再悬浮条件下底泥对磷固定作用的研究

STUDY ON THE PHOSPHORUS IMMOBILIZATION ON SEDIMENTS UNDER THE CONDITIONS OF SEDIMENTS RE-SUSPENSION

通过室内模拟试验,研究了底泥再悬浮对磷的强化固定作用。结果表明:底泥再悬浮促进了磷由上覆水向底泥的迁移,并且强化了底泥对磷的固定作用.底泥曝气与机械搅拌使内源磷释放量从618.51mg·kg-1分别降至424.99mg·kg-1和581.55mg·kg-1.底泥再悬浮对易释放态磷向难释放态磷转化具有显著的促进作用,铁结合态磷小幅度下降,而钙结合态磷显著增加,其余赋存形态磷变化不显著.说明底泥再悬浮对磷的固定机理可能是易释放态磷向难释放态磷的转化.

The phosphorus immobilization on sediments was studied under the laboratory conditions with sediments re-suspension. The results showed that the phosphorus migration from overlaying water to sediments and the phosphorus immobilization on sediments could be enhanced by sediments re-suspension. The phosphorus release could be decreased from the original amount of 618.51 mg·kg^-1 to 424.99mg·kg^-1 by aerating to sediments and 581.55mg·kg^-1 stirring with the stirrer respectively. Sediments re-suspension would enhance obviously the phosphorus transformation from mobile forms to refractory forms. The Fe bound phosphorus was decreased, while the Ca bound phosphorus was increased and other phosphorus forms was kept stable in the sediments after re-suspended. It could be concluded that the mechanism of phosphorus immobilization onto sediments might be the phosphorus transformation from mobile forms to refractory ones under the conditions of sediments re-suspension.