摘要
随着黄石市青山湖3~#湖清淤工程的结束,针对清淤及3~#湖自身特点,分别考察了清淤前后水体中COD、TP、TN和重金属含量的变化,以及湖区表层底泥和湖南侧、湖北侧、湖沿岸沉积柱中重金属空间分布及垂向层序特征。结果表明,清淤后除COD和Zn明显升高外,TN、TP、Cu、Cd、Pb、Cr平均去除率分别达到52%,68.5%,86.87%,9.21%,10.56%,42.11%。通过地质累积指数法与潜在生态危害指数法评价表明,除Cd的生态危害属于极强级别外,Cu、Zn、Pb、Ni均属于轻微生态危害级别。整体而言,清淤后湖泊底泥表层重金属含量比清淤前明显降低,并在过渡层中随深度增加而降低,但变化趋势不大。因此,3~#湖1期清淤工程已经清除了3~#湖底泥中的污染层,平均清淤深度为80 cm相对合理,取得了预期的效果。
After Qingshan NO. 3 Lake dredging project was completed,the content variation of COD,TN,TP and heavy metals in water before and after dredging was studied,and spatial distribution of heavy metals and vertical sequence characteristics in sedimentary columns were investigated,according to the characteristics of Qingshan NO. 3 Lake. The results showed that,except obvious increase of COD and Zn,the average removal rate of TN,TP,Cu,Cd,Pb,Cr were respectively 52%,68. 5%,86. 87%,9. 21%,10. 56%,42. 11% after dredging. According to the geo- accumulation and potential ecological risk index,the results indicated that,except Cd with extremely strong ecological harm,Cu,Zn,Pb,Ni all had slight ecological hazard. On the whole,the concentration of heavy metals after dredging decreased more significantly than before,and reduced with depth in the transition layer,but the reduce trend was not obvious. In all,the pollution layer of lake had been eliminated in this dredging project,and it was relatively reasonable that the dredging depth reached to80 cm,thus the expected results had been achieved.
出处
《湖北理工学院学报》
2016年第3期16-21,共6页
Journal of Hubei Polytechnic University
基金
湖北省科技支撑计划项目(项目编号:2014BHE0030)
关键词
青山湖
底泥清淤
清淤深度
重金属
Qingshan lake
sediment dredging
dredging depth
heavy metals
