Resilience to temperature and pH changes in a future climate change scenario in six strains of the polar diatom Fragilariopsis cylindrus, supplement to: Pančić, M; Hansen, Per Juel; Tammilehto, A; Lundholm, Nina (2015): Resilience to temperature and pH changes in a future climate change scenario in six strains of the polar diatom Fragilariopsis cylindrus. Biogeosciences, 12(14), 4235-4244

• Main Authors: Pančić, M, Hansen, Per Juel, Tammilehto, A, Lundholm, Nina
• Format: Dataset
• Language: English
• Published: PANGAEA - Data Publisher for Earth & Environmental Science 2015
• Subjects: Bottles or small containers/Aquaria <20 L; Chromista; Coast and continental shelf; Fragilariopsis cylindrus; Growth/Morphology; Laboratory experiment; North Atlantic; Ochrophyta; Pelagos; Polar; Single species; Temperature; Type; Species; Registration number of species; Uniform resource locator/link to reference; Strain; pH; Temperature, water; Growth rate; Time in days; Cumulative cell concentration, logarithm; Cumulative cell concentration, logarithm, standard deviation; Salinity; Carbon, inorganic, dissolved; Carbon, inorganic, dissolved, standard deviation; Bicarbonate; Bicarbonate, standard deviation; Carbonate ion; Carbonate ion, standard deviation; Carbon dioxide; Carbon dioxide, standard deviation; Carbonate system computation flag; Fugacity of carbon dioxide water at sea surface temperature wet air; Partial pressure of carbon dioxide water at sea surface temperature wet air; Bicarbonate ion; Alkalinity, total; Aragonite saturation state; Calcite saturation state; Potentiometric; Infrared gas analyzer; Calculated using CO2SYS; Calculated using seacarb after Nisumaa et al. 2010; Ocean Acidification International Coordination Centre OA-ICC; Greenland; Ocean acidification
• Online Access: https://dx.doi.org/10.1594/pangaea.859285; https://doi.pangaea.de/10.1594/PANGAEA.859285

The effects of ocean acidification and increased temperature on physiology of six strains of the polar diatom Fragilariopsis cylindrus from Greenland were investigated. Experiments were performed under manipulated pH levels (8.0, 7.7, 7.4, and 7.1) and different temperatures (1, 5, and 8 °C) to simulate changes from present to plausible future levels. Each of the 12 scenarios was run for 7 days, and a significant interaction between temperature and pH on growth was detected. By combining increased temperature and acidification, the two factors counterbalanced each other, and therefore no effect on the growth rates was found. However, the growth rates increased with elevated temperatures by 20-50% depending on the strain. In addition, a general negative effect of increasing acidification on growth was observed. At pH 7.7 and 7.4, the growth response varied considerably among strains. However, a more uniform response was detected at pH 7.1 with most of the strains exhibiting reduced growth rates by 20-37% compared to pH 8.0. It should be emphasized that a significant interaction between temperature and pH was found, meaning that the combination of the two parameters affected growth differently than when considering one at a time. Based on these results, we anticipate that the polar diatom F. cylindrus will be unaffected by changes in temperature and pH within the range expected by the end of the century. In each simulated scenario, the variation in growth rates among the strains was larger than the variation observed due to the whole range of changes in either pH or temperature. Climate change may therefore not affect the species as such, but may lead to changes in the population structure of the species, with the strains exhibiting high phenotypic plasticity, in terms of temperature and pH tolerance towards future conditions, dominating the population. : In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2015) 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 2016-04-01.