02278nam a2200169 a 450000100080000000500110000800800410001910000180006024501440007826001500022252016340037265000270200665000120203370000220204570000180206770000230208521193122020-01-27       2019    bl uuuu     u00u1 u    #d1 aDANTAS, A. R.  aPopulation structure of Pentaclethra macroloba (Willd.) Kuntze in high and low floodplains of the Amazonian estuary.h[electronic resource]  aPesquisa Florestal Brasileira, v. 39, e201902043, p. 328, 2019. Edição especial dos resumos do IUFRO World Congress, 25., 2019, Curitiba.c2019  aThe flood cycle of floodplain forests and topographic variations are important factors of diversification and morphological and ecophysiological adaptations of the plant community. Pentaclethra macroloba is a hyperdominant species adapted to flood variations. The objective of this study was to characterize the P. macroloba population structure between environments with high topography, flooded only during the rainy season and peak flood of the river, (high várzea-HV) and low topography with daily flood (low várzea-LV). The study was carried in the Mazagão Experimental Field, Brazil. Four plots of 1 ha were installed in each environment. All individuals with DBH ≥ 5 cm were measured and georeferenced. ANOVA test, 0.05% probability, was applied to verify the structural differences between two environments. The HV had higher population density (51.2 individuals.ha-1) compared to the LV (36.7 individuals.ha-1), although without significance. Basal area was higher in the HV (10.42 m²) in comparison with LV (5.90 m²), with significant difference (F = 7.13, p = 0.00795). The maximum DAP of HV was 67 cm with mean of 24 cm. The LV presented maximum DBH of 42 cm with mean of 21 cm, showing structural difference between the two environments (F = 6.22, p = 0.0131). The aggregation index showed high aggregation in the LV (R = 0.89) than in the HV (R = 0.79), differing significantly between the two environments (F = 11.31, p = 0.0008). Frequency and time of flooding are ecological drives that structure the population of pracaxizeiro causing morphological and ecophysiological adaptations to the individual.  aDinâmica Populacional  aPracaxi1 aPIEDADE, M. T. F.1 aGUEDES, M. C.1 aLIRA-GUEDES, A. C.