| Abstract [eng] |
Phosphorus is one of the 6 major trace elements involved in various life support processes, a finite earth resource that cannot be replaced by other elements or compounds. For the purpose of efficient use and recovery of this element, the Mass and Mass Analysis method, which examines flows, aggregations and losses at global, regional and national levels, is used. The Baltic States have not carried out phosphorus flow and mass analysis, therefore, this research will seek, through research conducted by other countries to develop a conceptual model of Lithuania's major phosphorus flows, which will provide an opportunity to analyze in more detail the main domestic phosphorus movements in fertilizer, agricultural and waste subsystems. By designing a phosphorus flow and balance model with the STAN software, to identify the main sources of phosphorus loss, and to propose measures to apply secondary phosphorus. The study found that 204 116 tons of phosphorus/year are imported to Lithuania, mainly in natural calcium phosphates – 82,3 %, in food and feed 9 %, in fertilizers 8,7 %, and exported in 1970099 t P/year - 80.3% fertilizers and 17,3 % in food and feed. Compared to other countries, it is estimated that Lithuania consumes 1.86 times more P-weight than the EU–27 weight and flow, and consumes a relatively large amount of mineral fertilizers compared to organic – 24 % more than the EU–27 average. The balance of phosphorus imported and exported by Lithuania in food and feed is negative -5,65 kg / capita per year, thus reducing the amount of possible recovery of secondary phosphorus, while the balance of 27 European Union states is positive +1,88 kg/capital. In order to achieve a circular and sustainable model of phosphorus management, the main identified opportunities for Lithuania are the production of good quality sewage sludge that could be used as fertilizer or compost. Control of the formation and insertion of manure and slurry into the soil, avoiding excessively fertilized soils on livestock farms. Collection of biodegradable waste and used to produce compost. |
