Effect of the age on them stem form of Araucaria angustifolia in Central-Southern region of Paraná

• Autor(a) principal: Martins, Ana Paula Marques
• Data de Publicação: 2017
• Outros Autores: Machado, Sebastião do Amaral, Figueiredo Filho, Afonso, Corte, Ana Paula Dalla, Gorenstein, Maurício Romero
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Pesquisa Florestal Brasileira (Online)
• Texto Completo: https://pfb.cnpf.embrapa.br/pfb/index.php/pfb/article/view/1329
• topic: Diameter increment; Tree form; Forest mensuration; Crescimento em diâmetro; Forma da árvore; Medição florestal

The evolution of the stem form of trees in stands of Araucaria angustifolia (Bertol.) Kuntze was studied by means of taper functions and form factors. The data used were obtained by complete stem analysis and by rigorous scaling of standing trees in stands established in central-southern region of Paraná, with a sample of 45 trees. Four taper functions were adjusted for the total data set and for stratified data by classes of age. Tapering curves were constructed for different age classes. Model identity tests were performed to compare complete and reduced models. To assess the evolution of natural and artificial form factors, they were calculated for different ages, starting at 5 years old. Schöpfer´s polynomial was the selected model. There were significant differences among complete and reduced models with a slight advantage in the use of equations adjusted by age classes, as well as a significant improvement in the stem taper with the increase in age, also verified by the stabilization of the values of form factor at 22 years.