广东省西伶通道内河航道底泥重金属污染状况与生态风险评价

Heavy Metal Pollution and Ecological Risk Assessment in Sediments of the Xiling Channel of Inland Waterway of Guangdong Province

利用珠江航道的西伶通道内河航道河流5个断面的底泥监测数据,运用内梅罗综合指数法、变异系数法、地累积指数法及潜在生态危害指数法分析评价了底泥的重金属污染状况。结果表明:Cr达到轻度污染;Cu的变异程度较大,Cr和Zn沿程变化明显,出现波动情况;各重金属富集水平为Cd>Cu>Cr>Zn>Pb>Ni>Hg>As,Cd的富集程度最高,属于偏中度污染;重金属生态危害大小为Cd>Hg>Cu>Pb>As>Cr>Ni>Zn,Cd的生态危害最强,是潜在生态风险的主要控制因子。研究表明,西伶通道内河航道底泥受到一定程度的重金属污染,主要污染为镉污染,潜在生态风险最大。

Based on the study of the sediment environment of the river channel in the Xiling channel, we used the Nemeru comprehensive index method, the coefficient of variation, the cumulative index method and the potential ecological hazard index method to further analyze and evaluate the heavy metal pollution of sediment. The results showed that the Nemero comprehensive index of Cr was 1.10, which was grade Ⅲ, and was mildly polluted;the coefficient of variation of Cu was 0.62, the variation degree was large, the changes of Cr and Zn was obvious, the fluctuation occurred;the enrichment of heavy metals decreased in the order: Cd>Cu>Cr>Zn>Pb>Ni>Hg>As, the accumulation of Cd the index ranged from 1.32 to 1.87, the enrichment was the highest, and it was partial pollution. The ecological hazard of heavy metal decreased in the order: Cd>Hg>Cu>Pb>As>Cr>Ni>Zn, the contribution rate of Cd to the potential ecological risk index ranged from 57.7% to 74.2%, the potential ecological hazard coefficient was as high as 135, the ecological hazard was the strongest and the main control factor on the potential ecological risk. Xiling channel inland waterway sediment was polluted heavy metals to some extent, the main pollutant was cadmium.