Parameters of biological circulation of phytomass and nutritional elements in crop rotations

Abstract

The research shows, that an increase of phytocoenoses provided an increase of phytomass volume in the biological cycle from 63.5 to 114.3 t/ha. The yield of phytomass in a crop rotation, different in structure and set of crops, was as follows: for four-field and five-field crop rotation - 63.5-86.7 t/ha, six field - 89.4, seven-field - 96.9, and eight-field - 114.3 t/ha. The optimization of the ratio of grain, technical and fodder crops allowed us to regulate quantitative parameters of crops’ phytomass, which was alienated from agrocoenosis. The yield of the main products, alienated from the field was, as follows: in four-field crop rotation -20.7 t/ha, five-field - 26.6, six-field -37.8, seven field -28.4 and eight field - 41.3 t/ha, which was 32.6%, 30.7%, 42.3%, 29.3% and 36.1%,respectively. The rest returned to the soil with by-products and crop remains. The total amount of nutrients (NPK) in the phytomass, involved in the circulation, was within the range for four-field crop rotation (100% of grain crops) – 1.814 kg/ha, five-field (80% grain and 20% technical) – 2.368 kg/hectare, six-field (66.8% of cereals, 33.2% of technical ones) - 2,599 kg/ha, seven-field (57.2% of cereals and 42.8% of technical) - 2.956 kg/ha, eight-field (62.5% of cereals, 25.0 % of technical, 12.5% of fodder) –3.491 kg/ha.