| 摘要: |
| 通过海洋沉积物镉加标实验、沉积物间隙水分析和对加标沉积物毒性的10天底栖端足类生物检验,重点探讨在硫化物存在条件下,二价有毒金属镉在沉积物-间隙水系统中的地球化学分配和化学活性,及镉在沉积物中的化学活性与生物毒性间的关系。研究结果表明,镉加标沉积物的毒性与间隙水中镉浓度呈正相关,而与沉积物镉总量无关。在硫化物存在条件下,沉积物-间隙水系统中,二价镉在固、液两相间的分配主要受酸溶硫化物(AVS)影响。AVS归一化沉积物中二价镉含量可作为预测和评价二价有毒金属镉的化学分配行为和生物可获性或毒性的有效方法。酸解硫化物时同步提取的金属镉SEM Cd2+与AVS的摩尔浓度之比[SEM Cd2+]/[AVS]可用作评价缺氧状况下镉沾污沉积物的环境质量和毒性的判据。 |
| 关键词: 沉积物 间隙水 酸溶硫化物 镉 端足类 |
| DOI： |
| 分类号: |
| 基金项目:“九五”国家科技攻关资助项目96-922-01-02号 |
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| THE EFFECT OF ACID-VOLATILE SULFIDE ON GEO-CHEMISTRY CHARA CTERISTICS AND TOXICITY OF CADMIUM IN MARINE SEDIMENTS |
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WANG Ju-Ying, MA De-Yi, YAN Qi-Lun, CHEN Hong-Xing
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Institute of Marine Environmental Protection,State Oceanic Administra tion,Dalian,116023
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| Abstract: |
| In this study, the geochemical partitioning and chemical activity of toxic metal cadmium in a sediment-pore-water system, and the relationship between chemical activity and benthos toxicity of cadmium, were analysed in the marine sediment containing sulfides. A series of spiking experiments for sediments, pore-water analyses and 10d amphipod sediment toxicity tests were conducted in laboratory. We found that the toxicity of the sediment spiked with cadmium is correlated with concentration of cadmium in pore-water, but it is not associated with total cadmium added to the sediment. Partitioning of cadmium between solid and aqueous phases in the sediment-pore-water system is controlled by acid-volatile sulfide (AVS). AVS normalization of sediment cadmium concentrations can be used as an effective method to predict and assess the chemical partitioning behavior, bioavailability or toxicity of cadmium within sediments. The molar ratio of simultaneously extracted metal (SEM) cadmium to AVS, [SEM Cd2+]/[AVS], could be a useful indicator for assessing the benthic environmental quality and the toxicity of the anoxic sediment contaminated with cadmium. |
| Key words: Sediment, Interstitial-water, Acid volatile sulfide, Cadmium, Amphipod |
