Produção volumétrica bruta, rendimento e modelagem de madeira serrada de espécies comerciais da Amazônia

Abstract

Accurately estimates of commercial volumetry are indispensable for management in enterprise-scale management plans. In this thesis, we tried to describe in a technical and objective way the state of the art of the production of commercial wood for the production of logs and sawn timber. In Chapter 1, we sought to provide reliable alternatives to estimate the commercial volume of trees in different forest types in Amapá, extreme north of Brazil. Benefiting from a large-scale inventory of fallen trees throughout the state of Amapá, specific volumetric models were developed for each type of vegetation as well as a generic equation, as well as determination of the specific form factor for each area. After estimating the volume of commercial timber by the models for each area, volumetric predictions were made using the generic equations and the local form factor for Fleet live tree inventory data to evaluate discrepant rates of volume estimation in total area and typology levels. In general, equations for different areas are fundamental to guide the production of wood in management plans in the Amazon. To achieve reliable volume estimates, specific equations at the ecological group level, families, diameter classes and commercial species are recommended considering different forest typologies in Amapá and Amazon. The form factor overestimates the commercial volumetric production and is not recommended for the predictions. In the chapter 2, a study was carried out on the production of sawn wood of commercial species in Amapá. In this chapter, the objective was to obtain and analyze the coefficient of volumetric yield for ten commercial tree species and to test the variation among species and by diameter classes. The data were obtained from a sawmill located in Porto Grande, Amapá, where the volumes, diameter and length of 50 logs of the species: Carapa guianensis, Dinizia excelsa, Hymenolobium petraeum, Dipteryx odorata, Goupia glabra, Handroanthus albus, Hymenaea courbaril, Ocotea rubra, Manilkara huberi e Vochysia guianensis. After the logs were split, the lumber volumes were quantified, and the volumetric yield coefficient was obtained. Thus, the general yield obtained for the sawmill (43.95%) as well as the yield of each species is within the established standards for the operation of the industry according to the legal requirements. The lowest value was obtained for Carapa guianensis (37.80%), while Hymenolobium petraeum and Dinizia excelsa generated higher values of wood utilization (54.41% and 54.40%, respectively). The species Hymenolobium petraeum, Dinizia excelsa, Ocotea rubra and Vochysia guianensis show a difference (p  0.05) in yield for the other species due to the higher values obtained, however they are similar (p  0.05) when compared to each other. There were no differences (p  0.05) in the diameter classes for the species, except for Handroanthus albus and Dinizia excelsa. However, there was no linear increase (p  0.05) between the diameter and yield of sawnwood for all species. In Chapter 3, an approach was taken on the estimated lumber volume for the commercial species described in the previous chapter. In this way, equations were generated from the fit and selection of 16 statistical models. In summary, precise estimates of lumber volume can be obtained by model 16 for C. guianensis. For D. excelsa and H. petraeum the models 13 and 15 are the most recommended, respectively. The model 7 presented the best adjustments for H. courbaril and V. guianensis. The models 5, 10, 11, 14 and 12 are the most suitable for D. odorata, G. glabra, M. huberi, O. rubra and H. albus respectively. Equations using only the log diameter variable suggest estimates with less precision. Also, the volume of the log should be considered as an important predictor variable for the obtaining of serrated volume for the different Amazonian commercial species.