Sprecher
Beschreibung
The Late Palaeozoic Ice Age (LPIA) was the Earth’s most intense Phanerozoic glacial event, now seen as a dynamic succession of glacial and nonglacial intervals during Carboniferous–Permian times. It has been hypothesized that the LPIA is linked to a CO2 decline partly driven by the colonization and diversification of land plants. Based on a new comprehensive compendium of late Palaeozoic (middle Mississippian–Guadalupian) plant families, summarising key information for global vegetation patterns, and temporal variations of floras due to palaeogeography, we have recently characterised the Palaeophytic–Mesophytic transition using a series of diversity rate metrics and multivariate analyses, including network analysis. The observed pattern of global biodiversity changes of vegetation has been related to LPIA glacial and nonglacial phases, as well as latitudinal and tectonically driven landscape changes. In this communication, new analyses show the impact of palaeogeography on this late Palaeozoic vegetation transition. Thanks to recent palaeoclimatic and palaeogeographical models, vegetation changes have been reconstructed within the main plant palaeokingdoms (phytochoria), i.e., Euramerica, Cathaysia, Angara and Gondwana, providing a new comparative framework. Results reveal highly palaeogeographical-based dynamics of heterogeneous changes from the late Palaeozoic coal swamps. For instance, while Pennsylvanian tropical wetlands in Euramerica collapsed, the early Permian swamps in high latitudes such as Angara and Gondwana underwent a great expansion. Importantly, results further reveal a major diversification pattern of tropical Cathaysian floras during the Permian similar to the observed diversification in higher latitudes. It supports phytogeography plays a crucial role in our understanding of floristic changes through time.