Effect of climate and flooding on the phenology of Attalea phalerata (Arecaceae) in a white‐water floodplain forest of the Amazon River.

Little is known about the effect of the polymodal tide of the Amazon estuary on the phenology of palms. We evaluated the effect of climate/flood and biotic factors on the phenology of 80 Attalea phalerata palms over 1‐year period. Bract emission and young leaves percentage were negatively correlated to accumulated rainfall. Inflorescence and leaf production occurred mainly in the dry season. Immature fruit was positively correlated with rainfall, showing that fruit development occurs during the rainy season. The production of flowers, unripe fruit, and young leaves were positively correlated to flooding. The production of infructescence, per palm, varied from 0 to 4 and 18% of the variance was explained by variables of stem diameter, number of new leaves, altitude, and flood amplitude. The number of infructescence increased for large palms and decreased for individuals subjected to high amplitudes of flooding. These findings reveal that phenological patterns of A. phalerata are driven by seasonal variation in rainfall and flooding. Furthermore, infructescence production can be predicted by plant size and this production is sensitive to variations in flood amplitude. Alteration in rainfall and flooding due to climate change may have a negative impact on fruit production if extreme events increase in frequency. [ABSTRACT FROM AUTHOR]