TY - JOUR

T1 - Bacterial and Archaeal Diversity in Sulfide-Bearing Waste Rock at Faro Mine Complex, Yukon Territory, Canada

AU - Pakostova, Eva

AU - Johnson, D. Barrie

AU - Bao, Zhongwen

AU - MacKenzie, Peter M.

AU - Ptacek, Carol. J.

AU - Blowes, David. W.

PY - 2020/6/1

Y1 - 2020/6/1

N2 - Acid mine/rock drainage (AMD/ARD) is generated by the microbially-accelerated oxidative dissolution of sulfide minerals in working and abandoned mine sites, and some natural environments. Iron-oxidizing microorganisms (IOM) regenerate the oxidant Fe3+, while sulfur-oxidizing microorganisms (SOM) contribute to AMD/ARD by generating H2SO4 via the oxidation of elemental S and reduced inorganic sulfur compounds. Bacterial and archaeal diversity in 34 samples of sulfide-bearing waste rock recovered from three boreholes at the Faro Mine Complex (Yukon Territory, Canada; Pb/Zn production from 1969 to 1998) was investigated using high-throughput amplicon sequencing of 16S rRNA genes. A majority of the borehole pore water samples had circum-neutral or mildly alkaline pH (6.3 − 8.7), while some had low pH (3.3 − 5.2). Mean relative abundance of prokaryotic SOM/IOM accounted for 3.4% of the total amplicons. The acidophilic genera Alicyclobacillus and Acidithiobacillus were the most abundant sulfur- and iron-metabolizing prokaryotes detected, followed by neutrophilic and moderately acidophilic (non-iron-oxidizing) SOM. Sulfate-reducing bacteria (SRB) were also detected, accounting for 0.6% of total reads. The presence of both acidophilic and neutrophilic prokaryotes catalyzing transformations of sulfur and iron in the same samples suggests development of microenvironments within the waste rock where dynamic biogeochemical transformations of these elements occur.

AB - Acid mine/rock drainage (AMD/ARD) is generated by the microbially-accelerated oxidative dissolution of sulfide minerals in working and abandoned mine sites, and some natural environments. Iron-oxidizing microorganisms (IOM) regenerate the oxidant Fe3+, while sulfur-oxidizing microorganisms (SOM) contribute to AMD/ARD by generating H2SO4 via the oxidation of elemental S and reduced inorganic sulfur compounds. Bacterial and archaeal diversity in 34 samples of sulfide-bearing waste rock recovered from three boreholes at the Faro Mine Complex (Yukon Territory, Canada; Pb/Zn production from 1969 to 1998) was investigated using high-throughput amplicon sequencing of 16S rRNA genes. A majority of the borehole pore water samples had circum-neutral or mildly alkaline pH (6.3 − 8.7), while some had low pH (3.3 − 5.2). Mean relative abundance of prokaryotic SOM/IOM accounted for 3.4% of the total amplicons. The acidophilic genera Alicyclobacillus and Acidithiobacillus were the most abundant sulfur- and iron-metabolizing prokaryotes detected, followed by neutrophilic and moderately acidophilic (non-iron-oxidizing) SOM. Sulfate-reducing bacteria (SRB) were also detected, accounting for 0.6% of total reads. The presence of both acidophilic and neutrophilic prokaryotes catalyzing transformations of sulfur and iron in the same samples suggests development of microenvironments within the waste rock where dynamic biogeochemical transformations of these elements occur.

KW - Acid mine drainage

KW - iron-oxidizers

KW - mine waste

KW - sulfur-oxidizers

KW - waste-rock dump

U2 - 10.1080/01490451.2020.1731020

DO - 10.1080/01490451.2020.1731020

M3 - Article

VL - 37

SP - 511

EP - 519

JO - Geomicrobiology Journal

JF - Geomicrobiology Journal

SN - 0149-0451

IS - 6

ER -