Investigation of the Potential of Gundelia Tournefortii as a Sorbent of Heavy Metals in Contaminated Soils

It is very important to study the concentration of heavy metals in plant species grown in agricultural soils because of the possibility of heavy metals accumulation. Gundelia tournefortii is one of the edible species used in different parts of the country that has the potential for growth in agricultural lands. In addition, the using of plants with high accumulation ability is one of the most effective methods for clearing up the soils contaminated with heavy metals. Accordingly, the present study examined the potential of Gundelia tournefortii as a heavy metal adsorbent in agricultural and non-agricultural lands. For this purpose, 4 stations in agricultural areas and 2 stations in non-agricultural areas (control) were selected. At each of these stations, three plant samples were completely removed from the root and surrounding soil were also collected. After preparation and digestion of samples, the concentrations of heavy metals such as chromium, nickel, zinc, copper, manganese and iron were determined using atomic absorption spectrophotometer. For each plant, bioconcentration and transfer factors were calculated. According to the results, Gundelia tournefortii is recognized as hyper accumulator for zinc, manganese, copper, and nickel and medium accumulator for chromium and iron. Also the findings showed significant differences between heavy metals concentrations in the agricultural and non agricultural areas for soil, shoot and root biomass (p <0.05). Therefore, the consumption of plants grown in agricultural lands is more risky due to the higher concentrations of heavy metals. Considering the accumulation of heavy metals based on the transfer and accumulation factors in this species, it can be proposed to remediate heavy metals contaminated areas.