Agrogenic Transformation of Soil Fertility of Leached Chernozem during Fertilization in the Beet Crop Rotation in the Central Chernozem Region

Long-term agricultural use of leached chernozem in the 9-pole grain-and-beet crop rotation of the forest steppe of the Central Chernozem Region without the use of fertilizers contributed to a significant deterioration in a number of indicators of soil fertility (a decrease in the content of humus, total nitrogen, mobile forms of PO and KO, deterioration of physic-chemical properties) relative to the virgin area. Prolonged application of fertilizers compensated for the loss of humus to varying degrees, contributed to the enrichment of mobile forms of PO and KO, but somewhat worsened the acid-base properties of the soil. The NPK fertilizer system + 5.6 t/ha manure made it possible to preserve soil fertility to the greatest extent, and some a number of indicators - almost at the level of virgin land. The greatest change in fertility was observed in the 0-20 cm layer, the smallest - in the 40-60 cm layer.