Biodiv Sci ›› 2022, Vol. 30 ›› Issue (11): 22295.  DOI: 10.17520/biods.2022295

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

Vegetation diversity and distribution in the Pliocene of the southern Hengduan Mountains region

Yongjiang Huang1,*(), Tao Su2, Hai Zhu3,4, Linbo Jia1, Jinjin Hu1, Yunheng Ji1, Zhekun Zhou1,2   

  1. 1. Key Laboratory for Plant Biodiversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201
    2. Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303
    3. College of Life Science, Shangrao Normal University, Shangrao, Jiangxi 334001
    4. State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008
  • Received:2022-06-01 Accepted:2022-08-12 Online:2022-11-20 Published:2022-08-19
  • Contact: Yongjiang Huang

Abstract:

Aims: Due to complex geomorphology and diverse landscapes, the southern Hengduan Mountains region is home to highly diverse vegetation. The evolution and formation of such diversity is an interesting topic in the fields of botany and ecology, and plant fossils are an important proxy for researching this question.

Methods: In this study, we integrated published sources of nine fossil floras from the Pliocene of the southern Hengduan Mountains region. We first inferred the vegetation types of these fossil floras on the basis of their taxonomic compositions and dominant elements, and then depicted the diversity and spatial distribution of vegetation in the region during the Pliocene. We also correlated the rise of vegetation diversity and the formation of vegetation distribution to major environmental changes in the southern Hengduan Mountains region.

Results: Our synthesis indicates that the southern Hengduan Mountain region already held a variety of vegetation types during the Pliocene, including subtropical evergreen broadleaved forest, subtropical deciduous broadleaved forest, sclerophyllous evergreen broadleaved forest, mixed coniferous broadleaved forest and shrubby meadow. The vegetation tended to have a warm affinity in the south and a cool-temperate affinity in the north, demonstrating altitudinal gradients with latitude at that time. Moreover, vegetation types are shown to be stratified at some localities, suggesting altitudinal gradients at local scales that are likely associated with the occurrence of high mountains. These are highly similar to the modern patterns of vegetation diversity and distribution in this region.

Conclusion: Our study concludes that the modern diversity and distribution of vegetation in the southern Hengduan Mountain region was established no later than the Pliocene. However, more plant fossils from deeper times are needed to verify if the current vegetation was formed at an earlier geological age.

Key words: Hengduan Mountains, Pliocene, fossil flora, palaeovegetation, palaeoelevation