Shishkina E A, Starichenko V I, Valeeva E R, Lyubashevsky N M, Modorov M V
Urals Research Center for Radiation Medicine (URCRM), Chelyabinsk, Russia; Chelyabinsk State University (ChelSU), Chelyabinsk, Russia.
Institute of Plant and Animal Ecology, Ural Division, Russian Academy of Sciences, ul. Vos'mogo Marta 202, Yekaterinburg, 620144 Russia.
J Environ Radioact. 2021 Aug;234:106628. doi: 10.1016/j.jenvrad.2021.106628. Epub 2021 May 13.
The dynamics of rodent population in the area of East Urals Radioactive Trace (EURT) is one of the controversial issues, which are of key importance for the radiobiological and radioecological interpretation of the observed radiation effects. The objective of the paper is to evaluate the probability of migration in population of the herb field mouse (Sylvaemus uralensis Pall., 1811) based on Sr activity concentrations in the mouse bones. Radiometric data for bones of 768 mice captured at 9 sites in the EURT territory (with different environmental contamination levels) in 2001-2012 were used. The distribution of bone-seeking Sr in the juvenile age group of mice is used as a model of the width of radionuclide distribution in the bones of permanent inhabitants. Comparison of the model predictions and observations in different age and functional groups within the population structure allows simulating the probability of migration and evaluating the fraction of migrants. It is shown that the accumulation of Sr in bones correlates with soil contamination at the capture sites. Individual variability in the specific activity of Sr in the skeleton tends to increase with the age of animals. The rate of herb field mouse migration is estimated as 7 and 15% per year (for underyearlings and wintered individuals, respectively). The animals captured in the EURT area (all animals, including juvenile individuals) are "diluted" with animals from non-contaminated territories by 5-12%. The average half-time of substitution of the exposed population by migrants from non-contaminated territories is 8 years. Today, the fraction of descendants of the animals, that for generations have permanently inhabited the EURT territory since 1957, is negligible (on average-1.2% and not exceeding 17%). The proposed method of probabilistic analysis of Sr in the bones could be used to study migration activity of other species of rodents.
东乌拉尔放射性踪迹（EURT）地区啮齿动物种群动态是一个颇具争议的问题，对于所观察到的辐射效应的放射生物学和放射生态学解释至关重要。本文的目的是基于小鼠骨骼中的锶活度浓度，评估草甸田鼠（Sylvaemus uralensis Pall., 1811）种群迁移的可能性。使用了2001年至2012年在EURT地区9个地点（具有不同环境污染水平）捕获的768只小鼠骨骼的放射性数据。小鼠幼年年龄组中骨亲和性锶的分布被用作永久居民骨骼中放射性核素分布宽度的模型。通过比较种群结构中不同年龄和功能组的模型预测结果与观测结果，可以模拟迁移的可能性并评估迁移个体的比例。结果表明，骨骼中锶的积累与捕获地点的土壤污染相关。骨骼中锶比活度的个体变异性往往随着动物年龄的增长而增加。草甸田鼠的迁移率估计分别为每年7%和15%（对于未成熟个体和越冬个体）。在EURT地区捕获的动物（所有动物，包括幼年个体）被来自未受污染地区的动物“稀释”了5%至12%。未受污染地区的迁移者替代受辐射种群的平均半衰期为8年。如今，自1957年以来世代永久居住在EURT地区的动物后代比例可以忽略不计（平均为1.2%，且不超过17%）。所提出的骨骼中锶的概率分析方法可用于研究其他啮齿动物物种的迁移活动。
