锑矿废水影响下水库沉积物中细菌群落结构特征研究

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

摘要:

[背景] 水库沉积物中的微生物是水生态系统的重要组成部分，在沉积物物质循环中起重要作用。[目的] 揭示含锑废水影响下水库表层沉积物中细菌群落结构特征及影响因子。[方法] 基于Illumina高通量测序技术，对冷水沟水库表层沉积物细菌群落结构进行研究并分析其与沉积物理化性质的相关性；基于FAPROTAX软件对细菌功能进行预测分析。基于重金属污染负荷指数法评价水库重金属污染情况。[结果] 高通量测序结果表明冷水沟水库的细菌群落较为丰富，主要由变形菌门（Proteobacteria，40.32%-20.19%）、拟杆菌门（Bacteroidetes，25.89%-4.44%）、脱硫杆菌（Desulfobacter，9.43%-2.02%）等81个门570个属组成。相关性分析表明，不同提取形态的锑及水溶态锑与多个不同分类水平下的细菌群落有显著的相关性。FAPROTAX软件对细菌功能进行预测，结果表明，化能异养功能细菌占优势（占总细菌的14.59%-23.58%），包括化能异养（chemoheterotrophy）和需氧化能异养（aerobic chemoheterotrophy）；此外，与碳、氮、硫元素循环有关的功能微生物以及人类病原致病微生物的相对丰度（占总细菌的12.42%-32.89%）也较高，这与水库的地理条件、周边环境及污染物类型有较大的相关性。重金属污染负荷指数法评价结果表明，水库范围重金属污染较重。[结论] 研究区域受锑矿废水影响的水库（2015年建成蓄水）沉积物中细菌的群落以变形菌门（Proteobacteria）及拟杆菌门（Bacteroidetes）为最优势菌群，细菌功能主要以化能异养为主。

关键词:表层沉积物;含锑废水;细菌群落结构;细菌功能预测

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