锁磷剂对流动水环境中沉积物磷形态的作用

Effect of phoslock on the phosphorus forms in sediments with fluxion water condition

如何控制水体沉积物中的磷含量,对于防治水体富营养化以及控制蓝藻水华具有重要的意义。通过在室内构建模拟河道,利用模拟水流不断冲刷沉积物,研究水流对不同形态磷的冲刷作用和添加锁磷剂对沉积物中各形态磷含量的影响、固定的效果。结果表明:(1)锁磷剂能减少沉积物中NH4Cl-P(NH4Cl可提取磷)含量,并且添加锁磷剂后水流冲刷对该形态磷削减效果较小。(2)添加锁磷剂使沉积物中BD-P(BD试剂可提取磷)含量先迅速升高后降低,沉积物中BD-P含量的最终降低使得该形态磷的释放风险减小,对沉积物起一定的整治作用。同时,水流冲刷对BD-P影响较大。(3)锁磷剂会与铝竞争吸附磷,使NaOH-rP(NaOH可提取无机磷)含量降低,导致NaOH-TotP(NaOH可提取无机磷和有机磷的总和)含量的降低。(4)锁磷剂使HCl-P(HCl可提取磷)含量升高,能有效降低沉积物磷释放风险。水流冲刷造成了沉积物中HCl-P含量下降。(5)在水流的冲刷作用下,添加锁磷剂使得沉积物中总磷下降速率低于未添加锁磷剂的沉积物,锁磷剂有助于沉积物中磷的稳定。这些表明,锁磷剂在控制河流沉积物内源磷的释放方面可发挥积极的作用。

Water eutrophication is a crucial problem in the whole earth. Phosphorus,which is a primary factor causing eutrophication,increases quickly in rivers and lakes in recent years. In this study,A simulated river was built in laboratory to investigate the effect of phoslock on phosphorus forms in sediments. In the simulated river,phoslock was added to lock phosphorus in its sediment. Running water continuously scoured the surface sediment to analyze the washing ability of water flowing on phosphorus forms. Concentrations of phosphorus forms were also detected after phoslock adding to assess the fixation of phosphorus by phoslock. The results displayed that： （1） phoslock could de- crease the content of NH4 Cl-P （NH4 Cl extractable phosphorus）, and there was smaller effect onphosphorus reduction when phoslock added. （2） The content of BD-P （BD extractable phosphorus） was rapidly increased firstly and then reduced,the reducing content of BD-P after phoslock added meant that the risk of phosphorus releasing was smaller. （3） When the phoslock was added,content of NaOH-rP （NaOH extractable inorganic phosphorus） and NaOH TotP （total NaOH extractable phosphorus） decreased. （4） When the phosloek was added, content of HCI-P （HCl extract- able phosphorus） increased. It could effectively reduce the risk of phosphorus release. The content HCbP decreasing was caused by water erosion. （5） Total phosphorus in the treatment added phoslock decreased more slowly that con- trol treatments under the flowing water,and indicating that the phoslock could be helpful to maintain the phosphorus stable. These results suggested that phoslock could play a positive role in the control of phosphorus releasing from sediments of some rivers. This will benefit to the decreasing of pollution stress of the rivers＇ receiving water systems.