Predição da estrutura diamétrica de espécies comerciais de terra firme da amazônia por meio de matriz de transição

Abstract

This research was originated from a data base of two 100% inventories accomplished in 1984 and 2000 on a same area of 576 hectares of primary tropical forest, located in the National Forest of Tapajós, Belterra, Pará, Brazil.The objective of this research was to evaluate the evolution of diameter structure of 6 commercial tree species in an Amazonian upland forest for the period from 1984 to 2000, and to project it to the year 2016, by using transition matrix. In the two inventories, circunference at breast height (CBH), in cm, were measured with measuring tape, and in 1984, the commercial heights were measu red with the hypsometer of Weiss and, in 2000, estimated with the use of sticks; minimum DBH in 1984 were 55 cm for all species and, in 2000, minimum DBH of 35 cm. The construction of the transition matrix was preceded by an exploratory data analysis (EDA), where the box plot was used for outliers detection and the graph stemand- leaf was used to filter the extreme observations. The analysis of the diametric structure showed that the evolution of DBH observed in the period 1984-2000, presented behavior differentiated by species, although maintaining the basic form of the typical distribution of each species, while the projection of the diametric structure for 2016, using transition matrix remained with the expected tendency, according to the expressed growth rates for the latent roots of the transition matrix, demonstrating to be compatible with the profile of the diametric structure observed in the year 2000.