Вплив диференціації азотного удобрення темно-каштанового солонцюватого ґрунту на його агрохімічні показники та врожайність сільськогосподарських культур

Abstract

Goal. To establish features of the influence of differentiation (address rationing) of mineral nitrogen fertilizers application on agrochemical indicators of dark chestnut weakly alkaline soil (the content of mineral nitrogen and humus) and crop yield. Methods. Field — to study the effect of gypsum and nitrogen fertilizer on the properties of dark chestnut soil and crop yields, laboratory analysis — o determine the content of mineral nitrogen and humus, mathematical — to assess the reliability of research results. Results. The application of mineral nitrogen fertilizers has led to a tendency to increase the content of mineral nitrogen in dark chestnut weakly alkaline soil. Fertilization and cultivation of crops did not affect the variability of mineral nitrogen content, which in general in the experiment remained moderate, the coefficient of variation did not change. Although the average amount of nitrogen fertilizer applied to the plots in the variant of differentiated application is 92.1 kg/ha, was less than in the plots with the maximum level of fertilizer, the yield did not differ from that with the maximum level of application and was reliably higher than in the variant with the average level of application. Conclusions. It is established that under the influence of growing crops and applying nitrogen fertilizers, the supply of dark chestnut weakly alkaline soil with mineral nitrogen improves at medium and maximum levels of fertilizer. It is established that the lack of fertilizer or low doses of nitrogen fertilizers increase the variability of the soil in terms of mineral nitrogen content, and the high level of application (390 kg/ha) for 6 years under 3 crops equalizes this indicator. There was a decrease in the variability of dark chestnut weakly alkaline soil in terms of humus content in the arable layer. A stable significant increase in the yield of grain and fodder crops depending on the levels of nitrogen fertilizer application has been also established. Differentiation of nitrogen fertilizers allows saving nitrogen fertilizers in the amount equivalent to almost 15 kg/ha of active substance per year in grain-feed 6-field crop rotation in the absence of a significant reduction in yield on dark chestnut weakly alkaline non-irrigated soils.