Publication Date:
2024-03-15
Description:
Elemental contents change with shifts in macromolecular composition of marine phytoplankton. Recent studies focus on the responses of elemental contents of coccolithophores, a major calcifying phytoplankton group, to changing carbonate chemistry, caused by the dissolution of anthropogenically derived CO2 into the surface ocean. However, the effects of changing carbonate chemistry on biomacromolecules, such as protein and carbohydrate of coccolithophores, are less documented. Here, we disentangled the effects of elevated dissolved inorganic carbon (DIC) concentration (900 to 4,930μmol/kg) and reduced pH value (8.04 to 7.70) on physiological rates, elemental contents, and macromolecules of the coccolithophore Emiliania huxleyi. Compared to present DIC concentration and pH value, combinations of high DIC concentration and low pH value (ocean acidification) significantly increased pigments content, particulate organic carbon (POC), and carbohydrate content and had less impact on growth rate, maximal relative electron transport rate (rETRmax), particulate organic nitrogen (PON), and protein content. In high pH treatments, elevated DIC concentration significantly increased growth rate, pigments content, rETRmax, POC, particulate inorganic carbon (PIC), protein, and carbohydrate contents. In low pH treatments, the extents of the increase in growth rate, pigments and carbohydrate content were reduced. Compared to high pH value, under low DIC concentration, low pH value significantly increased POC and PON contents and showed less impact on protein and carbohydrate contents; however, under high DIC concentration, low pH value significantly reduced POC, PON, protein, and carbohydrate contents. These results showed that reduced pH counteracted the positive effects of elevated DIC concentration on growth rate, rETRmax, POC, PON, carbohydrate, and protein contents. Elevated DIC concentration and reduced pH acted synergistically to increase the contribution of carbohydrate–carbon to POC, and antagonistically to affect the contribution of protein–nitrogen to PON, which further shifted the carbon/nitrogen ratio of E. huxleyi.
Keywords:
Alkalinity, total; Alkalinity, total, standard deviation; Aragonite saturation state; Bicarbonate ion; Bicarbonate ion, standard deviation; Biomass/Abundance/Elemental composition; Bottles or small containers/Aquaria (〈20 L); Calcite saturation state; Calculated using CO2SYS; Calculated using seacarb after Nisumaa et al. (2010); Carbohydrates, per cell; Carbohydrates, total, standard deviation; Carbon, inorganic, dissolved; Carbon, inorganic, dissolved, standard deviation; Carbon, inorganic, particulate, per cell; Carbon, inorganic, particulate, standard deviation; Carbon, organic, particulate; Carbon, organic, particulate, per cell; Carbon, organic, particulate, standard deviation; Carbon, organic, particulate/Nitrogen, organic, particulate ratio; Carbon, organic, particulate/Nitrogen, organic, particulate ratio, standard deviation; Carbonate ion; Carbonate ion, standard deviation; Carbonate system computation flag; Carbon dioxide; Carbon dioxide, standard deviation; Carotenoids, standard deviation; Carotenoids/Chlorophyll a ratio; Carotenoids/Chlorophyll a ratio, standard deviation; Carotenoids per cell; Chlorophyll a, standard deviation; Chlorophyll a per cell; Chromista; Emiliania huxleyi; Experiment duration; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Growth/Morphology; Growth rate; Growth rate, standard deviation; Haptophyta; Laboratory experiment; Laboratory strains; Light saturation point; Light saturation point, standard deviation; Light use efficiency; Light use efficiency, standard deviation; Maximal electron transport rate, relative; Maximal electron transport rate, relative, standard deviation; Nitrogen, organic, particulate; Nitrogen, organic, particulate, per cell; Nitrogen, organic, particulate, standard deviation; Not applicable; OA-ICC; Ocean Acidification International Coordination Centre; Other; Partial pressure of carbon dioxide, standard deviation; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); Particulate inorganic carbon/particulate organic carbon ratio; Particulate inorganic carbon/particulate organic carbon ratio, standard deviation; Pelagos; pH; pH, standard deviation; Phytoplankton; Potentiometric; Potentiometric titration; Primary production/Photosynthesis; Protein per cell; Proteins, standard deviation; Registration number of species; Salinity; Single species; Species; Temperature, water; Treatment; Type; Uniform resource locator/link to reference
Type:
Dataset
Format:
text/tab-separated-values, 284 data points
Permalink
