Estabelecimento de Bertholletia elxelsa Bonpl. em área de restauração florestal na amazônia oriental

Abstract

The study aims to evaluate the spatial distribution using surface maps based on mortality, herbivore attack and sprouting of Bertholletia excelsa Bonpl seedlings. (brazilian nut) planted in a forest restoration area in the region of Carajás, southeast of the Pará state. The experiment was conducted in area of four hectares, located around the National Forest of Carajás. The evaluations were carried out through a continuous inventory of 256 plants at 11, 18 and 23 months after the implantation of the seedlings in the field. The theoretical models were selected based on the highest determination coefficient (R2), in which at 11 months of age (R2 of 0.9) the Gaussian model provided the best fit. In the evaluations of 18 and 23 months after planting, the exponential model stood out with R2 values of 0.71 and 0.74. The degree of spatial dependence was strong for the evaluations, regardless of the sampling period, with the value not exceeding 14.54% and a range of 134 meters. The observed mortality rate was 74.66%, with 62.10% due to different causes and 12.56% due to herbivores. The regrowth percentage was 7.59%, expressing the species' capacity to regenerate after suffering disturbances. The brazilian nut tree presents a heterogeneous behavior and with high mortality rates, which shows low adaptability in implantations in a degraded area in the initial forest restoration stage.