摘要
在三峡库区4个典型区域消落带分时段采集了3种不同类型的沉积物样品36个,对沉积物样品中汞的赋存形态及生物可利用性进行了研究.结果表明,三峡库区消落带汞的污染程度较轻,沉积物中汞甲基化的速率和程度处于较低的水平.7月份和9月份采集的库区消落带沉积物甲基汞(MeHg)的含量分别为0.128±0.028ng/g和0.031±0.027ng/g.7月份MeHg∶THg的值为0.296±0.154%,9月份MeHg∶THg的值为0.069±0.081%,两者相差近3倍.不同类型沉积物MeHg∶THg的值也存在差异,大小顺序总体表现为淹水沉积物,半淹水沉积物和落干沉积物.7月份库区消落带沉积物中汞的赋存形态依次为强络合态(46.99%)、硫化物结合态(36.28%)、有机及其他络合态(9.57%)、水溶态(4.49%)、胃酸溶态(2.67%).强络合态是7月份库区消落带沉积物中汞主要的赋存形态.9月份库区消落带沉积物中汞的赋存形态依次为硫化物结合态(46.47%)、强络合态(34.73%)、有机及其他络合态(14.18%)、胃酸溶态(2.40%)、水溶态(2.21%).硫化物结合态是9月份库区消落带沉积物中汞主要的赋存形态.
Thirty-six sediment samples in 4 typical sites along the riparian zone of Three Gorges Reservoir Area, China, were analyzed to investigate the speciation and bioavailability of mercury （Hg） in them. The result showed that there was just slightly contaminated by mercury, and lower methylation potential was found in sediment of WLFZ. The concentrations of methyl mercury （MeHg） in the sediment of the riparian zone in July and September were 0. 128±0. 028 ng/g and 0. 031±0. 027 ng/g, respectively. The MeHg： THg ratio in the sediment in July and September was 0. 296±0. 154% and 0. 069±0. 081%, respectively, a triple difference. The MeHg：THg ratio differed with different types of sediment as well, being greater in flooding sediment than in semi-flooding sediment and the value of drying sediment being the least. The content of different Hg fractions of the sediments collected in July was the highest in Hg-e （46.99%）, followed in order by Hg s （36.28%）, Hg-o （9.57%）, Hg-w （4.49%） and Hg-h （2. 67%）. The content of different Hg fractions of the sediments collected in September was the highest in Hg-s （46.47%）, fol- lowed in order by Hg-e （34.73%）, Hg-o （14.18%）, Hg-h （2. 40%） and Hg-w （2.21%）. In other words, Hg-s was the main fraction of sediments in September.
出处
《西南大学学报（自然科学版）》
CAS
CSCD
北大核心
2013年第11期14-20,共7页
Journal of Southwest University(Natural Science Edition)
基金
"973"计划(2013CB430004)
国家自然科学基金面上项目(41373113
41173116)
关键词
消落带
沉积物
赋存形态
生物可利用性
三峡库区
riparian zone
sediment
speeiation
bioavailability
Three Gorges Reservoir Area
