Choi Hye-Bin, Lee Kwang-Sik, Park Sanghee, Jeong Eui-Kuk, Gautam Mukesh Kumar, Shin Woo-Jin
Research Center for Geochronology and Isotope Analysis, Korea Basic Science Institute, Cheongju-si, Chungbuk 28119, Republic of Korea; Department of Science Education, Ewha Womans University, Seoul, 03760, Republic of Korea; Healthcare & Spa industry Promotion Agency, Chungnam, 31471, Republic of Korea.
Research Center for Geochronology and Isotope Analysis, Korea Basic Science Institute, Cheongju-si, Chungbuk 28119, Republic of Korea; Graduate School of Analytical Science and Technology, Chungnam National University, Daejeon, 34134, Republic of Korea.
Chemosphere. 2023 Mar;317:137895. doi: 10.1016/j.chemosphere.2023.137895. Epub 2023 Jan 16.
Successful application and accurate interpretation of strontium (Sr) isotope ratios (Sr/Sr) requires underlying information about the large-scale variabilities in their signatures from a variety of environmental samples, which can be correlated with the Sr isotopic signatures of underlying local geology. In this national-scale study, we analyzed Sr/Sr in soil, plants, stream water, and Chinese mystery snail (Cipangopaludina chinensis) shells collected from South Korea to evaluate large-scale spatial variabilities, interpret relationships among isotopic signatures of various sample types, and generate spatial distribution isoscapes reflecting the heterogeneity of isotopic signatures across South Korea. Non-parametric comparisons among environmental samples showed non-significant differences in their isotopic ratios. The Sr/Sr of plant and soil samples were strongly correlated (R = 0.93), suggesting that both reflect national-scale lithological properties. Similarly, the Sr/Sr of shells showed strong correlations with the Sr/Sr of both plant and soil samples (R = 0.90). The Sr/Sr signatures of environmental samples in this study aligned with expected Sr isotopic values and generally reflected local geology. Spatial distribution maps of samples showed similar Sr/Sr spatial patterns, with high radiogenic values from granitic and granitic gneiss rocks systems and low radiogenic values from volcanic and sedimentary rock systems. Stream water samples showed significant correlations with soil and plant isotopic ratios, but with a low coefficient of determination (R = 0.68). The deviations were much larger for samples with Sr/Sr > 0.720. Further study is needed to improve the accuracy of baseline determination and interpretation of stream water isotopic variations.
成功应用和准确解释锶（Sr）同位素比值（Sr/Sr）需要了解各种环境样品中其特征的大规模变异性的基础信息，这些信息可与当地基础地质的Sr同位素特征相关联。在这项全国范围的研究中，我们分析了从韩国采集的土壤、植物、溪水和中华圆田螺（Cipangopaludina chinensis）贝壳中的Sr/Sr，以评估大规模空间变异性，解释各种样品类型的同位素特征之间的关系，并生成反映韩国同位素特征异质性的空间分布等值线图。环境样品之间的非参数比较显示其同位素比值没有显著差异。植物和土壤样品的Sr/Sr高度相关（R = 0.93），表明两者都反映了全国范围的岩性特征。同样，贝壳的Sr/Sr与植物和土壤样品的Sr/Sr都显示出很强的相关性（R = 0.90）。本研究中环境样品的Sr/Sr特征与预期的Sr同位素值一致，总体上反映了当地地质情况。样品的空间分布图显示出相似的Sr/Sr空间模式，花岗岩和花岗片麻岩岩石系统具有高放射性值，火山岩和沉积岩系统具有低放射性值。溪水样品与土壤和植物同位素比值显示出显著相关性，但决定系数较低（R = 0.68）。对于Sr/Sr > 0.720的样品，偏差要大得多。需要进一步研究以提高溪水同位素变化基线测定和解释的准确性。
