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Objetivou-se avaliar a exatidão do dendrômetro ótico Criterion RD 1000®, em um sistema de integração lavoura-pecuária-floresta, para mensuração do volume total e por secções com casca de eucalipto. As árvores selecionadas foram derrubadas, tendo seus volumes obtidos pelo método de Smalian por cubagem rigorosa. O mesmo método foi utilizado para cubagem não destrutiva, sendo usado o Criterion para obtenção dos dados. Verificou-se homogeneidade de variâncias pelo teste de Bartlett para o volume total (p-valor 0,5125) e diâmetros ao longo do fuste (p-valor 0,1891). Não foram observadas diferenças entre os volumes totais obtidos pelo método destrutivo, não destrutivo e com o fator de forma médio. Os diâmetros ao longo do fuste obtidos pela cubagem destrutiva foram iguais àqueles obtidos pela cubagem não destrutiva. Para o volume por seções do fuste, verificou-se que apenas nas seções mais próximas ao topo, e considerando o volume até a ponta, houve diferença quando comparado ao volume real, mas refletindo cerca de 9% do volume total. As medições obtidas com o Criterion RD 1000® apresentaram-se sem tendências, fornecendo mensurações confiáveis, tanto para o diâmetro quanto para o volume ao longo do fuste.

O objetivo desta pesquisa foi avaliar o efeito da idade no ajuste de funções de afilamento e na evolução do sortimento em árvores masculinas e femininas em plantios de Araucaria angustifolia. Foram amostradas 60 árvores da espécie em um plantio localizado no município de Laranjeiras do Sul, Paraná. Ajustou-se o polinômio de quinto grau para o total de dados, estratificando-os em classes de idade. Foi analisada a evolução do afilamento e do sortimento das árvores com a idade. Os resultados mostraram uma leve vantagem no uso de equações ajustadas por classes de idade e uma melhoria significativa na forma do tronco com o aumento da idade. As árvores femininas (0,9975 m3) apresentaram crescimento mais elevado que as masculinas (0,9384 m3) aos 30 anos. Volumes para os sortimentos mais nobres são produzidos somente a partir da classe de idade 11 a 15 anos. The objective of this research was to evaluate the effect of age on adjust taper functions and evolution of the assortment of male and female trees of Araucaria angustifolia stands. Sixty trees were sampled in a plantation located in the municipality of Laranjeiras do Sul, Paraná state, Brazil. The fifth degree polynomials were adjusted to the whole data set, and they were stratified into age classes. The evolution of the tapering and assortment of trees was analyzed with age. The results showed a slight advantage in the use of equations adjusted for age classes and a significant improvement in the stem form with increasing age. The female trees presented higher growth (0.9975 m3) than the male trees (0.9384 m3) at 30 years of age. Volumes for the noblest assortments are produced only when the stand reaches the age class of 11 to 15 years.

The research aimed to evaluate the evolution of stem taper and wood assortment in plantations of Araucaria angustifolia. The data came from 30 sampled trees in plantations established between the decades of 1940-1960 in Irati National Forest, Parana State, Brazil. The trees were subjected to the technique of complete stem analysis that allows reconstitution of the entire past growth. The data generated allowed the obtaintion of diameter at different heights at various ages. The mean stem profile by age was obtained from taper functions and cubic splines functions were used to evaluate the evolution of wood assortment by age classes. We also conducted studies on the stem taper dynamics with the use of form factors. The results were presented with the mean of all trees and grouping them into two site classes, when the trees are 50 years old they reach an average volume of 1.20 m3, of which 14% could be used for lamination, 66.2% for sawmill 2, 15.9% for sawmill 1, 3.7% for pulpwood and only 0.3% would be residuals. In this same age the sites I and II had mean total volume of 1.94 m3 and 0.57 m3, respectively. The 5th degree polynomial function adjusted by age classes allowed to infer that stem tapering improves with age, with the stem becoming more cylindrical. This same trend can be established on the form factor, which practically stabilized after the 35 years of age, at a value of about 0.6.

The aim of this study was to assess and model the evolution of the hypsometric relationship in Araucaria angustifoliaplantations grown in the 1940’s and 1960’s in the Irati National Forest, in the mid-south region of Paraná state, Brazil. Using thecomplete stem analysis method, it was possible to reconstitute the past annual growth of the diameter at 1.3 m (d) and of the totalheight (h) of a sample of 30 trees, selected so as to cover diametric and age variability. Eleven discs were removed from each tree at0.1 and 1.3 m and at 15, 25, 35,..., 95% of the total height. Eleven models traditionally used in hypsometric relationships were tested,two of which were considered generic because they involved the age variable. The models were selected based on the AdjustedCoefficient of Determination (R²Adj), Standard Estimate Error (Syx), absolute (m) and relative (%), and on the graphic distribution ofresidues in percentage. In the models tested by age, no tendencies were observed and erros (Syx) remained below 14.6%, except for ages5 and 11. However, the coefficients of determination were low, ranging from 0.29 to 0.55. The Curtis generic model (1970), selectedto represent the h/d curve for all ages, also presented a satisfactory performance (R²Adj = 0.87 and Syx = 16%), with results similar tothose obtained for the models in each age. As age increases, the h/d curve shifts to the right and changes level, remaining steep at theyounger ages and more stable and flat as the population nears the end of its cycle.

O objetivo deste trabalho foi ajustar modelos de afilamento para Pinus taeda utilizando-se dados de análise de tronco de 120 árvores amostradas em povoamentos localizados no Estado de Santa Catarina. Os polinômios de quinto grau e de potências inteiras e fracionárias foram ajustados para dados sem estratificação e estratificando-os em classes de idade, avaliando a necessidade ou não de desenvolver modelos por classe de idade. Foi realizada a validação e aplicado um teste de identidade sobre o modelo de melhor ajuste, a fim de verificar a necessidade de estratificação dos dados. O polinômio de potências inteiras e fracionárias foi selecionado para as estimativas dos diâmetros nas diferentes alturas do fuste. As equações de afilamento obtidas para as classes de idades apresentaram certa superioridade em relação à equação geral, sugerindo que, ao se trabalhar com dados em classes de idade, pode-se obter maior precisão nas estimativas dos diâmetros ao longo do tronco. The aim of this work was to adjust taper models for Pinus taeda using data from complete stem analysis of 120 trees sampled in stands located at the state of Santa Catarina, Brazil. The polynomials with integer and fractional powers and the fifth degree were adjusted to the data set without stratification; they were then stratified in age classes, evaluating the necessity to develop models for age class. Validation was performed and a test of identity was applied on the best polynomial to verify the need for data stratification. The polynomial with integer and fractional powers was selected to estimate diameters at different stem heights. The taper functions obtained for the age classes showed some superiority in comparison with the general equation, suggesting that more accurate estimates of diameters along the stem can be obtained when working with data on age classes.