Justification of the resource-saving system of arable farming when providing inter-sectoral optimization of reclamated agro-ecosystems of Polissya

Goal. To highlight the peculiarities of the formation of the cycle of organic carbon, nitrogen, phosphorus and potassium in different branch structures of agrarian production and to substantiate of the resource-saving organic farming system, which will ensure reproduction of the fertility of drained sod-podzolic soils. Formation of multisectoral agrarian production allows to achieve a high level of recirculation of biogenic elements, significantly reduce compensatory doses of mineral fertilizers and ensure of no-deficit organic carbon balance. In order to carry an accurate quantitative assessment of these opportunities concerning of diverse agroecosystems in the conditions of the Right Bank Polissya, the research task was to evaluate the cycle of nutrients in different scenarios of the development of a typical agricultural production. Methods. Stationary agrotechnical experiments, simulation computer modeling, economic analysis. Results. Based on the results obtained in the experiments, the following prospective Models LLC «Ukrainian Food Alliance» with the area of ​​arable land of 2850.5 hectares, were considered: №1 « Plants specialization», №2 «Livestock specialization», № 3 «№ 2 + processing and storage », № 4 «№ 3 + biogas equipment», № 5 «Model № 4 + drainage-humidifying system», № 6 «№ 5 + flax», № 7 «№ 6 + 7 thousand hectare of arable» — extension of arable land to 10 thousand hectares to ensure full loading of flax processing equipment. It is established that of all proposed scenarios of the development of the enterprise only under the conditions of Model № 1 with grain specialization and alienation from the field of all crop production will be formed acutely deficient balance of humus. For the implementation of other variants of the sectoral structure, systematic increase of organic material stocks in the arable layer of soil, will be ensured. Only under the conditions of Model № 1 due to the cultivation of only grain crops and flax is formed a negative balance of nitrogen, therefore it is necessary to add nitrogen fertilizers in the amount of 65 kg per hectare. According to the scenarios of other Models of nitrogen fertilizers there is no need to apply with 40-90 kg per hectare of phosphorus and 70-100 kg per hectare of potassium. That is, the development of livestock husbandry makes it possible to significantly increase the level of recirculation of nutrients. At the same time, one of the main tasks is the development and implementation of an efficient system of production, storage and introduction of organic fertilizers. This situation allows us to move on to the principles of organic farming with the profitability of agrarian production of $ 4-8 thousand per hectar. Conclusions. Conducted balance studies and highlighted technological aspects of the use of organic fertilizers in the melioration land of the humid zone indicate that the implementation in practice of one of the proposed perspective scenarios of development of enterprise actually refers to the development of bioorganic farming system with a minimum of use of agrochemicals. These aspects are the main factors and preconditions for the high competitiveness of melioration agro-ecosystems of Polissya in the future with the achievement of net profit at the level of $ 8 thousand per hectare.