植物-降解菌群协同修复老化油污土壤OA

This study investigated aged petroleum-contaminated soil surrounding an oil well in Yanchang,northern Shaanxi Province.Indigenous high-efficiency petroleum-degrading bacteria were screened to construct a synthetic microbial consortium(MC-5).A controlled pot experiment was conducted to evaluate the individual and combined effects of phytoremediation,microbial remediation(MC-5),and plant-microbe synergism on total petroleum hydrocarbon(TPH)degradation and soil physicochemical property improvement.The roles of microorganisms and plants in co-remediation were systematically analyzed.The results showed that the microbial consortium MC-5(SDB1:SDB2:SDB3:SDB4=1:1:0:3)demonstrated optimal TPH degradation efficiency(83.46％).MC-5 combined with ryegrass achieved 60.93％TPH removal,representing a 54.26％increase over the control(CK).Notably,this treatment degraded 49.44％of recalcitrant resins and asphaltenes.Microbial degradation dominated TPH removal(contribution rate:63％～69％),significantly outperforming phytoremediation(2％～12％).Plant contributions became prominent only during later remediation stages.Rhamnolipid biosurfactant supplementation enhanced co-remediation efficacy,increasing TPH degradation by 7.05％compared to non-amended treatments.These results provide critical insights into the mechanisms of petroleum-contaminated soil remediation and establish a theoretical foundation for applying plant-microbe synergistic technology in oilfield soil restoration.The study offers practical guidance for optimizing bioremediation strategies targeting aged petroleum hydrocarbons.