Estimation of the fertility of chernozem leached on the background of direct sowing of grain crops in the Southern Trans-Urals

The purpose of the research is a comprehensive assessment of changes in the fertility of leached chernozem against the background of direct sowing of agricultural crops. The aim of the research was to evaluate the agrochemical and agrophysical indicators of soil fertility with long-term use of direct sowing. The experience is based on the experimental field of the Chelyabinsk Scientific Research Institute of Agriculture in four-fold frequency on two backgrounds of mineral nutrition (with mineral fertilizer and without application). The purpose of the research is a comprehensive assessment of changes in the fertility of leached chernozem against the background of direct sowing of agricultural crops. The area of the elementary plot is 154 m2 . The accounting area is 64.4 m2 (2.3 m × 28 m). The studies were carried out in a grain-pair crop rotation with al-ternating crops of pairs-winter rye-peas+oats-wheat. In the third decade of May, the plots were treated with a continuous herbicide (glyphosate) and after 7 days, spring crops were sown. During the growing season, the crops were treated for weeds with the recommended selective preparations (Ballerina, Eraser-extra on wheat, Herbitox on peas). The agrochemical properties of the soil were determined by the following methods: humus and total nitrogen according to Tyurin, total phosphorus according to VOLE, mobile phosphorus and potassium exchange according to Chirikov and pH potentiometrically in a salt extract. For the agrophysical assessment, the classification proposed by N. I. Savvinov (1951) was used. During the studies, changes in the humus content occurred within the gradation for chernozem soils – average humus from 5 to 7 %. There were no significant changes in the reaction of the soil solution, it is characterized by slightly acidic, both be-fore the use of direct sowing, and after seven years. Changes рН in the background without mineral fertilizers from 5.37 to 5.47, with fertilizers from 5.08 to 5.22. The content of exchangeable potassium, mobile and total phosphorus increased on the backgrounds with and without fertilizers. The structural and aggregate state of the soil, the content of water-bearing aggregates, and the structural coefficient are assessed as good.