Enrique Muñoz-Arcos, Geoffrey E. Millward, Caroline C. Clason, Richard Hartley, Claudio Bravo-Linares, William H. Blake
{"title":"Variability of fallout radionuclides (FRNs) in river channels: implications for sediment tracing","authors":"Enrique Muñoz-Arcos, Geoffrey E. Millward, Caroline C. Clason, Richard Hartley, Claudio Bravo-Linares, William H. Blake","doi":"10.1007/s11368-024-03881-z","DOIUrl":null,"url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Purpose</h3><p>The aims of this research were to assess the sources of variability of particulate FRNs (<sup>7</sup>Be, <sup>210</sup>Pb<sub>ex</sub> and <sup>137</sup>Cs) in river channels, the influence of sediment properties such as particle size distribution (PSD) and organic matter (OM) on FRN distributions, and to discuss the implications for sediment tracing in rivers.</p><h3 data-test=\"abstract-sub-heading\">Methods</h3><p>Suspended and channel bed sediment samples were collected in the River Avon (Devon, UK) during five strategic surveys involving a wide variation of river flows, including flood conditions. Particulate matter was analysed for <sup>7</sup>Be, <sup>210</sup>Pb<sub>ex</sub> and <sup>137</sup>Cs by gamma spectrometry, PSD by laser diffraction, and organic constituents, total organic carbon (TOC) and total nitrogen (TN) by elemental analysis.</p><h3 data-test=\"abstract-sub-heading\">Results</h3><p>FRNs activity concentrations vary significantly both spatially, characterised by changes in activity concentrations within and between locations, and temporally, with changes during the storm hydrograph and between seasons. Variability was attributed to changes in sediment sources and, on some occasions, to significant correlation of activity concentrations with sediment properties. The results also highlighted the influence of changes in channel characteristics and the magnitude and frequency of floods on FRN distributions.</p><h3 data-test=\"abstract-sub-heading\">Conclusion</h3><p>In the context of sediment tracing, attention should be given to seasonal changes in riverine conditions that have the potential to affect <sup>7</sup>Be and <sup>137</sup>Cs conservativeness. Application of FRNs in sediment fingerprinting studies should be accompanied by appropriate temporal characterisation of potential sediment sources. Finally, potential contribution of <sup>7</sup>Be-depleted sediment from channel resuspension to the suspended load should also be considered.</p>","PeriodicalId":17139,"journal":{"name":"Journal of Soils and Sediments","volume":null,"pages":null},"PeriodicalIF":2.8000,"publicationDate":"2024-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Soils and Sediments","FirstCategoryId":"97","ListUrlMain":"https://doi.org/10.1007/s11368-024-03881-z","RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"ENVIRONMENTAL SCIENCES","Score":null,"Total":0}
引用次数: 0
Abstract
Purpose
The aims of this research were to assess the sources of variability of particulate FRNs (7Be, 210Pbex and 137Cs) in river channels, the influence of sediment properties such as particle size distribution (PSD) and organic matter (OM) on FRN distributions, and to discuss the implications for sediment tracing in rivers.
Methods
Suspended and channel bed sediment samples were collected in the River Avon (Devon, UK) during five strategic surveys involving a wide variation of river flows, including flood conditions. Particulate matter was analysed for 7Be, 210Pbex and 137Cs by gamma spectrometry, PSD by laser diffraction, and organic constituents, total organic carbon (TOC) and total nitrogen (TN) by elemental analysis.
Results
FRNs activity concentrations vary significantly both spatially, characterised by changes in activity concentrations within and between locations, and temporally, with changes during the storm hydrograph and between seasons. Variability was attributed to changes in sediment sources and, on some occasions, to significant correlation of activity concentrations with sediment properties. The results also highlighted the influence of changes in channel characteristics and the magnitude and frequency of floods on FRN distributions.
Conclusion
In the context of sediment tracing, attention should be given to seasonal changes in riverine conditions that have the potential to affect 7Be and 137Cs conservativeness. Application of FRNs in sediment fingerprinting studies should be accompanied by appropriate temporal characterisation of potential sediment sources. Finally, potential contribution of 7Be-depleted sediment from channel resuspension to the suspended load should also be considered.
期刊介绍:
The Journal of Soils and Sediments (JSS) is devoted to soils and sediments; it deals with contaminated, intact and disturbed soils and sediments. JSS explores both the common aspects and the differences between these two environmental compartments. Inter-linkages at the catchment scale and with the Earth’s system (inter-compartment) are an important topic in JSS. The range of research coverage includes the effects of disturbances and contamination; research, strategies and technologies for prediction, prevention, and protection; identification and characterization; treatment, remediation and reuse; risk assessment and management; creation and implementation of quality standards; international regulation and legislation.