钦州湾东部海域表层水和浮游生物中六种重金属含量和污染评价研究

摘要

With field observation data of heavy metal pollution in surface water and plankton in the eastern area of Qinzhou Bay in December 2014,combined with pollution degree evaluation and seawater quality standard,the content and pollution evaluation of six heavy metals were assessed in these areas by adopting single factor index (SFI),enrichment factor analysis.The results showed that the contents of heavy metals on the surface ocean water of the eastern area in the Qinzhou Bay were Cd＞Cr＞Zn＞As＞Cu＞Hg,the content of Zn,As,Cu,Hg has reached national class Ⅰ seawater standards for water quality and the content of Cr meet the national class Ⅱ seawater standards while the content of Cd in Zn and Cd exceed the standard;the heavy metal Cr,Hg,As and Cu contents were 6.57×101mg/kg dry weight,1.51×l0-1mg/kg dry weight,4.13 × 10-1mg/kg dry weight,9.48 × 10-3mg/kg dry weight,1.85 × 10-1mg/kg mg/kg dry weight,6.89 × 100mg/kg dry weight respectively in plankton.The heavy metal contents in plankton are much higher than that of surface ocean water.Plankton concentration coefficient of heavy metals is up to 40000,indicating that plankton has a strong ability to concentrate heavy metals.%本文采用单因子污染指数法(SFI)和生物富集系数(BCF)分析并结合污染程度评价和海水水质标准,研究和评价了2015年12月钦州湾东部海域表层水和浮游生物中Zn、Cd、Cr、Hg、As、Cu六种重金属的含量和污染现状.结果表明,钦州湾东部海域表层水中重金属含量大小依次为Cd＞Cr＞Zn＞As＞Cu＞Hg,其中Zn、As、Cu、Hg含量符合国家一类海水水质标准,Cr含量符合国家二类海水水质标准,Cd含量超标;浮游生物中Zn、Cd、Cr、Hg、As、Cu含量依次为6.57× 101mg/kg干重、1.51×10-1mg/kg干重、4.13× 10-1mg/kg干重、9.48×10-3mg/kg于重、1.85×10-1mg/kg干重、6.89×100mg/kg干重,浮游生物中重金属含量远高于表层水中的重金属含量.浮游生物对重金属的富集系数最高达40000,表明浮游生物对重金属有很强的富集能力.