Resposta à adubação e espaçamento de duas espécies florestais para produção de energia na Amazônia Central

Abstract

The Sclerolobium paniculatum belonging to the Fabaceae family, has good adaptation to more sandy and poor in nutrients. Belonging Myrtaceae Eucalyptus urograndis occurs in different environmental conditions, soils with high and low fertility. The objective of this research was to evaluate the growth of Eucalyptus urograndis and Sclerolobium paniculatum under different spacings and levels of phosphate fertilization on energy production in Itacoatiara-AM. 45 installments, with surround 18 et 10 useful plants / plot were deployed. The design was split plot in blocks. We determined the death rate; growth in height, diameter and volume; production and adjustment of regression models for biomass; stacking factor and characterization of wood for energy production. The conclusion for S. paniculatum that there was no influence of the spacing factor, serum phosphorus and interaction on growth in diameter, height and volume of the species. The amount of phosphorus influenced biomass production. Considering all spacings, the quadratic model of the volume as a function of dose (V = 72.4186 + 1,2225D - 0,0076D² - R² = 0.9484) was the best fit to the data with maximum point P = (73,85g, 113.87 m3/ha). The spacing of 2m x 2m was the one who showed regression of volume due to the dosage (V = 86, 5475 + 1,9047D - 0,0142D² - R² = 0.9991) with maximum point P = (60,07g, 149 72 m3/h). The biomass values was greater in the shank (25.64 kg) and the water content in leaves was higher (50.59%). The biomass showed significant results only for the dosage factor, with the highest production of 90g (85.56 Mg/ha) and 60g (81.96 Mg/ha). Considering all the spacings model that best fit the data of biomass as a function of dose was Biom = 46.6273 + 0,9839D - 0,0065D² - R² = 0.9676, with maximum point P = (75,68g, 86,83 Mg/ha). Only there was regression to biomass at 2m x 2m spacing, Biom = 49.6725 + 1,8226D - 0,0137D² - R² = 0.9804, with point P = (66,45g, 110.16 Mg/ha). The stacking factor was 0.63, the average basic density was 0,61g/cm3 and the moisture content of 80.54%. The best fitted model for aboveground biomass was given by equation Ps = -0,091850d + 0,424990d², with adjusted R² of 94.28% and 11.13% of Syx. Based on the calorific value of the wood species S. paniculatum was considered favorable for the production of energy. The conclusion for E. urograndis the amount of phosphorus significantly influenced the mortality rate, growth in height, diameter and volume production. Considering all the spacing, the ratio between the volume and the amount of phosphorus is linear, V = 18.5657 + 1,3367D, R² = 0.9768. There regression between the dose and the volume of phosphorus in the three spacings tested. The interaction factor dose of phosphorus and spacing was significant as well, spaced 2m x 2m doses of 90g and 120g not differ and show efficient. Considering all the spacings model that best fit the data of biomass depending on the dosage was Biom = 8.1120 + 0,7204D - R² = 0.9885. There was regression between biomass and the amount of phosphorus for the three spacings tested. The stacking factor was 0.64, the average basic density was 0.46 g/cm³. The moisture content showed significant results only for the dosage factor at doses of 120g (97.60%) and 90g (104.40%) higher than the other. The best fitted model for aboveground biomass was given by equation LNPS = - 2.252810 + 2,419040Lnd, with adjusted R² of 94.49% and 4.76% of Syx. Based on the calorific value of the wood species E. urograndis was considered favorable for the production of energy.