中文摘要：

以重污染河道底泥和上覆水为材料，研究了周期性加入外源磷条件下，间歇扰动对底泥吸附和固定外源磷的作用机制．结果表明，扰动状态下，39d内底泥对外源磷的累积吸附量达到363．4mg·kg^-1，远高于静态试验（213．2mg·kg^-1）．内源磷形态分析表明，扰动状态下底泥吸附的外源磷中超过61％被结合到铁铝结合态磷（Fe／Al-P）中，而静态试验则上升为83％．考虑到Fe／Al—P的生物有效性，结合到非闭蓄态铁铝结合态磷中的外源磷分别占40．6％（扰动试验）和59．5％（静态试验）．另外，扰动状态下，超过23％的底泥吸附的外源磷结合到钙结合态磷（HCl-P），而静态试验中HCl-P基本保持不变．底泥吸附外源磷后，2种底泥磷最大吸附容量（Smax）均有所降低，而扰动后底泥的磷平衡浓度（EPC0）、磷饱和度P（％）的增加幅度明显低于静态试验底泥．因此推测，底泥扰动不仅可以加快底泥对磷的吸附，而且提高了内源磷持留能力．

英文摘要：

The mechanisms of phosphorus （P） adsorption and immobility were investigated in laboratory experiments. The sediments and waters used were taken from an inner-city heavily polluted canal. Addition of KHEPO4 into the operated experimental units,with and without （ i. e. , static） intermittent sediment resuspension, were made similar to the external P input and carried out periodically. The results show that the amount of the accumulative P adsorption onto the sediments was up to 363.4 mg·kg^-1 under the conditions of sediment disturbance over a 39-day period,and it was evidently higher than that （213.2 mg·kg^-1 ） under static conditions. Sequential fractionation indicated that most of the incorporated P was accounted for in the Fe/Al-P. There were over 61% in the case of intermittent sediment disturbance and up to 83% in the case of static conditions. Based on the bioavailability of Fe/Al-P,40.6% of the incorporated P was accounted for in non-occluded Fe/Al-P of the sediments under intermittent sediment disturbance conditions. This value increased to 59.5% under static conditions. In addition, more than 23% of the incorporated P was accounted for in HCl-P of the sediments under intermittent sediment disturbance conditions, on the other hand, the concentration of HCl-P kept relatively constant under static conditions. After 39 d of P adsorption by the both sediments, the values of the maximum sorption capacity （ Smax） decreased,while zero equilibrium P concentration （EPC0 ） and P saturation P（ % ） increased. However, the extent of EPC0 and P% under intermittent sediment disturbance conditions was obviously lower than that under static conditions. It was hopefully suggested that intermittent sediment disturbance can not only accelerate the P adsorption but also enhance the P retention by sediments.