Evaluating tolerance of plants species to heavy metals in oil polluted region (Case study: Pazanan Gachsaran)

The purpose of this study was to investigate the tolerance of various plant species to heavy metals in oil polluted region of Pazanan Gachsaran. Three zones with various distances from highly polluted area were selected including 0 to 500 m, 500 to 1000 m and 1000 to 1500 m from pollution sources. Thirty plots of 2×2 were established in each transect and their vegetation characteristics were measured. Fifteen soil samples were collected and ICP- OES Instrument was used to measure Ni and Pb contents. Translocation Factor, Bio Concentration Factor and Biological Accumulation Coefficient indicators were used to evaluate the potential of 24 plant species from 12 families to absorb heavy metals. Results showed that the concentration of total and exchangeable soil Pb and Ni varied significantly between the various pollution zones. Xanthium spinosum L. ¡ Alhagi camelorum¡ Sinapis arvensis L.¡ Calotropis procera L.¡ Stipagrostis plumosa ¡Avena fatua L and Cynodon dactylon have Hyperaccumulator characteristics for Pb absorption Stipagrostis plumosa¡ Calotropis procera L.¡ Xanthium spinosum L.¡ Centaurea iberica¡ Sinapis arvensis L. ¡ Stipa capensis and Cynodon dactylon were identified as plant species with high accumulating potential for Ni. According to the results, some plant such as Stipagrostis plumosa¡ Calotropis procera L. and Sinapis arvensis L. have high potential for phytoremedation purposes and can be recommended in soil, contaminated soil containing Ni and Pb.