Content of heavy metals in maize cultivated in soil amended with sewage sludge and its mixtures with peat

The experiment was aimed at an assessment of the effect of sewage sludge and its mixtures with peat on the content and uptake of chromium, copper, lead and nickel by maize cultivated in soils of different grain size composition. The concentrations of studied elements were assessed after plant material mineralization using the ICP-AES method. Fertilization with the sewage sludge, its mixtures with peat and with farmyard manure allowed to obtain significantly larger yields than on treatments fertilized exclusively with mineral salts. The experiment results indicate that the soil had a greater effect on trace element concentrations than the applied fertilization. Mean weighted average content of the analyzed elements in maize aboveground parts from the treatments where sewage sludge mixtures with peat were applied was generally smaller in comparison with the content determined in biomass from the treatments where only the sludge was used.