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黄土高原风尘红黏土序列是我国晚中新世-上新世重要的气候环境变化载体,对揭示该时期仍存在争论的季风演化及其驱动机制具有重要意义.通过对黄土高原北部保德上新世孢粉研究,发现其生态环境经历了5.6～4.4Ma温暖湿润的森林草原,4.4～3.5Ma温暖偏干的疏树草原,到3.5～3.05Ma干草原,3.05～2.8Ma森林草原的演变过程.与已发表的高原中南部记录进行时空对比,发现～3.5Ma之前乔木含量普遍较高且存在南北梯度变化,表明黄土高原早上新世处于强夏季风控制之下,对应全球冰量低值期,指示全球变化对东亚夏季风的驱动作用在那时已经存在.
The Loess Plateau dust red clay sequence is an important carrier of climate change in the Late Miocene to the Pliocene in China, which is of great significance to reveal the monsoon evolution and its driving mechanism still controversial in this period. The sporopollen research indicated that the ecological environment experienced a warm and moist forest prairie of 5.6 ~ 4.4Ma, warm and dry prairie of 4.4 ~ 3.5Ma, the steppe of 3.5 ~ 3.05Ma steppe and 3.05 ~ 2.8Ma forest steppe Compared with the published records of central-southern plateau, we found that the arborous content was generally high before ~ 3.5Ma and there was a gradient of north-south gradient, indicating that the Pliocene in the Loess Plateau was under the control of the strong summer monsoon, corresponding to the low global ice volume , Indicating that the driving forces of global change on the East Asian summer monsoon have existed at that time.