ESTRUTURA FITOSSOCIOLÓGICA E CRESCIMENTO DE Cedrela fissilis Vell. EM FLORESTA ESTACIONAL DECIDUAL NO EXTREMO OESTE DE SANTA CATARINA

Abstract

Dendrochronological studies are needed to propose knowledge allowing a better interpretation the growth of a species and forest over time. This work has as objectives to analyze the phytosociological parameters, verify subareas with similar environmental features, determine the increment, passage time between diametric classes and adjust equations for diameter growth as a function of age for Cedrela fissilis in a Deciduous Seasonal Forest remain, located in the Descanso Municipality, Santa Catarina, southern Brazil. Thus, trees of this species were identified by transects and 30 sample plots were selected, taking into consideration the Cedrela fissilis as the center of the plot. The floristic and phytosociological parameters, soil and nondestructive samples of trunks of sample-tree of Cedrela fissilis for dendrochronological analysis were collected and evaluated. Ninety-four species distributed in 33 botanical families were observed, however 33 species have timber value. The Shannon Diversity Index was 3.96 and three subareas were differentiated by soil and frequency of species of the remain. The growth rings of sample-tree were identified, measured and submitted to cross-dating. A chronological period from 1844 to 2012 was obtained. The Tukey test (? ? 0.01) indicated homogeneity of annual increments of sample-trees in the study area. Mitscherlich, Gompertz, Weibull and Schumacher mathematical models were adjusted to estimate diameter growth as a function of age. The Schumacher model supplied the best accommodation for the data behavior and characteristics of this species. The ages 42 years and 82 years, respectively, diameter and basal area increment, were indicated as the most appropriate moments to make interventions for Cedrela fissilis in the remain studied under conditions of management. The passage time of this species between diametric classes increased significantly with the decrease of diameter increment, reaching 35 years for the last class. Therefore, the results of this study indicate that the remain studied has a high diversity, including species of timber value, supplying opportunities for exploration in the medium term. The dendrochronology showed applicability as a tool to contribute to sustainable management of this species and of the Deciduous Seasonal Forest in the west side of Santa Catarina state.