Impact of human activities on microbial community structure in coastal sediments after Hebei Spirit Oil Spill Accident

Abstract

Korea had been experience severe oil spill accident in Dec. 2007 by M/V Hebei Spirit. At that time approx. 10,800 tons of oil was spilled into marine environments over wide range of coastal areas. The accident caused severe damages on coastal ecosystem and consequent deep socio-economical impacts. The community structure of microorganisms changed respond to environmental event very sensitively, and hence, could be used as a short term indicator of oil impact on coastal area. The monthly changes of bacterial community structure for one year after spill was analyzed by pyrosequncing method and Ez-taxon-e database at two different spill impacted coastal sediments (Gureumpo and Mallipo). In phylum level, members of the Proteobacteria and Bacteroidetes were always dominated but showed seasonal difference between two phyla. Members of the genus Psychrobacter was predominant in two winter seasons at Gureumpo where the remediation activities implied later than other areas. In case of Mallipo, where the extensive remediation activity had been conducted, members of the genus Psychrobacter dominated only in end of the year 2008. The hydrocarbonoclastic microorganisms such as the members of genus Cycloclasticus were dominant during winter to spring in polluted areas especially in Gureumpo. After than proportion of microorganisms known to be aromatic hydrocarbon degraders such as Sphingomonad were increased in summer season. Suddal ecosystem and consequent deep socio-economical impacts. The community structure of microorganisms changed respond to environmental event very sensitively, and hence, could be used as a short term indicator of oil impact on coastal area. The monthly changes of bacterial community structure for one year after spill was analyzed by pyrosequncing method and Ez-taxon-e database at two different spill impacted coastal sediments (Gureumpo and Mallipo). In phylum level, members of the Proteobacteria and Bacteroidetes were always dominated but showed seasonal difference between two phyla. Members of the genus Psychrobacter was predominant in two winter seasons at Gureumpo where the remediation activities implied later than other areas. In case of Mallipo, where the extensive remediation activity had been conducted, members of the genus Psychrobacter dominated only in end of the year 2008. The hydrocarbonoclastic microorganisms such as the members of genus Cycloclasticus were dominant during winter to spring in polluted areas especially in Gureumpo. After than proportion of microorganisms known to be aromatic hydrocarbon degraders such as Sphingomonad were increased in summer season. Sudd