| 摘要: |
| 为了解渤海中部海域沉积物中重金属的污染状况，于2013年8月采集了渤海中部海域34个站点的表层沉积物，检测了Pb、Cd、Hg、Cu、Zn和As 6种重金属的含量，分析了Pb、Cd、Cu和Zn 4种重金属的空间分布特征，采用污染指数法和潜在生态风险评价法对其表层沉积物重金属污染状况进行评价。结果显示，渤海中部海域表层沉积物重金属含量较低，符合海洋沉积物质量(GB 18668-2002)Ⅰ类标准的要求。表层沉积物重金属的空间分布总体呈现由近岸向中心海域降低的趋势。Cu、Zn和Pb含量空间变化趋势比较明显，靠近渤海湾海域重金属含量高，离岸距离越远，重金属含量逐渐降低。Cd含量在靠近黄河入海海域最高，呈现自高值区向东西两边海域减小的趋势。各个站位的重金属单因子污染程度较轻，单因子污染系数均值大小顺序为Pb>Cu> Zn>As>Cd>Hg；重金属综合污染指数都小于5，表现为低污染水平。除1号站位的Hg单因子潜在生态风险系数为54.44之外，其他站位表层沉积物Hg、As、Cu、Zn、Pb和Cd的单因子潜在生态风险系数Eir小于40，范围为0.39~38.80，风险程度由高到低依次为Hg、Cd、As、Pb、Cu和Zn；其综合潜在生态风险系数小于150，范围为16.39~79.57。其中，1号站位综合潜在生态风险系数最高达到79.57。研究表明，此海域属于低潜在生态风险水平，风险指数高值区出现在唐山大清河口海域。 |
| 关键词: 渤海中部 表层沉积物 重金属 分布特征 潜在生态风险评价 |
| DOI：10.19663/j.issn2095-9869.20180925001 |
| 分类号: |
| 基金项目:农业农村部专项“渤海生态环境监测评估”(13-Q52201302)和中央级公益性科研院所基本科研业务费专项(20603022017005)共同资助 |
|
| Distribution Characteristics and Pollution Assessment of Heavy Metals in the Surface Sediments of the Central Region of the Bohai Sea During the Summer |
|
XU Yong1,2, JIANG Tao1, YANG Qian1, CUI Zhengguo1, ZHAO Jun1, QU Keming1
|
|
1.Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture and Rural Affairs, Key Laboratory of Fishery Resources and Eco-Environment, Shandong Province, Yellow Sea Fisheries Institute, Chinese Academy of Fishery Sciences, Qingdao 266071;2.College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100
|
| Abstract: |
| The Bohai Sea is a semi-enclosed bay with weak water exchange capacity and pollution levels that are increasing with the development of modern industry and agriculture. Heavy metal pollution has become an important factor, as it both directly and indirectly endangers human health. The release of heavy metals from sediments might significantly impact on the water environment and the ecological health of the sea. A survey of heavy metal content, distribution, enrichment, and pollution state of the sediments was conducted in August 2013 to determine the seas characteristics. The contents of Cu, Pb, Zn, and Cd in the surface sediment samples from 34 sites were measured, and the content and distribution characteristics of these heavy metals were studied. Single factor standard indices and potential ecological risk indices were used to evaluate the status of the heavy metal pollution and the degree of ecological risk. The results indicated that the average heavy metal content was low, and that all individual element contents were lower than the first class of GB 18668-2002. The spatial distribution of the heavy metals in the sediments showed that their contents decreased between the offshore and central regions. The Cu, Pb, and Zn surface sediment heavy metals, showed the most obvious changes with relation to their location; their coastal content was higher and was gradually reduced in samples moving towards the offshore region. The Cd content in the Yellow River estuary was high to the east and decreased along the western sides. The individual single-factors for each of the heavy metals in the surface sediments was less than 5, which indicated a low degree of pollution, and the descending order of the average single factors was Pb, Cu, Zn, As, Cd, and Hg. The single potential ecological risk factor of the six heavy metals, except for the Hg element at No. 1 (54.44) station, were less than 40 (0.9~38.80), which indicates a low level ecological risk. The descending order of the potential ecological risk factors was Hg, As, Cu, Zn, Pb, and Cd, and ranged from 0.58 to 10.50. The comprehensive potential ecological risk indices are all less than 150, and ranged from 16.39 to 79.57, which indicated low level of ecological risks. The descending order was Hg, Cd, As, Pb, Cu, and Zn. The Daqinghe River estuary had the highest risk values, and Hg was the main potential ecological risk factor in the surveyed area. |
| Key words: Central Region of the Bohai Sea Surface sediment Heavy metals Distribution characteristics Potential ecological risk assessment |
