About the Journal

Authors:

E. V. KIRILLOVA, senior research associate,

A. N. KOPYLOV, candidate of agricultural sciences, leading research associate, head of the laboratory,

KURGAN RESEARCH INSTITUTE OF AGRICULTURE (9 Lenina Str., Sadovoe, 641325, Kurgan)

Abstract. The application of various doses of nitrogen and phosphorus fertilizers in a four–field grain–fallow crop rotation was investigated in long-term (45–46 years) experiments on leached chernozem of the experimental field of the Kurgan RIA. With the introduction of minimal tillage, the productivity of rotation of steam-3 wheat (VIII–XI rotations) was reduced compared to the period with plowing in the rotation of steam-2 wheat-oats (I–VII rotations) per 0.25–0.43 t gU/ha. The return of mineral fertilizers by the addition of grain increased, but with a monophosphorous fertilizer system, it increased in the onset of arid phenomena. Recommended moderate doses of fertilizers with long–term use changed the agrochemical properties of the soil. The sowing of phosphorus fertilizer P20 over 45 years promoted the cultivation of leached chernozem, since it increased the content of mobile phosphorus per 32–65 mg/kg of soil, which transferred the soil into a group with the raised and its high content. Minimization of soil cultivation contributed to its differentiation along the soil profile with accumulation mainly in the upper layer 0–10 cm. The potential acidity of the soil increased by 0.92–1.04 of the pH value when laying the test, but this happened in the control variant, where fertilizers was not introduced. The physiological acidity of fertilizers lowered the pH in salt extract only by 0.09–0.15 in 2016. Reduction of the amount of plant residues in VIII–XI rotations led to a decrease in the humus content relative to the level at the time of laying. The introduction of a nitrogen-phosphorus fertilizer stabilized the supply of organic matter to the soil. The decrease in humus content in the control and in the mononitric system is proved.