Nutrient Balance of Sod–Podzolic Soil Depending on the Productivity of Meadow Agrophytocenosis and Fertilization

Abstract

The influence of mineral fertilizers on productivity and nutrient balance of sod–podzolic soil when growing cereal meadow agrophytocenosis under conditions of Precarpathians of Ukraine was researched. It was found that the dependence of cereal agrocenosis productivity on the doses and ratios of N, P, K in mineral fertilizers is described by equation (polynomial) of the 2nd degree. Among the mineral elements, nitrogen is has the greatest influence on grass productivity. When applying the total dose of N75 with even distribution of nitrogen under each of three mowings on different backgrounds of phosphorus-potassium fertilizers, the productivity of cereal grass increases by 2.82–3.06 t ha-1 of dry mass, and when applying N150 by 3.33–4.93 t ha -1 of dry mass. Recoupment of nitrogen fertilizers per 1 kg by yield increase when applying N75 is 38–41 kg of dry mass, which is 4–5 kg more compared to the application of N150. The indices of phosphorus and especially potassium removal, as well as deficiency of these elements in the balance increased along with nitrogen dose. Independently of the phosphorus and potassium doses, the lowest indices are fixed on a nitrogen–free background, and the highest – on the background of N150.