Soil-ecological aspects of mineral fertilizers and NPK ratio­ning in soil

Abstract

Goal. To study soil and environmental aspects related to the rationing of mineral fertilizer application and control of the content of nutrients in the soil, taking into account modern land use conditions and guidelines and the experience of EU countries. Methods. Field — for field experiments with fertilizers; laboratory — to determine the content of mineral nitrogen in the soil; dialectical — to establish the suitability of the proposed methods for determining the norms of mineral fertilizers and tools for monitoring the content of nutrients in the soil; monographic — for gene­ralization of normative legal documents and scientific publications; abstract-logical — for theoretical generalization, formulation of proposals and conclusions; mathematical and statistical — for the analysis of the data obtained. Results. At the study sites, a direct correlation between the level of grain yield and the rate of mineral fertili­zer application was confirmed (r = 0.77 – 0.84). The factors for the determination of environmentally expedient norms of mineral fertilizer application are specified. The methodological issues on the use of MPC standards for hazardous substances in the soil (NO3, R2O5, and K2O), such as the normalization indicator and the method of its determination, differentiation of the distribution range of these MPCs, the layer of soil to which they apply, and the term for determining the NO3, are covered. The author’s scheme of soil-ecological approach to control the use of mineral fertilizers is presented. Conclusions. The algorithm for determining environmentally expedient rates of mineral fertilizers using the balance method is improved. A soil-ecological approach to control the use of mineral fertilizers and their impact on water objects and soils is proposed. The aspects of rationing and control of mineral fertilizers suitable for use throughout the country are presented.