Palaeovegetation dynamics of an ecotone forest-savannah in the southern Brazilian Amazon during the late pleistocene and holocene based on carbon isotopes of soil organic matter - Pessenda, Luiz Carlos Ruiz; Gouveia, S. E. M.; Freitas, H A; Gomes, B M; Aravena, R; Ribeiro, A S; Boulet, R (International Conference on the Study of Environmental Change Using Isotope Techniques, 2001)