东平湖表层沉积物重金属的空间分布及污染评价

发布时间：2018-04-20 06:14

本文选题：重金属 + 沉积物　；参考：《生态环境学报》2016年10期

【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。
[Abstract]:In order to understand the pollution characteristics of heavy metals in sediments of Dongping Lake, 44 surface sediment samples were collected around the lake in November 2013. The content and particle size of organic matter were analyzed. The spatial distribution characteristics of heavy metals were studied by Kriging interpolation method. Enrichment factor method and potential ecological risk index method were used to evaluate its pollution. The results show that the average mass fraction of organic matter in surface sediments of Dongping Lake is 22.4 g / kg ~ (-1), the average particle size is 25.5 渭 m, and the average mass fractions of ZnHg and as are 0.299 ~ 78.7 ~ 43.837.322.4100.030 and 17.3 mg / kg ~ (-1) respectively. The regions with higher heavy metal contents are mainly located in the eastern part of the lake area, the southeast part of the lake area, and then in the southern lake area, where Hg and as content are also higher in the northern part of the lake area, that is, the part of the lake area out of the lake area. According to the background value of chemical elements in sediment of the Yellow River, CD Cu and Zn are moderately polluted, while other heavy metals are slightly polluted, and the overall ecological risk level is moderate, among which CD and Hg are the main ecological hazard factors. The average contribution rate to the potential ecological risk index was 46.5% and 29.6% respectively. There was significant positive correlation between heavy metals in the surface sediments of Dawen River entering the lake region and parts of the outcast region. There was a significant positive correlation between Pb and Zn in the surface sediments, and there was also a significant positive correlation between heavy metals and Al and Fe, which were less affected by human activities. Combined with its spatial distribution and pollution level, it is inferred that the sources of Pb and Zn of CdCrCrCuCuNIAN are affected by both natural sources and pollution input from the Davin River, but the correlation between Hg and as and other heavy metal elements is not significant. It may also come from fishery farming, chemical fertilizer and pesticide, garbage and domestic sewage pollution, but the causes are still to be further studied.
【作者单位】：聊城大学环境与规划学院;
【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)
【分类号】：X524;X824

【相似文献】