Biodiv Sci ›› 2022, Vol. 30 ›› Issue (11): 21504.  DOI: 10.17520/biods.2021504

Special Issue: 青藏高原生物多样性与生态安全

• Special Feature: Cenozoic Plant Diversity Evolution in South China •     Next Articles

Palynological assemblage and age of the Cenozoic coal-accumulation strata in the Puyang Basin, southeastern Yunnan Province

Jiucheng Yang1,2, Jia Liu2,3,*(), Yu Li4, Tao Su2,5, Shufeng Li2, Linbo Jia6, Zhekun Zhou2,6, Shitao Zhang1,*()   

  1. 1. Faculty of Land Resource Engineering, Kunming University of Science and Technology, Kunming 650093
    2. CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303
    3. State Key Laboratory of Palaeobiology and Stratigraphy (Nanjing Institute of Geology and Palaeontology, CAS), Nanjing 210008
    4. Research Center of Paleobiology, Yuxi Normal University, Yuxi, Yunnan 653100
    5. University of Chinese Academy of Sciences, Beijing 100049
    6. CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201
  • Received:2021-12-08 Accepted:2022-03-12 Online:2022-11-20 Published:2022-08-04
  • Contact: Jia Liu,Shitao Zhang


Aims: Located in the southeastern margin of the Tibetan Plateau, Yunnan Province is mainly characterized by a typical tropical monsoon climate and hosts the richest biodiversity in China. Dramatic tectonic activities during the Cenozoic era created many intermountain basins. These sedimentary basins provide excellent opportunities for understanding Cenozoic vegetation evolution, biodiversity and paleoenvironmental change. However, the ages of the basins remain far from fully investigated. Here we use the Puyang Coal mine section, Puyang Basin, southeastern Yunnan, southwestern China, to investigate paleoclimate and the evolution of vegetation, as well as the age of the coal-accumulation strata.

Methods: In this study, 40 palynological samples were collected from different layers in the Puyang Coal mine section, and the pollen and spores were extracted using the conventional acid-base method. The samples were used to reconstruct palynological assemblages and vegetation features by identifying and counting the species, quantity and proportion of pollen in sedimentary strata.

Results:A total of 74 morphological genera of pollen were identified in this study, including 13 gymnosperms, 49 angiosperms, 10 ferns, and 2 algae.

Conclusion: The palynological assemblage of the lower part of the study section is dominated by Taxodiaceaepollenites, indicating a swamp forest with a relatively humid climate in the cold season. The palynological assemblage of the upper section indicates a mixed subtropical evergreen and deciduous broadleaved forest, dominated by evergreen oaks, along with other subtropical taxa, such as Caryapollenites, Ilexpollenites, Juglanspollenites, and Liquidambarpollenites.It represents a warm and humid climate with significant seasonality. By combining newly discovered mammal fossil and palynological evidence, we infer that the age of the coal-accumulation strata in the Puyang Basin is late Eocene. The palynological assemblage also indicates the modernization of the biota in Southeast Yunnan since the late Eocene.

Key words: palynology, Puyang Basin, Yunnan, Eocene, biodiversity