Distribuição diamétrica em uma floresta natural

Abstract

For the proper management of species, different tools are adopted, with the diametric distribution being one of the most efficient. This approach provides subsidies for understanding processes related to tree communities, such as the impact of previous disturbances on succession dynamics and the identification of ecological patterns of recruitment and mortality of specific species. These subsidies are fundamental to favor the management and continuity of natural resources, as well as to carry out projections in different management regimes. Diametric distributions in natural forests are modeled using probability distributions, in order to characterize the frequency of individuals in each diameter class. Thus, this study aimed to model the diametric distribution of a forest fragment located in a forest concession area in Rondônia. The forest fragment is located in the Jamari National Forest, and the data used were provided by the company Amata S/A, responsible for the forest concession in the area in 2014, when the inventory was carried out. To carry out the modeling, the probabilistic distributions generalized beta type 2 (BG2), exponential, generalized gamma (GG), normal, Johnson's Su and Weibull were used. These distributions were adjusted both for the forest as a whole and for the species Castanheira (Bertholletia excelsa) and Faveira-ferro (Dinizia excelsa), using traditional and truncated approaches. The quality of the fits was evaluated through adherence tests and analysis of the residual plots. The results revealed that Johnson's Su distribution accompanied by BG2 and GG visually had better fits for the forest and studied species. In addition, it was observed that the absolute values of the adherence tests for the truncated fit provided more accurate results compared to the traditional fit for all considered distributions. In general, Johnson's Su, BG2 and GG distributions were identified as the most appropriate, since they exhibited better distributed residues and presented lower values in the goodness of fit test.