Effect of granular fertilisers produced from industrial and municipal wastes on the crop yield and their content of macroelements

Four granular fertilisers were produced from industrial waste products, such as CaSO₄ 2H₂O and FeSO₄ 7H₂O, coniferous and deciduous sawdust mixture and municipal sewage sludge with addition of mineral fertilisers. Based on the content of organic matter, nitrogen, phosphorus and potassium and heavy metals, these granular fertilisers can be included into the group of organic-mineral fertilisers. In order to determine their manurial value, a vegetation experiment was carried out with these granular fertilisers in which spring rape and spring triticale were the test plants. The study results show that granular fertilisers increased signifi cantly the yields of test plants and their content of macroelements. The granular fertilisers containing FeSO₄ 7H₂O increased signifi cantly the yields of test plants and the contents of macroelements when compared to those with CaSO₄ 2H₂O. As affected by the granular fertilisers containing CaSO₄ 2H₂O, there was more phosphorus, calcium and sulphur in the test plants. The granular fertilisers composed of the waste products mentioned above can be a cheap source of organic matter and nutrients for plants and may reduce possibility of environmental contamination.