Screening And Preliminary Application Of Nitrifying Bacteira From Sediments Of Luoshijiang Wetland

ObjectiveThis study choose sediments of Luoshijiang wetland as material from threepositions upstream,centre of wetland and estuary investigating distribution ofnitrifying bacteria and screen bacteria that are vigoroso in degradating ammonianitrogen. In the end we want to treat some simple sewage with them after a test oftheir ability distribution in the water rich in ammonia nitrogen manual prepared. If thetest succeed,it can be used in biodenitrification technology in lake Erhai as a actualreference.MethodsThis study will investigate distribution of nitrifying bacteria in sediment ofLuoshijiang wetland by screening culturable nitrifying bacteria who are regarded asthe research object in it and verifying if there is some difference among the threeposition with the analysis of SPSS19.0.After a test of ammonia nitrogen degradationability, those who have the higher rate than others in degradation will be filtered.After identifition by VITEK2-Compact automatic microorganisms analyzer withmorphological specificity, physiological and biochemical tests, the bacteria will beserved as a actual reference by trying out with some sewage.Results1.The culturable nitrifying bacteria in upstream，centre of wetland and estuary insediments of Luoshijiang wetland is1.6×105/ml、1.1×105/ml、0.8×105/ml by MPN.But there is no statistical difference in the number of nitrifying bacteria filtered ofthose three positions finally by SPSS19.0.2.In this study47strains of culturable nitrifying bacteria were screened fromthree positions of Luoshijiang sediment.But some of them lost a fine degradation rateof ammonia nitrogen. So only3strains named L-A、L-C1and L-C2outstand of it with a decomposition rate of up to77.7%about12.73mg/（L·d）within6days underthe conditions of35℃,120r/min.3.The3strains bacteria with higher decomposition are G-Brevibacterium andnon-fermentative. They are facultative heterotrophic because growing well not onlyon marine mineral culture but also on another culture rich in carbon source. L-Agenerates a green pigment and its colony is gray-green and random-shaped and L-C1and L-C2are rounded,ivory-white.L-A is Pseudomonas aeruginosa,L-C1isAcinetobacter baumannii and L-C2is Hemolytic acinetobacter by automaticmicroorganisms analyzer.4. There is no statistical difference in the sewage of discharge bay before andafter adding the bacteria.But the same processing appeared opposite results in aerationtank and suction sump,which is the rising in concentration of DN、TN and NH4+-Nand the reducing of NO3--N at the same time.5.The concentration of those different forms of nitrogen will changed after beingadded with the single L-A、 L-C1or L-C2.What the change is the rising inconcentration of DN、TN and NH4+-N and the reducing of NO3--N.6.L-A、L-C1and L-C2can remove ammonia nitrogen to varying degrees. Thereduction of it are positive number all and the decomposition rate are11.9%，12.5%，11.4%with sewage from aeration tank and12.5%，16.4%，11,3%with suctionsump sewage.Conclusions1.There is no difference in the distribution of upstream，centre of wetland andestuary of sediments from Luoshijiang wetland in this study.2.We screen47strains of culturable bacteria and there are3of them arefacultative heterotrophic bacteria being vested in nitrite bacteria. They have a naturalammonia nitrogen degradation ability with a higher rate than others and the most rateis77.7%about12.73(mg/L·d) in manual configuration of culture. L-A isPseudomonas aeruginosa，L-C1is Acinetobacter baumannii and L-C2is Hemolyticacinetobacter by automatic microorganisms analyzer.3.The three kinds of sewage are partial acidic (PH<7) in this study.The watertemperature and acidity of them are aeration tank> discharge bay> suction sump.4.Those3strains of culturable bacteria all have varying degrees of ammonia nitrogen degradation ability.They can remove some DN、TN and NH4+-N at the sametime NO3--N is added in sewage of aeration tank and suction sump.The arrangementof degradation rate of them are L-C1＞L-A＞L-C2being similar to the situation inmanual configuration of culture.5.Those3strains of culturable bacteria are accessible and growing well inmanual configuration of culture.They have a natural ammonia nitrogen degradationability could be served as bacteria to remove ammonia nitrogen of sewage in reserve.