 48%, the net photosynthetic rate by 46 and 55 %, and the soluble carbohydrates by 33 and 62 %, respectively, while the combination of these two levels did not promote growth or soluble carbohydrates further. The higher levels of pCO2 and P alone also enhanced the nitrate uptake rate by 68 and 36 %, the nitrate reductase activity (NRA) by 89 and 39 %, and the soluble protein by 19 and 15 %, respectively. The nitrate uptake rate and soluble protein was further enhanced, although the nitrate reductase activity was reduced when the higher levels of pCO2 and P worked together. The higher pCO2 and higher P levels alone did not affect the dark respiration rate of the thalli, but together they increased it by 32 % compared to the condition of lower pCO2 and lower P. The neutral effect of the higher levels of pCO2 and higher P on growth and soluble carbohydrates, combined with the promoting effect on soluble protein and dark respiration, suggests that more energy was drawn from carbon assimilation to nitrogen assimilation under conditions of higher pCO2 and higher P; this is most likely to act against the higher pCO2 that caused acid-base perturbation via synthesizing H+ transport-related protein. Our results indicate that ocean acidification and eutrophication may not boost golden tide events synergistically, although each one has a promoting effect. : In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2016) 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 2017-05-17.