Warming will affect phytoplankton differently: evidence through a mechanistic approach

• Published in: Proceedings of the Royal Society. B, Biological sciences Vol. 278; no. 1724; pp. 3534 - 3543
• Main Authors: Huertas, I. Emma, Rouco, Mónica, López-Rodas, Victoria, Costas, Eduardo
• Format: Journal Article
• Language: English
• Published: England Royal Society 07.12.2011; The Royal Society
• Subjects: Adaptation, Physiological; aquatic communities; aquatic ecosystems; aquatic food webs; biogeochemical cycles; Biological adaptation; Biological Evolution; Climate Change; Ecosystem; Evolution; evolutionary adaptation; Genetic Adaptation; Genetic mutation; Global warming; Greenhouse Effect; habitats; heat tolerance; Hot Temperature; Oceans; Phytoplankton; Phytoplankton - genetics; Phytoplankton - growth & development; Phytoplankton - physiology; primary productivity; Ratchet Technique; Species Specificity; Symbiosis; temperature; Warming; Water temperature
• ISSN: 0962-8452; 1471-2954; 1471-2945
• DOI: 10.1098/rspb.2011.0160

Although the consequences of global warming in aquatic ecosystems are only beginning to be revealed, a key to forecasting the impact on aquatic communities is an understanding of individual species' vulnerability to increased temperature. Despite their microscopic size, phytoplankton support about half of the global primary production, drive essential biogeochemical cycles and represent the basis of the aquatic food web. At present, it is known that phytoplankton are important targets and, consequently, harbingers of climate change in aquatic systems. Therefore, investigating the capacity of phytoplankton to adapt to the predicted warming has become a relevant issue. However, considering the polyphyletic complexity of the phytoplankton community, different responses to increased temperature are expected. We experimentally tested the effects of warming on 12 species of phytoplankton isolated from a variety of environments by using a mechanistic approach able to assess evolutionary adaptation (the so-called ratchet technique). We found different degrees of tolerance to temperature rises and an interspecific capacity for genetic adaptation. The thermal resistance level reached by each species is discussed in relation to their respective original habitats. Our study additionally provides evidence on the most resistant phytoplankton groups in a future warming scenario.