Pollen-based quantitative paleoclimatic record spanning the Mid-Brunhes Event in the Nihewan Basin, north China

• Published in: Palaeogeography, palaeoclimatology, palaeoecology palaeoclimatology, palaeoecology, 2023-02, Vol.612, p.111377, Article 111377
• Main Authors: Da, Shuoqiang, Zhang, Zhen, Li, Yuecong, Xu, Qinghai, Fan, Baoshuo, Wang, Siyu, Dong, Jin, Wang, Yong, Chi, Zhenqing
• Format: Article
• Language: English
• Subjects: Mid-Brunhes Event; Middle Pleistocene; Nihewan Basin; Paleoclimatic quantitative reconstruction; Pollen assemblages
• ISSN: 0031-0182; 1872-616X
• DOI: 10.1016/j.palaeo.2022.111377

The Middle Pleistocene is an important period of global climatic and environmental evolution during the Quaternary. We conducted pollen analyses of 144 fossil samples and combined 1436 modern surface samples to characterize the processes of vegetation succession and climate change in the Nihewan Basin during the Middle Pleistocene, especially the Mid-Brunhes Event. The results showed that the pollen assemblages during 0.8–0.3 Ma were dominated by herbaceous pollen (> 60%), indicating that the vegetation in the study area was mainly forest steppe. The quantitative climatic reconstruction indicates that annual average temperature (Tann) was generally >6 °C, and annual average precipitation (Pann) was generally >490 mm. The warm climatic conditions persisted for a long interval, and the interval of cold conditions was shorter. Compared with the warm period, during the interval of cold climate Tann decreased by ∼4 °C, and Pann decreased by ∼130 mm. The interval of 0.478–0.424 Ma, Picea dominated the pollen assemblages (> 80%), Tann was generally 500 mm for the most period.•The warm period is longer than the cold period.•Picea > 80%, Tann