东平湖表层沉积物重金属的空间分布及污染评价  

Spatial Distribution and Pollution Assessment of Heavy Metals in the Surface Sediments of Dongping Lake

作　　者：张菊[1] 何振芳[1] 董杰[1] 邓焕广[1] 鲁长娟 郭娜[1] ZHANG Ju;HE Zhenfang;DONG Jie;DENG Huanguang;LU Changjuan;GUO Na(School of Environment and Planning, Liaocheng University, Liaocheng 252059, China)

机构地区：[1]聊城大学环境与规划学院,山东聊城252059

出　　处：《生态环境学报》2016年第10期1699-1706,共8页Ecology and Environmental Sciences

基　　金：国家自然科学基金项目(41401563);山东省自然科学基金项目(ZR2014JL028);中国博士后科学基金项目(2015M571830)

摘　　要：为了解东平湖沉积物中重金属的污染特征,于2013年11月环湖采集了44个表层沉积物样品,分析了Al、Cd、Cr、Cu、Fe、Ni、Pb、Zn、Hg、As、有机质的含量和粒度,采用克里格(Kriging)插值法探讨了重金属的空间分布特征,并采用富集因子法和潜在生态风险指数法对其进行了污染评价。结果表明:东平湖表层沉积物有机质的平均质量分数为22.4g·kg^(-1);平均粒径为25.5μm,以粘粒和粉粒为主;Cd、Cr、Cu、Ni、Pb、Zn、Hg和As的平均质量分数分别为0.299、78.7、43.8、37.3、22.4、100.0、0.030和17.3 mg·kg^(-1)。各重金属含量较高的区域主要位于大汶河入湖口即湖区的东部、东南部,其次位于南部湖区;Hg和As在湖区北部即出湖区部分区域含量也较高。以黄河干流沉积物化学元素的背景值为评价标准,Cd、Cu和Zn表现为中度污染,其他重金属元素为轻微污染;总体生态风险水平为中等,其中Cd和Hg是主要的生态危害因子,其对潜在生态风险指数的平均贡献率分别为46.5%和29.6%。大汶河入湖区和出湖区部分区域表层沉积物重金属具有强生态风险。Cd、Cr、Cu、Ni、Pb和Zn之间具有显著的正相关性,与受人类活动影响较小的Al和Fe亦呈显著正相关,结合其空间分布特征和污染水平,推断Cd、Cr、Cu、Ni、Pb和Zn的来源受到自然源和大汶河污染输入的双重影响;而Hg和As与其他重金属元素间的相关性不显著,其可能还来源于湖区的渔业养殖、化肥农药、垃圾和生活污水等面源污染,但具体成因仍有待进一步研究。In order to understand the pollution characteristic of heavy metals in the surface sediments of Dongping Lake, 44 surface sediment samples were collected from Dongping Lake in November 2013, and the concentrations of heavy metals (Al, Cd, Cr, Cu, Fe,Ni, Pb, Zn, Hg and As) and organic matter as well as the particle size of the sediment were analyzed. The Ordinary Kriging interpolation method was applied to interpret the spatial distribution characteristics of heavy metal concentrations. Using the concentrations of heavy metals in Yellow River sediments as the background, the pollution assessment was carried out by the enrichment factor method and the potential ecological risk index method. The results showed that the average organic matter content was 22.4 g·kg-1; and the surface sediments were mainly composed of clay and silt grain with an average particle size of 25.5 μm. The average concentrations of Cd, Cr, Cu, Ni, Pb, Zn, Hg and As were 0.299, 78.7, 43.8, 37.3, 22.4, 100.0, 0.030 and 17.3 mg·kg-1 respectively. In general, high concentrations of heavy metals were found in the inlet areas of Dawen River, i.e. the east and southeast areas of the lake, secondly in the south area of the lake. In addition, high concentrations of Hg and As were also found in part of the north areas which is near the outlet of the lake. The contamination of Cd, Cu and Zn were at the middle level, and the contamination of the others was low. The ecological risk of heavy metals in surface sediments was at middle level, in which Cd and Hg were the main ecological risk factors with average contribution ratios of 46.5% and 29.6%. Strong ecological risk was in surface sediments of the inlet areas of Dawen River and part of outlet areas of the lake. Cd, Cr, Cu, Ni, Pb and Zn were significantly positively correlated with each other, and also with Al and Fe which are generally less affected by human activities. Combining the above correlation analysis results with the spatial distribution characteristics and pollution levels of these metal

关 键 词：重金属 沉积物 空间分布 污染评价 东平湖 

分 类 号：X14[环境科学与工程—环境科学]