Kudelsky A V, Smith J T, Ovsiannikova S V, Hilton J
Institute of Geological Sciences, Academy of Sciences of Belarus, Republic of Belarus.
Sci Total Environ. 1996 Oct 11;188(2-3):101-13. doi: 10.1016/0048-9697(96)05162-5.
The behaviour of Chernobyl-derived 137Cs in a hydrologically isolated bog system in the catchment of the Pripyat River, Belarus was investigated. Measurements were made of 137Cs activities in the solids and pore waters of the bog soils, as well as the variability in activity in water draining from the bog. It was found that the radiocaesium activity of the pore water, and hence the measured distribution coefficient, Kd, was dependent upon the pressure at which the water was removed from the soil. Measured values of Kd were of the order 10(2) l/kg at an extraction pressure of 0.8 MPa, approximately one order of magnitude lower than those measured in a similar system, Devoke Water, in the UK [1]. Results of comparative measurements suggested that this was a result of the different pore water extraction techniques used. The vertical migration of radiocaesium was modelled using a solution of the advection-diffusion equation. Using a mass balance approach, it was estimated that 137Cs was removed from the system at a rate of 0.3% of the catchment inventory per year, approximately 8 years after the Chernobyl accident. It was shown that both vertical migration and removal of 137Cs is best modelled using a Kd based on a measurement of pore water held at low pressure in the soil, approximately 10(3) l/kg. 137Cs activities in soil pore waters and in drainage waters were very strongly related to the aqueous potassium concentration, and both showed concentration minima in drainage water during the spring. It was shown that runoff coefficients of radiocaesium from peat bogs 8 years after the Chernobyl accident were approximately one order of magnitude greater than those from unsaturated soils of higher mineral content.
对白俄罗斯普里皮亚季河流域一个水文孤立的沼泽系统中切尔诺贝利事故产生的¹³⁷Cs的行为进行了研究。测量了沼泽土壤固体和孔隙水中的¹³⁷Cs活度，以及从沼泽排出的水中活度的变化。研究发现，孔隙水的放射性铯活度以及由此测得的分配系数Kd取决于从土壤中取水时的压力。在0.8MPa的提取压力下，测得的Kd值约为10²l/kg，比在英国类似系统德沃克湖[1]中测得的值低约一个数量级。对比测量结果表明，这是由于所采用的不同孔隙水提取技术导致的。利用平流扩散方程的解对放射性铯的垂直迁移进行了建模。采用质量平衡方法估计，在切尔诺贝利事故发生约8年后，¹³⁷Cs从该系统中去除的速率为集水区存量的每年约0.3%。结果表明，¹³⁷Cs的垂直迁移和去除最好使用基于土壤中低压孔隙水测量值的Kd进行建模，约为10³l/kg。土壤孔隙水和排水水中的¹³⁷Cs活度与水中钾浓度密切相关，且两者在春季排水水中均出现浓度最小值。研究表明，切尔诺贝利事故发生8年后，泥炭沼泽中放射性铯的径流系数比矿物质含量较高的非饱和土壤中的径流系数大约高一个数量级。
