Biomassa, concentração e conteúdo de nutrientes em diferentes compartimentos de uma floresta secundária na Amazônia Oriental.

Abstract

With the objective to determine the biomass, the concentration and the content of nutrients in the different compartments (trees, sub-forest and liteira) of a secondary forest (capoeira) of approximately 15 years of pousio and enter the compartments of the trees (trunk, rind, twigs and leves), a comparative work in the Station of Piscicultura de Água was carried through Candy in Castanhal, Pará. It was characterized vegetation under álico yellow Latossolo, through a floristic inventory in 0,5 ha of the secondary forest, where ali the trees with diameter the height of the equal chest biggest and the 7cm had been identified and mensuradas. The floristic inventory presented a total of 429 greaters and equal individuais 7cm of diameter, represented for 40 species, 33 sorts and 21 botanical families. The botanical families who had occurred more frequently had been leguminosae (23,07%), annonaceae (14,68%), lauraceae (13,51%), lacistemaceae (13,05%) and flacourtiaceae (12,12%). The species that had presented greater frequency had been: Rollínia insignis (13,98%), Ocotea guianensis (13,05%), Lacistema pubescens Mart. Aggregatum (13,05%), Casearia arbórea Richjurb (10,72%), Inga a!ha (sw) wild (10,02%) and Abarana jupumba var. jupumba (8,85%). The biggest production of dry biomass in the compartments of the capoeira occurred in the trees. While that, in the compartments of the trees the biggest production was observed in the trunk. The biggest concentrations of nutrients in the compartments of the capoeira had occurred in the trees. In the compartments of the trees the biggest nitrogen concentrations had occurred in leaves, in the twigs and leaves one observed the biggest concentrations for phosphorus and potassium. While that in the rind the biggest concentrations of calcium and magnesium had occurred. In the trees the nutrients between the compartments of the capoeira had occurred the biggest contents of ali. It enters the compartments of the trees, the trunk presented the biggest contents of ali nutrients.