Abstract:Decomposition of agriculture waste materials in the soil needed a long time. In this paper, a five years pot experiment combined Bowman-Cole sequential extraction to determine organic phosphorous fractionation with application four kinds of agricultural waste materials to explore the long-term dynamic change law of the forms of organic phosphorus in black soil. The treatments included pig manure (PM), maize straw (MS), leaf manure (LM), mushroom dreg (MD) and chemical fertilizer only (NPK). The results showed that compared with applying chemical fertilizer only, concentration of organic P (L-OP) of PM treatment was significantly higher and continually reduced in 5 years, concentration of MS and LM treatments achieved the highest levels after 3 years, 2 years respectively. Application of pig manure, maize straw and mushroom dreg increased concentration of soil moderately labile organic P (ML-OP). The concentration of ML-OP continue decreased in 5 years after application of pig manure, while other treatments increased. The concentration of soil moderately resistant organic P (MR-OP) significantly increased but decreased year by year after applying agricultural waste materials, including straw treatment which was always higher than the rest. Soil highly resistant organic P (HR-OP) began to decrease from 2 years~3 years after application of agricultural waste materials. Applied pig manure significantly improved the active organic phosphorus forms for long time, ?leaves could decrease the content of HR-OP and fewer influence on the rest of the forms, maize straw and mushroom dreg had the similar trends, maize straw tended to increase the L-OP and MR-OP but mushroom dreg tended to increase the HR-OP content. Application agricultural waste materials could activate steady-state organic phosphorus in different extents. But apply chemical fertilizer only promoted MR-OP transform into HR-OP.