沈阳西部污灌渠沉积物中污染物积累与生态毒性研究

沉积物样品采自沈阳西部污水灌渠的上、中、下游．进行了污染物(重金属和矿物油)含量分析和生态毒性试验．结果表明，所有沉积物中均有污染物的积累，矿物油含量在400～12500mg·kg^-1，重金属Cd为1．6～27．2mg·kg^-1．沉积物对植物和蚯蚓都有明显的毒性效应．种子发芽根伸长抑制率为10％～60％．蚯蚓试验14d和28d死亡率分别为0%～70％和0%～85％．体重增长抑制率为-21．9%～17．7％和-18．6%～37．0%．研究表明，长期污灌导致河道沉积物中污染物积累和较强生态毒性．沉积物作为重要的污染源，其污染物迁移与释放对地下水和土壤具有潜在危害．

Accumulation of pollutants in sediments and their eco-toxicity in the wastewater irrigation channel of western Shenyang

Sediment samples were collected from several sites in the upper, mid and lower reaches of the petroleum wastewater irrigation channel in western Shenyang of China, and the concentrations of their heavy metal Cd and mineral oil were determined. The results showed that pollutants were accumulated in all test sediments, with 400-12,500 mg x kg(-1) mineral oil and 1.6-27.2 mg x kg(-1) Cd. The sediments had significant inhibition effects on plant and earthworm. The inhibition rate of root elongation based on germination test was 10%-60%. During 14 d and 28 d exposure, the mortality rate of earthworm was 0%-70% and 0%-85%, and the inhibition rate of its body weight growth was -21.9%-17.7% and -18.6%-37.0%, respectively. It indicated that a long-term irrigation with wastewater resulted in the accumulation of pollutants in channel sediments and enhanced eco-toxicity. As an important source of pollution, the migration and release of pollutants in sediments possessed potential risks to underground water and soil.