Vertical diversity of sediment bacterial communities in 2 different trophic states （macrophyte-dominated and algae-dominated） of the large shallow eutrophic Lake Taihu, China, were investigated using denaturing grad...Vertical diversity of sediment bacterial communities in 2 different trophic states （macrophyte-dominated and algae-dominated） of the large shallow eutrophic Lake Taihu, China, were investigated using denaturing gradient gel electropfioresis （DGGE） and 16S rRNA sequence analysis. Clustering analysis of DGGE profiles showed that different clusters were recognized in different depths of sediment cores in the 2 lake trophic states. Analyses of the bacterial diversity, as estimated by the Shannon index （H＇）, showed that different sediment layers of the macrophyte-dominated state had higher diversity than the algae-dominated state. In addition, bacterial diversity of the sediment in the macrophyte-dominated state changed abruptly throughout the layers, but bacterial diversity of the algae-dominated state decreased gradually with sediment depth. Phylogenetic analysis showed that Proteobacteria was the most abundant phylum in the middle sediment of the 2 lake trophic states. In the macrophyte-dominated state, clone sequences related to Betaproteobacteria （50.0%） were the most abundant, followed by Epsilonproteobacteria （21.1%）, Acidobacteria （7.9%）, Deltaproteobacteria （7.9%）, Chloroflexi （7.9%）, and Bacteroidetes （5.3%）; whereas in the algae-dominated state, sequences affiliated with Betaproteobacteria （84.4%） were predominant, followed by Deltaproteobacteria （12.5%） and Acidobacteria （3.1%）. Canonical correspondence analysis showed that organic matter and pH play key roles in driving the vertical changes of bacterial community composition.展开更多
基金supported by the Key Program of Nanjing Institute of Geography and Limnology,Chinese Academy of Sciences (No. NIGLAS2012135002)the National Key Natural Science Foundation of China (No. 41230744)the Open Foundation from the State Key Laboratory of Nanjing Institute of Geography and Limnology,Chinese Academy of Sciences (No. 2010SKL008)
文摘Vertical diversity of sediment bacterial communities in 2 different trophic states （macrophyte-dominated and algae-dominated） of the large shallow eutrophic Lake Taihu, China, were investigated using denaturing gradient gel electropfioresis （DGGE） and 16S rRNA sequence analysis. Clustering analysis of DGGE profiles showed that different clusters were recognized in different depths of sediment cores in the 2 lake trophic states. Analyses of the bacterial diversity, as estimated by the Shannon index （H＇）, showed that different sediment layers of the macrophyte-dominated state had higher diversity than the algae-dominated state. In addition, bacterial diversity of the sediment in the macrophyte-dominated state changed abruptly throughout the layers, but bacterial diversity of the algae-dominated state decreased gradually with sediment depth. Phylogenetic analysis showed that Proteobacteria was the most abundant phylum in the middle sediment of the 2 lake trophic states. In the macrophyte-dominated state, clone sequences related to Betaproteobacteria （50.0%） were the most abundant, followed by Epsilonproteobacteria （21.1%）, Acidobacteria （7.9%）, Deltaproteobacteria （7.9%）, Chloroflexi （7.9%）, and Bacteroidetes （5.3%）; whereas in the algae-dominated state, sequences affiliated with Betaproteobacteria （84.4%） were predominant, followed by Deltaproteobacteria （12.5%） and Acidobacteria （3.1%）. Canonical correspondence analysis showed that organic matter and pH play key roles in driving the vertical changes of bacterial community composition.
