Remediation of Petroleum-Contaminated Saline-Alkali Soil by a Combination of Leaching and Fertilization

A method was developed to remediate petroleum-contaminated saline-alkali soil using a combination of leaching and fertilization. The degradation efficiency of oil and grease was (19.7±4.3)% higher in soil treated by leaching combined with fertilization than that in control soil, and was (13.8±3.4)% higher than that in soil treated by fertilization. In addition, the removal efficiency of salinity was (66.5±2.9)% higher in soil treated by the combination of leaching and fertilization than that in control soil, and was (41.3±6.2)% higher than that in soil treated by fertilization. The results suggested that the treatment of leaching combined with fertilization might be an efficient method for the remediation of petroleum-contaminated saline-alkali soil. The number of heterotrophic bacteria, petroleum hydrocarbon degraders, alkane degraders and polycyclic aromatic hydrocarbons(PAHs) degraders and soil microbial activity increased significantly in the treatment of leaching combined with fertilization, further suggesting the microbial degradation of oil and grease was enhanced. Shannon index and Simpson index of the microbial community also increased markedly in such treatment, implying the microbial community was in recovery.