A review of tree phenology in Central Amazonian floodplains

Trees in central Amazonian floodplains are subjected to periodical inundations of up to seven months every year. The present paper summarizes the available data of tree phenology in Amazonian floodplains in the vicinity of Manaus, Brazil. The phenological observations included presence of leaves, leaf flush, flowering and fruiting of 76 species from 30 families. Leaves are shed mainly in the flooded period, new leaves are flushed when water recedes. The species from nutrient-rich várzea flush new leaves towards the end of the flooded period, in nutrient-poor igapó the peak of leaf flush is in the terrestrial, non-flooded period. Flowering occurs mainly at the beginning of the flooded period in igapó, while in várzea the peak is at highest water levels. The peak of fruiting is in the flooded period, in várzea later than in igapó. In both várzea and igapó, the amount of deciduous species is around 50%. In igapó a leafless period is not as evident because it is less synchronized. Although in most species analysed phenological changes occurred during the flooded period, it is not clear whether it is flooding that triggers the phenological event