Mid- and late Holocene vegetation, climate and fire dynamics in the Serra do Itatiaia, Rio de Janeiro State, southeastern Brazil

Abstract

We present a high-resolution pollen and charcoal record from the 350-cm Agulhas Negras (AN) sediment core from the Serra do Itatiaia, Itatiaia National Park, located at 2410 m altitude in Rio de Janeiro State, southeastern (SE) Brazil. Diverse campos de altitude (high elevation grassland) with small areas of montane forest and periodic fires dominated the landscape during the period of the last 7430 cal yr BP. Montane forest expanded after 4870 cal yr BP, reflecting a transition to wetter late Holocene climatic conditions. Araucaria angustifolia was rare in the Serra do Itatiaia and is evidenced only after 4200 cal yr BP. Fires may have markedly reduced montane forest cover between 4450 and 4000 cal yr BP. Continuous expansion of montane forest under moister conditions and the general absence of fire after 1960 cal yr BP was interrupted by a local fire event at about 530 cal yr BP. Increased fires may have limited montane forest expansion under the wet climatic conditions of the last 600 years. During this period Araucaria angustifolia became more frequent in the montane forest. Further paleoecological work is necessary to better document the natural and human-influenced relationships between climate, vegetation and fire in the high mountain vegetation of SE Brazil.