Identification and relative contributions of environmental driving factors for abundant and rare bacterial taxa to thermal stratification evolution

Ziwei Zhang; Chenbin Wu; Yiling Di; Jiafeng Zhang; Beibei Chai; Shilei Zhou

doi:10.1016/j.envres.2023.116424

Identification and relative contributions of environmental driving factors for abundant and rare bacterial taxa to thermal stratification evolution

Environ Res. 2023 Sep 1:232:116424. doi: 10.1016/j.envres.2023.116424. Epub 2023 Jun 14.

Authors

Ziwei Zhang¹, Chenbin Wu¹, Yiling Di¹, Jiafeng Zhang¹, Beibei Chai², Shilei Zhou³

Affiliations

¹ Pollution Prevention Biotechnology Laboratory of Hebei Province, School of Environmental Science and Engineering, Hebei University of Science and Technology, Shijiazhuang, 050018, PR China.
² Hebei Collaborative Innovation Center for the Regulation and Comprehensive Management of Water Resources and Water Environment, Hebei University of Engineering, Handan, 056038, PR China.
³ Pollution Prevention Biotechnology Laboratory of Hebei Province, School of Environmental Science and Engineering, Hebei University of Science and Technology, Shijiazhuang, 050018, PR China. Electronic address: ZSLZhouShilei@126.com.

PMID: 37327840
DOI: 10.1016/j.envres.2023.116424

Abstract

The thermal stratification of reservoir affects water quality, and water quality evolution is largely driven by microorganisms. However, few studies have been conducted on the response of abundant taxa (AT) and rare taxa (RT) to thermal stratification evolution in reservoirs. Here, using high-throughput absolute quantitative techniques, we examined the classification, phylogenetic diversity patterns, and assembly mechanisms of different subcommunities during different periods and investigated the key environmental factors driving community construction and composition. The results showed that community and phylogenic distances of RT were higher than AT (P < 0.001), and community and phylogenic distances of the different subcommunities were significantly positively correlated with the dissimilarity of environmental factors (P < 0.001). Nitrate (NO₃^--N) was the main driving factor of AT and RT in the water stratification period, and Mn was the main driving factor in the water mixing period (MP) based on redundancy analysis (RDA) and random forest analysis (RF). The interpretation rate of key environmental factors based on the selected indicator species in RT by RF was higher than that of AT, and Xylophilus (10.5%) and Prosthecobacter (0.1%) had the highest average absolute abundance in AT and RT during the water stable stratification period (SSP), whereas Unassigned had the highest abundance during the MP and weak stratification period (WSP). The network of RT and environmental factors was more stable than that of AT, and stratification made the network more complex. NO₃^--N was the main node of the network during the SSP, and manganese (Mn) was the main node during the MP. Dispersal limitation dominated community aggregation, the proportion of AT was higher than that of RT. Structural Equation Model (SEM) showed that NO₃^--N and temperature (T) had the highest direct and total effects on β-diversity of AT and RT for the SP and MP, respectively.

Keywords: Community assembly; Distribution pattern; Environmental factor; Network analysis; Stratified reservoir; Structural equation model.

MeSH terms

Bacteria / genetics
China
Phylogeny
Temperature
Water Microbiology*
Water Quality*