Analysis Of Water Quality And Bacterial Diversity Based On Pcr-dgge On East Lake,Nanhu Lake,Tangxun Lake In Wuhan City

With the development of urban industrialization,lake eutrophication is increasingly serious.As the main participant in nutrient cycle and energy flow,microorganisms play an extremely important role in the lake ecosystem.The change of the microbial community structure is closely related to the water quality of the lake.In order to describe the relationship between lake eutrophication and the bacterial communities structure in lakes,the water quality,including pH,temperature,ammonia nitrogen,total nitrogen,total phosphorus and COD are investigated in East lake,Nanhu lake and Tangxun lake.The PCR-DGGE method is applied to study water samples from Wuhan lakes.The results show that the comprehensive nutrition index of East lake has a regular tendency of October > August > December > February > April.The bigger index is 68.6 in October and the smaller one is 56.43 in April,thus the water quality is between light eutrophication and moderate eutrophication.The comprehensive nutrition index of Nanhu lake has a regular tendency of December > October > August > February > April.The bigger index is 107.50 in October and the smaller one is 96.72 in April,thus the water quality belongs to a very heavy eutrophication.The comprehensive nutrition index of Tangxun lake has a regular tendency of October > December > August > February > April.The bigger index is 89.00 in October and the smaller index is 73.81 in April,thus the water quality belongs to a heavy eutrophication.The comprehensive nutrition index of four areas of East lake in February 2014 has a tendency of D area > A area > B area > C area.The smaller comprehensive nutrition index is 53.32 in C area and the bigger one is 65.22 in D area,thus the water quality of the four areas is between light eutrophication and moderate eutrophication.The total number of bacteria in four areas is closely relative to the comprehensive nutrition index.The comprehensive nutrition index of three areas of Nanhu lake has a tendency of A area > C area > B area.The smaller comprehensive nutrition index is 94.14 in Nanhu C area and the bigger one is 107.31 in Nanhu A area.The water quality of the three areas belong to very heavy eutrophication.The total number of bacteria in three areas is relative to the comprehensive nutrition index.The comprehensive nutrition index in fishing area is 93.41,as for other areas is 72.21 in Tangxun lake.The total number of bacteria in fishing area is higher than other area.The total DNA of water bacteria in different areas of three lakes was extracted and PCR amplification was performed by using bacterial 16 S r DNA V3 area general primers.Analysis of DGGE fingerprint show that the bacterial community structure diversity index of four areas in East lake has a tendency of D area > A area> B area > C area.It has the same tendency with the comprehensive nutrition index.The bigger bacterial diversity index is 3.0265 and the smaller one is 2.6955.The bacterial community structure diversity index of three areas in Nanhu lake has a tendency of A area >C area >B area.It has the same tendency with the comprehensive nutrition index.The bigger bacterial diversity index is 3.2903 and the least index is 3.1439.The bacterial community structure diversity index of fishing area and other areas in Tangxun lake are 3.1160 and 2.9458,respectively.The comprehensive nutrition index of fishing is bigger than other areas.The comprehensive nutrition index of three lakes has the same change tendency with the bacterial community structure diversity index.The samples of Nanhu A area,Nanhu B area,East lake and Tangxun lake in April were chosen for DGGE.Results show that 29 different bands are detected in 12 samples.The bacterial diversity index is Nanhu A area > Nanhu B area > Tangxun lake > East lake.Based on the sequencing results,there are 19 edge bands,including one ?-Proteobacteria,one ?-Proteobacteria,one ?-Proteobacteria,three ?-Proteobacteria,two Bacteroidetes and eleven unclassified bacteria.The results of CCA suggest that ammonia nitrogen and total nitrogen have significant influence on the distribution of bands related species.