Efeito da idade e do sítio na densidade básica e produção de massa seca de madeira em um clone do Eucalyptus urophylla

Abstract

This study aimed to evaluate the age and site effects on wood basic density and dry mass production. One hybrid clone of Eucalyptus urophylla (GG 100) was used in the ages of four, five, six, seven, eight and nine years, from areas owned by Gerdau Florestal S.A. Company at the following locations (macro-sites): João Pinheiro, Montes Claros, Rio Pardo de Minas, Southern Minas Gerais and Três Marias, in Minas Gerais State, Brazil. Within each location, five trees were selected by subsampling (micro-sites), totaling 485 sampled trees. Discs were removed at 2%, 10%, 30%, 50% and 70% of the commercial height and one extra at DBH position. The basic density was determined according to NBR 11941 of ABNT (2003). The mean annual increment in dry mass was obtained by multiplying the average annual volume increment (MAI) with the basic density at 1.30 m height or the mean basic density. The results showed a significant effect of interaction between site and age in basic density and tree growth characteristics. The location that showed the best rainfall and the best growth of trees, Southern Minas Gerais, negatively affected the value basic density and positively the dry mass production of clone GG 100.