Response Characteristics between Sulfate-Reducing Bacteria and Environmental Factors in Petroleum Hydrocarbon-Contaminated Field of Northeast China

Lithology samples were collected from six sites of a petroleum hydrocarbon-contaminated site in northeast China along a contamination plume. The sulfate-reducing bacteria (SRB) diversity of all samples was analyzed by PCR-DGGE technology. The Shannon-Wiener indexes (1.004–3.665), Simpson indexes (0.516–0.907) and Pielou indexes (0.996–1.004) of all samples were used to characterize the abundances, advantages and evenness of the microbial communities. Additionally, Canoco for Windows 4.5 was utilized to analyze the correlation between dominant SRB and environmental factors. The results showed that the abundance, advantages and evenness of the sulfate-reducing bacterial community changed regularly along the contamination plume direction. The microbial homology of the samples was not high (0.25–0.80), and the dominant bacteria exhibited heteroplasmy. Additionally, the dominant bacteria were identified as uncultured bacteria. Canonical correspondence analysis (CCA) analysis showed that the distribution and structure of SRB communities were not obviously correlated with the concentration of total petroleum hydrocarbons (TPH), dissolved oxygen (DO) and other environmental factors. The results presented herein provide evidence of natural bioremediation in petroleum hydrocarbon-contaminated fields and information that will be useful to bioremediation of other contaminated fields.