SHORT‐ VERSUS LONG‐TERM RESPONSES TO CHANGING CO2 IN A COASTAL DINOFLAGELLATE BLOOM: IMPLICATIONS FOR INTERSPECIFIC COMPETITIVE INTERACTIONS AND COMMUNITY STRUCTURE. (4th January 2013)

• Record Type: Journal Article
• Authors: Tatters, Avery O.; Schnetzer, Astrid; Fu, Feixue; Lie, Alle Y.A.; Caron, David A.; Hutchins, David A.
• Is Part Of: Evolution. Volume 67:Number 7(2013:Jul.)
• Page Start: 1879
• Page End: 1891
• Publication Date: 2013-01-04
• Subjects: Evolution -- Periodicals; Heredity -- Periodicals; Évolution (Biologie) -- Périodiques; Hérédité -- Périodiques; 338.47004094
• DOI: 10.1111/evo.12029
• Languages: English
• ISSNs: 0014-3820

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <p>Increasing <italic>p</italic>CO<sub>2</sub> (partial pressure of CO<sub>2</sub>) in an "acidified" ocean will affect phytoplankton community structure, but manipulation experiments with assemblages briefly acclimated to simulated future conditions may not accurately predict the long‐term evolutionary shifts that could affect inter‐specific competitive success. We assessed community structure changes in a natural mixed dinoflagellate bloom incubated at three <italic>p</italic>CO<sub>2</sub> levels (230, 433, and 765 ppm) in a short‐term experiment (2 weeks). The four dominant species were then isolated from each treatment into clonal cultures, and maintained at all three <italic>p</italic>CO<sub>2</sub> levels for approximately 1 year. Periodically (4, 8, and 12 months), these <italic>p</italic>CO<sub>2</sub>‐conditioned clones were recombined into artificial communities, and allowed to compete at their conditioning <italic>p</italic>CO<sub>2</sub> level or at higher and lower levels. The dominant species in these artificial communities of CO<sub>2</sub>‐conditioned clones differed from those in the original short‐term experiment, but individual species relative abundance trends across <italic>p</italic>CO<sub>2</sub> treatments were often similar. Specific growth rates showed no strong evidence for fitness increases attributable to conditioning <italic>p</italic>CO<sub>2</sub> level. Although <italic>p</italic>CO<sub>2</sub> significantly structured our experimental communities, conditioning time and biotic interactions like mixotrophy also had major roles in determining competitive outcomes. New methods of carrying out extended mixed species experiments are needed to accurately predict future long‐term phytoplankton community responses to changing <italic>p</italic>CO<sub>2</sub>.</p> </abstract>