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对白令海B5-4岩心沉积物中有机碳、CaCO3及17种地球化学元素进行分析,结合AMS14C年龄数据,恢复了白令海13.7ka以来古环境和古生产力的演化历史.结果显示,B5-4孔沉积速率高达34.2cm/ka,新仙女木(YD)、Bolling-Allerod(BA)及冰川融水信号在B5-4孔都有记录.白令海陆源沉积物的输入受源区气候、海平面变化和生源物质稀释等多种因素的控制.末次冰消期白令海以高生产力和底层水体缺氧为显著特征.冰川融水及太平洋暖水团输入是导致末次冰消期白令海高生产力的2个主要因素.末次冰消期底层水体缺氧与表层高生产力和次表层水体层化有显著的关系.但是,太平洋中层水通风能力及太平洋底层环流减弱也是导致底层水体出现缺氧现象的潜在因素.全新世,阿拉斯加环流成为白令海古生产力和古环境变化的主要控制因素,生产力及古环境在全新世没有发生显著的变化.
The analysis of organic carbon, CaCO3 and 17 kinds of geochemical elements in the B5-4 core sediments of the Bering Sea, combined with the AMS14C age data, restored the paleoenvironment and the evolution of paleoproductivity since 13.7 ka in the Bering Sea.The results show that B5-4 pores Sedimentation rate was up to 34.2cm / ka, YD, Bolling-Allerod (BA) and glacial melt signals were recorded in B5-4.The input of terrestrial sediments from the Bering Sea was affected by climate, sea level Changes and the dilution of raw materials and other factors control the last ice-off Bering Sea high productivity and the underlying water hypoxia is characterized by glacial meltwater and the Pacific warm water mass input is leading to the last ice-off Bering Sea high productivity of 2 The main factor is the lack of oxygen in the bottom water during the last ice expulsion, which has a significant relationship with high productivity and subsurface water stratification.However, the mid-level water ventilation in the Pacific Ocean and the weakened circulation in the bottom of the Pacific Ocean are also potential factors leading to hypoxia in the bottom water. During the Holocene and Alaska, the circulation became the main controlling factor of the ancient productivity and paleoenvironment in the Bering Sea. The productivity and the paleoenvironment did not change significantly during the Holocene.