Evaluation of the Efficiency of Nerium oleander in the Phytoremediation of Lead Pollution by using Humic Acid

Abstract

A field experiment was conducted in the lath house of the Agricultural Research and Experiment Station of the College of Agriculture in the governorate of Kirkuk-Iraq for the period from 1/3/2022 to 1/9/2002, to evaluate the efficiency of N.Oleander L.Album Plenum in the phytoremediation of lead (Pb) contaminated soil by adding Humic acid with three levels (0,5,10) ml..pot−1 of soil directly, the design of the experiment used is R.C.B.D. The results of the mechanisms and indicators of the efficiency of the nerium oleander in the extraction of heavy metals showed that the oleander plant with the assistance of humic acid has a high ability to absorb and accumulate the lead element very effectively, and the concentration of 10 ml.pot−1 of humic increasing the concentration of the Pb in the shoot and root system (30.71, 16.83 PPM) respectively, however the concentration of lead in the control plants was (25.32 and 14.36 PPM) respectively. Translocation factor TF>1 for all humic concentrations (1.82, 1.88, 1.77), respectively, and this indicates the high ability of the oleander to absorb and accumulate heavy elements. The concentration of 10 ml.pot−1 of humic acid gave the highest value of the bioaccumulation factor (BAF) 0.85, however it was 0.64 in the control plant. The concentration of 10 ml.pot−1 of humic was also superior in giving the highest value of the concentration index (CI), which ranged 1.27, and 1.06 in the control plant.