东亚地区MIS 5时期孢粉记录的植被与气候研究进展

末次间冰期(深海氧同位素5阶段,MIS 5,71~128 ka BP)离现代间冰期最近,对其认识有助于预测未来环境,而化石孢粉是恢复古植被与古气候的重要指标。通过对选择出的东亚地区孢粉记录的具有年代数据和孢粉图谱的古植被和气候研究的综合分析,初步认为:①MIS 5的植被格局可与现代间冰期即全新世的植被格局对比。②各区孢粉记录了MIS 5气候波动,部分地区可划分出5a,5b,5c,5d和5e,存在轨道尺度变化,千年尺度事件较少发现。③东亚季风是影响现代东亚季风区环境的主要因素,但日本可能还受到西风环流和洋流的影响;西风、印度季风和地形是影响青藏高原环境的主要因素。④东亚地区,特别是干旱半干旱区,分辨率较高的孢粉记录的环境变化仍需更深入的研究。

Vegetation and Climate Inferred from Pollen Record in East Asian Region During MIS 5:A Review

The last interglacial,Marine Isotope Stage 5(MIS 5,about 71~128 ka BP),is the closest to modern interglacial period,in which there are identifiable patterns that could give us clues into what will happen in the future. Pollen analysis,the study of fossil pollen and spores,is one of the key methods for the reconstruction of past vegetation and environment. Pollen data from 23 sites in eastern Asian region were reviewed to document regional patterns of vegetation and climate change during MIS 5 and to understand the large-scale controls on these changes. The regional patterns of vegetation during MIS 5 can be compared with the present-day vegetation. The climate,inferred from pollen record,was not stable during MIS 5. The substages(5 a,5 b,5 c,5 d and 5 e)of MIS 5 can be identified by pollen assemblages in some areas,which describe the imprint of orbital-scale climate oscillations. East Asian monsoons have significantly contributed to the environment of modern eastern Asian monsoon region during MIS 5. However,the climate in Japan is also affected by the ocean currents and westerly circulation. The climate of the Tibetan Plateau is controlled by interactions of competing factors,including Indian monsoons,westerlies,and topography. In eastern Asian region,particularly in arid and semi-arid regions,the high-resolution pollen records need to be further studied for the better understanding of the climate change.