Supporting data for "Application of plant fossils in the reconstruction of the late Triassic paleoenvironment and ecosystem in northern China"

The Triassic was pivotal in the assembly of modern terrestrial ecosystems, witnessing post–end-Permian recovery, the radiation of crown-group vertebrates, and profound floral restructuring. This thesis investigates Late Triassic plant macrofossils, cuticles, charcoal, and stratigraphic data from the Yangcaogou Formation (western Liaoning) and the Karamay Formation (Shendigou Section, northwestern Junggar Basin, Xinjiang) to clarify floristic evolution and environmental change in northeastern Pangaea. A diverse assemblage (≥77 species, 34 genera) of the Yangcaogou Flora is reassessed using detrital zircon U–Pb geochronology, providing the first direct age (~226 Ma) and enabling correlation with coeval floras from North China, Japan, Korea, and the Russian Far East, thus refining reconstructions of vegetation along the western Palaeo-Pacific margin. In the Junggar Basin, seed-fern–dominated floras with exceptionally preserved cuticles allow stomatal analyses and independent estimates of atmospheric CO₂. Abundant macro- and mesofossil charcoals indicate recurrent wildfires and reveal greater conifer diversity than previously recognized. The association of seed-fern-rich floras and charcoal supports a seasonally humid climate with episodic drying. Collectively, these data improve phytostratigraphy and illuminate terrestrial ecosystem structure and recovery during the Late Triassic.