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The effects of Temperature on the Photosynthetic Parameters and Recovery of Two Temperate Benthic Microalgae, Amphora CF. Coffeaeformis and Cocconeis CF. Sublittoralis (Bacillariophyceae)
Temperature and irradiance are the most important factors affecting marine benthic microalgal photosynthetic rates in temperate intertidal areas. Two temperate benthic diatoms species, Amphora cf. coffeaeformis (C. Agardh) Ku¨tz. and Cocconeis cf. sublittoralis Hendey, were investigated to determine how their photosynthesis responded to temperatures ranging from 58C to 508C after short-term exposure (1 h) to a range of irradiance levels (0, 500, and 1,100 lmol photons Æ m)2 Æ s)1). Significant differences were observed between the temperature responses of maximum relative electron transport rate (rETRmax), photoacclimation index (Ek), photosynthetic efficiency (a), and effective quantum yield (DF ⁄ Fm’) in both species. A. coffeaeformis had a greater tolerance to higher temperatures than C. sublittoralis, with nonphotochemical quenching (NPQ) activated at temperatures of 458C and 508C. C. sublittoralis, however, demonstrated a more rapid rate of recovery at ambient temperatures. Temperatures between 108C and 208C were determined to be optimal for photosynthesis for both species. High temperatures and irradiances caused a greater decrease in DF ⁄ Fm’ values. These results suggest that the effects of temperature are species specific and that short-term exposure to adverse temperature slows the recovery process, which subsequently leads to photoinhibition.
Funding
Australian Research Council
History
Publication title
Journal of PhycologyVolume
47Issue
6Pagination
1413-1424ISSN
0022-3646Department/School
Institute for Marine and Antarctic StudiesPublisher
Blackwell Publishing IncPlace of publication
350 Main St, Malden, USA, Ma, 02148Rights statement
The definitive published version is available online at: http://www3.interscience.wiley.com/Repository Status
- Restricted