The objective of our study was to assess the residual effect of sewage sludge on the growth and yield of Prairie cordgrass and the content of crude ash, macroelements and heavy metals in the plant biomass. Field trials conducted in the years 2011 to 2013 focused on the assessment of the impact of municipal sewage sludge applied from 2008 to 2010on the growth and yield of Prairie cordgrass. The experiments followed the split-plot design with two variables: the rate of sewage sludge (DM-dry matter) at 0, 1.4, 2.8 and 4.2 t ha-1, corresponding to nitrogen fertilization with: 0, 50, 100, 150 kg ha-1, and the harvest time - fall and winter. The total dose of sewage sludge applied in 2008−2010 was 0, 4.2, 8.4 and 12.6 t DM ha-1, which corresponded to the total dose of nitrogen fertilization: 0, 150, 300 and 450 kg ha-1, respectively. The municipal sewage sludge at a rate of 8.4 t DM ha-1, compared to the Control, significantly increased the number of leaves per plant, the leaf and culm matter, the number of shoots per 1 m2, the dry matter yield, crude ash deposition and uptake of macroelements and heavy metals.
Financed by the National Centre for Research and Development under grant No. SP/I/1/77065/10 by the strategic scientific research and experimental development program:
SYNAT - “Interdisciplinary System for Interactive Scientific and Scientific-Technical Information”.