effect of barley and oat plants on phytoremediation of petroleum polluted soils

Total petroleum hydrocarbons (tphs) are one of the most dangerous organic contaminants in the environment. therefore, the remediation of the oil-contaminated soil is necessary. the growth of barley and oat plant was studied in the contaminated soils (4, 6, 8% tphs) during 5 months. plant height, wet and dry weight of shoots and roots of both plants were measured. results showed that oat and barley height, wet and dry weight of shoots and roots decreased with increasing contamination levels. regardless of the plants species, the highest rate of tph reduction was observed in soil with 4% contamination and decreased with increasing the contamination level. the tphs concentration in the rhizosphere of barley and oat decreased by 29.66 and 24.04% at the 6% tphs level and by 21.24 and 17.48% at the 8% tphs level, respectively. cultivation of barley and oat plants significantly accelerated the biodegradation of hydrocarbons and reduced tphs content in soil as compared to unplanted soil.