STUDY ON THE NUTRIENT CYCXING OF AGROFORESTRY ECOSYSTEM

On the basis of the data obtained from a lot of field experiments, the litter and its decomposition in a farmland shcltcrbclt network ecosystem with Popahis tomendost Carr. were studied. Tt is estimated that the annual Utter of the system was 0. 55t/ha with return rate of 35. 7%. The weight loss rates of litter in the farmland in 180, 360 and 540 days were 30. 5% ,54. 7% and 75. 2%, respectively, and its annual decomposition rate was 0. 86. Moreover, the decomposing rate of selected nutrient elements was in the order of N>P>K>Mg>Mn>Ca.