扰动强化河道底泥对磷持留能力的研究

Enhancement of Disturbance on Phosphorus Immobility of River Course Sediments

以城市河道上覆水和底泥为材料,研究了扰动对底泥持留磷能力的强化作用,并分析了强化机理。结果表明,底泥扰动促进了上覆水中磷向底泥中迁移。与对照试验相比,溶解性磷酸盐(DIP)和总磷(TP)平衡浓度分别降低了73.02%和42.39%;与原底泥相比,扰动试验底泥中溶解性磷酸盐(DIP)的释放量降低了173.77mg·kg-1,对照试验底泥中DIP的释放量基本保持一致。另外,底泥扰动后,钙结合态磷(Ca-P)含量显著增加,并接近总磷的增加量;而对照试验底泥中,总磷的净增加量比较均匀地分配到弱吸附态磷(NH4Cl-P)、铁结合态磷(Fe-P)、钙结合态磷(Ca-P)中。

The enhancement of disturbance on phosphorus immobility of the sediments was investigated and the mechanism of phosphorus immobility was discussed, using overlying water and sediments from city river course as materials. Results showed that sediment disturbance could promote the migration of phosphorus from the overlying water to sediments. The equilibrium contents of DIP and TP were reduced by 73.02% and 42.39%, respectively, compared with the control experiment. Compared with the raw sediment, the accumulative release of DIP was reduced by 173.77 mg .kg^-1 in the disturbed sediments, while the content kept relatively constant in the control. Moreover, the net increase of Ca-P increased obviously in the disturbed sediments, and it is almost equal to the net increase of TP in the sediment. On the other hand, the net increase of TP in the control was distributed basically uniformly to NH4Cl-P, Fe-P and Ca-P.