Long-term acclimation to elevated pCO2 alters carbon metabolism and reduces growth in the Antarctic diatom Nitzschia lecointei

• Main Authors: Torstensson, Anders, Hedblom, Mikael, Mattsdotter Björk, M y, Chierici, Melissa, Wulff, Angela
• Format: Dataset
• Language: English
• Published: PANGAEA - Data Publisher for Earth & Environmental Science 2015
• Subjects: Antarctic; Bottles or small containers/Aquaria <20 L; Chromista; Growth/Morphology; Laboratory experiment; Laboratory strains; Nitzschia lecointei; Ochrophyta; Other metabolic rates; Pelagos; Phytoplankton; Primary production/Photosynthesis; Single species; Type; Species; Registration number of species; Uniform resource locator/link to reference; Sample ID; Identification; Partial pressure of carbon dioxide water at sea surface temperature wet air; Comment; Number; Time in days; Cell density; Growth rate; Generation; Bacteria; Bacterial carbon production; Bacterial carbon production per cell; Primary production of carbon; Percentage; Primary production of carbon per cell; Dry mass per cell; Salinity; Temperature, water; pH; Alkalinity, total; Carbonate system computation flag; Carbon dioxide; Fugacity of carbon dioxide water at sea surface temperature wet air; Bicarbonate ion; Carbonate ion; Carbon, inorganic, dissolved; Aragonite saturation state; Calcite saturation state; Spectrophotometric; Potentiometric titration; Calculated using seacarb after Nisumaa et al. 2010; Ocean Acidification International Coordination Centre OA-ICC; The Antarctic; Antarc*; Ocean acidification; Sea ice
• Online Access: https://dx.doi.org/10.1594/pangaea.869122; https://doi.pangaea.de/10.1594/PANGAEA.869122

Increasing atmospheric CO2 levels are driving changes in the seawater carbonate system, resulting in higher pCO2 and reduced pH (ocean acidification). Many studies on marine organisms have focused on short-term physiological responses to increased pCO2, and few on slow-growing polar organisms with a relative low adaptation potential. In order to recognize the consequences of climate change in biological systems, acclimation and adaptation to new environments are crucial to address. In this study, physiological responses to long-term acclimation (194 days, approx. 60 asexual generations) of three pCO2 levels (280, 390 and 960 µatm) were investigated in the psychrophilic sea ice diatom Nitzschia lecointei. After 147 days, a small reduction in growth was detected at 960 µatm pCO2. Previous short-term experiments have failed to detect altered growth in N. lecointei at high pCO2, which illustrates the importance of experimental duration in studies of climate change. In addition, carbon metabolism was significantly affected by the long-term treatments, resulting in higher cellular release of dissolved organic carbon (DOC). In turn, the release of labile organic carbon stimulated bacterial productivity in this system. We conclude that long-term acclimation to ocean acidification is important for N. lecointei and that carbon overconsumption and DOC exudation may increase in a high-CO2 world. : 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 is 2016-11-30.