Effect of Long-Term Use of Straw and Siderates on Gray Forest Soil on the Productivity of Agrocenoses

A study in a stationary field experiment on gray forest soil of the Tomsk region proved the advantage of biologization of agriculture with the use of biological resources of agrocenoses (straw and siderates) in the grain-steam crop rotation. Regular application of only N45 before sowing provided an average increase in grain yield of 4.3 c/ha (by 26%), straw without nitrogen – by 1.3 c/ha (by 7.5%). When applying straw with nitrogen for 20 years, an increase in yield was obtained, not exceeding the total effect of nitrogen and straw – 5.1 c/ha (by 30.7%). The use of sideral steam against the background of regular application of straw provided an increase in the yield of grain crops by 3.8 c/ha (by 22.4%). After 20 years of the experiment, the average humus content in the arable horizon decreased by 9.6% from the initial when using pure steam without fertilizers. In order to preserve the potential fertility, the introduction of only straw and (or) mineral nitrogen in this case was also insufficient. At the same time, the lateral steam and regular application of straw ensured the preservation of the humus content in the arable horizon at the initial level. During 4 rotations (2001–2021) of the grain-steam crop rotation, the increasing efficiency of sideral steam was noted against the background of regular use of straw as fertilizer compared to the pure steam variant: in the 1st rotation, the yield of grain crops in these variants was at the same level, in the 2nd – the yield after sideral steam was 11.7 more% more than after pure steam, in the 3rd rotation – respectively 18% more, and in the 4th rotation, sideral steam provided better grain yields than after pure steam (an increase of 36.5%).