CHANGE IN THE FERTILITY OF SOD-PODZOLIC SOILS UNDER THE CONDITIONS OF LONG APPLICATION OF ELEVATED NORMS OF FERTILIZERS
The investigations carried out at the Grodno State University have shown that the long use of organic, mineral and lime fertilizers on light sod-podzolic soils increases the content of humus by 0.46-0.63%, of total nitrogen - by 110-170 mg/kg, the number of movable forms of phosphorus is increased by 45-68, potassium - by 47-61 mg/kg of soil, magnesium and calcium - by 15-36%, copper, zinc and boron - by 50-143%. The activity of soil enzymes - catalases and cellulase enhances, the nitrification ability of soils grows. More essential changes in the soil fertility are found for sandy soil. However essential changes in the direction of soil processes when acted upon by fertilizers are not seen - the invariable structure of the nitrogen fund and the carbon-nitrogen relation in soils are preserved.