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在冲绳海槽北部B-3GC孔高分辨率地层年代框架的基础上,利用多种分子生物标志物和生源组分指标,重建了该地区全新世以来表层海水温度和生产力的变化历史。研究发现,UK3′7—表层海水温度和生产力的变化指示了全新世黑潮及对马暖流分支的变迁。10.6～7.3 ka BP期间,冲绳海槽北部主要受东海陆架冷水团影响,陆源物质输入量增加,初级生产力比较高,表层海水温度较低。7.3～4.6 ka BP期间,黑潮暖流对该区的影响迅速增强,表层海水快速增温,陆源物质输入减少,但是各种生产力指标显示出上升趋势,与该区上升流的出现和迅速发育有关。4.6～2.7 ka BP期间,即全新世普林虫低值事件(PME)期间,表层海水温度明显降低了0.8～1.4℃,陆源物质输入增加,初级生产力和各种生源组分的含量也达到较高水平,说明此时黑潮强度减弱,或者黑潮主流轴向太平洋方向发生偏移,该区再次受到陆架冲淡水的影响。2.7 ka BP以来,虽然黑潮暖流再次影响到该海区,但初级生产力和生源物质输出量继续大幅增高,可能与该地区上升流的持续发育有关。
On the basis of the B-3GC pore-age high-resolution stratigraphic framework in the northern Okinawa Trough, a series of molecular biomarkers and biogenic components were used to reconstruct the history of surface sea temperature and productivity changes since the Holocene. The study found that the changes in UK3’7-surface sea temperature and productivity indicate the Holocene Kuroshio and the change of the warm-current branches of the Ma. During the period from 10.6 to 7.3 ka BP, the northern Okinawa Trough was mainly affected by the cold water mass of the East China Sea continental shelf. The input of terrestrial materials increased, the primary productivity was relatively high, and the surface sea water temperature was relatively low. During the period from 7.3 to 4.6 ka BP, the Kuroshio current increased rapidly in this area, the surface seawater rapidly increased and the input of terrestrial materials decreased. However, all kinds of productivity indicators showed an upward trend, which was related to the emergence and rapid development of upwelling in this area . During 4.6-2.7 ka BP, during the Holocene Ephemeral Preservalence (PME) period, the surface seawater temperature decreased significantly by 0.8-1.4 ℃. The input of terrigenous materials increased, and the primary productivity and the content of various biogenic components also reached a relatively high level The high level indicates that the intensity of the Kuroshio was weakened at this time or that the mainstream of the Kuroshio was offset in the direction of the axial Pacific Ocean and that the area was once again affected by the freshwater flushing on the shelf. Since 2.7 ka BP, although the Kuroshio current once again affected the sea area, the output of primary productivity and biogenic materials continued to increase significantly, which may be related to the sustained development of the upwelling in the area.