Dataset Information

Bacterial communities in the sediments of Dianchi Lake, a partitioned eutrophic waterbody in China.

ABSTRACT: Bacteria play an important role in the decomposition and cycling of a variety of compounds in freshwater aquatic environments, particularly nutrient-rich eutrophic lakes. A unique Chinese eutrophic lake--Dianchi--was selected for study because it has two separate and distinct basins, Caohai with higher organic carbon levels and Waihai with lower organic carbon levels. Sediment bacterial communities were studied in the two basins using samples collected in each season from June 2010 to March 2011. Barcoded pyrosequencing based on the 16 S rRNA gene found that certain common phyla, Proteobacteria, Bacteroidetes, Firmicutes and Chloroflexi, were dominant in the sediments from both basins. However, from the class to genus level, the dominant bacterial groups found in the sediments were distinct between the two basins. Correlation analysis revealed that, among the environmental parameters examined, total organic carbon (TOC) accounted for the greatest proportion of variability in bacterial community. Interestingly, study results suggest that increasing allochthonous organic carbon could enhance bacterial diversity and biomass in the sediment. In addition, analysis of function genes (amoA and nosZ) demonstrated that ammonia-oxidizing bacteria (AOB) were dominant in sediments, with 99% belonging to Nitrosomonas. Denitrifying bacteria were comparatively diverse and were associated with some cultivatable bacteria.

SUBMITTER: Bai Y

PROVIDER: S-EPMC3364273 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Bacterial communities in the sediments of Dianchi Lake, a partitioned eutrophic waterbody in China.

Bai Yaohui Y Shi Qing Q Wen Donghui D Li Zongxun Z Jefferson William A WA Feng Chuanping C Tang Xiaoyan X

PloS one 20120530 5

Bacteria play an important role in the decomposition and cycling of a variety of compounds in freshwater aquatic environments, particularly nutrient-rich eutrophic lakes. A unique Chinese eutrophic lake--Dianchi--was selected for study because it has two separate and distinct basins, Caohai with higher organic carbon levels and Waihai with lower organic carbon levels. Sediment bacterial communities were studied in the two basins using samples collected in each season from June 2010 to March 2011 ...[more]

PMID: 22666393

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Project description:BackgroundBacterial community play a key role in environmental and ecological processes in river ecosystems. Rivers are used as receiving body for treated and untreated urban wastewaters that brings high loads of sewage and excrement bacteria. However, little is known about the bacterial community structure and functional files in the rivers around the eutrophic Chaohu Lake, the fifth largest freshwater lake in China, has been subjected to severe eutrophication and cyanobacterial blooms over the past few decades. Therefore, understanding the taxonomic and functional compositions of bacterial communities in the river will contribute to understanding aquatic microbial ecology. The main aims were to (1) examine the structure of bacterial communities and functional profiles in this system; (2) find the environmental factors of bacterial community variations.ResultsWe studied 88 sites at rivers in the Chaohu Lake basin, and determined bacterial communities using Illumina Miseq sequencing of the 16 S rRNA gene, and predicted functional profiles using PICRUSt2. A total of 3,390,497 bacterial 16 S rRNA gene sequences were obtained, representing 17 phyla, and 424 genera; The dominant phyla present in all samples were Bacteroidetes (1.4-82.50 %), followed by Proteobacteria (12.6-97.30 %), Actinobacteria (0.1-17.20 %). Flavobacterium was the most numerous genera, and accounted for 0.12-80.34 % of assigned 16 S reads, followed by Acinetobacter (0.33-49.28 %). Other dominant bacterial genera including Massilia (0.06-25.40 %), Psychrobacter (0-36.23 %), Chryseobacterium (0.01-22.86 %), Brevundimonas (0.01-12.82 %), Pseudomonas (0-59.73 %), Duganella (0.08-23.37 %), Unidentified Micrococcaceae (0-8.49 %). The functional profiles of the bacterial populations indicated an relation with many human diseases, including infectious diseases. Overall results, using the β diversity measures, coupled with heatmap and RDA showed that there were spatial variations in the bacterial community composition at river sites, and Chemical oxygen demand (CODMn) and (NH4+ )were the dominant environmental drivers affecting the bacterial community variance.ConclusionsThe high proportion of the opportunistic pathogens (Acinetobacter, Massilia, Brevundimonas) indicated that the discharge of sewage without adequate treatment into the rivers around Chaohu Lake. We propose that these bacteria could be more effective bioindicators for long-term sewage monitoring in eutrophic lakes.

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Dataset Information

Bacterial communities in the sediments of Dianchi Lake, a partitioned eutrophic waterbody in China.

Publications

Bacterial communities in the sediments of Dianchi Lake, a partitioned eutrophic waterbody in China.

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