Changes in the Agrochemical Properties of Soddy-Podzolic Soil under the Impact of Long-Term Application of Fertilizers

The influence of long-term application of organic and mineral fertilizers on the changes of soddy-podzolic soil (Glossic Retisol (Loamic, Aric)) properties was studied. These were: organic carbon content, available nitrogen and phosphorus, and soil exchange complex. The studies were carried out in one-meter soil layer in a long-lasting stationary experiment established in the Perm region in 1976. It was determined that mineral fertilizer use during five rotation cycles of the seven-course crop rotation increased significantly the contents of hydrolyzed nitrogen and available phosphorus; the 1.2–2.6 times increase in comparison with control was found for the whole profile. hydrolyzed nitrogen pool increased in the plow layer from 0.3 to 0.4 t/ha, in one meter-thick layer – from 1.3 to 1.6 t/ha, that of available phosphorus – from 0.3 to 0.8 t/ha and 3.1 to 4.8 t/ha, respectively. The increase of organic matter content was found only for 20–40 cm layer. The systematic application of mineral fertilizers promoted a significant decrease of actual and total acidity throughout the whole profile. Cattle manure application (5.7 t/ha) resulted in the improvement of soil exchange complex parameters: an increase in base saturation to a depth of 60 cm. Hydrolyzable and mineral nitrogen contents increased as well as phosphate mobility in the upper soil layer (0–20 cm), the organic carbon content increased insignificantly. Only the combined application of cattle manure and mineral fertilizers increased significantly the content of organic matter in the soil by 1.2–1.6 times in the upper and underlying layers, and provided the recovery of its initial content. Organic carbon pool increased from 28.3 to 32.2 t/ha in the 0–20 cm layer and from 71.5 to 81.8 t/ha in one-meter layer. Cattle manure application reduced the negative effect of mineral fertilizers on soil acidity.