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Studies that seek to identify potential techniques for obtaining diameter values at 1.30 m from the ground from tree height data are necessary, especially when considering the use of airborne Lidar in forest inventory activity. In this sense, this work aimed to evaluate two artificial intelligence tools for this purpose, namely the neurofuzzy inference systems and the artificial neural networks. Four models were tested to obtain estimates for the diameter variable, which were prepared by combining the independent variables useful area per plant, age and height. After processing, the statistics of bias, square root of the mean squared error in percentage, correlation and mean percentage error were calculated, in addition to the preparation of scatter plots and histogram of residues. It was observed that, for the estimation of the diameter in both techniques, the use of the model with all independent variables obtained the best values for the analysis statistics. It can be concluded that both tools can be used to estimate the diameter, with the neuro-fuzzy inference system being more suitable for its processing speed and small variability between the values obtained in different training sessions for the same database. [ABSTRACT FROM AUTHOR]

This work, prepared for the special issue of Journal Floresta, aimed to bring together the most significant contributions made by professors and collaborators in the area of Forest Management in the undergraduate and graduate courses in Forestry at the UFPR during the last 50 years. For its elaboration, it was decided by the sectorization of its content in themes, whose sequence included the evolution in the fields of forest mensuration, forest inventory, geotechnologies, statistics, planning and optimization of forest production, biomass and carbon in forests and their products, forest management, and their prospects. The reports clearly showed that during this period there were major evolutions and improvements in the training of forest engineers, as well as masters and doctors in this field of knowledge. The research was developed during this period, not only in the theoretical domain, but also in the technological and operational ground, due to the group's strong interaction with the productive forest sector and with the public institutions of the state of Paraná and the federal government. The training of masters and doctors was expressive, with the highest productivity in the Graduate Program in Forest Engineering at UFPR. In all the topics covered were presented the new directions for the evolution of scientific and technological knowledge in the field of Forest Management. [ABSTRACT FROM AUTHOR]

This research aims to analyse the diametric distribution of an Atlantic Forest fragment at Reserva Biológica Sítio Palmares, state of Espírito Santo. In 2,400 m² all trees and palms with DBH over 5 cm were measured. It identified 1364 individuals distributed into 70 species and 33 families. The community population had a DBH average of 14.82 cm and a basal area of 41.12 m².ha-1. For the total population, the DBH distribution into 5 cm intervals formed 13 classes. The adjusted Meyer's equation reveals for this population a tendency to a J-inverse curve. The first three diameter classes from 5 to 20 cm concentrated 79% of the total population. Eight species had a population density with more than 40 trees per hectare. These trees were concentrated until the 40 cm distribution classes. The statistical analysis of the distributions curves reveals that these populations were distributed between the normal, j-inverse and bi-modal curves. [ABSTRACT FROM AUTHOR]