通惠河某段沉积物污染特征研究与评价

Characteristics of Sediments Polluted by Heavy Metals in a Reach of Tonghui River

选取了通惠河高碑店-双会桥段的5个断面进行取样,对底泥重金属含量及重金属形态进行测定。结果表明,Zn和Pb主要以残渣态存在;Cu以具有活性潜力的铁锰氧化物形态及碳酸盐结合态2种形态为主;Cd的可交换态占其总量的比例较高,而其残渣态含量极小。采用地累积指数法、次生相与原生相分布比值法以及潜在生态风险指数法从不同角度对河道沉积物中重金属的污染风险进行了评价。地累积指数法的评价结果表明不同重金属的污染级别为Zn>Cu>Cd>Pb。次生相与原生相分布比值法的评价结果显示:不同重金属元素的潜在污染效应关系为Cd>Cu>Zn>Pb,而Hakanson潜在生态风险指数法评价结果显示潜在生态危害系数大致排序为Cd>Cu>Pb>Zn。

Speciation characteristics of heavy metals such as Cu,Zn,Cd and Pb in sediment of Tonghui River,Beijing were investigated and their potential risk to ecosystem was assessed respectively by Ige（oindex of geo-accumulation）,RSP（ratio of secondary phase and primary phase）and PER（potential ecological index）.The findings of the study indicated that degree of heavy metal pollution was Zn〉Cu〉Cd〉Pb,Potential contamination risk was Cd〉Cu〉Zn〉Pb and potential ecological index was Cd〉Cu〉Pb〉Zn.