Changes in the properties of leached chernozems of the northern forest-steppe in the middle Ob River basin caused by different agricultural uses

Abstract

The trends of the soil-forming process and the changes in the main physicochemical properties of leached chernozems under different phytocenoses (virgin land, cereal-row crop rotation, and sown perennial grasses (Galega + Bromopsis)) were studied. In the cereal-row crop agrocenoses, as compared to the virgin land, the thickness of the humus horizon increased, and the depth of effervescence remained the same. The reaction of the leached chernozems in the phytocenoses did not change, and the sum of exchangeable bases increased in the following sequence: sown perennial grasses perennial grasses. On the contrary, the total phosphorus content, its mobility, the phosphorus capacity and reserves, and the sum of the mineral phosphates increased in the same order. The highest content of exchangeable potassium was found in the soils of the virgin land and the lowest one, in the soils of the cereal-row crop agrocenosis. The perennial grasses consumed the greatest amounts of potassium and nitrogen and the spring wheat of the cereal-row crop rotation, those of nitrogen. The removal of nitrogen was 1.6–1.8 and 2.3 times greater than the losses of phosphorus and potassium, respectively.