Influence of fertilizers and cultivation on the quality of soddy podzolic soil and productivity of field crop rotations in conditions of Zhytomyr Polissia

Abstract

Goal. To make a comparative assessment of the productivity of different variants of long-term application of the fertilizer system in 9-field crop rotation and cultivation of radioactively contaminated soddy podzolic soil concerning its agroecological condition and impact on the productivity of field crops. To develop the measures to minimize the content of 137Cs in crop products. Methods. Field, laboratory-analytical, mathematical-statistical. Results. The influence is studied of long-term systematic application of fertilizers in crop rotation, as well as variants of basic tillage of soddy podzolic soil on humus condition, its physicochemical and agrochemical properties. It is determined that long-term use of organic fertilizer system on the background of flat cultivation of soil (20–22 cm) provides the positive balance of humus reserves at the level of 9.8 t/ha. Planar tillage (20–22 cm) using organic and organomineral fertilizer systems helped to reduce the specific activity of 137Cs by 42.6–43.9% compared to fallow (296 Bq/kg). It is proved that field crops under the growth of the ability to accumulate 137Cs are placed in the following sequence: lupine (seeds) > corn (green mass) > winter wheat and spring barley. Conclusions. It is established that the organomineral fertilizer system (7.8 tons of manure + N57R63K75 per 1 ha of crop rotation area for one rotation of 9-field crop rotation) for plowing the soil to the depth of 20–22 cm for row crops and 18–20 cm for continuous sowing provides the highest yield of fodder units (4.6 t) per 1 ha of crop rotation area per rotation. Crop yields, excluding lupine grains, obtained during cultivation on radioactively contaminated soddy podzolic soil (<290 Bq/kg 137Cs) in terms of the specific activity of this radionuclide had significantly lower values which were stated in the State Hygienic Standards “Permissible levels of 137Cs and 90Sr radionuclides in food and drinking water” (DR-2006).