孤山屯沼泽地晚更新世以来气候演化的植硅体记录

The paleoclimate evolution recorded by phytolith in Gushantun peatland since the Late Pleistocene

东北地区泥炭以其特有的沉积学特征吸引了诸多全新世古气候研究的开展.通过选取长白山西麓孤山屯沼泽地晚更新世以来的泥炭沉积进行植硅体分析,划分出了5个植硅体组合带:Ⅰ棒型-尖型组合带,Ⅱ棒型-方型-尖型组合带,Ⅲ哑铃型-方型-鞍型组合带,Ⅳ齿型-哑铃型组合带,Ⅴ齿型-哑铃型-帽型组合带,分别代表5个不同的气候演化时期.结合植硅体温暖指数变化特征恢复了该地区自晚更新世以来的环境演化特征,揭示了晚冰期气候的振荡性与复杂性特征,较准确地识别出了相关气候阶段及气候波动事件.通过与哈尼泥炭纤维素δ18 O曲线及北大西洋深海沉积物记录的浮冰碎屑事件对比,证明了植硅体记录气候的6次冷事件与全球其他区域较为一致,为全面、客观地恢复全新世东北地区的古气候、古植被提供了参考资料.

Researches on Holocene climate have been developed based on the peat in Northeast China. And a main reason for this is the sedimentary characteristics of the peat in Changbai Mountain region are special. A peat core in Gushantun Peatland, the southwest foothill of Changbai Mountain is collected and then we divided the phytolith assembles into five zones after a series of analyses. The first combination is elongate and lanceolate shaped. The second, elongate, square and lanceolate shaped,the third, Bilobate short cell, square and Saddle, the fourth, crenate and Saddle, the last, the crenate shaped,Saddle and Rondel. These combinations represent five stages of the evolution progress of paleo-climate. In addition,the warm index curve calculated from different types of phytoliths can be used to substitute the paleo-temperature since Late Pleistocene. The warm index curve reveals the oscillation and complexity of climate and also identifies the climatic stages and climatic events. Contrasted with ~x80 curve and the Ice Rafting Detritus events in abyssal sediments,the results show that the trends of the curves in different regions of the world are in same. In conclude, the climate change information recorded by phytolith since Late Pleistocene can response well to the global climate change,in Northeast China. And this study will also provide more comprehensive and objective referable data for the reconstruction of paleo-climate and paleo-vegetation in this region.