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In this paper, the traditional plate culture method conducted a survey of the number of bacteria and the metabolic characteristics of microbial communities tilapia farming systems and the Biolog ECO micro-plate method to analyze the relationship between environmental factors, and the advantages of bacteria from the aquaculture system in screening potential probiotic ability of degradation of organic matter, to provide useful guidance for health tilapia aquaculture management. The main findings of the study are as follows: tilapia farming systems study of the ecology of the microbial community in the period from May 2009 to October, Panyu District, Guangzhou City, a new generation of Fisheries Limited Sand North four farms tilapia aquaculture ponds investigation ( numbered # 1, # 2, # 3, # 4) water and sediment microbial community overall average dynamic changes. The results show that the water tilapia farming process the number of bacteria of the microbial community and the carbon source metabolic characteristics of fluctuations compared sediment, and by the impact of investment in antibacterial drug is also obvious. Microbial community functional diversity in June significantly reduced, primarily with L-arginine, glycine-L-glutamic acid, D, L-alpha-glycerol phosphate, 2 - hydroxybenzoic acid and putrescine five carbon source reduction of the flora in June. The number of bacteria and sediment microbial community carbon source metabolic characteristics of the entire breeding process to maintain a relatively stable state, less affected by antibacterial drugs. From 31 kinds of carbon source utilization characteristics of water and sediment microbial community structure, there are obvious similarities. The Pearson correlation coefficient analysis of the period from May 2009 to October tilapia aquaculture pond water and sediment microbial indicators and the relationship between water and sediment environmental factors indicators. The results show that the correlation between the microbial community of the body of water and aquatic environmental factors significantly compared with sediment. Water heterotrophic total bacterial count, pH and total organic carbon was a significant negative correlation; Bacillus number silicate was a significant positive correlation between total phosphorus was a significant negative correlation; metabolic activity of the microbial community and functional diversity sugars and their derivatives, fatty acids and lipids, metabolic intermediate and secondary metabolites carbon source utilization and phosphate content of the water column was significantly negatively correlated; microbial community metabolic intermediate and secondary metabolites the use of TP was significantly negatively correlated; showed a significant positive correlation between the functional diversity of microbial communities as well as the utilization of the metabolic intermediate and secondary metabolites in water nitrite content. Sediment There was no significant correlation between microbial indicators and sediment total nitrogen, total phosphorus, sulfur compounds and organic matter content. In November 2009 that tilapia farming final investigation and # 1, # 3, # 4 of pond water, sediment, and intestinal microbial community the number of bacteria and metabolic characteristics. The results show that the water in three ponds and intestinal microbial community metabolic characteristics similar to # 1 pond water and intestinal microbial community carbon source metabolic capacity was significantly lower than the # 3 and # 4 ponds; sediment microbial community carbon source metabolic characteristics little difference between the three ponds. 2 tilapia farming system potentially beneficial bacteria screening of dominant bacteria isolated from tilapia aquaculture system sieve 15 enzyme producing strain, of which 10 have higher protease activity, respectively, D30, D45, D50, D51, D53, D7, D11, D18, D21 and D55; 9 strains having higher amylase activity, respectively D17, D11, D38, D41, D45, D47, d51, D52 and D55. D51 and D53 protease activity is strongest, the highest enzyme activity gt; 70.0U/mL, D51 and D52 strongest amylase activity, the highest enzyme activity up to 267.86U/mL and 190.52U/mL Dl This 15 identification of bacteria by molecular biology, prima facie strain D50, D11, D18, D21 and D17 are Bacillus sp.; Strains D45, D51, D52, D41, D47 and D53 are Exiguobacterium sp.; The strains D55 is Aeromonas sp ; strains D30 belongs Agrobacteriumsp; strains D38 belonging of Arthrobacter sp.; the strain D7 belonging to Pseudomonas sp o Select D11, D45, D51, D55, D52 and D53 6 bacteria strains and organic degradation, the results show, this 6 bacteria obvious the organic feed lixivium degradation effect, significant degradation of organic matter in the feed in the culture supernatant, and can feed on the bottom of the sediment particles degradation.
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