Seawater carbonate chemistry and maximum growth rates of Skeletonema marinoi and Alexandrium ostenfeldii, toxin composition of Alexandrium ostenfeldii in a laboratory experiment

• Main Authors: Kremp, Anke, Godhe, Anna, Egardt, Jenny, Dupont, Sam, Suikkanen, Sanna, Casabianca, Silvia, Penna, Antonella
• Format: Dataset
• Language: English
• Published: PANGAEA 2012
• Subjects: Aland_Foglo; Alexandrium ostenfeldii; Alkalinity; total; standard error; Aragonite saturation state; Baltic Sea; Bicarbonate ion; Bottles or small containers/Aquaria (<20 L); Calcite saturation state; Calculated using CO2SYS; Calculated using seacarb after Nisumaa et al. (2010); Carbon; inorganic; dissolved; Carbonate ion; Carbonate system computation flag; Carbon dioxide; Cellular gonyautoxins 2,3; Cellular paralytic shellfish toxin; Cellular saxitoxin; Cellular saxitoxin/cellular total paralytic shellfish toxin ratio; Chromista; Event label; EXP; Experiment; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Growth/Morphology; Growth rate; High Performance Liquid Chromatography (HPLC); Identification; Immunology/Self-protection; Laboratory experiment; Laboratory strains; LATITUDE; LONGITUDE; Mediterranean Sea; North Atlantic; NW_Adriatic_Sea; OA-ICC; Ocean Acidification International Coordination Centre; Ochrophyta; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); Pelagos; pH; Ocean acidification
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.823376; https://doi.org/10.1594/PANGAEA.823376

Phytoplankton populations can display high levels of genetic diversity that, when reflected by phenotypic variability, may stabilize a species response to environmental changes. We studied the effects of increased temperature and CO2 availability as predicted consequences of global change, on 16 genetically different isolates of the diatom Skeletonema marinoi from the Adriatic Sea and the Skagerrak (North Sea), and on eight strains of the PST (paralytic shellfish toxin)-producing dinoflagellate Alexandrium ostenfeldii from the Baltic Sea. Maximum growth rates were estimated in batch cultures of acclimated isolates grown for five to 10 generations in a factorial design at 20 and 24 °C, and present day and next century applied atmospheric pCO2, respectively. In both species, individual strains were affected in different ways by increased temperature and pCO2. The strongest response variability, buffering overall effects, was detected among Adriatic S. marinoi strains. Skagerrak strains showed a more uniform response, particularly to increased temperature, with an overall positive effect on growth. Increased temperature also caused a general growth stimulation in A. ostenfeldii, despite notable variability in strain-specific response patterns. Our data revealed a significant relationship between strain-specific growth rates and the impact of pCO2 on growth-slow growing cultures were generally positively affected, while fast growing cultures showed no or negative responses to increased pCO2. Toxin composition of A. ostenfeldii was consistently altered by elevated temperature and increased CO2 supply in the tested strains, resulting in overall promotion of saxitoxin production by both treatments. Our findings suggest that phenotypic variability within populations plays an important role in the adaptation of phytoplankton to changing environments, potentially attenuating short-term effects and forming the basis for selection. In particular, A. ostenfeldii blooms may expand and increase in toxicity under increased ...