Diatoms from surface sediment samples in the Bering and Chukchi seas were analyzed to reveal the distribution patterns and their relationship with the ocean environment. A low abundance was found to the north of the A...Diatoms from surface sediment samples in the Bering and Chukchi seas were analyzed to reveal the distribution patterns and their relationship with the ocean environment. A low abundance was found to the north of the Arctic Sea ice Minimum （ASIMin）, indicating that diatom growth is strongly inhibited by perennial sea ice. Between the ASIMin and the Arctic Sea Ice Maximum （ASIMax） which experiences seasonal sea ice, the sea ice related diatoms （mainly Fragilariopsis oceanica and Fragi- lariopsis cylindrus） were dominant, thereby confirming that sea ice is an important influencing factor. The Chaetoceros resting spores were more abundant in the Chukchi Sea, which corresponds well with the active phytoplankton distribution in the water column, and is possibly attributed to the stronger hydrodynamic conditions present in the Bering Sea. The abundances of Chaeto- ceros resting spores were the lowest on the northeast Bering Shelf, possibly because of lower water depth, stronger coastal cur- rents, river influx, coarser particle sizes and stronger winds and bottom currents. The Arctic Diatom Group （dominated by Bac- terosira bathyomphala, Thalassiosira antarctica v. borealis and Thalassiosira antarctica resting spores） was more abundant in the Bering Basin and the areas central of and to the north of Chukchi Plateau, while the Coastal Benthic Diatoms （including Paralia sulcata and Delphineis surirella） were mainly found on the northeast Bering Shelf and nearby Cape Lisburne in the Chukchi Sea. Thalassiosira nordenskioeldii was found to be the most abundant around the Bering Strait, while Neodenticula seminae was only found in the Bering Sea and mainly distributed in the Bering Basin, indicating its close correlation with the Pacific waters展开更多
Based on a quantitative analysis of foraminifera in 39 surface samples of the Bering andChukchi Seas, the nearly absence of planktonic foraminifera in the surface sediments can be related to the low surface primary pr...Based on a quantitative analysis of foraminifera in 39 surface samples of the Bering andChukchi Seas, the nearly absence of planktonic foraminifera in the surface sediments can be related to the low surface primary productivity and strong carbonate dissolution in the study area. It has been revealed that the surface primary productivity, and carbonate dissolution and properties of water masses related to the water depth mainly control the distribution of benthic foraminifera. The shelf of the Chukchi Sea is dominated by the Elphidium spp. assemblage and Nonionella robusta assemblage with low foraminiferal abundance and diversity, which is controlled by the coastal water mass of the Arctic Ocean. The slope of the Bering Sea is dominated by the Uvigerina peregrina - Globobulimina affinis assemblage with abundant N. robusta, and relatively high foraminiferal abundance and diversity, which is controlled by the intermediate and deep water masses of the Pacific Ocean. However, the Bering Sea has relatively shallow carbonate lysocline and compensation depth (CCD) , at about 2 000 and 3 800 m, respectively. In addition, there exists Stetsonia arctica in the surface sediments of the upper slope in the Bering Sea, which is a typical deep-sea benthic foraminiferal species of the slope in the Arctic Ocean. This indicates that the deep water of the two seas beside the Bering Strait had ever exchanged.展开更多
Iodine is an important trace element associated closely with human being, and it will influence human’s normal growth if lacking it. Meanwhile, iodine is an important catalyzer, and is important in atmospheric chemis...Iodine is an important trace element associated closely with human being, and it will influence human’s normal growth if lacking it. Meanwhile, iodine is an important catalyzer, and is important in atmospheric chemistry study. In nature, iodine is rich mainly in marine organism and sediment, and marine sediment has the largest storage of iodine. The analysis results of sediment samples obtained by the First Chinese National Arctic Research Expedition indicate that iodine contents in sediments in the Chukchi Sea and the Bering Sea are 98.1x10-6 and 73.8x10-6, respec-tively, which are higher than those in sediments of Chinese marginal seas and the southern Pacific Ocean, and show the trend of increase from low latitude to high latitude. This paper proposes a pattern of iodine latitudinal distribution on the basis of the distribution characteristic of iodine and its enrichment mechanism in sediments of the Chukchi Sea and the Bering Sea.展开更多
