The Characteristics Of Bacterial Community In Response To Oil Pollution And Copper Pollution In Jiaozhou Bay Sediment

Jiaozhou bay is a typical semi-closed and shallow bay. It has been greatlyinfluenced by anthropogenic activities in its surrounding. With the development ofindustry, oil pollution and heavy metal pollution have become more serious andinfluenced the sustainable development of marine ecosystem therefore it attractedmore attentions. According to the survey data of Jiaozhou bay area, this paperchooses petroleum hydrocarbon and copper for represent.The present researchthoroughly discussed the influence of the microbial community structure and functionon sediment, and revealed the response of the microbial communitycharacteristics.And then provided theoretical foundation and data support toenvironmental impact assessment and ecological restoration about petrol and copperpollution.This experiment used the dynamic microcosm model simulated seabedenvironment to research the influence of petroleum hydrocarbon on bacteria diversityand community structure in sediment. The results suggested that, in all treatments, thetotal number of bacteria changed consistently which quickly declined from theoriginal1.08×10⁹cells·g^-1to a basically stable number5.4×10⁸cells·g^-1.Dehydrogenase activity was gradually enhanced after adding1000mg·L^-1petroleumto the sediments and up to3.3×10⁴μgTPF·g^-1within15days. And the number ofpetroleum-degrading microorganisms increased obviously, up to1.5×10⁵cell·g^-1.Theplating count showed that dosing phosphorus element had strengthened heterotrophicbacteria, which increased its amount significantly. DGGE profiles indicated thatdosing petroleum had caused community structure to change. Deltaproeobacteria weredominant, the ratio was84.6%. This study demonstrated that the microbialcommunity structure and function in sediments were affected greatly after dosing petroleum.. Phosphorus element made heterotrophic bacteria multiply but there wasno significant influence on petroleum degrading function.To explore the possible impact of heavy metal input on ecosystem of marinesediments, microcosm model was applied. This paper also discussed the response ofcopper to microbial community structure and function. Analysis of gene sequenceindicated that the quantity of Deltaproteobacteria, Chloroflexi and Acidobacteria werehigher in control than that in copper contaminated sediments, especially, Chloroflexiwhich was as much as two times. While Alphaproteobacteria andGammaproteobacteria were lower in control compared with those in copper pollutedsediments.It was found that microbial community of the control and copper wasdifferent; on the contrary, there were no obvious effects on Ammonia oxidizingbacteria community. Microbial community and function showed significant responseto copper processing compared with community structure and composition. Theability of utilizing carbon source and the functional diversity decreased after coppertreatment, while the quantity of cultivable heterotrophic bacteria was10%of control.The results demonstrated that increasing Cu²⁺concentration in sediments inhibited thenumbers of cultivable bacteria and damaged the community function.