| ABSTRACT The core PD-67 of 160 cm depth was collected from the delta of Lake Cabaliana situated on the Solimões River. Seventeen samples were removed for palynological and sedimentological analysis and three for radiocarbon analysis. Two dry periods, both in the Late Holocene, were observed (2800-2550 cal yr BP, 1450-550 cal yr BP) separated by a wetter phase (2550-1450 cal yr BP). In 2800-2550 cal yr BP, varzea forests of Alchornea, Symmeria, Cecropia, Alternanthera and Asteraceae were predominant. Beginning in 2,550-1450 cal yr BP, the varzea was characterized by pioneer elements, such as Cassia, Laetia, Mabea, Symmeria and Cecropia, and by the expansion of Poaceae, Cyperaceae, Sagittaria, Montrichardia and Asteraceae. In 1450-550 cal yr BP the... |
