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We analysed changes in mean annual air temperature (MAAt), vegetation and biomass burning on a long and continuous lake-peat sediment record from the colônia basin, southeastern Brazil, examining the responses of a wet tropical rainforest over the last 180 ka. Stronger southern atmospheric circulation up to the latitude of colônia was found for the penultimate glacial with lower temperatures than during the last glacial, while strengthening of the South American summer monsoon (SASM) circulation started during the last interglacial and progressively enhanced a longer wet summer season from 95 ka until the present. Past MAAT variations and fire history were possibly modulated by eccentricity, although with signatures which differ in average and in amplitude between the last 180 ka. Vegetation responses were driven by the interplay between the SASM and southern circulation linked to Antarctic ice volume, inferred by the presence of a cool mixed evergreen forest from 180 to 45 ka progressively replaced by a rainforest. We report cooler temperatures during the marine isotope stage 3 (MIS 3: 57-29 ka) than during the Last Glacial Maximum (LGM: 23-19 ka). Our findings show that tropical forest dynamics display different patterns than mid-latitude during the last 180 ka.

An inventory of geological sites based on solid and clear criteria is a first step for any geoconservation strategy. This paper describes the method used in the geoheritage inventory of the State of São Paulo, Brazil, and presents its main results. This inventory developed by the geoscientific community aimed to identify geosites with scientific value in the whole state, using a systematic approach. All 142 geosites representative of 11 geological frameworks were characterised and quantitatively evaluated according to their scientific value and risk of degradation, in order to establish priorities for their future management. An online database of the inventory is under construction, which will be available to be easily consulted and updated by the geoscientific community. All data were made available to the State Geological Institute as the backbone for the implementation of a future state geoconservation strategy.

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PALEOENVIRONMENTAL EVOLUTION DURING THE HOLOCENE IN THE NORTHEAST OF SÃO PAULO STATE, BRAZIL. Palynological analysis, isotopic and charcoal fragments provided information about the climate change of the last 10.250 years BP in the northeastern portion of the State of São Paulo. The samples were taken from the base of the studied trench with ages between 10.000 and 6.986 years BP. They present C 4 vegetation with values δ 13 C around -14.3 ‰, little presence of palynomorphs, and fragments of charcoal. The interval was interpreted as the result of the predominance of a drier climate than the current in the early Holocene (that lasted until the mid Holocene), under which paleofi res already occurred. From mid Holocene to the present days, the predominance of C 4 and C 3 vegetation values to -20.86 ‰, and the increase frequency of pollen grains (as Byrsonima and Didymopanax) indicating Cerrado (Brazilian Savannah) suggest that, in the interval of 2.096 years BP until the current days, the area has been covered by a mixed vegetation composed by elements of grassland and forest, indicating a regression of the grassland associated to wetter climat e, which favors the "cerradão" as cover vegetation.Key words: carbon isotopes, Cerrado (Brazilian Savannah), palynology, Quaternary, paleoclimate.RESUMO -Análises palinológicas, isotópicas e de fragmentos de carvão, forneceram informações acerca das mudanças climáticas dos últimos 10.250 anos AP na porção nordeste do Estado de São Paulo. As amostras retiradas da base da trincheira estudada, com idades entre 10.000 e 6.986 anos AP, mostraram a presença de vegetação C 4 com valores de δ 13 C em torno de -14,3‰, escassa frequência de palinomorfos e fragmentos de carvões. Esse intervalo foi interpretado como o resultado da predominância de um clima mais seco que o atual no início do Holoceno (que se estendeu até o Holoceno médio), sob o qual paleoincêndios já ocorriam. Do Holoceno médio, com ênfase a partir de 2.096 anos AP, até os dias atuais, ocorre o predomínio de vegetação C 4 e C 3 com valores -20,86‰ e o aumento da frequência de grãos de pólen, indicadores de Cerrado (como Byrsonima e Didymopanax), que sugerem que a área foi coberta por uma vegetação mista composta por elementos de campo e fl oresta, indicando uma regressão do campo associado provavelmente ao clima atual mais úmido, que favorece o "cerradão" como vegetação de cobertura.Palavras-chave: isótopos do carbono, Cerrado (savana brasileira), palinologia, Quaternário, paleoclima.