Efeito da aplicação de nitrogênio na produção e qualidade da madeira e carvão vegetal de um híbrido de Eucalyptus grandis x Eucalyptus urophylla

Abstract

The present work aimed to verify the effect of different dosages of nitrogen on the production of dry material, and wood and charcoal quality made from a six years old hybrid clone of Eucalyptus grandis x Eucalyptus urophylla. Overall 40 trees were analyzed and five treatments in four blocks were studied, with two trees sampled per treatment within each block. Treatments consisted in the application of 0, 60, 120 and 240 kg.ha-1 of nitrogen (N) as ammonium sulfate in order to evaluate if the response to such compound was exclusively due to N. An additional treatment was applied with 120 kg.ha-1 of N as ammonium nitrate, totalizing five treatments. The tree growth, basic density, dry mass estimate, chemical and energetic composition of wood were evaluated, as well as physical, chemical and energetic characteristics of charcoal. The production of dry mass tended to increase with the nitrogen dosage applied. The effect of nitrogen dosage did not influence the basic density and energetic characteristics of charcoal, however the content of elemental nitrogen, total extractives and lignin of wood increased with nutrition. Such application did not influence the chemical and energetic characteristics of wood and charcoal.