THE EFFECT OF TIME FACTOR AND DEPTH OF STRONTIUM-90 IN SOIL ON ITS ACCUMULATION IN SUPER-PREKOS APPLE-TREE
The problems of returning radioactively contaminated lands to agricultural production are of strategic importance for any country especially when the areas of fertile lands are limited. The research goal was to study the effect of time factor and the depth of strontium-90 occurrence in soil to its accumulation in the apple-tree variety Super Prekos (Stark Earliest). The research objectives were as following: 1) to study the effect of time and depth of strontium-90 occurrence in the soil to its accumulation in the vegetative organs of Super Prekos apple-tree variety; 2) to determine the effect of time and depth of strontium-90 occurrence in the soil to its accumulation the generative organs of Super Prekos apple-tree variety. The appropriate research techniques were chosen. The data on strontium-90 accumulation in the bark and wood of Super Prekos apple-tree depending on the depth of its occurrence in the soil was obtained through a field experiment. The greatest accumulation has been found in the variant of the nuclide depth in the soil of 50 cm. It has been found that over time the content of strontium-90 in the bark and wood decreases but the decrease dynamic is different depending on its occurrence depth in the soil. Special attention was paid to the radionuclide accumulation in the fruits. The difference in strontium-90 accumulation in the pericarpium and seeds of Super Prekos apple-tree variety depending on the depth of the nuclide occurrence in the soil has been proved. Greater accumulation in fruits has been found with the nuclide depth in the soil of 50 cm which has been confirmed mathematical data processing. For the first time in the field conditions scientific data on strontium migration from the soil to Super Prekos apple-tree variety have been experimentally obtained. The effect of time factor and depth of strontium-90 occurrence in soil on the radionuclide accumulation in the vegetative and generative organs of the apple-tree has been proved.