摘要
采用ICP-MS研究湘江衡阳段上覆水、悬浮颗粒物、表层沉积物及孔隙水中重金属的含量及分布特征.结果表明,湘江衡阳段主要的重金属污染元素是Cd,上覆水中Cd的平均含量为0.26μg·L-1,高于美国水质基准的持续基准浓度CCC(USEPA2009),已经对部分水生生物表现出潜在的毒性效应;悬浮颗粒物和表层沉积物中Cd的富集含量较高,分别为42.03μg·g-1和29.62μg·g-1,达到加拿大淡水沉积物保护准则最初影响水平TEL的70倍和50倍,其中,从沉积物中取得的孔隙水中Cd平均含量为3.8μg·L-1,该值是CCC的15倍甚至高于最大基准浓度(CMC),已经对部分水生生物表现出实际的急性毒性效应.湘江衡阳段重金属的空间分布特征表现为中下游污染较上游严重,在衡阳水口山地区等污染企业密集区,重金属含量较高,表明人类活动输入已经成为湘江重金属的重要来源.研究结果还表明,悬浮颗粒物及沉积物相作为水体重金属污染物的主要赋存介质,对重金属污染的迁移、沉积、转化及生物富集作用具有决定性的意义,其重要性不容忽视.
The contents and distribution features of heavy metals in the surface water, suspended solids, surface sediments and pore water in Hengyang section of Xiangjiang River were studied by 1CP-MS. The results showed Cd was the most polluted heavy metals in Hengyang section of Xiangjiang River. The concentration of Cd in surface water was 0.26 μg·L^-1 , which exceeded its Criteria Continuous Concentration ( US Water Quality Criteria, EPA 2009 ) and might have potential toxic effect on several aquatic organisms. The average concentrations of Cd in suspended solids and surface sediments were 42.03 μg·g^-1 and 29.62 μg·g^-1 respectively, which were 70 times and 50 times the Threshold Effect Level ( Canada Sediment Quality Guideline). The average concentration of Cd in pore water was 3.8 μg·L^-1 , which was 15 times the CCC and even higher than Criteria Maximum Concentration (CMC) and might have acute toxic effect on several aquatic organisms. Heavy metal in the middle and lower reaches of Xiangjiang River in Hengyang section had a notably higher concentration than the upper reaches, especially in Shui Koushan section where many pollution - discharging enterprises were distributed. This showed that anthropogenic input had become an important source of heavy metals in Xiangjiang River. Results of this study also showed that suspended solids and sediments played a key role in the transport, sedimentation, transformation and bioaccumulation in aquatic environment as the main accumulated media.
出处
《环境科学学报》
CAS
CSCD
北大核心
2012年第11期2836-2844,共9页
Acta Scientiae Circumstantiae
基金
国家水体污染与控制重大专项(No.2009ZX07528-002
2012ZX07503-002)~~
关键词
表层沉积物
悬浮颗粒物
孔隙水
上覆水
重金属污染
湘江衡阳段
surface sediment
suspended solids
pore water
surface water
pollution of heavy metal
Hengyang section of Xiangjiang River