The humus regime of typical chornozem in short crop rotations with different leguminous components

Abstract

Goal. To study changes in the humus state of typical chornozem during 13 rotations of field short crop rotations with different leguminous components. Methods. General scientific and special for agricultural science: long-term field and analytical. To determine the content of total humus in a typical chornozem, they used I.V. Tiurin’s method in Simakov’s modification, the humus balance was calculated according to the methodology of the Institute of Soil Science and Agrochemistry named after O.N. Sokolovskyi. Results. The analysis showed changes in the content of total humus in the soil depending on the crops grown during 13 rotations of short crop rotations in the Left Bank Forest-Steppe of Ukraine at the experimental field of the Kharkiv National Agrarian University named after V.V. Dokuchaiev. A positive effect of peas and grass pea on the content of humus in the arable layer of typical chornozem in crop rotations was revealed, in which this indicator was 4.39 and 4.34%, respectively, compared to paired crop rotation on average 0.34% higher. In field crop rotations with a vetch-oats mixture and soybean, this indicator exceeded steam crop rotation by 0.11%, but they were inferior to crop rotations with peas and grass peas in terms of humus content in the soil, the average difference was 0.13%. The balance of humus in the soil of the investigated organic agroecosystems with different plant components was passive and varied from –109 to –635 kg/ha. The humus deficiency was smaller in field crop rotations with leguminous crops (vetch in a mixture with oats, soybeans, peas, lentils, beans, and grass peas) for growing buckwheat in the 3rd year of the rotation. Conclusions. A higher content of humus in the soil was found in crop rotations with leguminous crops and corn for silage. A noticeable decrease in the content of organic matter in the soil due to the introduction of pure steam into organic agroecosystems was noted. The balance of humus in the soil of the investigated crop rotations with different plant components was passive. A smaller humus deficit was observed in crop rotations with leguminous crops for growing buckwheat in the 3rd year of the rotation.