Decontamination of Agricultural Soil Polluted with Lead using the Common Barley (Hordium vulgare)

The present work aimed at studying the possibility of decontaminating polluted soil by lead from traffic road, using Hordeum vulgare as a heavy metals hyper accumulative plant. High concentrations of lead stored at the horizons of soil surface (1714.39 ± 512.62 μg g-1), have revealed that the traffic and road infrastructures are important outcomes of toxic heavy metals to the environment. In addition, we noticed that Hordeum vulgare may hold a total of 36.28 ± 14.90 μg g-1, which correspond to 2% of that to of that accumulated in the soil. Importantly, highest values were observed in the roots (18.32 ± 8.38 μg g-1), which means 50,50%, whereas, the rate of heavy metals in the stems and leaves were 10.83 ± 5.86 μg g-1 (29,95%) and 7.71±3.74 μg g-1 (21,25%), respectively. Otherwise, the accumulation of lead was influenced by physical and chemical properties of the soil (pH, cation-exchange capacity CEC, percentage of clay). A high content of lead was observed in the plant at low pH; in contrast, the CEC of the soil and the percentage of clay, positively correlated with plant Pb. However, a strong correlation between soil Pb and plant Pb was noticed. Accordingly, lead uptake by Hordeum vulgare seems to be influenced by its bioavailability in soil.