城市内河沉积物对水体污染修复的影响研究

Influence of sediment in city river on water pollution restoration

研究了城市内河污染沉积物在污染源控制和河道水质修复达到一定程度后对河道水质的影响 .结果表明 :河道水质在净化后 ,保持一定的溶解氧 ,可有效抑制沉积物中有机物、氨氮和磷的释放 ,疏浚底泥并不是消除内河污染的必要条件 ,否则由于底泥缺氧释放 ,氨氮明显回升 ,而有机物不会很快上升 ,反而因反硝化消耗碳源继续有所下降 ;由于反硝化过程产生碱度使水体pH略有升高 ,更接近中性 。

When the pollution source had been controlledand the water quality had been restored partly the influence of polluted sediment on river water quality was studied. The result showed that, after the river water is purified, keeping high dissolved oxygen concentration may control the release of organic matter, ammonia and phosphorus effectively, So dredging is not the necessary condition to eliminate the river pollution. Otherwise, ammonia increases, but organic matters decreases because of denitrifation which consume carbon source. Alkaline produced in the process of denitrification can make pH increase and more phosphorus release can be restricted.