摘要
河口区既是人类排污物的主要汇集地，又是单向流体和双向流体相互作用的场所，三者构成一个复杂而多变的地球化学物理场。在这里因一定的物理、化学和生物化学作用使来自陆地的重金属污染物从水体中沉降下来，进入底部沉积物即积累过程，又会因类似的作用使这些金属从沉积物中活化而再次进入水体即释放过程，产生所谓的“二次污染”，河口沉积物水界面过程调控着这一体系的方向与限度。对该领域在过去几年里的主要研究成果进行阐述，进而指明该领域研究中有待解决的问题。
Various factors governing the accumulation, dispersion and form exchanges of heavy metals at sediment water interface of estuaries are discussed and reviewed. Concentrations and bioavailabilities of heavy metals in estuaries depended on many different processes, including:①mobilization of metals of the porewater and their chemical properties;②transportation of metals at sediment water interface;③sediment components;④organism activities, and⑤effect of water current washing and disturbance, bioturbulence, salinity, redox and pH on the processes. So far some conclusions have been achieved:①concentration and distribution of heavy metals in major estuaries and adjacent areas were measured;②sequential extraction procedure for the specification for heavy metals have been presented and widely applied to study on metal behaviors in water environment;③research on relationship between organism growth and content of heavy metal in organism was made by in situ measures and indoor toxic culture experiments;④lots of experiments for sorption and desorption of heavy metals on various material have been completed and presented many isotherm equations;⑤several methods for determining background values of metals have been set up. Some problems to be resolved in near future are those:①quantitative study on biogeochemical cycling model of heavy metals;②metal release from sediments would become another source of pollution and must be pay attention to;③international standard analysis for heavy metals, especially for specification determinations, should be set up.
出处
《地球科学进展》
CAS
CSCD
1997年第5期434-439,共6页
Advances in Earth Science
关键词
沉积物
水界面过程
重金属
生物地球化学
Biogeochemical processes, Heavy metals, Sediment water interface, Estuary
