Dredging and in situ adsorbent inactivation are two methods which are frequently used in eutrophic water bodies such as ponds, lakes and estuaries to control internal phosphorus (P) loading from sediments. However, their effects and modes on the control of sediment P loading has been seldom compared. In this study, a long-term sediment core incubation experiment in the field was undertaken to investigate changes in sediment P loading (P fluxes, supply ability and forms of P and transformation) comparing two remediation techniques, that of lanthanum-modified bentonite (LMB) addition or dredging to a control. A 360-day field investigation indicated that LMB addition more effectively reduced pore water P concentrations and sediment P fluxes than dredging in comparison with the control. On average, dredging and in situ LMB inactivation reduced the P flux by 82% and 90%, respectively relative to the control sediment. Whilst both the LMB inactivation and dredging can reduce the mobile P concentration, the impact of LMB in reducing mobile P was demonstrated to be more prolonged than that of dredging after 360 days. The P fraction composition in the LMB inactivated sediment differed significantly from the dredged and control sediment. Contrary to physical removal of dredging, chemical transformation of sediment mobile P and Al-P into Ca-P is the main function mode of LMB for sediment internal P control. Both LMB addition and dredging caused changes in the composition of sediment bacterial communities. Whilst LMB addition increased bacterial diversity, dredging temporarily reduced it. This study indicates that in situ inactivation by LMB is superior to dredging in the long-term control of sediment P loading.

疏and和原位吸附剂失活是富营养化水体（如池塘，湖泊和河口）中经常使用的两种方法，用于控制沉积物中的内部磷（P）含量。然而，很少比较它们对控制沉积物磷负荷的作用和方式。在这项研究中，我们进行了长期的泥沙核心温育实验，以比较两种改性技术（镧改性膨润土（LMB））对泥沙中磷负荷的变化（磷通量，供应能力以及磷的形态和转化形式）的影响。 ）添加或疏通到控件。360天的现场调查表明，与对照相比，添加LMB比疏dr更有效地降低了孔隙水P浓度和沉积物P通量。平均而言，疏and和相对于对照沉积物，原位LMB灭活分别将P通量降低了82％和90％。尽管LMB的灭活和疏both都可以降低移动磷的浓度，但是LMB在减少移动P方面的影响要比360天后的疏long更长。LMB灭活沉积物中的P组分组成与疏and沉积物和对照沉积物显着不同。与物理疏of相反，沉积物中的P和Al-P化学转化为Ca-P是LMB控制沉积物内部P的主要功能模式。LMB的添加和疏caused均引起沉积物细菌群落组成的变化。虽然添加LMB可以增加细菌多样性，但疏temporarily会暂时减少细菌多样性。这项研究表明，原位 在长期控制沉积物P负荷方面，LMB灭活优于疏ging。