ABSTRACT Background: Many gaps in the copaifera oleoresin yield remain unfulfilled, preventing the sustainable management of this valuable non-timber forest product. This work aimed to characterize a natural Copaifera reticulata population in the Amazon rainforest, test different positions and depths in the trees to flow oleoresin, and analyze changes in the productiveness between two harvests ten months-spaced. The study was conducted in a Brazilian rainforest area at the Jari Ecological Station (ESEC) in 2017 and 2018, including 26 trees. Results: The diametric and height distributions evidenced light-demanding and mostly medium-class-diameter trees. The annual increment (0.45 ± 0.003 cm/year) was average, while the occurrence was rare. The area hosts yielding and unyielding trees, providing an average oleoresin production of 603.60 mL/tree. Oleoresin only flowed by reaching the inner heartwood or the pith. Oleoresin was not fully replenished after ten months, but the first drilling stimulated some unyielding trees to deliver it later. Collecting should focus on medium-diameter trees. Conclusion: The growth and distribution behaviors may challenge Copaifera’s sustainable management, which depends on the individual tree mechanisms to provide and replenish the oleoresin.

RESUMO Analisou-se o padrão de distribuição espacial de Pentaclethra macroloba para auxiliar em planos de manejo e conservação desta espécie nas florestas de várzeas estuarinas. O estudo foi realizado em floresta de várzea de 55,95 ha, na cidade de Mazagão, Amapá. Foi realizado um censo e georreferenciamento de todos os indivíduos, vivos e mortos, que apresentavam a Circunferência na Altura do Peito (CAP) ≥ 30 cm. A Função K de Ripley foi utilizada para analisar o padrão de distribuição populacional, da mortalidade e das classes diamétricas. A relação da distância de inundação com a densidade e a área basal da população foi analisada utilizando regressão linear. Foram inventariados 993 indivíduos vivos e 22 mortos. A população obteve padrão agregado ao longo do gradiente topográfico de inundação. As classes de diâmetro 1 (≤ 13,2 cm) e 2 (≤ 18,6 cm) iniciaram com padrão agregado, finalizando com padrão aleatório. As classes 3 (≤ 24,0 cm) e 4 (≤ 29,5 cm) obtiveram padrão totalmente agregado e nas classes seguintes, 5 (≤ 34,9 cm), 6 (≤ 40,3 cm), 7 (≤ 45,7 cm) e 8 (≤ 51,2 cm) o padrão foi aleatório. O padrão da mortalidade foi aleatório. A densidade populacional foi 18 indivíduos h-1 e área basal de 49 m2 h-1 dos indivíduos vivos. A densidade (r2=0,51; p = 0,0195) e a área basal (r2 = 0,67; p = 0,0039) dos pracaxizeiros aumentam com o afastamento do gradiente de distância do rio. A dinâmica de inundação e o processo de dispersão são fatores relacionados com o padrão espacial e o sucesso no estabelecimento da espécie.

ABSTRACT We analyzed the spatial distribution pattern of Pentaclethra macroloba to assist in the development of management plans and conservation of this species in estuarine floodplain forests. The study was conducted in an area of floodplain forest of 55.94 ha, in Mazagão, Amapá, Brazil. A census was performed and all individuals of ≥ 30 cm circumference at breast height (CBH), living and dead, were georeferenced. Ripley’s K function was used to analyze the spatial distribution of the population, including mortality and diameter classes. The relationships between distance to the edge of inundation and density and basal area of the population were analyzed using linear regression. We recorded 993 live individuals and 22 dead. The distribution of the population was found to vary with the topographic gradient associated with the distance to the edge of the inundation. Diameter classes 1 (≤ 13.2 cm) and 2 (≤ 18.6 cm) were spatially aggregated close to the water and randomly distributed far from the water. Classes 3 (≤ 24.0 cm) and 4 (≤ 29.5 cm) were aggregated at all distances, and classes 5 (≤ 34.9 cm), 6 (≤ 40.3 cm), 7 (≤ 45.7 cm) and 8 (≤ 51.2 cm), were randomly distributed at all distances. Mortality was randomly distributed. The population density was 18 trees h-1 with a basal area of 49 m2 h-1, and both density (r2=0.51; p=0.0195) and basal area (r2=0.67; p=0.0039) increased with the distance from the edge of the inundation. We conclude that the spatial distribution and successful establishment of this species in floodplain forest are related to the dynamics of flooding and the resultant impacts on dispersal processes.