Movimento de zinco em colunas de solo tratado com resíduo calcário oriundo de mineração

Zinc movement through columns of soil ammended with limestone mining residues The vertical movement of contaminants through soils is a problem of great environmental impact on human society. The growing use of urban and industrial residues contaminated with heavy metals in agriculture has been drawing attention to this issue, particularly to the mobility of these elements. Therefore, the objective of this work was to analyze the movement of Zn in soil columns and to verify the effect of water-soluble plant extracts on such movement. The experiment was carried out in a greenhouse. Brachiaria grass (Brachiaria decumbens Stapf) and maize (Zea mays L.) extracts were prepared and poured in PVC columns containing a very clayey typical dystroferric Red Latosol (Rhodic Hapludox), previously amended with naturally Zn-rich limestone residue (LR) . Irrigation was performed by adding distillated water or plant extracts into the columns for seven days. The results showed no movement of Zn in the studied period, since these metals remained in the soil. Plant extracts did not significantly modify the results. It is likely that the studied LR has low available Zn. Thus, a single application of LR will hardly lead to any environmental problems and the risk of groundwater contamination is very low.