Short-term Effect of Temperature on the Photokinetics of Microalgae from the Surface Layers of Antarctic Pack Ice
Microalgae growing within brine channels (85 psu salinity) of the surface ice layers of Antarctic pack ice showed considerable photosynthetic tolerance to the extreme environmental condition. Brine microalgae exposed to temperatures above -5C and at irradiances up to 350 mol photons m -2s-1 showed n...
Published in: | Journal of Phycology |
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Main Authors: | , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Blackwell Publishing
2005
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Subjects: | |
Online Access: | https://doi.org/10.1111/j.1529-8817.2005.00106.x http://ecite.utas.edu.au/38123 |
Summary: | Microalgae growing within brine channels (85 psu salinity) of the surface ice layers of Antarctic pack ice showed considerable photosynthetic tolerance to the extreme environmental condition. Brine microalgae exposed to temperatures above -5C and at irradiances up to 350 mol photons m -2s-1 showed no photosynthetic damage or limitations. Photosynthesis was limited (but not photoinhibited) when brine microalgae were exposed to -10C, provided the irradiance remained under 50 mol photonsm-2s-1. The highest level of photosynthetic activity (maximum relative electron transport rate [rETR max]) in brine microalgae growing within the surface layer of sea ice was at approximately 18 mol electronsm-2s -1, which occurred at -1.8 C. Effective quantum yield of PSII and rETRmax of the halotolerant brine microalgae exhibited a temperature-dependent pattern, where both parameters were higher at -1.8 C and lower at -10 C. Relative ETRmax at temperatures above -5C were stable across a wide range of irradiance. 2005 Phycological Society of America. |
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