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为解决近1000年以来东海沿岸地区气候演化及其对南冲绳海槽陆源物质输入的影响,对取自南冲绳海槽的MD05-2908孔上部(0～810cm)共78份孢粉样品和199份有机碳同位素样品进行了分析.结果显示,近1000年以来南冲绳海槽陆源物质输入存在着显著波动,其中1100～1040aBP、960～880aBP和800～480aBP期间,陆源物质输入比例增加;1040～960aBP和480～230aBP期间,陆源物质输入比例减少.将陆源物质输入指标与陕西佛爷洞δ13C含量记录对比分析,发现陆源物质输入比例变化与季风的变化密切相关.当夏季风减弱时,导致降雨带长时间集中在南部地区,增强的降雨量提高了风化剥蚀以及沉积物向海洋搬运的能力,使得陆源物质供应量增加.
In order to solve the climatic evolution in the East China Sea coast and its contribution to the terrestrial material input in the South Okinawa Trough over the past 1,000 years, a total of 78 sporopollen samples from the upper part (0 ~ 810 cm) of MD05-2908 collected from the South Okinawa Trough and 199 Organic carbon isotope samples were analyzed.The results showed that there was a significant fluctuation of terrigenous inputs in the South Okinawa Trough over the past 1000 years, of which, the input proportion of terrestrial sources increased during 1100 ~ 1040aBP, 960 ~ 880aBP and 800 ~ 480aBP, while that of 1040 ~ 960aBP and 480 ~ 230aBP, the input ratio of terrestrial material decreased.Comparing the input data of terrestrial material with the δ13C content of Fuyong Cave in Shaanxi Province, it was found that the change of terrestrial input was closely related to the change of monsoon input.When the summer monsoon weakened, For a long time concentrated in the southern region, increased rainfall increased the ability of weathered and denudated sediments to be transported to the sea, resulting in an increase in the supply of terrestrial supplies.