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通过总结中国不同区域现有的孢粉资料 ,发现第四纪孢粉植物群的演化序列中明显地存在与演化趋势和周期不符的孢粉植物群事件。归纳起来有三种类型 :延续时间约万年的孢粉植物群突变事件 ;延续时间约千年的孢粉植物群贫乏事件和延续时间几百年的孢粉植物群颤动。突变事件有 4起 :Betula- Artemisia事件 ( 2 .5Ma B.P.) ;Artemisia- Gramineae事件 ( 1 .4Ma B.P.) ;Ephedra- Chenopodiaceae事件 ( 0 .8Ma B.P.)以及 Pinus- Betula事件 ( 0 .2 Ma B.P.)。它们是第四纪气候旋回和地层划分的重要依据之一。贫乏事件有 1 1起 ,首次发现于陕西黄陵剖面 ,故称为 HL1- 11事件。该事件位于黄土古土壤界面处的黄土中 ,记录了冬夏季风强烈交替的过程。颤动事件有 6起 ,以湖泊和海洋沉积物中记录较完整 ,黄海 QC2 孔具代表性 ,故称为 HH1- 6事件。其孢粉序列表现为大幅度的摆动 ,处于全新世环境变化阶段的界面附近。
By summarizing the existing pollen data in different regions of China, it is found that there are obviously pollen flora events in the evolution sequence of Quaternary sporo-pollen flora which are inconsistent with the evolution trend and period. There are three types to summarize: mutation events of spore-pollen flora that last for about ten thousand years; paucity of sporopollen-bearing flora that lasts for about a thousand years; and fibrillation of sporopollen flora that last for hundreds of years. There were four mutations: the Betula-Artemisia event (2.5 Ma BP), the Artemisia-Gramineae event (1.4 Ma BP), the Ephedra-Chenopodiaceae event (0.8 Ma BP) and the Pinus- Betula event (0.2 Ma BP) . They are one of the important bases for Quaternary climatic cycles and stratigraphic division. There are 11 cases of poverty and the first discovery in the section of Huangling in Shaanxi Province, so it is called HL1-11. This event is located in loess at the loess paleosol interface and records the intense alternation of winter monsoon and summer monsoon. There were 6 tremor events, with relatively complete records in lakes and marine sediments. The Yellow Sea QC2 was representative, so it was called the HH1-6 event. The sporopollen assemblages showed a sharp swing, which is near the interface of Holocene environmental change.