生物扰动对沉积物中污染物环境行为与生物可利用性的影响

Influence of Bioturbation on Fate and Bioavailability of Sediment-Associated Contaminants

疏水性有机污染物进入环境水体后易于与沉积物结合,对沉积物中的底栖动物造成危害。底栖动物引起的生物扰动作用可以通过改变沉积物的地球化学性质,对其中污染物的赋存形态、迁移转化和生物可利用性产生重要影响。在综述了国内外生物扰动影响沉积物中污染物环境行为和生物可利用性的最新研究进展基础上,重点讨论了沉积物颗粒交换、水体环境条件改变、疏水有机污染物解吸释放过程以及对生物扰动影响的定量化表征。最后对该研究方向进行了展望,指出应重点研究多种污染物及不同生物共存条件下的生态效应,以及造成沉积物扰动的影响因素的定量化表征等。

Hydrophobic organic contan-ants and heavy metals tend to bind to the solid phases including bed sedi- ments and suspended particles, in aquatic ecosystems. Sediment-associated contanfinants may be released to water body under certain conditions. Bioturbation caused by the activities of benthic organisms is one of the factors affecting fate of chemicals in sediment. By altering sediment geochemistry characteristics, the bioturbation influenced on distnou- tion, transport, bioavailability and toxicity of contarrfinants in sedin^nt. This paper reviewed the recent studies on how bioturbation affects environmental fate and risks of sediment-associated contan^ants, with a focus on movements of sediment particles, alteration of characteristics of water body, desorption of contan^nants from sediment, and quantita- tive characterization of bioturbation. In the future, more studies will be required to better understand the effects ofbio- turbation on multiple classes of contan-finants, the influence of bioturbation on bioavailability and toxicity of contarni-nants to the co-exposed organisms, as well as the quantitative characterization of bioturbation.