Energy estimate and carbon stock in short-rotation eucalyptus stands

Abstract

The use of biomass as an alternative energy source has been gaining attention because of its energy characteristics and environmental contribution and because it is renewable in short production periods. The aim of the present study was to evaluate the biomass production and carbon sequestration of eucalyptus grown under different conditions. The basic density of the wood, stem volume with and without bark and dry biomass, accumulated carbon, assimilated carbon dioxide and estimated energy for each shoot component were determined for two hybrid clones of E. grandis x E. urophylla at 6 and 12 months of age, grown at different spacing in two different areas, one with and one without irrigation. The highest dry biomass and carbon accumulation values were observed for plants grown at smaller spacing and with irrigation. A significant effect of irrigation on the variables quantified was only observed for 12-month-old plants. The amount of assimilated CO2 in the stem, leaves and branches was higher for 12-month-old plants grown at larger spacing and with irrigation. The estimated energy of the stem increased with increased spacing. Bark was the shoot component least influenced by spacing and irrigation.