This study investigated the transport and accumulation of several heavy metals within the lower and upper parts of the wild plants Typha domingensis, Prosopis farcta, and Alhagi maurorum, belonging to the Al-Kasak and Al-Qayyarah sites in Iraq, which were collected in autumn. In the Al-Kasak refinery, results indicated the cadmium (Cd) and nickel (Ni) showed significantly higher bioaccumulation in the root system (392.01 and 658.11 mg/kg, respectively) from dry weight compared with the dry weight of shoots (287.12 and 619.45 mg/kg, respectively). However, the lead (Pb) and manganese (Mn) exhibited higher bioaccumulation in the shoot system (280.23 and 80.95 mg/kg dry weight, respectively). At the Al-Qayyarah refinery, Ni, Pb, and Mn appeared more accumulated in root parts (668.65, 270.61, and 156.24 mg/kg dry weight, respectively) than in the shoots for each plant (Prosopis farcta, Alhagi maurorum, and Typha domingensis). Meanwhile, Cd bioaccumulation was higher in the shoots (377.31 mg/kg dry weight). Additionally, the roots of Alhagi maurorum and Typha domingensis revealed higher accumulations of Ni and Mn (778.25 and 235.93 mg/kg dry weight, respectively) compared with the shoot system. At the Al-Kasak site, plants showed a higher bioaccumulation of Pb (13.38 mg/kg dry weight), following the order Pb<Ni<Mn11.14>3.93>1.44 dry weight, respectively). Then again, plants at the Al-Qayyarah site had the highest bioaccumulation of Ni (17.94 mg/kg), with the order of bioaccumulation as Ni>Mn>Pb>Cd (17.94>11.75>3.84>1.07 mg/kg dry weight, respectively). The maximum bioaccumulation of Mn was notable in the plants of Typha domingensis, Prosopis farcta, and Alhagi maurorum (28.86, 146.68, and 419.86 mg/kg dry weight, respectively).

Keywords: Wild plants, heavy metals, phytoremediation, bioaccumulation, biotranslocation

Key findings: At the Al-Kasak site in Iraq, the bioaccumulation of Ni, Cd, and Pb was higher in roots than in shoots, while the bioaccumulation of Pb and Mn was higher in shoots of wild plants. However, at the Al-Qayyarah site, the bioaccumulation of Ni, Pb, and Mn was greater in roots, while the bioaccumulation of Ni was superior in shoots of wild plants.