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The results of 8-variable column experiment on a strongly acidic sod-podzolic sandy loam reclaimed by the finely ground dolomite in a wide dose range are presented. The aim of the research was to measure and estimate leaching of magnesium (Mg) and its migration pattern. The dolomite powder at the different doses calculated by hydrolytic acidity (Hy) was applied at 225, 337.5, 450, 675, 900, 1350 and 1800 mg, that corresponded to 0.5, 0.75, 1.0, 1.5, 2.0, 3.0 and 4.0 Hy, respectively. The migratory ability of Mg was studied in 12-times washing column experiment. Each washing was carried out by 400 ml distilled water, simulating the volume of annual precipitation percolating through the soil stratum yearly. The increase in the amount of leaked moisture contributed to the enhancement of the eluvial losses of Mg. The maximum loss of Mg due to migration was established in the filtrates of the first washing. As the dose of dolomite increased, the amount of the soil Mg migrating with the total amount of Mg decreased from 27% to 7.5%. Complete removal of water-soluble Mg from the soil was not achieved in any of the studied treatments. Applied empirical estimations correctly described the process of leaching of Mg during repeated washing of the soil. Based on the data on the amount of leached Mg from soil reclaimed by a wide range of dolomite doses, a clustering of the empirical equations was performed. It was shown that in the 1 st stage of the experiment (from 1 to 4 washings) the rate of Mg leaching increased significantly with an increase in the dose of the dolomite. In the 2 nd stage (4 to 12 washings) such a pattern was not established. Depending on the dolomite dose applied, the losses of Mg increased from 14.05 to 50.6 mg compared to 3.8 mg in the non-limed (control) treatment. The main finding is that finely ground dolomite in an amount exceeding a full dose calculated by 1 Hy applied to sod-podzolic forest soil resulted in unproductive losses of Mg, i.e., with increasing dolomite dose, the losses of Mg increased.

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In an experiment carried out on Soddy-podzolic soil, limed with conversion chalk in a wide range of doses, the rate of dissolution of strontium-containing chalk and its effect on soil and plant were studied. Here we show that the complete decomposition of chalk applied to soil is achieved in the 3-4 years after its application. Increase in the concentration of plant available strontium in soil lasts until the chalk is completely dissolved. The dose of applied chalk determined the assimilation of strontium by rapeseed plants. We have found differences in accumulation of strontium by rapeseed in the year of application of chalk and in the third and fourth year of its aftereffect. We conclude that chalkmeliorated soil will generate strontium streams into plants for a longer period. We further propose empirical models that adequately describe: a) the processes of chalk dissolution in the soil; b) the dynamics of the content of strontium compounds accessible to plants in the process of interaction between chalk and soil; c) strontium accumulation in vegetative mass of rapeseed at different stages of chalk dissolution.

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Losses of soil calcium due to migration from Umbric Albeluvisols Abruptic soil meliorated by various doses of chalk were studied in column experiment with 16 washings. It has been established that the dynamic of calcium leaching from soil limed with optimal dose (1) and increased dose (2) is of a similar nature. In both treatments in the first 5 and 3 washes, respectively, there was a sharp decrease in the amount of calcium in the soil as described by exponential model. Starting from 6 and 4 washes, respectively, stabilization in Ca losses occurred. It was found that an increase in the chalk dose by 2.7 times increases the leaching of calcium by 4.8 times. It was concluded that an attempt to create in soil a certain reserve of available calcium for plants by increasing the dose of a finely ground ameliorant is ineffective because it increases unproductive losses of calcium. It has been suggested that in the soil there is a buffer system: exchangeable calcium ↔ calcium of soil solution, which even in the conditions of intensive wetting maintains the presence of a certain amount of water-soluble calcium.