Centre for Nuclear and Accelerator Technologies (CENTA), Faculty of Mathematics, Physics and Informatics, Comenius University, 842 48 Bratislava, Slovakia.
Department of Radiation Dosimetry, Nuclear Physics Institute, Czech Academy of Sciences, 180 86 Prague, Czech Republic.
J Environ Radioact. 2020 Jul;218:106237. doi: 10.1016/j.jenvrad.2020.106237. Epub 2020 Apr 17.
In order to study radiocarbon levels at a clean air location in Slovakia with no significant local anthropogenic effects, we took tree ring samples from a tree in the vicinity of Jasná recreational area in the Low Tatras region in the central part of Slovakia. There are no significant local fossil fuel emission sources, so these samples represent a regional clean air background important for C studies in Slovakia and Central Europe. The growth rings from the sampled tree (European spruce, Picea abies) cover the period from 1911 to 2016. The first part of the data (1911-1952) represents natural radiocarbon levels influenced by Suess effect. The following period exhibits an increase in radiocarbon levels due to atmospheric nuclear weapons tests (ΔC maximum of 850‰ in 1964), and then a gradual decrease characterized by an exponential trend with time constant of 14.3 ± 0.5 years. The ΔC data from Jasná was used as a reference for comparison with two previously reported modern tree ring data sets from Slovakia. This comparison showed that radiocarbon levels at both locations are lower than clean air reference values, indicating the influence of local fossil fuel emissions.
为了研究斯洛伐克一个没有显著本地人为影响的清洁空气地点的放射性碳水平，我们从斯洛伐克中部分塔特拉山脉亚斯纳度假区附近的一棵树的年轮中采集了样本。这里没有显著的本地化石燃料排放源，因此这些样本代表了一个对斯洛伐克和中欧的 C 研究很重要的区域清洁空气背景。所采样树木（欧洲云杉，Picea abies）的生长年轮涵盖了 1911 年至 2016 年的时期。数据的前一部分（1911-1952 年）代表受苏斯效应影响的自然放射性碳水平。随后的时期由于大气核武器试验导致放射性碳水平增加（1964 年最大增加 850‰），然后以时间常数为 14.3±0.5 年的指数趋势逐渐下降。亚斯纳的 ΔC 数据被用作与斯洛伐克之前报告的两个现代树木年轮数据集进行比较的参考。这一比较表明，两个地点的放射性碳水平都低于清洁空气参考值，表明受到了本地化石燃料排放的影响。
