Publication Date:
2024-03-15
Description:
The rise in anthropogenic CO2 and the associated ocean acidification (OA) will change trace metal solubility and speciation, potentially altering Southern Ocean (SO) phytoplankton productivity and species composition. As iron (Fe) sources are important determinants of Fe bioavailability, we assessed the effect of Fe-laden dust versus inorganic Fe (FeCl3) enrichment under ambient and high pCO2 levels (390 and 900 μatm) in a naturally Fe-limited SO phytoplankton community. Despite similar Fe chemical speciation and net particulate organic carbon (POC) production rates, CO2-dependent species shifts were controlled by Fe sources. Final phytoplankton communities of both control and dust treatments were dominated by the same species, with an OA-dependent shift from the diatom Pseudo nitzschia prolongatoides towards the prymnesiophyte Phaeocystis antarctica. Addition of FeCl3 resulted in high abundances of Nitzschia lecointei and Chaetoceros neogracilis under ambient and high pCO2, respectively. These findings reveal that both the characterization of the phytoplankton community at the species level and the use of natural Fe sources are essential for a realistic projection of the biological carbon pump in the Fe-limited pelagic SO under OA. As dust deposition represents a more realistic scenario for the Fe-limited pelagic SO under OA, unaffected net POC production and dominance of P. antarctica can potentially weaken the export of carbon and silica in the future.
Keywords:
Abundance; Abundance, standard deviation; Alkalinity, total; Alkalinity, total, standard deviation; Antarctic; Aragonite saturation state; Bicarbonate ion; Biogenic particulate silica/Carbon, organic, particulate; Biogenic particulate silica/Carbon, organic, particulate, 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); Carbon, inorganic, dissolved; Carbon, inorganic, dissolved, standard deviation; Carbon, organic, particulate, net production; Carbonate ion; Carbonate system computation flag; Carbon dioxide; Cell density; Cell density, standard deviation; Community composition and diversity; Entire community; EXP; Experiment; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Growth rate; Growth rate, standard deviation; Iron, chemically labile; Iron, dissolved; Iron, dissolved, inorganic; Iron, dissolved, standard deviation; Iron, inorganic, conditional stability constants; Iron, inorganic, conditional stability constants, standard deviation; Iron uptake/Carbon, organic, particulate; Iron uptake/Carbon, organic, particulate, standard deviation; Laboratory experiment; Ligand concentration; Ligand concentration, standard deviation; Maximum photochemical quantum yield of photosystem II; Maximum photochemical quantum yield of photosystem II, standard deviation; Micro-nutrients; Nitrate; Nitrate, standard deviation; OA-ICC; Ocean Acidification International Coordination Centre; Open ocean; Other metabolic rates; Partial pressure of carbon dioxide, standard deviation; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); Particulate inorganic carbon per cell; Pelagos; pH; pH, standard deviation; Polar; Polar_front; Primary production/Photosynthesis; Salinity; Side coefficient of dissolved Fe-complex ligands; Temperature, water; Time in days; Time point, descriptive; Treatment; Type
Type:
Dataset
Format:
text/tab-separated-values, 4906 data points
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