© International Society for Tropical Ecology

Abstract: This paper describes the reproductive phenorhythms of tree species in a tropical seasonal lowland forest in Southeastern Brazil. Every two weeks, five individuals of 41 species were observed for the occurrence of flowering and fruiting, from May 1982 to December 1992. All phenophases showed high seasonality, when considering the whole set of species, but the amplitude of the cycles was much more variable between years; only 13 species had regular flowering. Infra-annual flowering and fruiting were found in 11 and four species, respectively, while only one species flowered and fruited continually. Supra-annual cycles were observed in four (flowering) and seven (fruiting) species. An increase was observed in number of species and individuals flowering and fruiting from 1990 to 1992, following mainly an elevation in the absolute minimum air temperature. These data suggest a relationship between reproductive phenology and major climatic phenomena like “El Niño ” events and solar activity cycles. Resumen: El objetivo de este trabajo fue describir los fenoritmnos reproductivos de algunas especies arbóreas en un bosque tropical estacional semideciduo en el sudeste de Brasil. La presencia de floración y fructificación fue observada en cinco individuos de 41 especies con una frecuencia quincenal, desde mayo de 1982 hasta diciembre de 1992. Considerando a