The distribution and transport of the natural fallout radionuclide 210Pb in the atmosphere and through catchment/lake systems
The distribution and transport of the natural fallout radionuclide 210Pb in the atmosphere and through catchment/lake systems
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自然沉降放射性核素 210Pb 在大气中以及通过流域/湖泊系统的分布和传输
DOI：
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发表时间：
2018
期刊：
影响因子：
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通讯作者：
P. Semertzidou
中科院分区：
文献类型：
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作者：
P. Semertzidou
从最近的137 Cs和210铅在Brotherswater，坎布里亚郡，多芯研究的结果进行了比较，从两个类似的多芯研究在同一个湖在1976/7和1988/9。这项新研究的目的是评估Brotherswater沉积物中这些放射性核素沉降记录的长期稳定性及其作为沉积物定年工具的可靠性。六个岩心取自湖的四个不同区域，与早期研究中使用的岩心相似。按照与1988/9年研究中使用的类似方案，对每个岩心的干燥沉积物样品进行了210 Pb、226 Ra、137 Cs和241 Am的伽马能谱分析。137 Cs的结果以图形方式说明了记录1963年大气层核武器试验沉降物最大值的浓度峰值的逐渐掩埋，以及随后由于放射性衰变而减少。1986年后的核心的特点是从1986年切尔诺贝利事故的第二个峰值记录沉降物的外观和埋葬。在1986年之后的岩芯中，1963年的137 Cs峰值的鉴定被241 Am的痕迹所证实，241 Am也是核武器试验的产物。在1988/1989年的研究和本研究中，使用CRS模型计算的210 Pb年龄大部分将1963年和1986年的深度与137 Cs记录确定的深度非常相似。这一协议在二十多年的时间里得到维持，证明了该湖沉积物记录的可靠性以及用于解释这些记录的模型的有效性。137 Cs的记录太模糊，1963年又太近，无法与1976/7年的岩心进行类似的比较。210铅和137铯日期之间的协议是最好的网站，210铅的沉积物记录的净供应率是可比的大气通量。小，但显着的差异，观察到的210铅供应率大大超过大气通量的网站，最有可能是由于额外的时间依赖性输入的集水区，或沉积后沉积物内的湖泊重新分配。帕纳焦塔·塞梅尔齐杜
Results from a recent multi-core study of 137Cs and 210Pb in Brotherswater, Cumbria, are compared with those from two similar multi-core studies carried out at the same lake in 1976/7 and 1988/9. The purpose of this new study was to assess of the longterm stability of fallout records of these radionuclides in the sediments of Brotherswater and their reliability as tools for dating the sediments. Six cores were taken from four different areas of the lake, similar to those used in the earlier studies. Dried sediment samples from each core were analysed by gamma spectrometry for 210Pb, 226Ra, 137Cs and 241Am following a similar protocol to that used in the 1988/9 study. The 137Cs results graphically illustrate the progressive burial of a peak in concentrations recording the 1963 fallout maximum from the atmospheric testing of nuclear weapons, and its subsequent reduction due to radioactive decay. The post1986 cores are characterised by the appearance and burial of a second peak recording fallout from the 1986 Chernobyl accident. Identification of the 1963 137Cs peak in post-1986 cores was confirmed by the co-presence of traces of 241Am, also a product of nuclear weapons test fallout. In both the 1988/9 study and the present study, 210Pb dates calculated using the CRS model for the most part placed 1963 and 1986 at depths very similar to those determined from the 137Cs records. The maintenance of this agreement over a period of more than two decades provides evidence of the reliability of sediment records in this lake and the validity of models used to interpret them. The 137Cs records were too indistinct and 1963 too recent to make similar comparisons in the case of the 1976/7 cores. Agreement between 210Pb and 137Cs dates was best at sites where the net rate of supply of 210Pb to the sediment record was comparable to the atmospheric flux. Small but significant discrepancies were observed at sites where the 210Pb supply rate greatly exceeded the atmospheric flux, most probably due to additional time-dependent inputs from the catchment, or post-depositional sediment redistribution within the lake. Panagiota Semertzidou
影响因子：
5.8
作者：
D. Schillereff;R. Chiverrell;N. Macdonald;J. Hooke
通讯作者：
D. Schillereff;R. Chiverrell;N. Macdonald;J. Hooke
量化英格兰西北部兄弟沃特历史采矿金属污染的系统扰动和恢复
影响因子：
2.1
作者：
Schillereff D
通讯作者：
Schillereff D