Content analysis on basic nutrients in soil when growing sainfoin in the Lower Volga region

Abstract

Abstract The article presents the results of studies evaluating the effect from using organic fertilizers or doses, equivalent to them, of mineral fertilizers; how presowing seed treatment with using bischofite impacts the dynamics of the main nutrients (nitrogen, phosphorus, potassium) in the arable and subsurface layers of soil when sowing the sandy sainfoin under the irrigation. It is shown that in all options of organic and mineral fertilizers by the end of the vegetation season of the sainfoin growing, there was observed phosphorus content decrease, in both the arable and subsoil layers of the soil. In the subsurface layer, the deficiency of the mobile phosphorus reached 70 % in the control option and in the option with the mineral fertilizers, whereas in the options with the organic fertilizers this deficiency was limited to 40 %. The dynamics of the nitrogen was not negative after three years; the content of this element practically remained at the initial level, having decreased only by 10 %. The dynamics of the potassium in the arable layer of the soil was also not negative, and in the subsurface layer the content of this element slightly decreased.