J. WIERZBOWSKA, S. SIENKIEWICZ, S. KRZEBIETKE and P. STERNIK
University of Warmia and Mazury in Olsztyn, Chair of Agricultural Chemistry and Environmental Protection, 10-719Olsztyn, Poland
WIERZBOWSKA, J., S. SIENKIEWICZ, S. KRZEBIETKE and P. STERNIK, 2016. Sewage sludge as a source of nitrogen and phosphorus for Virginia fanpetals. Bulg. J. Agric. Sci., 22: 722–727
By using sewage sludge for fertilization purposes it is possible to reduce amounts of mineral fertilizers used, to recycle biogenic substances in terrestrial ecosystems and to limit the costs of running plantations of energy crops. The objective of our study has been to assess the infl uence of sewage sludge on the content of macronutrients in Virginia fanpetals and the utilization of biogenic components from sewage sludge by the plants. Two forms of sewage sludge were tested: wet sludge dehydrated only by pressing and pelleted sludge. The content of dry matter, organic carbon, phosphorus, sodium, lead and nickel was higher in pelleted sludge. Wet sewage sludge had a more favourable effect on Virginia fanpetals’ yield than sewage pellets. The form of sewage sludge had negligible impact on the content of crude ash, although wet sewage sludge increased the concentrations of nitrogen, calcium, magnesium and sodium in biomass of Virginia fanpetals. The highest amounts of crude ash and macronutrients (except phosphorus) were comprised in plants fertilized with the highest dose of sewage sludge. The accumulation of these components in plants increased parallel to the increase in doses of supplied sewage sludge. Plants utilized nitrogen and phosphorus more effi ciently from wet sewage sludge than from its pelleted form.