Key Laboratory of Marine Hydrocarbon Resources and Environment Geology, Ministry of Land and Resources, Qingdao, 266071, China.
Environ Sci Pollut Res Int. 2015 Aug;22(15):11634-47. doi: 10.1007/s11356-015-4393-y. Epub 2015 Apr 7.
Spatial distribution, ecological risk, pollutant source, and transportation of trace metals in surface sediments, as well as the sediment properties, were analyzed in this study to assess the pollution status of trace metal in the Laizhou Bay, China. Results of provenance analyses indicate that surface sediments were primarily from weathering products carried by the surrounding short rivers and partially from loess matters carried by the Yellow River. Variations of trace metal concentrations were mostly controlled by the accumulation of weathering products, organic matters, and the hydrodynamics. Geoaccumulation index suggests that no Cr pollution occurred in the study area, and Cu, Pb, and Zn pollutions appeared only at a few stations. Comparatively, Cd and As pollutions were at noticeably weak to moderate level at many stations. The combination of six trace metals in this study had a 21% probability of being toxic in our study area based on sediment quality guidelines. Enrichment factors (EFs) and statistical analyses indicate that Cu, Pb, and Zn were primarily derived from the natural process of weathering. By contrast, Cd, As, and Cr (especially Cd and As) were provided by the anthropogenic activities to a large extent. Due to the dilution of coarse-grained sediments, there was even no contamination at some of stations that were obviously influenced by humans. Based on the current study of transportation process of fine-grained sediments in combination with the spatial distribution of EFs, it is found that the migration of anthropogenic trace metals was mainly controlled by the tide in the Laizhou Bay. The study suggests that an effective strategies and remedial measures should be designed and undertaken to prevent further anthropogenic Cd and As pollutions in this area in the future.
本研究分析了莱州湾表层沉积物中痕量金属的空间分布、生态风险、污染源和输运，以及沉积物性质，以评估该地区痕量金属的污染状况。物源分析结果表明，表层沉积物主要来源于周边短河流搬运的风化产物，部分来源于黄河搬运的黄土物质。痕量金属浓度的变化主要受风化产物、有机质和水动力的积累控制。地质累积指数表明，研究区无 Cr 污染，Cu、Pb 和 Zn 污染仅出现在少数站位。相比之下，Cd 和 As 污染在许多站位处于较弱至中等水平。基于沉积物质量基准，本研究中六种痕量金属的组合在研究区域有 21%的概率具有毒性。富集因子（EF）和统计分析表明，Cu、Pb 和 Zn 主要来源于自然风化过程。相比之下，Cd、As 和 Cr（尤其是 Cd 和 As）在很大程度上是由人为活动提供的。由于粗粒沉积物的稀释，即使在一些明显受人类影响的站位也没有受到污染。基于当前对细颗粒沉积物输运过程的研究以及 EF 的空间分布，发现人为痕量金属的迁移主要受莱州湾潮流控制。研究表明，应设计并采取有效策略和补救措施，以防止该地区未来进一步的人为 Cd 和 As 污染。
