Palynology of the Lower Triassic succession of Tulong, South Tibet — Evidence for early recovery of gymnosperms

The thermally altered but otherwise well preserved Early Triassic palynomorphs from the Tulong area (South Tibet) allowed for qualitative and quantitative analyses and the differentiation of two distinct palynofloras, a Smithian lycopod-dominated flora and a Spathian gymnosperm-dominated flora. This suggests that gymnosperm vegetation recovered about 2 Ma after the end-Permian event on the subtropical North Indian Margin. Together with previously described successions from Pakistan, Australia, and Norway the new palynofloral record suggests an earlier establishment of diverse, gymnosperm-rich plant communities after the end-Permian event than previously proposed. The observed change in the ratio of the two major plant groups (pteridophytes/gymnosperms) in these two assemblages supports the global extent of a major climate change near the Smithian–Spathian boundary. The observed palynofloral patterns are closely related to the changes in the carbon isotope record, which suggests that the floral recovery dynamics were linked to environmental conditions.