EVOLUTION OF DENDROMETRIC VARIABLES OF Mimosa scabrella BY SITE CLASS

Abstract

The identification of the growth rhythm of the dendrometric variables of forest species with the use of stem analysis is quick, efficient and of great importance in the decision making by forest managers. Thus, the objectives of this research were to analyze the annual evolution of the yield curves, Mean Annual Increment (MAI) and Current Annual Increment (CAI) in height, diameter, cross sectional area and volume of individual Mimosa scabrella Benth (Bracatinga) in different site classes, and also, to fit mathematical models to express the evolution of these variables over the years. The database came from complete stem analysis of 29 Mimosa scabrella trees collected in the metropolitan region of Curitiba, with ages ranging from seven to 18 years, distributed in three site classes. After the measurements and basic data processing, six mathematical models were adjusted for each one of the four dendrometric variables, independently for each site. The best model was chosen based on the adjusted coefficient of determination (R²aj), relative standard error of estimate (Syx%) and residual graphic analysis. The results showed that the Chapman-Richards model presented the best fitting for almost all analyzed variables in all three sites. It was also verified that the culmination order of the current annual increment followed the expected chronological order, that is, first height, then diameter, cross sectional area, and finally, volume, in all the sites.