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通过对菲律宾南部MD06-3075和婆罗洲东北部MD98-2178两个深海钻孔的孢粉分析,结合氧同位素记录以及西太平洋地区已有的孢粉记录,得到末次冰期研究区域海洋孢粉中的红树林花粉和蕨类孢子含量比间冰期时要低,特别是在末次冰盛期。这可能体现了冰期时海平面较低,湿度较低等环境和气候条件。同时,西太平洋一系列海洋孢粉记录的对比发现,南海南部陆坡地区冰期时的红树林含量仍然较高,巽他陆架等地区冰期时的蕨类孢子含量则表现为明显高值。这些记录的差异可能说明了由于不同地区的地形分布特征不同,在冰期海平面下降时,导致陆架出露的幅度存在明显的差异。如果陆架较宽,则海平面波动会显著改变植被分布范围和孢粉传播距离等,从而对孢粉数据的气候、环境指示意义产生影响。因此,海洋孢粉数据解释时需要结合多种沉积记录指标以及地球物理调查等,提高海平面变化以及相应的沉积环境演化对孢粉搬运沉积的了解程度,增强海洋孢粉中古气候、古环境信息的有效提取。
Based on the sporo-pollen analysis of two deep-sea boreholes from MD06-3075 in the southern part of the Philippines and MD98-2178 in the northeast of Borneo, and combining with the records of oxygen isotopes and the existing records of sporopollen in the western Pacific, Mangrove pollen and fern spores were lower in the interglacials, especially during the last glacial expanse. This may reflect the environmental and climatic conditions during the glacial period such as lower sea level and lower humidity. Meanwhile, a series of records of marine sporopollen in the western Pacific Ocean show that the mangrove content in the southern South China Sea is still high during the glacial period, and the fern spore content in the ice shelf of the Stena shelf shows a significant high value. The differences in these records may indicate that there is a clear difference in the magnitude of continental shelf exposure caused by the declining sea level during the ice age due to the different terrain distribution characteristics in different regions. If the shelf is wider, the sea level fluctuation will significantly change the vegetation distribution range and sporopollen propagation distance, which will influence the climatic and environmental significance of the sporopollen data. Therefore, marine pollen data interpretation needs a combination of various sedimentary records and geophysical surveys to improve the understanding of sea level changes and the corresponding evolution of depositional environment for the deposition and transport of pollen, and to enhance the paleoclimate and paleoenvironmental information of marine pollen Effective extraction.