Interactive effects of warming and ocean acidification on the Arctic picoeukaryote Micromonas pusilla

• Main Authors: Hoppe, Clara Jule Marie, Flintrop, Clara, Rost, Björn
• Format: Dataset
• Language: English
• Published: PANGAEA 2018
• Subjects: Alkalinity; total; Aragonite saturation state; Arctic; Bicarbonate ion; Biomass/Abundance/Elemental composition; Bottles or small containers/Aquaria (<20 L); Calcite saturation state; Calculated using seacarb after Nisumaa et al. (2010); Carbon; inorganic; dissolved; organic; particulate; per cell; production per cell; particulate/chlorophyll a ratio; Carbon/Nitrogen ratio; Carbonate ion; Carbonate system computation flag; Carbon dioxide; Chlorophyll a per cell; Chlorophyta; Coast and continental shelf; Division rate constant; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Functional absorption cross section; Growth/Morphology; Growth rate; Identification; Laboratory experiment; Maximal absolute electron transfer rate; Maximum light use efficiency; Micromonas pusilla; Non photochemical quenching; maximum; OA-ICC; Ocean Acidification International Coordination Centre; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); Particulate organic nitrogen per cell; Pelagos; pH; Photochemical quantum yield; Photosystem II re-opening rate; Arctic Ocean; Climate change; Ocean acidification
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.892370; https://doi.org/10.1594/PANGAEA.892370

In the Arctic Ocean, climate change effects such as warming and ocean acidification (OA) are manifesting faster than in other regions. Yet, we are lacking a mechanistic understanding of the interactive effects of these drivers on Arctic primary producers. In the current study, one of the most abundant species of the Arctic Ocean, the prasinophyte Micromonas pusilla, was exposed to a range of different pCO2levels at two temperatures representing realistic scenarios for current and future conditions. We observed that warming and OA synergistically increased growth rates at intermediate to high pCO2 levels. Furthermore, elevated temperatures shifted the pCO2-optimum of biomass production to higher levels. Based on changes in cellular composition and photophysiology, we hypothesise that the observed synergies can be explained by beneficial effects of warming on carbon fixation in combination with facilitated carbon acquisition under OA. Our findings help to understand the higher abundances of picoeukaryotes such as M. pusilla under OA, as has been observed in many mesocosm studies.