Bacterial community structure in reservoir sediments under the influence of antimony ore waste water

Abstract:

[Background] Microorganisms in reservoir sediments are an important part of the aquatic ecosystem and play an important role in the circulation of sediment materials. [Objective] To reveal the characteristics of bacterial community structure and the influencing factors in the surface sediments of the reservoir under the influence of antimony-containing wastewater. [Methods] Based on the Illumina high-throughput sequencing technology, the bacterial community structure of the surface sediments in Lengshuigou Reservoir was studied and its correlation with the physical and chemical properties of these sediments was analyzed too; the bacterial function was predicted and analyzed based on FAPROTAX. [Results] The high-throughput sequencing results showed that the bacterial community in Lengshuigou Reservoir is relatively rich, and could be divided into 81 phyla. The dominant phyla included Proteobacteria (40.32%-20.19%), Bacteroidetes (25.89%-4.44%) and Desulfobacter (9.43%-2.02%). Pearson correlation analysis indicated that different speciation of antimony are significantly correlated with a number of bacterial communities under different taxonomy levels. FAPROTAX was used to predict the function of bacteria. The results showed that aerobic heterotrophic bacteria dominated (14.59%-23.58% of the total bacteria), including chemoheterotrophic and aerobic heterotrophic bacteria. In addition, the relative abundance of functional microorganisms related to carbon, nitrogen and sulfur cycling and human pathogenic microorganisms (accounting for 12.42%-32.89% of the total bacteria) were also at a high level, which was significantly related to the geographical conditions of the reservoir and the surrounding environment and the type of pollutants. The heavy metal pollution load index method was used to evaluate the heavy metal pollution in the reservoir. [Conclusion] This study revealed the bacterial community structure characteristics and influencing factors in the sediments of the reservoir (built in 2015) affected by antimony mine wastewater, and analyzed and predicted the related functions of bacteria to study the biogeochemistry of antimony in the reservoir.

Key words:surficial sediments;wastewater containing antimony;bacterial community;bacterial function prediction