重金属对扁额细首纽虫金属硫蛋白的影响

生物体内金属硫蛋白含量变化,可作为环境中重金属污染的生物标志物.通过暴露实验研究了扁额细首纽虫Cephalothrix simula暴露在不同浓度的铜,锌和镉溶液96 h,其体内金属硫蛋白含量的变化规律.结果表明3种重金属离子的胁迫作用均导致金属硫蛋白含量增加,在实验初期(6～24 h),金属硫蛋白含量达到高峰;金属硫蛋白含量与暴露溶液金属浓度具有明显的剂量～效应关系,金属离子浓度越高,金属硫蛋白含量越高;锌离子诱导金属硫蛋白合成的作用大于铜、镉离子.     

Study on the Adsorption of Metal Ions by Immobilized Marine Algae with the Existence of Clay

The process of adsorption of metal ions by immobilized marine algae with the existence of clay was investigated. It can be noted from the results that, after mixing with clay, the adsorption rate increases rapidly with the increasing amount of the marine algae. When pH=5, the best ratio between the clay and the marine algae is 1：4 for Pb^2＋. The result of in situ handling of the waste water containing heavy metals shows that the average adsorption rates of heavy metal irons Cu^2＋, Cd^2＋, Pb^2＋ and Ni^2＋ are all over 70 %.     

四种金属离子对中国对虾无节幼体生长的毒性影响

对虾工厂化育苗在我国沿海已经普及,对虾人工养殖也在沿海地区蓬勃发展,到1992年养殖面积已达200多万亩,人工育苗场全国约有上千个。养殖对虾已成为我国水产业中规模最大、经济效益最高的水产品。但近几年来沿海地区的工业飞速发展,沿岸海水均受到了不同程度的污染,各对虾育苗场卵孵化率普遍下降。今年我国养殖对虾又出现了大面积暴发性死亡,原因是复杂的,但作者认为,治虾病之本应是治水质。众所周知,一切生物的幼体阶段都是最敏感的时期,海水中的金属离子对对虾幼体生长的影响已有报道(吴彰宽等,1988; Lawrence et al.,1981),但其实验环境、方法及条件各有不同。作者于1992年5月至1993年4月在海阳育苗场作了现场实验,本文根据实验结果分析和研究了Zn、Cd、Pb、Cu金属离子对中国对虾受精卵及无节幼体生物毒性的影响;不同pH值海水加入不同浓度的混合金属离子,对无节幼体生长的毒性影响;不同盐度的海水加入不同浓度的混合金属离子对无节幼体生长毒性的影响。     

胶州湾沉积物重金属形态不同浸取方法的比较与污染讯息指示作用初探

海洋沉积物中重金属的活性形态对于指示沉积物污染状况具有重要作用;为探寻简洁且能够有效提取重金属活性形态的浸提方法;实验研究了0.1 mol/L和1 mol/L盐酸的单级提取和欧共体标准局（European Community Bureau of Reference）提出的BCR分级提取法对胶州湾表层沉积物中重金属（Cr、Cu、Ni、Pb、Zn）和Al、Fe、Mn的浸取效果。结果显示;3种提取方法提取的金属含量呈显著正相关关系;两种浓度的稀盐酸对BCR方法中的酸可提取态和可还原态金属均具有较好浸提效果;但对可氧化态金属浸提能力相对较弱。不同提取方法的人为信号指数（ASI）计算结果表明;BCR浸取法提取结果的金属ASI值最大;表明其对沉积物中金属活性形态提取效率较高;1 mol/L HCl提取结果的金属ASI值最低;可能是较高浓度强酸使沉积物较大颗粒内层中“惰性”金属被浸取出来;“增加”了金属活性组分的污染讯息信号;对沉积物中Cu、Pb和Zn而言;0.1 mol/L HCl提取结果的ASI值与BCR方法接近。经过Al归一化后;0.1 mol/L HCl浸提的重金属含量的空间分布与胶州湾的实际污染状况相吻合;表明0.1 mol/L的HCl在一定程度上能够代替复杂的BCR浸取法;此方法可简化重金属活性形态的提取步骤;适合大范围沉积物重金属污染评价。     

基于Landsat-8 OLI影像的南沙群岛岛礁遥感调查研究

海洋沉积物中重金属的活性形态对于指示沉积物污染状况具有重要作用;为探寻简洁且能够有效提取重金属活性形态的浸提方法;实验研究了0.1 mol/L和1 mol/L盐酸的单级提取和欧共体标准局（European Community Bureau of Reference）提出的BCR分级提取法对胶州湾表层沉积物中重金属（Cr、Cu、Ni、Pb、Zn）和Al、Fe、Mn的浸取效果。结果显示;3种提取方法提取的金属含量呈显著正相关关系;两种浓度的稀盐酸对BCR方法中的酸可提取态和可还原态金属均具有较好浸提效果;但对可氧化态金属浸提能力相对较弱。不同提取方法的人为信号指数（ASI）计算结果表明;BCR浸取法提取结果的金属ASI值最大;表明其对沉积物中金属活性形态提取效率较高;1 mol/L HCl提取结果的金属ASI值最低;可能是较高浓度强酸使沉积物较大颗粒内层中“惰性”金属被浸取出来;“增加”了金属活性组分的污染讯息信号;对沉积物中Cu、Pb和Zn而言;0.1 mol/L HCl提取结果的ASI值与BCR方法接近。经过Al归一化后;0.1 mol/L HCl浸提的重金属含量的空间分布与胶州湾的实际污染状况相吻合;表明0.1 mol/L的HCl在一定程度上能够代替复杂的BCR浸取法;此方法可简化重金属活性形态的提取步骤;适合大范围沉积物重金属污染评价。     

