中文摘要：

日本海南部郁陵海盆的UB-2孔沉积物硅藻记录,反映了11000—28000aBP该区古海洋和古气候的变化。对比日本海和格陵兰冰芯（GRIP）^δ18O数据,UB-2孔硅藻暖水种比率及淡水—海滨种含量变化清楚地记录了氧同位素3期（MIS3）、末次盛冰期（LGM）、波令—阿勒罗德暖期（B/A）以及新仙女木冷事件（YD）等古气候事件。淡水—海滨种硅藻含量在末次盛冰期阶段明显升高及暖水种数量的显著减少,表明此时日本海为低温、低盐的古海洋环境,这可归因于气候变冷、海平面下降造成的日本海当时相对封闭的海洋环境。自15200aBP起,Paraliasulcata含量逐渐上升,这可能与海平面上升引起的古环境变化有关,可以作为对马海峡开启的标志。全球气候变化引起的海平面变化是该区域古气候变化的主要控制因素。

英文摘要：

A diatom record of core UB-2 from the Ulleung Basin in the southern part of Japan Sea reveals palaeoenvironmental changes through 11 000—28 000 {a BP}.Comparing with the δ18O records of Japan Sea and the Greenland icecore Project（GRIP）,the Marine Isotope Stages 3（MIS3）,the Last Glacial Maximum（LGM）,the Blling-Allerd warm phase（B/A）and the Younger Dryas cold event（YD）are clearly distinguished by the changes in percentage of warm water species and in abundance of fresh-littoral species.High abundance of fresh-littoral species during the LGM conforms a low temperature and low salinity palaeoceanographical environment due to the closed marine environment.Raising of the sea-level resulted in high abundance of Paralia sulcata from 15 200 {a BP},which refers to the opening of the Tsushima Strait.Climate-induced palaeogeographic variations may be the main contributor to the palaeoenvironmental changes.