Phytoremediation Capacity of Some Forage Plants Grown on a Metals-Contaminated Soil

ABSTRACT

Phytoremediation is a good strategy for metals-contaminated soils where the removal of contaminates is not a viable solution. Little is known about the quality of halophyte forage plants grown on metal-contaminated soils. A two-year field experiment was conducted to study the growth and elemental composition of three Atriplex species, maize and sorghum plants grown on metal-contaminated soil. Maize and sorghum plants significantly (P< 0.05)produced higher yields compared to Atriplex species. The fresh yield of the conventional forage plants and Atriplex species ranged between 3.4-3.6 and 1.1-1.4 tonnes ha⁻¹, respectively. Concentrations of Zn, Cu, Pb and Cd in maize and sorghum plants were significantly higher than those of Atriplex species. The nutritive value of the studied Atriplex plants was higher than that of maize and sorghum; moreover, the forage material of Atriplex species was safer. It was also observed that higher Zn, Cu, Cd and Pb content were accumulated in the roots than those of plant shoots; with low translocation factor (TF). The roots of Atriplex plants contained higher concentrations of SO₄, PO₄, Cl and oxalaterather than maize and sorghum plants. In metal-contaminated soils Atriplex plants are able to produce more safe forage materials than maize and sorghum.

KEYWORDS:

• Forage plants
• halophytes
• maize
• sorghum
• Atriplex