Photosynthetic nature of ice-algae under fast ice near Syowa Station, Antarctica

• Main Authors: Hiroo Satoh, Kentaro Watanabe
• Format: Report
• Language: English
• Published: Tokyo University of Fisheries 1986
• Subjects: Antarctic; Syowa Station; Antarc*; Antarctica; E. Antarctica; ice algae; Memoirs of National Institute of Polar Research; Polar Research; Sea ice
• Online Access: https://nipr.repo.nii.ac.jp/?action=repository_uri&item_id=2030; http://id.nii.ac.jp/1291/00002030/; https://nipr.repo.nii.ac.jp/?action=repository_action_common_download&item_id=2030&item_no=1&attribute_id=18&file_no=1

The photosynthetic nature of the ice-associated microalgal assemblages (ice-algae) was investigated in the annual sea ice area near Syowa Station (69°00′S, 39°35′E), Antarctica. The maximum photosynthetic rate of 1.23mgO_2/mg chl. α/h was obtained under the light intensity of 25μE/m^2/s. In a higher light condition above 80μE/m^2/s, a depression of the rate caused by photo-inhibition was observed. These results demonstrated the low-light-adaptation of Antarctic ice-algae under the exceedingly low light conditions. The light condition under the ice was largely controlled by the thickness of snow covering the fast ice as well as by the variation of solar radiation. The optimum temperature for photosynthesis of the ice-algae was about 8℃, while the rates of photosynthesis reduced at higher temperatures. In the present area, an average specific growth rate (μ) of the ice-algae was 0.25 div./day.