Cadmium and lead heavy metals phytoaccumulation in Imperata cylindrica as affected by the effects of soil organic matter and pH levels

Abstract

Nowadays, pollution of soils and consequent risks are major issues affecting humans and other organisms in the entire ecosystem. Imperata cylindrica grow fast and is of potential in phytoremediation. Imperata cylindrica was studied using different growth media of spiked heavy metal, soil pH and organic matter contents for 60-day. Imperata cylindrica was subjected to washing after harvesting, then roots and shoots were segregated. Sampled soils were digested with 1.0g portion of dried soil ,10.0cm3 of 1:1 HNO3: H2O, 5.0cm3 of HNO3, 1.0cm3 of H2O2, and 5.0cm3 of HCl while the plant samples were digested using 0.50g of the powdered sample, 5cm3 of HNO3 and 2cm3 HClO4. Before conducting the digestion, oven-dried at 70°C of each sample was ensured till a constant weight was reached, then grounded and milled (using a milling machine). Atomic absorption spectrophotometry instrument was utilized for analyzing the accumulation of Pb, and Cd content of shoot and roots. Proper translocation indices were used, and the highest total biomass of Cd was shown in 300g of organic matter treatment (13.48 ± 2.69 mg/kg), while Pb in basic treatment was 18.09 ± 0.66 mg/kg. The work divulge that, (regards to Imperata cylindrical phytoaccumulation) Pb is mostly affected by pH; while  Cd is mostly affected by organic matter in the phytoaccumulation. Growing of Imperata cylindrica for phytoremediation is important to control heavy pollution due to Pb and Cd.