Rates of accumulation, decomposition and the NPK released by the leaf litter of perennial legumes

A study was made on the rates of accumulation. disappearance and NPK nutrie nts released by, the leaf litter of the legumes: Desmodium ovalifolum. Puer aria phaseoloides, Stylosanthes guianensis and the Neonotoma wightii/Macrop tilium atropurpureum association. The association produced the largest accu mulation (1866.3 g DM/m(2)) while the remaining species accumulated between 700 to 900 g DM/m(2). There were good fits to linear equations (R-2 0.93) between legume age and accumulated litter. All legume leaf litter disappear ed 210 days after dropping on the grassland and D. ovalifolium and P. phase oloides showed a faster decomposition (16% per month). The litter of the gl ycine/siratro association released more N (32.2 g/kg) than the other legume s (23.25 g/kg) while D. ovalifolium anti the glycine,,siratro association r eleased N (32.2 g/kg) than the other les; a greater amount of P (5.7 to 5.9 g/kg) than the remaining species (3.2 to 4.2 g/kg). On the other hand. K r eleased by the leaf litter of the legumes were low with an average of 2.2 t o 2.9 g/kg. Results show the importance of perennial legumes in the grassla nds to increase nutrient recycling dynamics through the leaf litter produce d. Further studies to determine the advantage of having legume mixtures to increase the accumulation of good quality leaf litter in the grassland are necessary as well as animal management practices that contribute to a long stability of the legumes in each system.