Distribution of total height, transverse area and individual volume for Araucaria angustifolia (Bert.) O. Kuntze.

Abstract

This study aimed to test probability density functions for the distribution of variables total height, transverse area and individual volume, considering three different class intervals. Data were obtained from the measurement of diameter (DBH) and total height and from estimation of the individual volume of 338 pine trees in a fragment of Mixed Ombrophylous Forest with an area of 15.24 ha, which is located in Jardim Botânico campus of UFPR, Curitiba-PR. Ten functions were fitted, including commonly used models for diameter distribution as well as other recently developed models applied to forest science. Selection criteria included Kolmogorov-Smirnov adherence test, standard error of estimate in percentage and adjusted coefficient of determination. Three class intervals were used as obtained by Sturges, Dixon & Kronmal, and Velleman criteria. The Normal function for variable height, and the Weber function for distribution of transverse area and individual volume, provided the best fit, considering the three class intervals adopted. The models fitted better for larger size class intervals as obtained by Sturges rule.

Dinâmica da distribuição diamétrica de povoamentos de Pinus taeda, na região de Caçador, SC

“…Para as idades de 4,5; 5,5; 6,5 e 7,5 anos, a distribuição dos diâmetros foi assimétrica negativa e a curtose foi platicúrtica. Machado et al (2010), estudando a distribuição da altura total, da área transversal e do volume individual de Araucaria angustifolia em Curitiba, PR, encontraram assimetria positiva para área transversal e volume individual. Já para altura, as curvas foram simétricas ( 0) e a curtose foi mesocúrtica.…”

“…As fdp's possibilitam obter a probabilidade de as árvores ocorrerem dentro de intervalos ou classes de diâmetro, em que haja um limite inferior e um superior. Algumas funções de densidade probabilísticas são: Weibull, Meyer, Gamma, S B de Johnson, Normal, Log-normal, Beta (Carelli Netto, 2008), "A" de Charlier, Peaerl-Reed (Alvarez Gonzalez & Ruiz Gonzalez, 1998), de Weber (Machado et al, 2009a;Machado et al, 2010), de Quadros e de Pélico Netto (Machado et al, 2010).…”

“…Devido à sua importância, a distribuição dos diâmetros tem sido estudada para diferentes povoamentos, espaçamentos e densidades e, para descrevê-las, diversas funções de densidade probabilísticas têm sido ajustadas. Dentre esses estudos, merecem destaque os de Alvarez Gonzalez e Ruiz Gonzalez (1998), Bartoszeck et al (2004), Machado et al (2006), Nogueira et al (2006), Carelli Netto (2008 , Schneider et al (2008), Machado et al (2009a), Machado et al (2009b), Machado et al (2010), entre outros.…”

Proposed Methodology for Quality Preselection of Rice Populations

“…The results of the physical-chemical characterization of the P×D population for each analyzed parameter were grouped into nine classes following Sturges's equation (population size N = 218) (Machado et al 2010). Scores of Quality Parameters.…”

“…Scores of Quality Parameters. The results of the physical-chemical characterization of the P×D population for each analyzed parameter were grouped into nine classes following Sturges's equation (population size N = 218) (Machado et al 2010). The maximum and minimum values of each class for each parameter were obtained from the dataset resulting from the analysis of each treatment.…”