EFFECTS OF ORGANIC AMENDMENTS ASSISTED PHYTOREMEDIATION POTENTIAL OF LEAD CONTAMINATED SOIL BY MAIZE

Abstract

Phytoremediation, the use of plants and their associated microbes for environmental cleanup, has gained acceptance in the past 10 years as a cost-effective, noninvasive alternative or complementary technology for engineering-based remediation methods. Plants can be used for pollutant stabilization, extraction, degradation, or volatilization. This study evaluated the effects of organic amendments to enhance phytoextraction of heavy metal lead (Pb) from artificially polluted soil by maize (Zea mays). The objective of this study was to investigate the impacts of altered soil chemical properties (soil pH, OM, cation exchange capacity, electrical conductivity, base cation (Ca, Mg, K and Na) on phytoremediation of Pb contaminated soil due to application of compost, biochar, ash, poultry litter and co-compost. The treatments were a) control with 200mg Pb, b) Pb contaminated soil with compost 100g (10%), c) Pb contaminated soil with ash 100g(10%), d) Pb contaminated soil with biochar 100g (10%), e) Pb contaminated soil with poultry litter 100g (10%), f) Pb contaminated soil with co-compost (10%) and replicate three times in a completely randomized design. The results indicated thatthe compost, poultry litter significantly enhanced the growth ratio and plant heightof maize under Pb contaminated environment. Ash and biochar increased plant height same as control. Biochar and COMBI increased total amount of plant available P and N. Compost, ash, poultry litter showed the same effect on total phosphorus and nitrogen which was greater than the control. In case of soil pH, the sequence is: poultry litter> COMBI> compost> biochar>ash>control. For soil OM: compost>COMBI> biochar> control> poultry litter>ash. For soil EC: compost>poultry litter>COMBI>ash> biochar>control and soil CEC: compost>poultry litter>COMBI>biochar>ash>control. Moreover, compost enhanced base cations like Ca, Mg greater than ash, biochar, poultry litter, co-compost. Poultry litter accelerated base cations like K, Na compared to control. Therefore, it can be suggested that application of organic amendments like biochar, compost, ash, poultry litter, co-compost was the most suitable choice for the treatment of Pb contaminated soil phytoremediation.