Nutrient cycling in eucalypt plantation systems allows for an evaluation of eventual differences due to the applied management methods and inferences on the sustainability of plantations. The aim of this study was to evaluate possible differences in nutrient cycling and balance in eucalypt plantation systems according to the species. Stands of Eucalyptus grandis, E. camaldulensis, and E. pellita were evaluated at the age of six years, in the Coastal Plains in the north of Rio de Janeiro State (Yellow Oxisol and Argisol) from April 1999 to December 2001. Soils under the forest species differed little in relation to fertility. The biomass production of all species was very low. The above-ground biomass of E. pellita (71.9 Mg ha-1) was superior to the other species. In all species, the largest biomass portion was allocated in the stem (87.92 %). In general, largest amounts of N, P and K were found in the wood and Ca and Mg in the bark. Ca was the nutrient with highest above-ground accumulation. The species differed little in the accumulation of nutrients. However, E. pellita was the species that showed highest efficiency in nutrient use. Results indicate the superiority of eucalyptus species in the intensity of biochemical and biogeochemical cycling and of nutrient balance.
Decomposition; litter; biomass; soil fertility; Eucalyptus spp
