Hydrocarbon-Degrading Bacteria and Paraffin from Polluted Seashores 9 Years after the Nakhodka Oil Spill in the Sea of Japan

Pollution of petroleum hydrocarbons, in particular oil spills, has attracted much attention in the past and recent decades. Oil spills influence natural microbial community, and physical and chemical properties of the affected sites. The biodegradation of hydrocarbons by microorganisms is one of the primary ways by which oil spill is eliminated from contaminated sites. One such spill was that of the Russian tanker the Nakhodka that spilled heavy oil into the Sea of Japan on January 2, 1997. The impact of the Nakhodka oil spill resulted in a viscous sticky fluid fouling the shores and affected natural ecosystems. This paper describes the weathering of hydrocarbon-degrading bacteria （genus Pseudomonas） and crystallized organic compounds from the Nakhodka oil spill-polluted seashores after nine years. The Nakhodka oil has hardened and formed crust of crystalline paraffin wax as shown by XRD analysis （0.422, 0.377, and 0.250 nm d-spacing） in association with graphite and calcite after 9 years of bioremediation. Anaerobic reverse side of the oil crust contained numerous coccus typed bacteria associated with halite. The finding of hydrocarbon-degrading bacteria and paraffin wax in the oil crust may have a significant effect on the weathering processes of the Nakhodka oil spill during the 9- year bioremediation.

Oil pollution experiment in marine-enclosed experimental ecosystem Ⅰ. Ecological distribution of hydrocarbon-degradation bacteria

On the basis of the investigation into ecological distribution degradation and the self-purification ability of hydrocarbons by microbes, this paper deals with the study of ecological distribution of hydrocarbon-degrading bacteria and its correlation with environmental factors in a marine-enclosed experimental ecosystem in the eastern part of the Xiamen Bay.

The effects of electrical heating and additives on the microbial remediation of petroleum-contaminated soils

Although petroleum is an important source of energy and an economic driver of growth,it is also a major soil pollutant that has destroyed large swathes of vegetation and forest cover.Therefore,it is vital to develop affordable and efficient methods for the bioremediation of petroleum-contaminated forest soils to restore vegetation and improve tree survival rates.In this study,bioremediation experiments were performed in an electrically heated thermostatic reactor to test the effects of organic matter additives,surfactants,and oxygen providers of nine hydrocarbon-degrading fungal strains on crude oil removal rates.In the three soil temperatures tested(20℃,25℃,and 30℃),the highest average crude oil removal rate was at 25℃(74.8%)and the lowest at 30℃(49.4%).At each temperature,variations in the addition of organic matter and oxygen providers had significant effects on crude oil removal rate.Variations in surfactant addition was significant at 20℃ and 25℃ but insignificant at 30℃.Given the same surfactant treatment,variations in temperature,organic additives,and oxygen providers was significant for crude oil removal rate.Treatments without surfactants and treatments with Tween80 exhibited their highest crude oil removal rates at 25℃.However,treatments that included the SDS surfactant exhibited their highest crude oil removal rates at 30℃.Amongst the treatments without surfactants,treatments with corn cob addition had the highest crude oil removal rates,and with surfactants,treatments that included the organic fertilizer exhibited the highest crude oil removal rates.Given the same organic fertilizer treatment,the highest crude oil removal rate was at 25℃.At each level of oxygen availability,the maximum crude oil removal rate always occurred at 25℃,and the treatments that included organic fertilizer exhibited the highest crude oil removal rates.Amongst the treatments without oxygen providers,treatments without surfactants had the highest crude oil removal rates,and with an oxygen provider,treatments with SDS addition exhibited the highest crude oil removal rates.Based on the crude oil removal rates of the treatments,we determined that S_(1)W_(1)O_(1)(addition of Tween80,organic fertilizers,and H_(2)O_(2))was optimum for remediating petroleum-contaminated forest soils in cold,high-altitude regions.This study is helpful to vegetation restoration and reforestation on petroleum contaminated forestlands.