The metazoan meiofauna in the Chukchi Sea were collected from seven shallow water stations(depths ranging 46 to 52 m) and five deep sea stations(depths ranging between 393 and 2 300 m) during the 4th Chinese National ...The metazoan meiofauna in the Chukchi Sea were collected from seven shallow water stations(depths ranging 46 to 52 m) and five deep sea stations(depths ranging between 393 and 2 300 m) during the 4th Chinese National Arctic Research Expedition in 2010. The results showed that abundance of meiofauna was higher in shallow water sediments(average of 2 445 ind./(10 cm2)) than in deep sea sediments(407.06 ind./(10 cm2)). A UNIANOVA test for difference between the two different regions was highly significant(F=101.15, p<0.01). Nematodes were numerically dominant, representing(96.6±4.6)% of the total meiofaunal abundance at the shallow water stations and(98.90±1.42)% at deep sea stations. The number of higher taxonomic groups and abundance of meiofauna were higher at Stas CC1, CC4, and R06 near the Bering Strait and the continent, than at the rest of the shallow water and deep sea stations. The primary factors causing the differences were concentrations of nutrients P and Si of bottom seawater(R=0.831, p<0.003), followed by depth(R=-0.655, p<0.05) and sand fractions of sediments(R=0.632, p <0.05). The numbers of meiofauna on the 65 μm and 32 μm sieves were significantly higher than those on the rest of the screens. Differences in numbers of meiofauna retained on screens with different mesh openings were highly significant among all sampling stations(F=31.60, p<0.01). The highest numbers of individuals on screens with 32 μm mesh openings were found at deep sea stations. The number of meiofauna in the top 0–1, 1–2, and 2–4 cm segments constituted 84.4% of the total and was significantly higher than those in the bottom 4–6 and 6–10 cm segments(F=15, p<0.01).展开更多
Diatoms collected from the top 1 cm of the surface sediment layer at seven Bering Sea stations during the Fourth Chinese National Arctic Research Expedition(4th CHINARE-Arctic)in 2010 were studied.In total,101 taxa be...Diatoms collected from the top 1 cm of the surface sediment layer at seven Bering Sea stations during the Fourth Chinese National Arctic Research Expedition(4th CHINARE-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 nordenskioeldii,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.展开更多
基金The Chinese Polar Environment Comprehensive Investigation and Assessment Programs under contract No.CHINARE2012-03-05the Ocean Public Welfare Scientific Research Project of China under contract No.201105022-2the Polar Science Strategic Research Foundation of China under contract No.20120105
文摘The metazoan meiofauna in the Chukchi Sea were collected from seven shallow water stations(depths ranging 46 to 52 m) and five deep sea stations(depths ranging between 393 and 2 300 m) during the 4th Chinese National Arctic Research Expedition in 2010. The results showed that abundance of meiofauna was higher in shallow water sediments(average of 2 445 ind./(10 cm2)) than in deep sea sediments(407.06 ind./(10 cm2)). A UNIANOVA test for difference between the two different regions was highly significant(F=101.15, p<0.01). Nematodes were numerically dominant, representing(96.6±4.6)% of the total meiofaunal abundance at the shallow water stations and(98.90±1.42)% at deep sea stations. The number of higher taxonomic groups and abundance of meiofauna were higher at Stas CC1, CC4, and R06 near the Bering Strait and the continent, than at the rest of the shallow water and deep sea stations. The primary factors causing the differences were concentrations of nutrients P and Si of bottom seawater(R=0.831, p<0.003), followed by depth(R=-0.655, p<0.05) and sand fractions of sediments(R=0.632, p <0.05). The numbers of meiofauna on the 65 μm and 32 μm sieves were significantly higher than those on the rest of the screens. Differences in numbers of meiofauna retained on screens with different mesh openings were highly significant among all sampling stations(F=31.60, p<0.01). The highest numbers of individuals on screens with 32 μm mesh openings were found at deep sea stations. The number of meiofauna in the top 0–1, 1–2, and 2–4 cm segments constituted 84.4% of the total and was significantly higher than those in the bottom 4–6 and 6–10 cm segments(F=15, p<0.01).
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)
文摘Diatoms collected from the top 1 cm of the surface sediment layer at seven Bering Sea stations during the Fourth Chinese National Arctic Research Expedition(4th CHINARE-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 nordenskioeldii,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.
