摘要
Diatoms collected from the top 1 cm of the surface sediment layer at seven Bering Sea stations during the Fourth Chi- nese National Arctic Research Expedition （4th CH1NARE-Arctic） in 2010 were studied. In total, 101 taxa belonging to 38 genera were found. The species were divided into four groups： eurythermal species, boreal-temperate species, polar species, and sea-ice species. The diatom assemblages at the stations in the southwestern basin area were primarily composed of boreal-temperate species, such as Neodenticula seminae, Thalassiosira trifulta, Rhizosolenia hebetata f. hiemalis, and Actinocyclus curvatulus. The northeastern shelf stations were dominated by polar species, including Fragilariopsis oceanica, Thalassiosira antarctica spora, Thalassiosira nordensldoeldii, and Thalassiosira hyalina. The overall abundance was highest at the basin stations with 3.7 ×10^6 cells·g^-1 of wet sediment, whereas the eastern shelf stations had the lowest abundance of 0.7×10^6 cells·g^-1 of wet sediment （excluding the resting spores of Chaetoceros spp.）. The relationship between the distribution of the surface sediment diatom assemblages and the environment is discussed.
Diatoms collected from the top 1 cm of the surface sediment layer at seven Bering Sea stations during the Fourth Chi- nese National Arctic Research Expedition （4th CH1NARE-Arctic） in 2010 were studied. In total, 101 taxa belonging to 38 genera were found. The species were divided into four groups： eurythermal species, boreal-temperate species, polar species, and sea-ice species. The diatom assemblages at the stations in the southwestern basin area were primarily composed of boreal-temperate species, such as Neodenticula seminae, Thalassiosira trifulta, Rhizosolenia hebetata f. hiemalis, and Actinocyclus curvatulus. The northeastern shelf stations were dominated by polar species, including Fragilariopsis oceanica, Thalassiosira antarctica spora, Thalassiosira nordensldoeldii, and Thalassiosira hyalina. The overall abundance was highest at the basin stations with 3.7 ×10^6 cells·g^-1 of wet sediment, whereas the eastern shelf stations had the lowest abundance of 0.7×10^6 cells·g^-1 of wet sediment （excluding the resting spores of Chaetoceros spp.）. The relationship between the distribution of the surface sediment diatom assemblages and the environment is discussed.
基金
supported by the Chinese Polar Environment Comprehensive Investigation and Assessment Programmes(Grant no.CHINARE2012-03-05)
the Ocean Public Welfare Scientific Research Project of China(Grant no.201105022-2)
the Polar Science Strategic Research Foundation of China(Grant no.20120105)
