METHOD OF LIMING DRAINED MINERAL SOILS Russian patent published in 2015 - IPC E02B11/00 A01B79/02 G01N33/24 

FIELD: agriculture.

SUBSTANCE: method comprises application into the soil of calcareous material providing neutralization of complete hydrolysis acidity at a dose D of clean dry CaCO₃, t/ha, determined by a mathematical formula in the application documents, taking into account hydrolytic acidity, power of the limed layer and soil density. The dose D of clean dry CaCO₃, t/ha, is recalculated in the physical quantity D_ph of the calcareous material applied to soil. The dose D of clean dry CaCO₃, t/ha, is increased by the value of ΔD, taking into account the average annual removal of calcium carbonates with drainage runoff for the period T (years) between the previous and subsequent soil liming. Recalculation of the dose D in the physical quantity D_ph and determining the value ΔD is carried out also according to mathematical formulas given in the application documents. In calculation of the dose D clean dry CaCO₃, t/ha, for neutralization of complete hydrolysis acidity the values average weighted on the limed area of hydrolytic acidity, the layer thickness and density of the soil are taken. Liming of drained mineral soils is carried out by calcareous materials containing magnesium, replenishing thus the loss of magnesium fertilizers with the drainage flow, determined by the formula given in the application documents, and for drained sod-podzol average-cultured loamy gleysolic soil on the cover loam used in the system of grain-flax- grass crop rotation, to calculate the removal of MgCO₃, t/ha, the coefficient of transition from the removal with drainage flow Mg2⁺to the removal of MgCO₃ µ=3.5, and to calculate the removal of Mg2⁺in kg/ha a=1.62, b=0.58. In the physical amount D_ph1 of calcareous material applied to soil, obtained also by a mathematical formula for the dose (D+ΔD) of clean dry CaCO₃, t/ha, the content of MgCO₃ is also determined, and comparing the loss of magnesium fertilizer with the drainage water with the content of MgCO₃ in the physical amount D_ph1 of calcareous material applied to soil, the need for additional application to soil of magnesium fertilizers in the use of drained mineral soils is determined.

EFFECT: liming, besides reduction of the acidity of the soil, eliminates the harmful effect of aluminium and manganese in the drained lands, increases the efficiency of fertilizers applied, contributes to soil structuring and improvement of subsurface drainage action, and ultimately increase in crop yields on drained mineral soils.

4 cl