淮河沉积物总磷和重金属沿程变化及污染评价

为了探究淮河沉积物中污染物的分布规律、来源及污染程度,于2014年7月沿淮河中下游设置16个采样断面,现场采样并检测沉积物中总磷(TP)质量比和重金属(As、Cu、Pb、Cd、Zn)的质量比,分析沉积物中污染物的沿程分布及来源并对污染状况进行评价。研究结果表明,淮河中下游沿程各城市下游断面沉积物中污染物平均含量比上游断面高;污染物来源分析表明,所有污染物均受到点源污染的影响,其中TP和Cu受到点源污染和面源污染的共同影响;单因子标准指数法对沉积物磷污染评价结果表明,淮河干流沉积物环境质量受磷的污染相对较轻;对重金属潜在生态危害程度分析表明,无论是单个重金属的生态危害程度还是综合生态危害程度都为轻微。

Variation and pollution evaluation of the total phosphorus and heavy metals in sediments of Huaihe River

To explore the pollution distribution, source and degree of the Huaihe River sedimentary, 16 sections along the midstream and downstream of the Huaihe River were sampled in July 2014. Then, the total phosphorus(TP)and heavy metals(As, Cu, Pb, Cd, and Zn)in the sediments were analyzed to explore the distribution of contaminants, source and pollution status. The results showed that the average content of pollutants in the downstream sections of main cities was higher than that of the upstream. The analysis of pollutant sources showed that all pollutants were affected by the point source pollution, while TP and Cu were polluted by both the point source pollution and non-point source pollution. The standard index method of a single factor was applied to evaluate the phosphorus pollution in the sediments. The results indicated that the environmental quality of sediments in the Huaihe River was less polluted by the phosphorus. The analysis on the potential ecological risk of heavy metals showed that both the ecological risk of the single heavy metal and the comprehensive ecological risk were slight.