【摘要】 基于潮土长期定位施肥试验(19892~004),利用三种浸提剂(水、NaHCO3、Mehlich 3)和ICP-AES测定法初步研究了土壤可溶性有机磷的变化规律、有效性以及不同施肥措施对有机磷有效性的影响。结果表明,长期不施磷的处理,土壤可溶性有机磷的含量常年维持在本底的极低水平;施用有机肥明显增加可溶性有机磷的含量,有机肥与NPK配施次之,只施无机肥料增加的幅度相对较小;施磷而不施氮(PK处理)导致三种浸提剂提取的磷90%以上为无机态。水、NaHCO3及Mehlich 3浸提的有机磷占对应浸提总磷的比例分别为18.8%、14.5%和8.9%,这部分有机磷与作物地上部吸磷量、土壤有机质达到极显著正相关,表现出较高的有效性,在磷素贫乏的土壤中表现更为明显,是土壤有效磷库的重要来源。更多还原

【Abstract】 Based on the long-term(1989 to 2004) field fertilization experiment in calcareous fluvo-aquic soil with crop rotation of winter wheat and summer maize,three extractants(water,NaHCO3,Mehlich 3) and the method of ICP-AES were used to study the dynamics and availability of soil soluble organic phosphorus as well as the effect of different fertilization treatments on organic phosphorus availability.The results showed that: 1)Soil soluble organic phosphorus values maintained at the wondrously low level as background soil without applying phosphorus fertilizer;while soil soluble organic phosphorus contents increased significantly with the application of organic manure,followed by combined application of organic manure and inorganic fertilizer.However,application of inorganic fertilizer alone showed a relatively lower effect;2)Applying inorganic fertilizer phosphorus without nitrogen(PK)inorganic phosphorus accounted for more than 90% of total phosphorus extracted by three extractants;3)Water,NaHCO3 and Mehlich 3 extractable organic phosphorus accounted for 18.8%,14.5% and 8.8% of homologous extractable total phosphorus,respectively;4)Water,NaHCO3 and Mehlich 3 extractable organic phosphorus were positively correlated with accumulated phosphorus in the shoot of crops and soil organic matter,and showed high availability especially in phosphorus-sterile soils,which demonstrated that organic phosphorus was an important source of soil available phosphorus pools.更多还原