Vegetation change in a climatic cycle of Early Pleistocene age in the Leffe Basin (Northern Italy)

摘要: Abstract The Plio-Pleistocene deposits of the Leffe Basin in Lombardian Pre-Alps Italy, first investigated quarry and lignite mine shafts by Lona 1950, were recently cored. pollen record part this core reveals a sequence four climatic cycles. One them, which is about −1.6 Ma old particularly characteristic, discussed here. A long interglacial stage can be identified dominance deciduous trees temperate climate. It clearly shows forest succession mixed oak dry-temperate climate, followed strong development Juglandaceae assemblage rich Arcto-Tertiary elements, some them indicating wet In particular, Carya peaks appear to linked warm-temperate (14–16°C mean annual temperature), humid, maritime climate with growth season, if we compare modern fossil analogs. This cooling leading phase coniferous forest. subsequently interrupted brief period open vegetation, drier colder, continental new vegetational cycle. evolution comparison other recent successions uppermost Pliocene age Mediterranean area. cycle described estimated have lasted 30 ka. entire lacustrine records eight cycles moderate amplitude. We suggest that cyclicity has been induced obliquity forcing. Correlation cold phases major glacial events Southern Alps, as proposed Venzo (1950) (1950), excluded.