宿州市沱河城市景观河流重金属富集及污染评价

为探讨宿州市景观河流底泥重金属的富集和污染状况,采集沱河景观河流底泥样品37个,测定了V,Cr, Zn, Pb, Cu和As等重金属元素的含量.运用污染负荷指数法、富集因子法评价了沱河底泥重金属的污染和富集程度,并利用因子分析法对重金属来源进行识别.结果表明:1)沱河底泥重金属除V和Cr外,Cu, Zn, Pb和As元素值均高于安徽省土壤背景值;污染负荷指数(P_(LI))变化在0.64～1.87之间,均值为1.24,属中度污染.2)富集因子表明重金属污染顺序由大到小为Cu, As, Zn, Pb, Cr, V.其中,Cr和V属轻度富集;其余元素为中度富集.3)因子分析显示各元素在显著性水平下成正相关关系.第一因子主要有Cu, Zn, Pb, Cr和V.Cr和V来源受到人为活动和自然母质共同作用;Cu, Zn, Pb主要来源于工业生产和交通.第二因子主要是As元素,其来源应该为煤炭等化学燃料的燃烧.可见,宿州市沱河景观河流底泥受到了一定程度的重金属污染,尤其是Cu和Zn,研究结果对于宿州市沱河环境治理具有一定的参考价值.

Enrichment and contamination evaluation of heavy metal of urban landscape river of Tuo River in Suzhou city

In order to investigate the accumulation and contamination of heavy metals in the sediment of landscape river in Suzhou City. 37 sediment samples were collected and the contents of heavy metal of V, Cr, Zn, Pb, Cu and As were determined from the Tuohe landscape river. Assessment of enrichment and contamination degree of heavy metals was conducted by pollution load index method and enrichment factor method in Tuohe sediment, and the sources of heavy metals were identified by factor analysis. The results showed that: 1) except for V and Cr, the other elements were higher than the soil background values of Anhui Province, and the pollution load indexes(P_(LI))ranged from 0.64 to 1.87 with an average value of 1.24, indicating moderate pollution according to classification criteria. 2)The order of the enrichment factor of heavy metals was Cu, As, Zn, Pb, Cr and V. Among them, Cr and V belonged to slight enrichment, and Cu, Zn, As and Pb belonged to moderate enrichment. 3)The results of factor analysis revealed that the correlation coefficients of six elements are positively correlated at the significance level, illustrating that they may have the same source. The first principal component factor are mainly controlled by Cu, Zn, Pb, Cr and V. Although the sources of Cr and V are disturbed by human activities, natural parent material is still the main source, and Cu, Zn and Pb mainly come from industrial production and transportation. The second principal component factor is mainly As, and its source should be the combustion of coal and other chemical fuels. In conclusion, the sediment of Tuohe Landscape river is polluted to a certain extent by heavy metals, especially Cu and Zn, and our results have some reference value for the environmental management of Tuo River in Suzhou City.