The adsorption and interaction of long-chain fatty acids and heavy metals at the mercury electrode/sodium chloride solution interface

The reduction of heavy metals (cadmium, lead and zinc) in the presence of long-chain fatty acids (lauric, oleic and linoleic) in 0.55 mol dm^?3 NaCl and 0.03 mol dm^?3 NaHCO₃ at pH 8.7 has been studied by differential pulse polarography. The increase of the peak height of investigated metals by up to tenfold the value obtained in electrolyte without fatty acid is due to adsorption of metal ions at the electrode surface. The accumulation of metal increases with the increase of adsorption time (at potentials more positive than the reduction potential of the particular metal) and with increase of salinity. The heavy-metal adsorption depends on the concentrations of both metal ions and fatty acids. The interaction of heavy metals with the unsaturated fatty acids in the bulk and/or in the adsorbed layer at different natural interfaces could be of considerable importance in an understanding of the fate and distribution of heavy metals in the natural aquatic environment.     

混合暴露条件下刺参(Apostichopus japonicus)对重金属的富集与释放特征

应用双箱动力学模型模拟了刺参在Pb、Zn、Cu、Cd、Cr、Hg和As 7种重金属混合暴露条件下,呼吸树、消化道和体壁组织对重金属的生物富集与释放实验。结果表明:(1)重金属在刺参组织器官中的富集具有选择性,理论平衡状态下,As、Cd、Cr在各组织的含量分布(CAmax):呼吸树消化道体壁,Cu、Zn分布规律(CAmax):消化道呼吸树体壁,Hg、Pb分布规律(CAmax):体壁呼吸树消化道。(2)刺参对不同重金属的富集系数存在显著差异(P0.05),呼吸树组织对Cr离子富集系数最高2298.2,其次是Cu、Cd离子,其BCF均在1500以上,Hg、Pb、Zn和As离子在呼吸树中的富集系数较低。体壁对Cu离子的富集系数最高为1560.7,对As离子富集系数最低52.7。消化道对Cu离子富集系数最高6037,对As离子富集系数最低为87.9。     

Studies in seawater and lake water on interactions of trace metals with humic substances isolated from marine and estuarine sediments: II. Voltammetric investigations on trace metal complex formation in the dissolved phase

In seawater and lake water the complexation of several heavy metals, present in the dissolved state at relevant trace levels, with humic substances isolated from two marine and an estuarine sediment has been studied by differential pulse anodic stripping voltammetry (DPASV) at a hanging mercury drop electrode (HMDE). Taking Zn(II) as an example, the aim of this study was to gain direct information on the general level of importance of humic substances for the speciation of certain heavy metals in fresh and saline waters.In seawater humic acids originating from different sediments have very similar complexing properties for Zn(II), decreasing slightly in the order HAN > HAL > HAM. In lake water HAL is most efficient for complexing Zn(II), followed by HAN and HAM.In both types of natural waters, the sedimentary fulvic acid is less efficient in complexing Zn(II) than the respective humic acid from the same site. In general, the complexing efficiency decreases in the order EDTA > NTA > humic acids > fulvic acid.The problem of humic acid adsorption at the electrode, which somewhat limits the investigation of Pb(II) and Cd(II), and the impact of pH on the amount of complexed Zn(II) are also discussed.The findings provide further direct evidence for the conclusion previously drawn from existing complexation data that because of the rather low levels of dissolved humics in large parts of the oceans, the complexation efficiency of humics for Cd, Pb and Zn is too low to affect the speciation pattern of these three heavy metals.     

菲和Cd2+单一及复合污染对毛蚶氧化胁迫效应的比较

采用半静态染毒实验研究了菲和Cd²⁺单一及复合污染下胁迫9 d和清水释放2 d过程中毛蚶体内活性氧(ROS)、谷胱甘肽(GSH)含量和谷胱甘肽硫转移酶(GST)活性的变化。结果表明,菲和Cd²⁺单独胁迫能诱导毛蚶体内ROS含量的增加及GSH含量、GST活性的降低,且随染毒浓度的增加,对各指标影响愈明显,存在剂量-效应关系。毛蚶体内GSH和GST的变化趋势具有一致性。菲和Cd²⁺复合污染对毛蚶体内的氧化胁迫效应整体大于二者单独污染。在清水释放阶段,单一及复合污染胁迫组各指标均能恢复至对照组水平。表明毛蚶体内抗氧化系统适合作为监测海洋多环芳烃和重金属复合污染的生物标志物。