Modelagem de crescimento em nível de árvore individual para plantios comerciais de eucaliptos

• Autor(a) principal: Martins, Fabrina Bolzan
• Data de Publicação: 2011
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/554
• topic: Eucalipto; Modelo de árvore individual; Modelo de crescimento e produção; Eucalyptus; Models at individual tree; Growth and yield models; CNPQ::CIENCIAS AGRARIAS::RECURSOS FLORESTAIS E ENGENHARIA FLORESTAL::MANEJO FLORESTAL

The empirical growth and yield models are composed of three ranks: at whole stand level, at diameter class level and at individual tree level. Among them, the models at individual tree level are the most complex because they use the tree as the basic modeling unit. In Brazil, studies involving these models are scarce, therefore showing great study potential. Thus, the objective of this work was to adjust a complete growth model at individual tree level for commercial plantations of eucalypt and to validate its use. For this purpose, five distance-independent competition indexes were evaluated (Chapter I); different models of probability of mortality were evaluated ad compared (Chapter II); different models of growth in diameter and height were evaluated and compared (Chapter III), and the complete model of growth at individual tree level was validated, adjusted to the other chapters (Chapter IV). To achieve these objectives, data from continuous forest inventory of unthinned hybrid clonal plantations of Eucalyptus grandis X Eucalyptus urophylla were used and these are from the Jari Celulose S/A enterprise, located at Monte Dourado (PA). Of the five competition indexes evaluated, the basal area index (BAI) showed the best performance to describe the competition among individual trees of eucalypt. This performance is due to the calculation simplicity and to the biological realism, since it combines variables of tree size and stand density. From the five models of probability of mortality analysed and compared, the West model was the one that obtained the best estimation because it produces a non linear response of the mortality probability in function of the competition index and because it has a less complex form and biological realism. Among the seven models of growth in diameter and height, the Lundqvist-Korf model was the one that produced the most accurate estimations, in relation to the statistics evaluated (R 2 , BIAS e Sy.x%) and the graphical analysis of residuals. The validation of the adjusted individual tree model, considering independent data to adjustment the equations, showed that model supplies accurate and consistent estimations for plantations in different conditions.