Salbu B, Oughton D H, Ratnikov A V, Zhigareva T L, Kruglov S V, Petrov K V, Grebenshakikova N V, Firsakova S K, Astasheva N P, Loshchilov N A
Isotope and Electron Microscopy Laboratories (ISEM), Agricultural University of Norway, Aas.
Health Phys. 1994 Nov;67(5):518-28. doi: 10.1097/00004032-199411000-00007.
Results are presented from studies concerning the behavior of the Chernobyl-derived radionuclides 137Cs and 90Sr in soil-plant agricultural systems in the Ukraine, Belarus, and Russia during 1991. The sites, representing ploughed and natural pastures, were located at varying distances between 50 and 650 km and varying directions from the Chernobyl reactor site. The 137Cs activity concentrations in the upper 0-5 cm soil layer ranged from 25-1,000 kBq m-2 and were higher in natural pastures as compared to ploughed pastures. For 90Sr, activity levels ranged from 1.4-40 kBq m-2, and the highest 90Sr deposition was observed in the Gomel Region, Belarus. The highest 90Sr: 137Cs ratio was also observed in the Gomel soils, i.e., 15% as compared to between 0.72 and 7.4% in the other soils. The mobility of radionuclides was studied by means of sequential extraction. For all soils, between 60 and 95% of the 137Cs was found to be strongly bound to soil components. In the Russian and Ukrainian soils, between 40 and 98% of the 90Sr was found in the easily extractable fractions, and the distribution of 137Cs and 90Sr followed that of the naturally occurring stable isotopes of cesium and strontium. However, in the Gomel soils, between 20 and 50% of the 90Sr was easily extractable and the distribution of 90Sr within the extraction fractions did not follow that observed for stable strontium. These results are thought to reflect the association of 90Sr with fuel particles deposited in the Gomel Region. The mobility of 90Sr is expected to increase with time (as the particles weather) in these soils.
本文展示了1991年乌克兰、白俄罗斯和俄罗斯土壤-植物农业系统中切尔诺贝利衍生的放射性核素137Cs和90Sr行为的研究结果。这些代表耕地和天然牧场的地点距离切尔诺贝利反应堆站点50至650公里不等，方向各异。0-5厘米上层土壤层中137Cs的活度浓度范围为25-1000 kBq m-2，天然牧场中的浓度高于耕地牧场。对于90Sr，活度水平范围为1.4-40 kBq m-2，白俄罗斯戈梅利地区观测到最高的90Sr沉积。戈梅利土壤中还观测到最高的90Sr:137Cs比率，即15%，而其他土壤中的该比率在0.72%至7.4%之间。通过连续萃取研究了放射性核素的迁移性。对于所有土壤，发现60%至95%的137Cs与土壤成分紧密结合。在俄罗斯和乌克兰的土壤中，40%至98%的90Sr存在于易萃取部分，137Cs和90Sr的分布与铯和锶的天然稳定同位素分布一致。然而，在戈梅利土壤中，20%至50%的90Sr易于萃取，且90Sr在萃取部分内的分布与稳定锶的观测分布不同。这些结果被认为反映了90Sr与戈梅利地区沉积的燃料颗粒的关联。预计随着时间推移（随着颗粒风化），这些土壤中90Sr的迁移性会增加。