基金Financial support from the SOA Key Laboratory of Polar Science,(Grant no.KP2008003)the Basic Research Foundation of the Second Institute of Oceanography,SOA (Grant no.JG0908)+1 种基金the National Natural Science Foundation of China (Grant nos.41076135,41003036)the Polar Strategy Foundation of China (Grant no.20080213) are highly appreciated for facilitating this work
文摘Diatoms from surface sediment samples in the Bering and Chukchi seas were analyzed to reveal the distribution patterns and their relationship with the ocean environment. A low abundance was found to the north of the Arctic Sea ice Minimum （ASIMin）, indicating that diatom growth is strongly inhibited by perennial sea ice. Between the ASIMin and the Arctic Sea Ice Maximum （ASIMax） which experiences seasonal sea ice, the sea ice related diatoms （mainly Fragilariopsis oceanica and Fragi- lariopsis cylindrus） were dominant, thereby confirming that sea ice is an important influencing factor. The Chaetoceros resting spores were more abundant in the Chukchi Sea, which corresponds well with the active phytoplankton distribution in the water column, and is possibly attributed to the stronger hydrodynamic conditions present in the Bering Sea. The abundances of Chaeto- ceros resting spores were the lowest on the northeast Bering Shelf, possibly because of lower water depth, stronger coastal cur- rents, river influx, coarser particle sizes and stronger winds and bottom currents. The Arctic Diatom Group （dominated by Bac- terosira bathyomphala, Thalassiosira antarctica v. borealis and Thalassiosira antarctica resting spores） was more abundant in the Bering Basin and the areas central of and to the north of Chukchi Plateau, while the Coastal Benthic Diatoms （including Paralia sulcata and Delphineis surirella） were mainly found on the northeast Bering Shelf and nearby Cape Lisburne in the Chukchi Sea. Thalassiosira nordenskioeldii was found to be the most abundant around the Bering Strait, while Neodenticula seminae was only found in the Bering Sea and mainly distributed in the Bering Basin, indicating its close correlation with the Pacific waters
基金This study was supported by the Scientific Project of the First Chinese Marine (Geological Expedition to the North Pole the Opening Fund of the Key Laboratory of Submarine Geosciences, State Oceanic Administration.
文摘Based on a quantitative analysis of foraminifera in 39 surface samples of the Bering andChukchi Seas, the nearly absence of planktonic foraminifera in the surface sediments can be related to the low surface primary productivity and strong carbonate dissolution in the study area. It has been revealed that the surface primary productivity, and carbonate dissolution and properties of water masses related to the water depth mainly control the distribution of benthic foraminifera. The shelf of the Chukchi Sea is dominated by the Elphidium spp. assemblage and Nonionella robusta assemblage with low foraminiferal abundance and diversity, which is controlled by the coastal water mass of the Arctic Ocean. The slope of the Bering Sea is dominated by the Uvigerina peregrina - Globobulimina affinis assemblage with abundant N. robusta, and relatively high foraminiferal abundance and diversity, which is controlled by the intermediate and deep water masses of the Pacific Ocean. However, the Bering Sea has relatively shallow carbonate lysocline and compensation depth (CCD) , at about 2 000 and 3 800 m, respectively. In addition, there exists Stetsonia arctica in the surface sediments of the upper slope in the Bering Sea, which is a typical deep-sea benthic foraminiferal species of the slope in the Arctic Ocean. This indicates that the deep water of the two seas beside the Bering Strait had ever exchanged.
基金This work was supported by the National Natural Science Foundation of China (Grant Nos. 49873015 40176017) and the Special Foundation for the First Chinese National Arctic Research Expedition.
文摘Iodine is an important trace element associated closely with human being, and it will influence human’s normal growth if lacking it. Meanwhile, iodine is an important catalyzer, and is important in atmospheric chemistry study. In nature, iodine is rich mainly in marine organism and sediment, and marine sediment has the largest storage of iodine. The analysis results of sediment samples obtained by the First Chinese National Arctic Research Expedition indicate that iodine contents in sediments in the Chukchi Sea and the Bering Sea are 98.1x10-6 and 73.8x10-6, respec-tively, which are higher than those in sediments of Chinese marginal seas and the southern Pacific Ocean, and show the trend of increase from low latitude to high latitude. This paper proposes a pattern of iodine latitudinal distribution on the basis of the distribution characteristic of iodine and its enrichment mechanism in sediments of the Chukchi Sea and the Bering Sea.
