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Caçador, Brazil

Teo S.J.,UNOESC | Bianchi J.C.,Academico de Engineering Florestal | Peloso A.,Academico de Engineering Florestal | Nava P.R.,Academico de Engineering Florestal | And 3 more authors.

This research aims to analyze probability of density functions (pdf) Normal, Ln-Normal, Johnson Sb, 3PWeibull, Gamma, Beta and Weber in order to describe diameter changes in Pinus taeda L. plantations structure, in the region of Caçador - SC, Brazil, at different age and site classes. The data processing was carried out by Solver tool of the software MSExcel2010, using the linear algorithm of generalized reduced gradient (GRG) for interaction of parameters. As result, Johnson Sb and 3PWeibull presented the best performances. For the pdf adherence evaluation, it was recommended the employment of R2,R2 ad,syx e syx% statistics, besides the Kolmogorov-Smirnov test, in any situation, specially, when there is more than 5,000 observations. Generally, there was an increasing in the range of diameter values and a flatness of diameter distribution at advancing age and improvement of the site productivity. At age advancing, there was an increasing of maximum diameter and modal diameter values of distributions, for the higher productivity site classes, on the other hand, the same did not occur for the low productivity site class. Source

This study aimed to test different statistical models for fitting site index curves and check if the anamorphic curves generated were satisfactory to classify the loblolly pine (Pinus taeda L.) plantations in the region of Caçador, Santa Catarina State, Brazil. The data of dominant height (hdom) used in this study were obtained from permanent plots of fixed area and rectangular shape, with areas of 500 and 625 square meters. The plots were distributed randomly in the stands to cover the largest possible variability of productivity. The selection of the best equation was made by the following fitting and precision statistics: adjusted coefficient of determination (R2 aj), standard error of estimation (Syx), standard error of estimate in percentage (Syx%) and graphical distribution of the residuals in percentage. The monomolecular model showed the best performance, so it was chosen for the construction of the site index curves by guide curve method. After construction of the site index curves, the stability of the curves was also tested, which indicated the anamorphic pattern of the curves generated by the equation for site classification of loblolly pine plantations in the region of Caçador, Santa Catarina State, Brazil. Source

Teo S.J.,Federal University of Parana | Marcon A.,UNOESC | Ehlers T.,UNOESC | Bianchi J.C.,UNOESC | And 3 more authors.

The research aims to fit and select taper models in order to estimate diameters at different heights and total volumes, inside and outside bark, of Pinus elliottii Engelm. trees, in the region of Caçador - SC, Brazil, as well as to analyze behavior of stem form for trees at different ages. Altogether, 78 trees at 10, 18 and 27 years of age, had been cut and their volumes obtained by Smalian method. The taper models tested were the 2nd and 5th Degree Polynomial and the Hradetzky Polynomial of Fractioned Potencies. The best performance taper function for estimate diameters inside and outside bark throughout the stem were based on the Hradetzky Polynomial of Fractioned Potencies, for 10, 18 and 27 years of age. The 2nd Degree Polynomial provided the best estimates of outside bark volume for 10 and 27 years of age, and of inside bark volume for 18 and 27 years of age, although the Hradetzky Polynomial presented the best estimates of outside bark volume for 18 years of age and of inside bark volume for 10 years old trees. The stems of the Pinus elliottii trees present better form for the oldest tress. Source

The objective of this research was to evaluate and compare sampling methods Fixed Area, Bitterlich, Strand and Prodan, in fragments of Mixed Ombrophyllous Forest, in Lebon Régis, SC state, Brazil. The forest inventory applies a simple random sampling. At each sampling unit, we evaluated every tree with diameter at breast height greater than or equal to 5 cm. For the method of Fixed Area we used dimensions of 10 × 50 m (500 m2), for Bitterlich and Strand we adopted Basal Area Factor equal to 2, and for Prodan we evaluated the 6 nearest trees. Only the Fixed Area method presented sampling sufficiency, however, it presented highest execution time in the field as well, with results significantly different from the other sampling methods. The relative efficiency was higher for Strand, but without statistical significance compare to the other methods. There were no significant differences between the number of trees and basal area per hectare, estimated by the different sampling methods. Source

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