The Community Structure And Functional Characteristics Of Sulfate-reducing Bacteria In Jiaozhou Bay Aquaculture District

China is a big maricultural country. High density and intensive farming patternhave caused the aquaculture water degradation, which not only leaded to thedestruction of the ecological environment of the aquaculture water but also broughtserious environmental pollution and eutrophication to the coastal waters.Sulfate-reducing bacteria has the capacity of restoring sulfate or oxidation state ofsulfide to H2S under anaerobic condition. Because of an anaerobic environmentcondition in the sediments and bottom of water, large amounts of toxic H2S wasproduced by increasing SRB. Moreover, H2S pollute the water quality and poisonaquaculture species,and finally lead the farming environment to a vicious cycle.Inorder to better understanding the the Jiaozhou Bay farming environmental situationand the potential toxicity of H2S pollutants, site investigation and analysis of thesediment environment were done and the space distribution, diversity, phylogeny andabundance of microbial community were comprehensively analyzed.This study have selected four stations including breeding areas andnon-breeding areas. According to the eutrophication assessment that nitrogen andphosphorus act as evaluation parameters, A station belongs to theslightly-phosphorus-limited potential eutrophication, B station is nutritious, and C andD stations are oligotrophic. For sulfate-reducing bacteria, sulfur-oxidizing bacteriaand heterotrophic bacteria in the seawater, the amount in stations A and B of thebreeding area are significantly higher than that in the control station D, while stationC,which is a transition area, the number of bacteria are between station A andstation B;The amount of sulfate-reducing bacteria and sulfur-oxidizing bacteria in thesubsurface of sediment are basically more than that in sediment surface. And there areessentially the same number of heterotrophic bacteria in surface and subsurface. Application of Biolog in microbial community function show that the utilization ofcarbon source of four stations had no significate difference and they all raised with theincrease of time. Clustering analysis of DGGE profile in four stations showed thatsimilar relationship between A and D stations communities cluster into one group, Band C stations cluster into another group. While, the specific bands belonged to threegenus including Proteobacteria, Actinobacteria and Firmicutes, among wich theProteobacteria accounts for about70%.The results have revealed the ecological characteristics of the marineaquaculture environment, microbial community structure of sediment and waterinterface and sulfate-reducing process, which are of great significance. They alsoprovide the theoretical basis and data support for the prevention and governance ofmariculture environmental sulfide pollution.