Supported by the Academy of Finland (SA128833), the Swedish Research Council Formas (2009-909), the European Community (GOCE CT 003875-2005, ASSEMBLE 227799) and PRIN 2009 – prot. 2009JS5YX9_005.
Intraspecific variability in the response of bloom-forming marine microalgae to changed climate conditions
Article first published online: 14 MAY 2012
© 2011 The Authors. MicrobiologyOpen published by Blackwell Publishing Ltd.
This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.
Ecology and Evolution
Volume 2, Issue 6, pages 1195–1207, June 2012
How to Cite
Kremp, A., Godhe, A., Egardt, J., Dupont, S., Suikkanen, S., Casabianca, S. and Penna, A. (2012), Intraspecific variability in the response of bloom-forming marine microalgae to changed climate conditions. Ecology and Evolution, 2: 1195–1207. doi: 10.1002/ece3.245
- Issue published online: 12 JUN 2012
- Article first published online: 14 MAY 2012
- Received: 19 December 2011; Revised: 24 February 2012; Accepted: 24 February 2012
- culture experiments;
- phenotypic variability;
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 water temperature and atmospheric pCO2 conditions, with potentially severe consequences for the coastal ecosystem.