于桥水库沉积物内源污染特性研究

Study on internal pollution of sediments in Yuqiao Reservoir

通过对天津市于桥水库沉积物中污染物的释放实验研究,找出了于桥水库底泥中磷、有机质、氮、铁、锰等污染物释放的影响因素,得出了溶解氧、pH值、水温等影响因素对底泥污染物释放的影响程度,并对各污染物的释放机理进行了探讨。磷的释放条件:pH值≥8时,好氧条件下会缓慢释放,当ρ(DO)<2 mg/L时快速释放;在中酸性条件下,当ρ(DO)<1 mg/L时发生较快速释放;低溶解氧和高pH值协同作用强烈。有机物和氮的释放主要受溶解氧浓度影响,与pH值关系不大,在ρ(DO)<2 mg/L时发生了快速释放。溶解性铁、锰的释放取决于水体pH值,在酸性条件下,ρ(DO)<1 mg/L时释放。

Factors affecting the release of phosphorus, organic matters, nitrogen, iron and manganese from sediment at Yuqiao Reservoir in Tianjin City were found out through experiment. The influence of DO, pH value, and water temperature on the release of pollutants was studied, and the mechanisms of pollutant release were discussed. Phosphorus was released slowly under the condition that pH ≥ 8 and dissolved oxygen was abundant; under the condition of pH ≥8 and p（DO） 〈2mg/L, or pH≤7 and ρ（DO） 〈 1 mg/L, phosphorus was released quickly. The synergistic reaction of low DO and high pH was intensive. Instead of pH, the release of organic matters and nitrogen was mainly affected by DO, and they were released quickly ff ρ（DO） 〈2mg/L. Dissolved iron and Manganese were released if ρ（DO） 〈 1mg/L and pH 〈 7.