Phenology and dispersal syndromes of woody species in deciduous forest fragments of the Pantanal in Mato Grosso do Sul State, Brazil

摘要

We analyzed the phenological responses of shrub-tree species of lowland deciduous (LDF) and submontane deciduous (SFD) forests in the Pantanal, and assessed their relationships with climatic factors at the community level and with strategies for seed dispersal. Vegetative and reproductive phenophases of 50 tree-shrub species were monitored monthly (12 months), and their relationship with climatic variables was tested using multiple linear regression. Time of leaf budding differed between areas for autochoric species and between autochoric and anemochoric species at LDF. Leaf fall in communities and functional groups was seasonal and highly synchronous during the dry season (95 % of species). Leaf budding peaked at the end of the dry season with 80 % synchrony. In general, the species presented low synchrony or asynchrony for flowering phenophases, while fruiting phenophases were weakly seasonal but differed between functional groups. Temperature and precipitation were the regulating factors of vegetative phenophases in LDF, while daylength regulated them in SDF. Abiotic factors only influenced flowering phenophases at the dispersion group level. Only ripe fruits were related to reduced daylength. The phenophases of the deciduous forests of the Pantanal seem to be regulated not only by climatic factors but also by strong endogenous control.