河道底泥营养物质生态风险及其吸附/解吸特征研究

Study on Ecological Risk and Adsorption/Desorption Characteristics of Nutrients in River Sediments

河道黑臭底泥可持续向上覆水中释放营养盐,是河水富营养化的重要污染内源。研究底泥中有机质、氮和磷等营养物质的生态风险及其吸附/解吸特征,有助于城市黑臭河道的污染控制与生态修复。本研究于株洲白石港设置53个底泥采样点,分层采集了210个底泥样品。生态风险评价表明,底泥处于高生态风险水平,底泥对磷、氨氮的等温吸附符合Henry吸附模型,其与上覆水交换氮、磷营养盐的过程中会有营养盐释放的潜在危害。

The black and odorous sediment of the river channel can continuously release nutrients to the overlying water,which is an important internal source of pollution of river water eutrophication.Studying the ecological risks and adsorption/desorption characteristics of nutrients such as organic matter,nitrogen,and phosphorus in sediments is helpful for pollution control and ecological restoration of urban black and odorous river channels.In this study,53 sediment sampling points are set up in Baishigang River,Zhuzhou,and 210 sediment samples are collected in layers.The ecological risk assessment shows that the sediment is at high ecological risk level,and the isothermal adsorption of phosphorus and ammonia nitrogen by the sediment conforms to the Henry adsorption model,and in the process of exchanging nitrogen and phosphorus nutrients between sediment and overlying water,there will be potential hazards of nutrient release.