Measuring the content of phosphorus and potassium forms in soddy-podzolic soil and the productivity of crop rotation under long-term fertilization
Demin, V.A.; Audu, M.; Sharapova, A.V.; Povetkin, V.A.
Agrokhimiya 3: 18-26
Different fertilizer systems were used in crop rotation (annual grasses for hay, winter rye/winter wheat, potatoes, barley/winter wheat) for 25 years in soddy-podzolic, medium-loam soil. The method of differentiated standardized balance was used to calculate the fertilizer dose for an average annual application of 138, 263, 213, and 304 kg/ha of N, P2O5, and K2O as part of two mineral and two manure/mineral fertilizer systems. The resulting productivity was 5.5, 6.7, 6.4, and 7.2 tons of fodder units/ha, respectively. Depending on the level of soil fertilization, the content of the different phosphorus forms and fractions and potassium forms increased in all layers but to different extents.