CROP PRODUCTIVITY AND BALANCE COEFFICIENTS OF NUTRIENT UTILIZATION IN CROP ROTATION
On loamy soddy-podzolic soil in Vologda oblast, the calculated fertilizer systems provide a high productivity of crop rotation (5.2-5.6 t f.u./ha). The actual balance coefficients of nitrogen utilization were negative at the application of mineral and organic-mineral fertilizing systems at a dose of N93P41К90. The actual balance coefficients of potassium utilization at the application of calculated doses N93-138Р41К90 were 140-153%, which is close to the planned value. A near-zero balance was observed for phosphorus at the application of fertilizers at N93P41К90; the increase of nitrogen application rate up to 138 kg/ha resulted in a negative balance of the element, the intensity of which amounted to 85%.