Modelagem da biomassa e do estoque de carbono em plantas jovens de Eucalyptus

Abstract

The aim of the present research was to test regression models in order to estimate the dry biomass and total carbon storage according to genetic material and age in Eucalyptus, at different initial development stages of the plant. The experiment was conducted with genetic materials of Eucalyptus, in which Eucalyptus urophylla, Eucalyptus grandis and Corymbia citriodora came from seeds and GG100, AEC144, 7085 and 58 were clones. Plants were evaluated before plantation, at two, four, six, eight and 12 months. The diameter at collar height and the length of the aerial part of the plant were obtained in all ages. The biomass of each plant was separated in bulk, leaves and root, and each compartment was dried in stove in order to determine the dry mass and total carbon. The content of elementary carbon was determined by part of the plant, as well as the basic density of the bulk. In order to estimate the dry biomass and total carbon per genetic material and age, non-linear models and simple and multiple linear models were tested. The characteristics evaluated on the plants tended to increase with age, and a typical behavior was observed according to the genetic material. Models fitted for different genetic materials and ages presented, in general, good adjustment and precision. When adjusting regression models each genetic material and age presented a singular behavior of dry biomass production and total carbon storage, thus it was not possible to select a common model that represented all of them. Differences identified in the production of biomass of genetic materials of Eucalyptus in the first year suggest the possibility of selecting genotypes for distinct conditions of plantation