Nuclear Technology Laboratory, Department of Electrical and Computer Engineering, Aristotle University of Thessaloniki, GR-54124 Thessaloniki, Greece.
Industrial Engineering and Management Department, International Hellenic University, GR-57400 Thessaloniki, Greece.
Radiat Prot Dosimetry. 2023 Nov 16;199(19):2366-2372. doi: 10.1093/rpd/ncad241.
After the Chernobyl accident, a designated area of ~1000 m2 within the University farm of Aristotle University of Thessaloniki in Northern Greece was utilized as a test ground for radioecological measurements. The profile of 137Cs in the soil was monitored from 1987 to 2023, with soil samples collected in 5-cm-thick slices (layers) down to a depth of 30 cm. The mean total deposition of 137Cs in the area, backdated to the time of the Chernobyl accident, was determined to be 18.6 ± 1.8 kBq m-2 based on four follow-up profile measurements of 137Cs in the soil for the years 2022 and 2023. It is noteworthy that this value is similar the total deposition at the site, which was independently measured to be about 20 kBq m-2 during the first year after the Chernobyl accident. The fractional contribution of each soil layer (e.g., 0-5 cm, 5-10 cm, 10-15 cm, etc.) to the total deposition of 137Cs (0-30 cm) is presented and analyzed. A compartment model was utilized to forecast the temporal evolution of fractional contributions of the different soil layers to the total deposition of 137Cs (0-30 cm). In this model, each soil layer is represented as a separate compartment. The model assumes that the transfer rates between adjacent compartments are equal. The agreement between the measured fractional contributions and the model predictions suggests that the compartment model with equal transfer rates can capture the broad patterns of 137Cs migration within the soil layers over the long period of 1987-2023. However, the use of a second compartment model with increasing transfer rates between consecutive soil layers did not align with the observed outcomes. This indicates that diffusion may not be the primary migration mechanism over the 36-y period covered by our study.
切尔诺贝利事故后，希腊北部塞萨洛尼基亚里士多德大学的大学农场内约 1000 平方米的指定区域被用作放射性生态学测量的试验场。从 1987 年到 2023 年，监测了土壤中 137Cs 的剖面，采集了 5 厘米厚的土壤样本（层），深度达 30 厘米。根据 2022 年和 2023 年对土壤中 137Cs 进行的四次后续剖面测量，确定该地区 137Cs 的总沉积量回溯到切尔诺贝利事故发生时为 18.6±1.8 kBq m-2。值得注意的是，该值与该地点的总沉积量相似，该地点在切尔诺贝利事故发生后的第一年独立测量约为 20 kBq m-2。展示并分析了每个土壤层（例如，0-5 厘米、5-10 厘米、10-15 厘米等）对 137Cs 总沉积量（0-30 厘米）的分数贡献。利用隔室模型预测不同土壤层对 137Cs 总沉积量（0-30 厘米）的分数贡献的时间演变。在该模型中，每个土壤层表示为一个单独的隔室。该模型假设相邻隔室之间的转移速率相等。测量的分数贡献与模型预测之间的一致性表明，具有相等转移速率的隔室模型可以捕获 137Cs 在土壤层中迁移的大致模式，时间跨度为 1987-2023 年。然而，使用具有连续土壤层之间转移速率增加的第二个隔室模型与观察结果不一致。这表明扩散可能不是我们研究涵盖的 36 年期间的主要迁移机制。
