Biological Reclamation of Agricultural Soils Contaminated with Some Heavy Metals by Using the Currant Plant<i> hibiscus sabdariffa</i> L.

Bioremediation is used to reduce the effect of industrial and agricultural pollutants in contaminated soil, which in turn leads to removing and reducing the toxicity of heavy metals polluting the soil.This study evaluates the possibility of using the currant plant to reduce the concentration of heavy metals in some polluted soils within different locations in Babil Governorate.Soil samples were taken from four sites, representing agricultural soil irrigated with wastewater, soil adjacent to a brick factory, and soil adjacent to a sterile drinking water factory, in addition to a control sample, which is agricultural soil irrigated with river water.The soil samples were analyzed Soil to determine the general characteristics and concentration of the total heavy elements represented by lead (Pb), cobalt (Co), nickel (Ni) and zinc (Zn).Then the pollution standards for the soil and plants were calculated and the averages were compared using the least significant difference test at the 5% level.The results showed that nickel and Zinc were significantly superior to the total content of elements in the soil, and the lowest values were for Cobalt.The values of the contamination factor for the soil showed that nickel was in first place, followed by Cobalt, then Lead and Zinc.As for the pollution load index (PLI), its value was highest in the agricultural soils adjacent to the bricks factory, while the values of the accumulation index (I geo ) indicated that the Nickel element had surpassed on Cobalt, Zinc and lead.The concentration of elements in the plant shoots indicated a superiority in Zinc and Cobalt, while Nickel and Lead were superior in the root system.The BCF index was less than one for all sites except agricultural soils irrigated with river water, and the site transfer factor TF values were greater than 1 In the elements Cobalt and Zinc.The results also showed that the currant plant is one of the plants that accumulates the heavy metals because it does not show negative symptoms during its growth and thus the possibility of using it to reduce the risk of heavy elements in the soil.