Grãos de pólen e esporos do Vale do Rio Caí, nordeste do Rio Grande do Sul, Brasil: descrições morfológicas e implicações paleoecológicas

Abstract

Modern pollen grains and spores of the main species occurring in the Cai River Valley, Southern Brazil, are analyzed in their morphological aspects looking for distinct morphologies. Moreover, this species were compared with those dispersed in Late Cenozoic beds, providing support to paleoecological and paleoclimatic inferences. The four main vegetations growing today around the valley and included in the broad Mata Atlantica biome were sampled and are represented in the palinomorph assemblage: the Mixed Rainforest with Araucaria, the Seasonal Deciduous and Semideciduous forests and the Steppe (Campos). The pollen grains were processed by the method of acetolysis and each type described, measured and illustrated. Among the 93 palynomorphs analyzed, 63 are unpublished data for Rio Grande do Sul State, attesting the lack of data about its palinological assemblages. Key words: pollen, spores, Quaternary, Cai River Valley, Southern Brazil.