Identity of models in taper functions for Mimosa scabrella Bentham in native stands in the Curitiba metropolitan region.

Abstract

The objective of this research was: to evaluate the acuracy of three taper functions to estimate volumes along the stem of Mimosa scabrella, by age class, and by the total of the data; to test the possibility of grouping the models by the identity of models test. The data base came group 121 trees of Mymosa scabrella cubed by the method of Hohenadl with ten sections. All sample trees came from the Metropolitan Region of Curitiba (PR). The 121 trees were divided into 4 age classes. It was proceeded the adjustment of three non-segmented taper models by age class and by the total group of data. The tested models were those proposed by Schöepfer (1966), Hradetzky (1976) and Kozak; Munro; Smith (1969). After the analysis of results it was concluded that the model from Hradetzky (1976) was the best, as for estimating diameters, as for estimating volumes, for almost all age classes. It was also the best for the total data set. The identity test for the three tested models showed that it can be grouped the age classes 13 to 15 and 16-19 years. The age classes 6 to 9 and 10 to 12 only can be grouped for the 5º degree and for the Kozak models.