Last-glacial paleoenvironments have been reconstructed from a pollen and charcoal record analyzed in organic sediments and dated between ca. 18,000 and >48,00014C 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 ofAraucariaforest trees such asAraucaria angustifolia, Podocarpus, Drimys, Ilex,andSymplocos.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° S to at least 20° 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°–7°C below those of the present are inferred for the last glaciation.
lhe general index-plain "Sulamericana" can be found in vast areas cf SE-Brazi!. It is mainly conserved with the help of a duricrust and covered by laterite. lhe next younger element of reliefevolution, a levei 40 to 60 m below the Sulamericana, is completely dlfferent: the weathered rock is covered by a stoneline and a fine-textured sedimento lhis structure was examined with the help cf granulometry, analyses of heavy minerais, thermoluminescence datings, poIlen anaIyses and 14C-datings. Dlfferent conditions for the development cf stonelines may occur according to the climatic conditions at the time of their origin; in this case it must be assumed that the stonelines were formed by slope-wash due to episodic precipitation under the condition cf nearty complete absence of vegetation (geologic or climatic reasons). lhey are a clear post-$ulamericana development. A fine-textured sediment was deposited on top of the stonelines. lhe material of the finetextured sediment was, accordlng to the then prevaHing conditions, transported by as well slope-wash as eoIian processes; especially for the "demi-oranges" we must assume eoIian transporto lhe material was probably derived partly trom the local material which covers the remnants of the SUlamericana, but may be seen as an eoIian sediment transported for long distances as well. lhe time 01 the deposition cf the fine-textured sediment on the stonelines coincides with the climax of the last Glacial; the 14C-dating indicates 19,700 years B.P., the thermoluminescenCEHjating about 20,000 years B.P .. lhe climatic conditions were probably semi-arid. lhese results are supported by the findings of other researches of the Southamerican 'Bahnhofstr. 89, 2890 Nordenham, W.Gerrnany.
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