enhanced bioremediation of field agricultural soils contaminated with pahs and ocps

effect of different concentrations of ammonium chloride (ncl) and ammonium nitrate (nn)and surfactants such as tween-80, hpcd and rhamnolipids on the bioremediation of pahs and ocps wasinvestigated. the results showed that the best optimum concentration of ncl and nn was 50 g·kg-1, and thepahs degradation rate during 60 days of remediation was enhanced to 64.6% and 62.8% for ncl and nn,respectively, which was approximately 45, 17, 10% higher than those in the control group, soil only addedmicroorganism, soil added microorganism and tourmaline. ocp removal rates were 51.7% and 50.4 % for ncland nn, respectively, which was 34% higher than the control group, 14% higher than the soil only addedmicroorganism, 9% higher than the soil added microorganism and tourmaline. the best dose of tween-80,hpcd and rhamnolipids was 2, 0.5 and 0.2 g·kg-1. when they were applied, the pahs degradation rate during60 days of remediation was enhanced to 69, 70.4 and 71.5%, respectively, which was approximately 52, 24and 17% than those in the control group, soil only added microorganism, soil added microorganism andtourmaline. similarly, ocp removal rate was 42, 26 and 16% higher than those in the control group,microorganism -added soil alone, soil added microorganism and tourmaline. additionally, nutrients and surfactantscan promote the generation of soil hydrogen peroxidase and invertase enzyme. hence, the present studyprovides a promising combination remediation technology for the remediation of field soils contaminated bypahs and ocps.