Anthropogenic activities have significantly enriched P in sediments of many water bodies, with redox potential (Eh) being a key factor in controlling P adsorption or release.This study evaluates the impact of Eh on P release from sediments in the Weiyuan River, Honghu Lake, and Bao'enqiao Reservoir using reactor experiments. P speciation was further analyzed through SEDEX method. Results show that within an Eh range of −300 mV to +230 mV, more P is released from sediments into the water column. The P fractions CDB-P and Fe(II)-P exhibit the most significant changes, especially in reservoir sediments where ΔCDB-P (85.5 mg/kg) and ΔFe(II)-P (80.6 mg/kg) are the highest among the three water bodies, followed by lake sediments. Additionally, after redox oscillation, the EPC0 of lake and reservoir sediments increased to 16.2 and 18.8 times their initial values, respectively, significantly raising the risk of eutrophication.

中文翻译：

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氧化还原电位对不同水体沉积物磷释放的影响


人类活动使许多水体沉积物中的磷显着富集，氧化还原电位（Eh）是控制磷吸附或释放的关键因素。本研究评估了Eh对威远河、洪湖、和报恩桥水库采用反应堆实验。通过SEDEX方法进一步分析P形态。结果表明，在−300 mV 至+230 mV 的Eh 范围内，更多的P 从沉积物中释放到水体中。 P 组分 CDB-P 和 Fe(II)-P 表现出最显着的变化，特别是在水库沉积物中，其中 ΔCDB-P (85.5 mg/kg) 和 ΔFe(II)-P (80.6 mg/kg) 最高。三个水体，其次是湖泊沉积物。此外，氧化还原振荡后，湖泊和水库沉积物的EPC0分别增加至初始值的16.2和18.8倍，显着增加了富营养化的风险。