ASSESSMENT OF NITROGEN POLLUTION OF THE ENVIRONMENT IN BULGARIA AND NUMERICAL SIMULATIONS FOR ITS MITIGATION.

Nitrogen pollution contributes to climate change, acid rain and eutrophication. The present study evaluates the degree of nitrogen contamination of air, surface and ground waters in Bulgaria with reference to the 2021 EU Action Plan 'Towards Zero Pollution for Air, Water and Soil' as well as the relevant international and national regulations in the field. The analysis uses data from the Bulgarian Ministry of Environment and Water, Ministry of Agriculture, the European Emission Database for Global Atmospheric Research - EDGAR, and FAO. The main sources of nitrogen pollution are considered with special attention to the mineral fertilizers applied to soils in agriculture. Numerical experiments implemented with the mathematical model WAVE identified rational fertilization rates, achieving permissible nitrogen pollution of the atmosphere and groundwater at good crop yields. The methodology can be applied for recommendation of good agricultural practices in order to preserve the ecological balance and optimize the economic costs of mineral fertilizers, especially in the current situation of their prices sharp increase. [ABSTRACT FROM AUTHOR]