EN
A vegetation experiment (88 days) studied the effect of soil contamination with fly ash produced in hard coal combustion (0.0; 33.3; 66.6; 99.9 g·kg-1 of soil) on the physicochemical properties of soil, the yield of oat (Borowiak) and maize (Reduta), selected soil bacteria count and the activity of soil enzymes: dehydrogenases, urease, alkaline and acid phosphatases. Oat was grown as the main crop and maize – as the successive crop. Two doses of nitrogen fertilisation were applied: 75 and 150 mg N·kg-1 of soil. Physicochemical, biochemical and microbiological analyses were conducted twice – after oat and maize harvest. A study of the ash-contaminated soil revealed an increase in the soil content of C, N, K, Mg, P, Ca, Na, Cu and Ni, the soil alkalisation, disturbed microbiological balance and reduced activity of dehydrogenases, urease and acidic phosphatase.