Phenology of Psychotria tenuinervis (Rubiaceae) in Atlantic forest fragments:: fragment and habitat scales

The objective of this study was to investigate (1) whether the reproductive phenology of Psychotria tenuinervis Muell. Arg. is influenced by climatic conditions (precipitation and temperature); (2) whether there are differences in the reproductive phenology of P.atenuinervis between fragments (fragment scale); and (3) whether there are differences in the reproductive phenology of P.atenuinervis among anthropogenic edges, natural edges, and in the forest interior within a fragment (habitat scale). The patterns of flowering and fruiting found in 2002 and 2003 were similar between forest fragments, and proximate factors were not very important in determining the reproductive phenology of P.atenuinervis. There was phenological similarity among the three habitats on a habitat scale, probably because of the extensive heterogeneity within each habitat, with the percentage of flowering and fruiting individuals and the intensity and duration of these phenophases varying among the sample plots. This high variability within habitats indicated that factors other than the distance from the edges (i.e., gaps, matrix composition, and edge age) probably had a greater influence on the reproductive phenology of P.atenuinervis. These results also indicate that heterogeneity within fragmented habitats needs to be considered in conservation and management programs for fragmented landscapes.