Decomposition and nitrogen release patterns of Paraserianthes falcataria tree residues under controlled incubation

Tree legumes can serve as nitrogen (N) source for cereals in resource poor farms where chemical fertilizer is financially unaffordable. Despite the increasing importance of Paraserianthes falcataria in tropical agroforestry systems of Southeast Asia, little information is available on the decomposition and N release patterns of P. falcataria. Quality of P. falcataria roots and leaves, as individual components and as a mixture, was determined before incubating in an ^sup 15^N labeled acidic Ultisol under controlled laboratory conditions. Decomposition was monitored as CO^sub 2^ evolution and inorganic N released over time. The aim was to determine inorganic soil N and pH dynamics as affected by residue quality. Residue quality assessment based on (Polyphenol + Lignin): N was in the order of P. falcataria leaves > P. falcataria mixture of leaves and roots > P. falcataria roots. The same order was observed for nitrogen and carbon mineralization rate (P