Application of nitrogen-sulfur fertilizers as a way to reduce the impact of soil agrophysical properties on agrocenosis yielding capacity

Abstract

Soil physical properties determine its water and air balance and the accessibility of nutrients to plants. Modern trends in minimal tillage are driven first and foremost by the goal of cutting economic expenses, whereas the problem of overcoming the negative effects on soil physical structure, and therefore on crop yields, has yet to be solved. The research conducted from 2021 through 2023 in the steppe zone of the Saratov Region focused on the potential to mitigate the impact of soil bulk density on crop yields. The framework of the research was the geosystems of the facies ranking which also served as the sampling sites. It was found that in well-structured (K_st ≈ 3.1) chernozems of the northern steppe, a higher physical sand fraction (R² = 0.70) significantly lowers bulk density (R² = 0.83, R = 0.6). In contrast, in less-structured (K_st ≈ 1.11) kashtanozems of the arid steppe, bulk density increases (R² = 0.83) as the physical sand content rises (R² = 0.76, R = 0.65). Based on linear regression equations for various agrochemical (N-NO₃, P₂O₅, K₂O, SO₄, humus, pH) and agrophysical (soil bulk density) factors, it was concluded that soil bulk density had a substantial (>50%) effect on spring soft wheat yields in the main soil types of the steppe zone. Furthermore, agricultural intensification through the application of nitrogen and nitrogen-sulfur fertilizers markedly reduced the extent of this effect from 75% to 65% on chernozems and from 50% to 13% on kashtanozems.