The effect of mineral fertilizers and long-term aftereffect of liming on the biological properties of light gray forest soil and the yield of meadow clover 1g .p. in the conditions of the South-East of the Volga-Vyatka region

Abstract
The article deals with the influence of mineral fertilizers and the long-term aftereffect of liming on the biological properties of light gray forest soil and the yield of meadow clover 1 g.p. in the conditions of the South-East of the Volga-Vyatka region. The biological properties of light gray forest soil in 2020 were more influenced by the weather conditions of the pink clover vegetation and the culture itself than by the studied aftereffects of lime material and various doses of its mineral nutrition. The biological activity of the soil was in the range of 16.3–30.4%. The intensity of soil respiration was very weak and was in the range of 1.53–3.4 mg of CO2/10g for 24 hours. The average yield of the green mass of clover 1 g.p. (in terms of absolutely dry matter) was in the range of 30.4–33.2 t/ha (NSR05 by factor B-6.3) and did not depend on the aftereffect of the studied lime doses. The use of N45P120K180 doses of mineral fertilizers increases the average yield of pink clover 1 g.p. compared with the natural fertility of light gray forest soil and the variants of using N15P40K60 doses up to 37.9 t/ ha, which is by11.9 and 8.6 t/ha respectively higher than these variants (NSR05 for factor A-5.2). An increase was also obtained from the use of N30P80K120 doses of mineral fertilizers compared to the cultivation of clover according to natural soil fertility — by7.4 t/ha (NSR05 according to factor A-5.2).I n general, for 42 years of studying the aftereffect of liming it was shown, that by 2020 liming does not affect the biological properties of light gray forest soil and the yield of 1 g.p. clove according to all the studied doses of its use in the conditions of the South-East of the Volga-Vyatka region. The soil needs repeating of reclamation works.