摘要
为了识别内陆封闭型湖泊表层沉积物中重金属元素Pb、Zn、Cu、Cd、Cr的赋存形态特征与生物有效性,我们选取柴达木盆地尕海作为研究对象,采集并精选了20件表层沉积物样品。研究基于Tessier连续提取法结合ICP-MS测定了上述5种重金属元素的赋存形态,并利用风险评价编码法和次生相与原生相分布比值法对研究区内重金属元素的生物有效性进行了评价。研究结果表明,Pb、Zn、Cu、Cd和Cr元素的平均含量值分别为35.30 mg/kg、146.15 mg/kg、44.68 mg/kg、0.35 mg/kg和103.47 mg/kg,富集系数分别为1.69、1.82、2.01、2.50和1.48,并且在空间上呈现不均匀分布特征。Pb、Zn、Cu和Cr元素主要以残渣态为优势形态,分别占其总量的51.54%、80.98%、73.00%和92.02%;Cd主要以铁锰氧化物结合态为优势形态,占其总量的58.99%。Pb、Zn、Cu、Cd和Cr元素的劣势形态为碳酸盐结合态和离子交换态,分别占其总量的0.05%和0.09%、0.26%和0.53%、0.34%和1.68%、0.50%和3.55%、0.05%和0.09%。RAC风险评价结果为Cu>Cd>Zn>Pb=Cr,而RSP风险评价结果则是Cd>Pb>Cu>Zn=Cr。Pb、Zn、Cu以及Cr元素的生物有效性相对较低,而Cd元素的生物有效性则相对较高。虽然活性组分占比较小,但其潜在的生态风险较高,尤其Cd元素,应引起足够的重视。
In order to identify the occurrence form characteristics and bioavailability of Pb,Zn,Cu,Cd and Cr from surface sediments in inland enclosed lakes,we collected and selected 20 surface sediment samples from Lake Gahai in Qaidam Basin as the study object.Based on the Tessier continuous extraction as well as ICP-MS methods,the occurrence forms of Pb,Zn,Cu,Cd and Cr were determined,and the bioavailability of heavy metals mentioned-above was evaluated by RAC and RSP methods.The results showed that the average content of Pb,Zn,Cu,Cd and Cr were 35.30 mg/kg,146.15 mg/kg,44.68 mg/kg,0.35 mg/kg and 103.47 mg/kg,respectively.The enrichment coefficients were 1.69,1.82,2.01,2.50 and 1.48,respectively,showing an uneven spatial distribution characteristics.Elements Pb,Zn,Cu and Cr were predominantly presented in the residual fraction,accounting for 51.54%,80.98%,73.00%and 92.02%of the total amounts,respectively.Cd was predominantly presented in the Fe-Mn oxide fraction,accounting for 58.99%of its total amount.The disadvantaged forms of Pb,Zn,Cu,Cd and Cr were car‐bonate and ion exchanged fractions,accounting for 0.05%and 0.09%,0.26%and 0.53%,0.34%and 1.68%,0.50%and 3.55%,0.05%and 0.09%of the total amounts,respectively.The RAC risk assessment results suggested Cu>Cd>Zn>Pb=Cr,while the RSP risk assessment results indicated Cd>Pb>Cu>Zn=Cr.The bioavailability of Pb,Zn,Cu and Cr was relatively low,while the bioavailability of Cd was relatively high.Although the proportion of active components was relatively small,the potential ecological risks were high,especially Cd.
作者
高春亮
文进心
成艾颖
李鸿宇
魏海成
闵秀云
安海西
GAO Chunliang;WEN Jinxin;CHENG Aiying;LI Hongyu;WEI Haicheng;MIN Xiuyun;AN Haixi(Key Laboratory of Green and High-end Utilization of Salt Lake Resources,Qinghai Institute of Salt Lakes,Chinese Academy of Sciences,Xining,810008,China;Qinghai Provincial Key Laboratory of Geology and Environment of Salt Lake,Xining,810008,China;University of Chinese Academy of Sciences,Beijing,100049,China;Forestry and Grassland Bureau of Haixi Mongolian and Tibetan Autonomous Prefecture,Delingha,817099,China)
出处
《盐湖研究》
2025年第6期81-89,共9页
Journal of Salt Lake Research
基金
青海省应用基础研究项目(2022-ZJ-732)
青海省“昆仑英才˙高端创新创业人才”计划项目(高春亮)
第二次青藏高原综合科学考察研究项目(2019QZKK0805)。
关键词
表层沉积物
重金属元素
赋存形态
生物有效性
尕海
柴达木盆地
Surface sediments
Heavy metal elements
Occurrence form
Bioavailability
Lake Gahai
Qaidam Basin
