Late Palaeozoic wetland plant communities : palaeoecological, palaeobiogeographic and evolutionary significance

• Main Author: King, Sarah Caroline
• Published: University of Birmingham 2012
• Subjects: 560; GE Environmental Sciences
• Online Access: https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.556925

The late Palaeozoic marked the beginnings of fully established, global terrestrial ecosystems as we know them today. Large-scale provinciality of vascular plants had developed by this time, and four global phytogeographic provinces were named, superimposed on the converging Pangaean landmass: Angara (mid-high latitude north), Gondwana (mid-high latitude south), Euramerica (low latitude west) and Cathaysia (low latitude east). The low latitude provinces supported vast swathes of the famous ‘coal swamp’ wetland flora at this time. Delineation of these provinces has never been formally ratified due to most palaeobotanical work being on a local to regional scale, and results of this work being presumed as representative of a wide area. This thesis examines the wetland flora of the most contentious, low latitude provinces, and aims to assess the widely cited proposal of linkage and substantial interchange between Euramerica and Cathaysia. The proposal is upheld, specifically during the Stephanian (~305-300 Ma), when the well established flora in Euramerica migrated along a pathway through the tectonically complex Angara region and quickly colonised North Cathaysia,where it flourished and diversified after the extirpation of the source flora in Euramerica. Connections between the regions at other times are also found to be highly likely,although the complexity of the tectonic backdrop, and difficulties with characterisation of highly dynamic wetland floras, lead to ultimate recommendations to analyse the floras as fully and in as wide a context as possible, and to utilise all avenues of evidence, in order to progress in uncovering their full histories.