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通过对中国首次和第二次北极科学考察在北冰洋西部所采取的66个表层沉积物中生源组分的分析,探讨了该海区表层生产力变化与水团的相互关系。楚科奇海西南部呈现出高的有机碳和生源蛋白石含量,而中部和东部哈罗德浅滩至阿拉斯加沿岸,以及楚科奇海台、北风脊和加拿大海盆表现出低的有机碳和生源蛋白石含量。楚科奇海陆架区表层沉积物以底栖有孔虫为主,丰度低;而楚科奇海台、北风脊和加拿大海盆则以浮游有孔虫占绝对优势,丰度较高。生源组分的分布特征显然与通过白令海峡进入楚科奇海的三股太平洋水和大西洋次表层水相关。楚科奇海西侧沿富营养的阿纳德尔流方向的区域呈现出高的表层生产力。而东侧受寡营养的阿拉斯加沿岸流及阿拉斯加西北沿岸陆源物质输入的影响,呈现出低的表层生产力。北纬75°以北及加拿大海盆受海冰覆盖影响,也表现出最低的表层生产力。而受北大西洋次表层水的影响,楚科奇海陆架外侧高纬海域表现出较高的钙质生物生产力。表层沉积物中Corg/N比值及其分布反映楚科奇海表层沉积物中的有机碳以海洋自身来源为主,且主要受生物泵过程控制。有机碳和生源蛋白石含量呈现高的正相关关系,说明硅藻等浮游植物的初级生产力可能控制着生物泵对碳的吸收和释放。
Based on the analysis of the source components of 66 surface sediments taken by the first and second Arctic scientific expeditions in the western Arctic Ocean, the relationship between surface water productivity and the water mass was discussed. High levels of organic carbon and biogenic opal are present in the southwestern part of the Chukchi Sea while low and organic carbon and biogenic sources are found in the shores of Harold Foothills to the Alaskan Shores in the Central and East, and in the Chukothai, Northwind Ridges and Canadian Seabeds Opal content. The surface sediments in the Chukchi Sea shelf area are mainly benthic foraminifera with low abundance. However, the planktonic foraminifera in the Chukchi Sea platform, the north wind ridge and the Canadian basin account for the absolute superiority and abundance. The distribution of the biogenic components apparently correlates with the three Pacific and Atlantic sub-surface waters entering the Chukchi Sea through the Bering Strait. The area along the nutritious Anadyr flow shows a high surface productivity on the western side of the Chukchi Sea. On the eastern side of the Alaskan littoral and the input of terrestrial sources in the northwestern Alaska coast, there is low surface productivity. North of 75 ° north latitude and the Canadian basin affected by sea ice, also showed the lowest surface productivity. Affected by the sub-surface water in the North Atlantic Ocean, the high-latitude waters outside the shelf of the Chukchi Sea show higher productivity of calcareous organisms. The Corg / N ratio and its distribution in the surface sediments reflect that the organic carbon in the surface sediments of the Chukchi Sea is dominated by the ocean itself and is mainly controlled by the biological pump process. There is a high positive correlation between organic carbon and biogenic opal content, indicating that the primary productivity of phytoplankton such as diatoms may control the absorption and release of carbon by biological pumps.