Quantification of nutrient content in above-ground biomass of young Acacia mearnsii De Wild., provenance Bodalla

The present study deals with the quantification of the nutrient content of the Australian acacia (Acacia mearnsii De Wild.), provenance Bodalla, at the age of 28 months. The experiment is located at a site of low fertility of the AGROSETA company in Butia, Rio Grande do Sul (Brazil). Above-ground biomass components (leaves, living branches, dead branches, bark and wood) of nine sampled trees were analysed. The nutrient contents in the total biomass of Bodalla were 182 kg ha(-1) of N, 8.17 of P, 104 of K, 66.7 of Ca, 16.2 of Mg, and 10.1 of S. In total, 42.6% of the dry matter accounted for leaves and living and dead branches, which in turn account for 74% of N, 72% of P, 63% of K, 68% of Ca, 69% of Mg, and 74% of S of the above-ground biomass. In the trunk (bark and wood), which represents the remaining 57.4% of the total above-ground biomass, 26% of N, 28% of P, 37% of K, 32% of Ca, 31% of Mg, and 26% of S were accumulated.