利用高分辨率海洋孢粉记录重建氧同位素3期以来南海北部的陆地气候

深海氧同位素3期（MIS3）（大约60cal.ka BP）以来的地球气候经历了陆地冰盖逐渐增大，然后消融的过程，对这一过程的认识可以帮助我们理解全球气候变化的动力机制。在南海北部的深海沉积物中保存了来自周边陆地的花粉与孢子化石（简称孢粉），它们记录了周边陆地的植被与气候历史。长期以来，古气候学家对于南海北部氧同位素3期以来，特别是末次盛冰期时的陆地气候状态的重建还存在争议，这影响了对南海甚至东亚地区古环境变化机制的深入理解。问题的关键是我们对孢粉粒从母本植物到沉积至深海这一传播过程了解的匮乏。本课题计划在现代孢粉传播与沉积机制研究的基础上选取位于南海北部大陆坡高速沉积体上的MD05-2906钻孔进行孢粉分析，目的在于重建氧同位素3期以来南海北部陆地植被与气候,以及展示古季风变化同岁差周期间的关系。

Global climate experienced strong variations since the marine isotope stage 3(MIS3)(about 60 cal.ka BP),which included enhanced continental ice sheet and later collapse,how to understand climate change process in this stage that is important to confirm forcing mechanism of climate change.Pollen and spores grains derived from adjacent land were preserved in the marine sediments that record vegetation and climate history in surrounding land.Continental climate conditions since the MIS3, especially during the Last Glacial Maximum (LGM) in the northern SCS have been argued all the time, which limited our further understanding forcing mechanisms of paleoclimate variation in the SCS and East Asia.Here, the key question is little knowing for the pollen transportation and deposition processes from land to deep sea. Therefore, this project aims to reconstruct continental paleovegetation and paleoclimate since the MIS3, as well as show the relationship between paleomonsoon and precession cycle by analysis pollen fossil from drilling core MD05-2906 with high sedimentation rate located on the continental slope of the northern SCS. This research should be based on the survey of modern pollen transport and sediment processes on the marine environment.