Resumo

TAMARIT-URIAS, Juan C. et al. Dynamic site index equations for Tectona grandis at Campeche, Mexico. Agrociencia [online]. 2014, vol.48, n.2, pp.225-238. ISSN 2521-9766.

A dominant height growth model and corresponding site index expression, allows estimating the productivity of forests stands and helps define the silvicultural management regime. The aim of this study was to develop, using data from permanent plots, a base-age invariant growth model for dominant height for Tectona grandis L. f. (teak) plantations at Campeche, Mexico. The base growth models used were those of Korf, Chapman-Richards and Hossfeld IV, which were reformulated as generalized algebraic difference equations to define the best site index structures. They were fitted under least squares with a data structure of non-overlapping pairs. To estimate the dominant height growth and classify plantation productivity, the dynamic equation type Chapman-Richards was selected based on the goodness of fit and similarity between the pattern of growth curves and observed trends. To improve the accuracy of the estimates this equation was fitted as a mixed effects model, correcting for heteroscedasticity and autocorrelation. The selected model is flexible and describes a pattern of polymorphic curves with multiple asymptotes, desirable characteristic to model a wide variety of growth patterns. Three specific growth patterns for the analyzed planting sites were detected.

Palavras-chave : teak; asymptotic polymorphism; growth rate; productivity classification.