Temporary changes of radiological effectiveness of soil liming contaminated with Cs137 and Sr90 radionuclides

Analysis of coefficient of variation of radionuclide transfer into crops and determination of temporary changes of radiological effectiveness of lime application in soils polluted by Cs137 and Sr90 radionuclides was realized in the conditions of the Republic of Belarus. Dynamics of changes of Sr90 coefficient of variation taking into consideration the acidity of sod-podzolic sandy, loamy soils, as well as the dynamics of changes of Cs137 and Sr90 accumulation by crops depending on doses of ameliorants were found out in the experiment. Research result showed that over the last ten years the indices of Sr90 transfer in the majority of cases increased on the acidic sandy soils (on 38 %) and in a less degree (9 %) - on light loamy acid-free sod-podzolic soils. Effectiveness of the influence of soil acidity neutralization on lowering of Sr90 transfer did not stop over the time and did not depend on soil structure, but depended on its initial acidity. Liming of the medium acid soils till the optimal intervals of pH in 1989-1993 made it possible to lower the Sr90 transfer on 21-22%. Effectiveness of soil liming in 1999-2003 was 31-33%. In the stationary field experiments on sod-podzolic sandy soils realized in 2003-2006 it was found out, that the effectiveness and the aftereffect influence of the optimal and heightened doses of ameliorants on Cs137 transfer was a bit lower than in 1993-1995 while the transfer of Sr90 was higher on 23-31%