Immobilization of phosphorus in lake sediments and control of internal-loading phosphorus release have become crucial aspects of eutrophication lake management. In this study, the immobilization efficiency of phosphorus by ferric chloride in Dianchi Lake sediments was investigated. In addition, effects of the dosage of ferric chloride and contact time on the release of phosphorus from sediments were investigated. Laboratory experiments revealed that ferric chloride can effectively inhibit the release of phosphorus from sediments. At a ferric chloride dosage of 10 mg/g, the total phosphorus concentration of the overlying water was reduced by ~87%. With the increase in the contact time, the amount of phosphorus immobilized by ferric chloride increased. To further evaluate the feasibility of ferric chloride for immobilising phosphorus in sediments, an amplification experiment with a water volume of 50 L was carried out. By the addition of 6 mg/g of ferric chloride, the total phosphorus concentration of the overlying water was still less than 0.01 mg/L after 100 days. At the same time, the phosphorus species in the sediment after treatment with ferric chloride were analyzed. Results revealed that ferric chloride mainly converts unstable exchangeable phosphorus (Ex-P), ferric phosphate (Fe-P) and organic phosphorus (Or-P) into more stable occluded phosphate (O-P), reducing the possible release of phosphorus from sediments. Practical applications of ferric chloride to control the release of phosphorus from Dianchi Lake sediments were discussed.

中文翻译：

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氯化铁对滇池沉积物中磷固定化和形态形成的影响。

湖泊沉积物中磷的固定化和内部负荷磷的释放控制已成为富营养化湖泊管理的关键方面。本文研究了氯化铁在滇池沉积物中对磷的固定作用。此外，研究了氯化铁的用量和接触时间对沉积物中磷释放的影响。实验室实验表明，氯化铁可以有效抑制沉积物中磷的释放。氯化铁用量为10 mg / g时，上层水的总磷浓度降低了约87％。随着接触时间的增加，氯化铁固定的磷含量增加。为了进一步评估氯化铁固定磷在沉积物中的可行性，进行了水体积为50 L的扩增实验。通过添加6 mg / g的氯化铁，100天后上层水的总磷浓度仍小于0.01 mg / L。同时，分析了氯化铁处理后沉积物中的磷种类。结果表明，氯化铁主要将不稳定的可交换磷（Ex-P），磷酸铁（Fe-P）和有机磷（Or-P）转化为更稳定的闭塞磷酸盐（OP），从而减少了磷从沉积物中的释放。讨论了氯化铁控制滇池沉积物中磷释放的实际应用。100天后，上层水的总磷浓度仍小于0.01 mg / L。同时，分析了氯化铁处理后沉积物中的磷种类。结果表明，氯化铁主要将不稳定的可交换磷（Ex-P），磷酸铁（Fe-P）和有机磷（Or-P）转化为更稳定的闭塞磷酸盐（OP），从而减少了磷从沉积物中的释放。讨论了氯化铁控制滇池沉积物中磷释放的实际应用。100天后，上层水的总磷浓度仍低于0.01 mg / L。同时，分析了氯化铁处理后沉积物中的磷种类。结果表明，氯化铁主要将不稳定的可交换磷（Ex-P），磷酸铁（Fe-P）和有机磷（Or-P）转化为更稳定的闭塞磷酸盐（OP），从而减少了磷从沉积物中的释放。讨论了氯化铁控制滇池沉积物中磷释放的实际应用。磷酸铁（Fe-P）和有机磷（Or-P）转变为更稳定的闭塞磷酸盐（OP），减少了磷从沉积物中的释放。讨论了氯化铁控制滇池沉积物中磷释放的实际应用。磷酸铁（Fe-P）和有机磷（Or-P）转变为更稳定的闭塞磷酸盐（OP），减少了磷从沉积物中的释放。讨论了氯化铁控制滇池沉积物中磷释放的实际应用。