Abstract
Bacteria and archaea (prokaryotes) are vital components for maintaining healthy function of groundwater ecosystems. The prokaryotic community composition and associated putative functional processes were examined in a shallow sandy aquifer in a wet-dry tropical environment. The aquifer had a contaminated gradient of saline mine-water, which primarily consisted of elevated magnesium (Mg2+) and sulfate (SO42−), although other major ions and trace metals were also present. Groundwaters were sampled from piezometers, approximately 2 m in depth, located in the creek channel upstream and downstream of the mine-water influence. Sampling occurred during the dry-season when only subsurface water flow was present. Next generation sequencing was used to analyse the prokaryote assemblages using 16S rDNA and metabolic functions were predicted with FAPROTAX. Significant changes in community composition and functional processes were observed with exposure to mine-waters. Communities in the exposed sites had significantly lower relative abundance of methanotrophs such as Methylococcaceae and methanogens (Methanobacteriaceae), but higher abundance in Nitrososphaeraceae, associated with nitrification, indicating potentially important changes in the biogeochemistry of the exposed sites. The changes were most strongly correlated with concentrations of SO42−, Mg2+ and Na+. This knowledge allows an assessment of the risk of mine-water contamination to groundwater ecosystem function and aids mine-water management.
Original language | English |
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Article number | 117318 |
Pages (from-to) | 1-11 |
Number of pages | 11 |
Journal | Environmental Pollution |
Volume | 284 |
Early online date | 12 May 2021 |
DOIs | |
Publication status | Published - Sept 2021 |
Bibliographical note
Funding Information:We pay our respects to all Traditional Owners of Kakadu National Park where we conducted this study and acknowledge Elders past, present and emerging. This study was funded by the Supervising Scientist Branch (SSB) of the Department of Agriculture, Water and the Environment and through an Australian Government Research Training Program Scholarship awarded to Lisa Chandler. We would like to thank Andrew Jansen, Julie Hanley, Costi Buccella, Ian Douglas, Matt Piamnok and Sam Walker (SSB) for assistance in the field and collection of samples. We are grateful to Brodie Sutcliffe for her support and guidance with the DNA extraction and amplification process, along with other members of the Macquarie University EGEEL Laboratory. We'd also like to thank Mirjam Kaestli (Charles Darwin University) for advice with statistical analysis. The authors declare that they have no conflicts of interest.
Funding Information:
We pay our respects to all Traditional Owners of Kakadu National Park where we conducted this study and acknowledge Elders past, present and emerging. This study was funded by the Supervising Scientist Branch (SSB) of the Department of Agriculture, Water and the Environment and through an Australian Government Research Training Program Scholarship awarded to Lisa Chandler. We would like to thank Andrew Jansen, Julie Hanley, Costi Buccella, Ian Douglas, Matt Piamnok and Sam Walker (SSB) for assistance in the field and collection of samples. We are grateful to Brodie Sutcliffe for her support and guidance with the DNA extraction and amplification process, along with other members of the Macquarie University EGEEL Laboratory. We'd also like to thank Mirjam Kaestli (Charles Darwin University) for advice with statistical analysis. The authors declare that they have no conflicts of interest.
Publisher Copyright:
© 2021
Copyright:
Copyright 2021 Elsevier B.V., All rights reserved.