Biogeochemical Variation in Dimethylsulfide, Phytoplankton Pigments and Heterotrophic Bacterial Production in the Subarctic North Pacific during Summer |
| |
| Authors: | Kazushi Aranami Shuichi Watanabe Shizuo Tsunogai Masato Hayashi Ken Furuya and Toshi Nagata |
| |
| Institution: | (1) Laboratory of Marine and Atmospheric Geochemistry, Graduate School of Environmental Earth Science, Hokkaido University, Sapporo, 060-0810, Japan;(2) Depertment of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi, Bunkyo, Tokyo, 113-8657, Japan;(3) Ocean Research Institute, The University of Tokyo, Minami-dai, Nakano, Tokyo, 164-8639, Japan |
| |
| Abstract: | Dimethylsulfide (DMS), chlorophyll a (Chl-a), accessory pigments (fucoxanthin, peridinin and 19 -hexanoyloxyfucoxanthin), and bacterial production (BP) were measured in the surface layer (0–100 m) of the subarctic North Pacific, including the Bering Sea, during summer (14 July–5 September, 1997). In surface sewater, the concentrations of DMS and Chl-a varied widely from 1.3 to 13.2 nM (5.1 ± 3.0 nM, mean ± S.D., n = 48) and from 0.1 to 2.4 µg L–1 (0.6 ± 0.6 µg L–1, n = 24), respectively. In the subarctic North Pacific, DMS to Chl-a ratios (DMS/Chl-a) were higher on the eastern side than the western side (p < 0.0001). Below the euphotic zone, DMS/Chl-a ratios were law and the correlation between DMS and Chl-a was relatively strong (r
2 = 0.700, n = 27, p < 0.0001). In the euphotic zone, DMS/Chl-a ratios were higher and the correlation between DMS and Chl-a was weak (r
2 = 0.128, n = 50, p = 0.01). The wide variation in DMS/Chl-a ratios would be at least partially explained by the geographic variation in the taxonomic composition of phytoplankton, because of the negative correlation between DMS/Chl-a and fucoxanthin-to-Chl-a ratios (Fuc/Chl-a) (r
2 = 0.476, n = 26, p = 0.0001). Furthermore, there was a positive correlation between DMS and BP (r
2 = 0.380, n = 19, p = 0.005). This suggests that BP did not represent DMS and dimethylsulfoniopropionate (DMSP) removal by bacterial consumption but rather DMSP degradation to DMS by bacterial enzyme. |
| |
| Keywords: | Dimethylsulfide to chlorophyll a ratio (DMS/Chl-a) fucoxanthin to chlorophyll a ratio (Fuc/Chl-a) bacterial production (BP) |
| 本文献已被 SpringerLink 等数据库收录！ |
|
