研究报告
史佳莹,孙柳,李立青,张洪,唐文忠.黑臭水体治理Ⅱ：沉积物耗氧方式对重金属形态及生物有效性的影响[J].环境科学学报,2023,43(2):11-21
黑臭水体治理Ⅱ：沉积物耗氧方式对重金属形态及生物有效性的影响
- Treatment of black and odorous water Ⅱ： Effects of oxygen consumption of sediment on speciation and bioavailability of heavy metals
- 基金项目：国家自然科学基金（No.41877368）
- 作者
- 单位
- 史佳莹
- 中国科学院生态环境研究中心环境水质学国家重点实验室，北京 100085;中国地质大学（武汉）环境学院，武汉 430074
- 孙柳
- 中国科学院生态环境研究中心环境水质学国家重点实验室，北京 100085;黄河水利水电开发集体有限公司，郑州 450000;中国科学院大学，北京 100049
- 李立青
- 中国地质大学（武汉）环境学院，武汉 430074
- 张洪
- 中国科学院生态环境研究中心环境水质学国家重点实验室，北京 100085;中国科学院大学，北京 100049
- 唐文忠
- 中国科学院生态环境研究中心环境水质学国家重点实验室，北京 100085;中国科学院大学，北京 100049
- 摘要：缺氧导致水体黑臭已成为我国许多河流普遍存在的污染问题，而沉积物耗氧是水体溶解氧减少的重要过程.本文通过构建一套室内模拟装置，利用薄膜扩散梯度（DGT）技术和改进的BCR三步连续提取法来探索黑臭水体沉积物不同耗氧方式对水体氧化还原体系和沉积物中 重金属（Co、Ni、Cu、As、Sb和Pb）形态及生物有效性的影响.结果表明，厌氧培养过程中上覆水氧化还原电位为-65.50~0 mV，属于铁锰控制区；沉积物氧化还原电位为-170.30~-370.10 mV，主要由硫体系控制.化学耗氧，主要是其中的铁锰耗氧，会使沉积物中生物有效态Fe、Mn、S浓度增加，进而影响重金属的迁移转化.化学耗氧组上覆水中As浓度增加至9.64 μg·L-1，铁锰耗氧组上覆水中Co、Ni和As浓度分别增加至20.79、20.53和6.97 μg·L-1.化学耗氧组表层沉积物中生物有效态Co、Ni和As浓度增加至7.03、6.18和6.98 μg·L-1，而铁锰耗氧组其浓度增加至8.62、11.80和2.44 μg·L-1.说明不同耗氧方式会对沉积物氧化还原体系产生影响，并通过改变铁锰硫体系影响沉积物种重金属的形态和生物 有效性.
- Abstract：Black odorous caused by anoxic in water bodies has become a common pollution problem in many rivers in China. The oxygen consumption of deposition is an important process of the reduction of dissolved oxygen in the water. In this paper， a laboratory-scale training simulator was developed using the diffusive gradients in thin-films （DGT） technology and modified BCR method to assess the effects of the black odorous water body oxygen consumption ways to the redox system of overlying water and the speciation and biological effectiveness of heavy metals （Co， Ni， Cu， As， Sb and Pb） in the sediment. The results showed that the redox potential of overlying water ranged from -65.50 mV to 0 mV， belonging to the Fe-Mn controlled zone， while the redox potential of sediment ranged from -170.30 mV to -370.10 mV， mainly controlled by the S. Chemicals oxygen consumption， mostly contributed from the consumption of Fe and Mn， could lead to increases of the concentrations of bioavailable Fe， Mn and S in the sediments， and further affect the migration and transformation of heavy metals. In the group of chemical oxygen consumption， the concentration of As in overlying water increased to 9.64 μg·L-1， while the concentrations of Co， Ni and As in overlying water increased to 20.79， 20.53 and 6.97 μg·L-1， respectively， in the group of Fe and Mn oxygen consumption. The concentrations of bioavailable Co， Ni and As in the sediment increased to 7.03， 6.18 and 6.98 μg·L-1， respectively， in the group of chemical oxygen consumption， while the concentrations of bioavailable Co， Ni and As increased to 8.62， 11.80 and 2.44 μg·L-1， respectively， in the group of Fe and Mn oxygen consumption. These results indicated that different oxygen consumption ways could affect the redox system of sediment， as well as the speciation and bioavailability of heavy metals in sediment by changing Fe， Mn and S in the water.
摘要点击次数： 138 全文下载次数： 201
