底栖软体动物净化富营养化河水实验研究

Purification of Eutrophic River Water with Benthic Mollusks

文章研究了底栖软体动物(河蚌、螺蛳)富营养化河水中COD、NH3-N、TP、叶绿素a的净化效果。结果表明:⑴底栖软体动物对于富营养化河水中的COD、氮、磷等有一定的去除效果,且河蚌的净化效果要稍优于螺蛳;⑵曝气各组底栖软体动物对污染物的去除效果要明显优于非曝气各组;⑶非曝气实验组各项理化指标的去除效果同底栖软体动物的放养密度和处理时间相关;⑷停留时间为3d、曝气充氧、螺蛳和河蚌的放养密度分别为35个/m2～70个/m2和3个/m2～7个/m2时,净水效果最好;⑸河水中COD和叶绿素a含量呈现同步降低的规律,表明低等藻类是螺蛳及河蚌的主要摄食对象。

Purification effect of benthic mollusks including Anodonta woodiana and Bellamya aeruginosa on CODcr,NH3-N,TP and chl-a in eutrophic water body was investigated.Results showed that benthic mollusks had some purification effect on CODcr,NH3-N,TP and chl-a of eutrophic river water,and the effect of Anodonta woodiana was better than that of Bellamya aeruginosa.Aeration could obviously enhance the pollutant removal from river water.The purification effect without aeration had relationship to the density and treatment time of benthic mollusks.The best density and treatment time of benthic mollusks was 35~70/m2 for Bellamya aeruginosa or 3~7/m2 for Anodonta woodiana and 3days respectively.Simultaneous removal of chl-a and COD indicated that Anodonta woodiana and Bellamya aeruginosa mainly feed on low ranking algae under the experimental conditions.