Some of the leguminous tree associated to fixing bacteria and micorrizal fungi have good development in degraded soils. Aiming to evaluate the influence of these species on soil fertility level, dry matter production and the nutrient contents of litter originated from these plants were measured during 1995. The rate of litter decomposition was evaluated by analysing the material collected in 1995 and 1996. Homogeneous stands of Caesalpiniifolia mimosa ('Sabiá'), Acacia mangium and Acacia holosericea established at the experimental station of the Embrapa at 4 m²/plant spacing were used. The Embrapa Agrobiology (Seropédica (RJ) - South latitude: 33º 49' 22º 45'; Longitude West of Greenwich: 43º 38' 43º 42'; quotas varying from 18 to 33 m). The annual mean production of litterfall was 10 Mg ha-1 for Mimosa caesalpiniifolia and 9 Mg ha-1 for both Acacia species.The leaves accounted for an average 64% of the litterfall of both Mimosa caesalpiniifolia and Acacia holoricea, and 70% of Acacia mangium. Reprodutive structures were the litterfall component with the highest nutrient content. Acacia mangium showed the highest nutrient translocation among plant parts and produced the poorest litter wich presented the lowest decomposition rate. Litterfal asssociated with 'sabiá' was the richest one in terms of nutrient accumulation. Different decomposition rates of litter of the tree species studied could be used as a good strategy in order to supply nutrient requirements of different crops introduced in agroforestry production systems and for the recovery of degraded lands.
leguminous trees; land reclamation; decomposition