Evidence of dry and cold climatic conditions at glacial times in tropical southeastern Brazil

Last-glacial paleoenvironments have been reconstructed from a pollen and charcoal record analyzed in organic sediments and dated between ca. 18.000 and >48,000 C-14 yr B.P. The site is located near the village Catas Altas in the lower highland region of southeastern Brazil, The last-glacial landscape was covered by extensive areas of subtropical grasslands and small areas of gallery forests along the rivers, where tropical semideciduous forests and cerrado ecosystems exist today. The subtropical gallery forests were composed of Araucaria forest trees such as Araucaria angustifolia, Podocarpus, Drimys, Ilex, and Symplocos. Paleofires were frequent. The record indicates that subtropical grassland vegetation, which today is found in patches on the highlands in southern Brazil (especially in the state of Santa Catarina), expanded from southern Brazil to southeastern Brazil, over a distance of more than 750 km, from latitudes of about 28 degrees S to at least 20 degrees S, The completely different last-glacial environment, in comparison to the present-day environment, reflects a dry and cold climate with strong frosts during the winter months, Temperatures of 5 degrees-7 degrees C below those of the present are inferred for the last glaciation. (C) 1997 University of Washington.