Kopchuk K. M. Productivity of short-rotational crop rotations depending on the fertilization system in the conditions of the Left Bank Forest-Steppe of Ukraine. - Qualifying scientific work on the rights of manuscripts.
The dissertation on competition of a scientific degree of the doctor of philosophy on a specialty 201 - agronomy (20 Agrarian sciences and food). - Institute of bioenergy crops and sugar beet of the National Academy of Sciences of Ukraine, Kyiv, 2023.
It was investigated that at the time of sowing of winter wheat, the available moisture reserves in the soil were most significantly influenced by weather conditions, and the predecessor and the predecessor's fertilization system had deviations within the limits of experimental error. Thus, in 2018, the 0-50 cm soil layer contained 8.7 mm of moisture, and in 2019 – 5.8 mm, which was not enough to obtain friendly seedlings and only the presence of precipitation allowed to obtain wheat crops. And in the conditions of the fall of 2020, the 0-50 cm soil layer contained 13.2 mm of moisture, which is why we got uniform wheat seedlings. Also, in the chain of crop rotation: winter wheat, sugar beets, barley, vetch - oats (siderate) in the soil layer 0-50 cm, the average moisture reserves were 10.2 mm, in the chain: winter wheat, sugar beets, barley, peas for grain 8.0 mm, and in the link: winter wheat, sugar beets, barley with subsowing, perennial grasses - 9.4 mm.
During the sowing period, under the conditions of 2019, the reserves of productive moisture in the 0-50 cm soil layer amounted to 73.5 mm of moisture, and 67.5 mm was available in the 50-100 cm layer, and in total, the 0-100 cm soil layer contained 140.9 mm of moisture. That is, moisture reserves can be assessed as good in general and suitable for growing most agricultural crops and satisfactory for growing sugar beets, since it is believed that at the time of sowing, there should be at least 180 mm of moisture available to plants in a meter layer of soil. In 2020, on average, according to the experiment, there was 81 mm of moisture in the 0-50 cm soil layer, and 62.1 mm was available in the 50-100 cm layer, and a total of 143.1 mm of moisture was contained in the 0-100 cm soil layer. And in 2021, there was 82.3 mm of moisture in the 0-50 cm soil layer, 66.6 mm was available in the 50-100 cm layer, and a total of 149.0 mm of moisture was contained in the 0-100 cm soil layer.
It was investigated that different crop rotation options did not significantly affect the change in productive moisture reserves in sugar beet crops at the time of harvesting. But on average, according to the crop rotation, when using N60P60K60 during the harvesting of sugar beets, the moisture reserves were smaller in the 0-50 cm soil layer by 2.64 mm, and in the 50-100 cm soil layer - 0.80 mm, and the total - 3.44 mm. While the use of N120P120K120 fertilizer at the time of harvesting resulted in more significant deviations in available moisture and in the 0-50 cm soil layer, the moisture reserves were 5.47 mm less, and in the 50-100 cm soil layers - 2.16 mm, and the total - 7.62 mm than on variants of basic fertilizer.
It was investigated that, in general, crop rotations had a slight effect on indicators of the content of easily hydrolyzed nitrogen under sugar beets. So, in the chain: vetch - oats (siderate), winter wheat, sugar beets, barley, the content was 145.7 mg/kg in the 0-50 cm soil layer, and 107.3 mg/kg in the 50-100 cm layer, and in the chain of crop rotation: peas for grain, winter wheat, sugar beets, barley, quite close indicators of the content of easily hydrolyzed nitrogen were obtained in the layer 0-50 cm - 145.7 mg/kg, and in the layer 50-100 cm - 105.7 mg/kg in accordance. But in the chain of crop rotation: perennial grasses, winter wheat, sugar beets, barley with undersowing, the content of easily hydrolyzed nitrogen in the layer 0-50 cm was 5.0 mg/kg, and in the layer 50-100 cm it was 3.3 mg/kg more than in the link with siderats.
