Microbial community structure and metabolic characteristics of oil-contaminated soil in the Loess Plateau

Abstract

To investigate the impacts of crude oil pollution on the soil microbial community, and estimate the potential for crude oil degradation by indigenous microbial consortia, we examined the soil microbial community structure, metabolic characteristics and functional diversity of crude oil鄄contaminated soil collected in the Loess Plateau in northern Shaanxi, using plate counts and the Biolog Eco plate method. The results showed that the responses of soil microbes to crude oil pollution stress varied greatly. The abundance of bacteria and fungi in crude oil鄄contaminated soil were about one order of magnitude higher than in the uncontaminated soil, while the abundance of actinomycetes was significantly lower in polluted soil than in uncontaminated soil (P<0.01). The number of bacteria in crude oil鄄contaminated soil was 10 7 CFU / g, and the proportion of bacteria reached 99.8%-99.9% of all microbes. This indicated that majority of the crude oil biodegradation was the result of bacterial activity in collaboration with fungi rather than actinomycetes. The microbial activity of