Studies on the ecological succession of microorganisms during bioremediation of hyper-toxic crude oil polluted soil using five amendments

Abstract

Dangerous impact of crude oil in the environment is a common knowledge and its spillage has been controlled using both chemical and biological methods. Bioremediation however, is most advocated because of its environmental friendliness and sustainability. The present study sought to identify and monitor successions, and diversity of microorganisms elicited by five amendments in the bioremediation of hypertoxic crude oil pollution. Five amendment patterns which incorporated 200 g each of saw dust, wood chip, compost, N.P.K. fertilizer and poultry droppings; were used to stimulate biodegradation in 50% crude oil contaminated soil, and their respective microbial counts and microbial successions were monitored over a period of eight months. Statistical analyses were conducted using SPSS version 21 software. Poultry droppings amendment had the highest significant (p<0.05) bacterial and fungal counts. Bacillus subtilis, Stenotrophomas maltophilia and Pseudomonas aeruginosa were the predominant bacteria observed during the microbial succession studies across the amendment microcosms, while Aspergillus flavus, Penicillium citrinnum and Fusarium solani were the predominant fungal isolates. It was observed that the hyper-toxic concentration of the crude oil impacted the diversity and succession of the microbes across all the amendments used when compared to the control sample.