Phytoremediation of Cd, Zn, Pb and Mn in leaf of nine trees species around the cement factory (phytoremediation of heavy metals in trees species)

Background and abjective: Cement factories are considered as one of the most important pollution sources, especially heavy metals pollution. At present, Phytoremediation is known as one of the best strategies to eliminate or reduce these pollutants. In the present study the phytoremediation ability of Cd, Zn, pb and Mn by nine trees species including Ailanthus glandulosa, Fraxinus rotundifolia, Robinia Pseudo Acasia, Ulmus umbraculifera, Eucalyptus microtheca, Quercus branti, Cupressus arizonica, Pinus eldarica and Cupressus sempervirens were investigated around the Ilam Cement Factory.
Material and For measuring the deposition of metals in the leaves of studied species, 0.2 grams of their biomasses were separately weighed then 4 ml nitric acid (65%) was added to each sample. After 24-hincubation at room temperature, the proportions of considered metals were determined by atomic absorption spectrometry.. The obtainedresults were analyzed by SPSS 20 software usingKolmogrov-Smirnov, Leven and One-way ANOVA Tests.
Results showed that the amount of Cd in electro filter of factory was approximately close to the amount of Cd deposited in leaves of considered species, however; the amounts of pb, zn and mn in electro filter of factory were much more than the amounts of these three metals in leaves. The maximum and minimum accumulation of pb were related to Eucalyptus microtheca and Cupressus sempervirens respectively. In addition, the maximum and minimum amounts of deposited Mn were in Ailanthus glandulosa and Pinus eldarica respectively. The results also indicated that the maximum and minimum accumulation of Zn were in Quercus branti and Fraxinus rotundifolia respectively.
It can be concluded from the results; the broad-leaf species are much more efficient than narrow-leaf ones in heavy metals remediation, so; it is suggested that in future development plans of green space, the broad-leaf species, especially Quercus branti, Ailanthus glandulosa Desf and Eucalyptus microtheca are more considered.