Plants Growth on Different Fertilized Agricultural Land and Metal Bioavailability

The study compares the amounts of Zea mays, grains, cobs and stalks, harvested on fertilized / unfertilized variant with different fertilizers: M-control, V 1 -fertilized with sewage sludge 50 t/ha + indigenous volcanic tuff, 5 t/ha, V 2 -fertilized with sewage sludge 50 t/ha, V 3 -fertilized with cattle manure, 50 t/ha. The amount of grains and cobs harvested from variant fertilized with cattle manure or sewage sludge mixed with indigenous volcanic tuff were similar. The amount of cobs and grains harvests from variant fertilized with sewage sludge mixed with indigenous volcanic tuff were higher between 15.1-17.5%, respectively 15.4-19.1% than those harvested from variant fertilized with sewage sludge. The indigenous volcanic tuff used as addition at sewage sludge was an important factor for the reduction of bioavailability of metals in the aerial tissues of the plant. The amount of toxic metals, Cd, Cr, Ni, Pb and Zn from the tissues of Zea mays plants was below the maximum limits allowed by the UE rules.