Influence of the Fertilization System on Fertility Indicators of Sod-Podzolic Heavy Loamy Soil in the Pre-Urals

Abstract

The effect of long-term usage of various fertilization systems (organic, mineral, and organic-mineral) on the agrochemical indicators of sod-podzolic heavy loamy soil and the productivity of crops of eight-field crop rotation has been studied. Fertilization systems with high saturation (manure 20 t/ha per year, NPK in equivalents of manure 20 t/ha per year, and manure 10 t/ha per year + NPK in equivalents of manure) provided a significant increase in soil humus content (from 1.97 to 2.23–2.50%), mobile phosphorus (by 120–145 mg/kg), and exchangeable potassium (by 105–163 mg/kg) as well as increase in total, mineral, and hydrolyzable nitrogen content (by 200–360, 1.3–2.3, and 53–65 mg/kg, respectively). Cattle manure contributes to a decrease in hydrolytic acidity from 2.3 to 1.5–1.8 and to an increase in the amount of exchange bases from 18.2 to 20.8–21.9 mmol/100 g of soil. NPK treatment (in equivalents of manure 20 t/ha per year) leads to an increase in the hydrolytic acidity by 1.0 and to a decrease in the total exchangeable bases by 1.1 mmol/100 g. The maximum productivity of arable land (3800 fodder units per ha) has been obtained under fertilization systems NPK equivalent to manure 20 t/ha per year and manure 10 t/ha per year + NPK in equivalents of manure.