Photosynthetic nature of ice algae and their contribution to the primary production in lagoon Saroma Ko, Hokkaido, Japan
Photosynthetic activity of ice algae and phytoplankton was investigated under sea ice at two stations (ca. 44°10'N, 143°46'E) in lagoon Saroma Ko, Hokkaido, Japan, in early March 1987. Water temperature and salinity ranged from -1.1 to -1.4℃ and from 32.4 to 33.5, respectively. The maximum...
Main Authors: | , , , , , |
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Format: | Report |
Language: | English |
Published: |
Tokyo University of Fisheries/Laboratory of Biology, College of Liberal Arts, Saitama University/National Institute of Polar Research/National Institute of Polar Research/National Institute of Polar Research/Tokyo University of Fisheries
1989
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Subjects: | |
Online Access: | https://nipr.repo.nii.ac.jp/?action=repository_uri&item_id=5043 http://id.nii.ac.jp/1291/00005043/ https://nipr.repo.nii.ac.jp/?action=repository_action_common_download&item_id=5043&item_no=1&attribute_id=18&file_no=1 |
Summary: | Photosynthetic activity of ice algae and phytoplankton was investigated under sea ice at two stations (ca. 44°10'N, 143°46'E) in lagoon Saroma Ko, Hokkaido, Japan, in early March 1987. Water temperature and salinity ranged from -1.1 to -1.4℃ and from 32.4 to 33.5, respectively. The maximum chlorophyll a concentrations of ice algae within 4cm from the bottom of sea ice and phytoplankton in water column were 385 and 0.77 mg m^<-3>, respectively. The maximum photosynthetic rate (1.12 mgO_2 mgchl, a^<-1> h^<-1>) of ice algae was obtained under 37.5 μEm^2 s^<-1>, which corresponds to only 3% of incident solar radiation. These results demonstrate the low-light adaptation of ice algae grown under low light conditions. The optimum temperature for photosynthesis of ice algae was around 8℃. In situ measurements on a clear day gave the primary production of 1.59 mgCm^<-2> h^<-1> by ice algae and that of 1.92 mgCm^<-2> h^<-1> by phytoplankton. It was concluded that the ice algae contribute to a considerable extent to the production of organic carbon in the ice-covered area of Saroma Ko during winter. |
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