Holocene vegetation and fire history of the Serra do Caparaó, SE Brazil
2012
P, Nuno Veríssimo | Safford, Hugh DeForest | Behling, Hermann
This study presents a recontruction of the Holocene vegetation and fire history of the Serra do Caparaó (Espírito Santo/Minas Gerais, SE Brazil) based on pollen and charcoal analysis from the 130 cm long core Primeiro Rancho I. Radiocarbon dates indicate a complete record of the Holocene (11,400 cal. yr BP to present). At the core site, high elevation grassland (campos de altitude) has been the dominant vegetation throughout the recorded period. In the early Holocene (11,400 to 9000 cal. yr BP), a humid phase was followed by a drier one. Fires occurred continuously during the studied period but were more frequent in the early Holocene. Between 9000 and 2700 cal. yr BP, a gradual increase in the diversity and abundance of Atlantic montane forest taxa indicates an increase in humidity and/or rainfall; campos de altitude taxa still dominated but the montane forest taxon Symplocos was strongly present. Between 2700 and 1200 cal. yr BP, the arboreal Atlantic montane forest taxon Luehea became prominent but forest expansion halted and apparently reversed after 1200 cal. yr BP, possibly because of human activities. Simultaneously, campos de altitude expanded; abrupt variations in the pollen assemblages suggest environmental instability. Campos de altitude are a natural vegetation in Serra do Caparaó, but their present extent is likely influenced by anthropogenic activities, as several data suggest an increase of humidity after 1200 cal. yr BP, which should have caused a forest expansion. Reduction in human disturbance at higher elevations would thus probably result in succession to forest in some of the lower campos.
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