Funções de afilamento segmentadas e não segmentadas para povoamentos de Tectona grandis L.f. no município de Rosário Oeste – MT

Abstract

This study was conducted in a stand of Tectona grandis L.f. in a property in the city of Rosario Oeste, Mato Grosso. The purpose of this study was to compare the accuracy of estimates of the diameters along the stem of that species offered for non-segmented and segmented polynomial models adjsuted for all of data and control of diameter classes, and also compare the accuracy of the estimates the partial volumes at different relative heighs for the total data set and adjusted by diameter class. The database consisted of 114 trees distributed among diameter classes according to the standard deviation. The tree scaling was performed by the modified hohendl methodology and the volumes were calculated by the Huber”s formula formula. The non-segmented models tested were Fifth Degree and Hradetzky 1976, and segmented models were Max and Burkhart and Clark et al. 1991. The adjustment of the models was evaluated according to the corrected coefficient of determination (R ²), standard error of estimate (syx%) and the distribution of residuals (%). The accuracy of the models was evaluated by the Deviation (D), the Standard Deviations of Differences(SD), Sum of Squares of Relative Residues (SSRR) and Percentage of Residues (RP), which allow a detailed assessment of the estimates of the diameters and volumes along bole. From these statistics a further classification was developed to detect the model provided the best estimates of the diameters and volumes along the bole. The Hradetzky equation was more accurate to estimate diameters along the stem, both for adjusting the total data set as for the diameter classes except for class 3 where the Clark et al. equation was more accurate. To estimate the volumes along the bole the Fifth Degree equation was most accurate for the entire set of data and also for classes 2 and 3, while the equation of Max and Burkhart was more accurate for Class 1, and the Hradetzky equation for Class 4 and 5. The Max and Burkhart equation accurately estimated the volumes of the base of stems for all classes and the total set of data.