Eocene - Oligocene vegetation and climate changes in southeastern Brazil

Autor(es)

Akabane, Thomas Kenji ; Garcia, Maria Judite ; Kern, Andrea K. ; De Oliveira, Paulo Eduardo

• Tipo de documento: Artigo Científico
• Fonte: REVIEW OF PALAEOBOTANY AND PALYNOLOGY; v. 327, p. 13-pg., 2024-06-24.

Resumo

The Eocene -Oligocene Transition (EOT) marks the onset of a major phase of global cooling with significant consequences to the vegetation worldwide. Here, we present palynological analyses from a site in southern Sa o Paulo basin, southeastern Brazil (23.67 degrees S; 46.58 degrees W). An Oligocene age was constrained by the abundance of Dacrydiumites florinii and Podocarpidites spp., alongside the presence of taxa such as Cicatrocosisporites dorogensis and Polypodiisporites usmensis. Autochthonous elements including Paleoazolla, Corsinipollenites spp. , Monoporopollenites annulatus, and Zygnemataceae algae spores are indicative of a low -energy freshwater depositional environment. In addition, we performed a comparison of Eocene and Oligocene temperature and precipitation estimates from records in southeastern Brazil using the weighted Mutual Climate Range approach. Results support global trends with a cooling of ca. 3 -4 degrees C from the Eocene to the Oligocene accompanied by slightly drier regional conditions. Oligocene environmental changes drove a vegetation turnover by local extinction of warmtropical taxa or a significant retreat of species unable to stand comparatively colder and drier climates under lower CO 2atm concentrations. Our data are consistent with previous estimates and verify the impact of global cooling on the vegetation of mid -low latitudes of the Southern Hemisphere. (AU)

• Processo FAPESP: 21/13129-8 - Regime de incêndios na América do Sul tropical durante o Quaternário tardio
• Beneficiário: Thomas Kenji Akabane
• Modalidade de apoio: Bolsas no Exterior - Estágio de Pesquisa - Doutorado
• Processo FAPESP: 19/19948-0 - Influência das mudanças climáticas sobre a flora amazônica durante o Pleistoceno tardio
• Beneficiário: Thomas Kenji Akabane
• Modalidade de apoio: Bolsas no Brasil - Doutorado