Distribution of microbial lipids at an acid mine drainage site in China: Insights into microbial adaptation to extremely low pH conditions

ABSTRACT Acid mine drainage (AMD) is a major environmental problem affecting tens of thousands of kilometers of waterways worldwide. Passive bioremediation of AMD relies on microbial communities to oxidize and remove iron from the system; however, iron oxidation rates in AMD environments are highly variable among sites. At Scalp Level Run (Cambria County, PA), first-order iron oxidation rates are 10 times greater than at other coal-associated iron mounds in the Appalachians. We examined the bacterial community at Scalp Level Run to determine whether a unique community is responsible for the rapid iron oxidation rate. Despite strong geochemical gradients, including a >10-fold change in the concentration of ferrous iron from 57.3 mg/liter at the emergence to 2.5 mg/liter at the base of the coal tailings pile, the bacterial community composition was nearly constant with distance from the spring outflow. Scalp Level Run contains many of the same taxa present in other AMD sites, but the community is dominated by two strains of Ferrovum myxofaciens, a species that is associated with high rates of Fe(II) oxidation in laboratory studies. IMPORTANCE Acid mine drainage pollutes more than 19,300 km of rivers and streams and 72,000 ha of lakes worldwide. Remediation is frequently ineffective and costly, upwards of $100 billion globally and nearly $5 billion in Pennsylvania alone. Microbial Fe(II) oxidation is more efficient than abiotic Fe(II) oxidation at low pH (P. C. Singer and W. Stumm, Science 167:1121–1123, 1970, https://doi.org/10.1126/science.167.3921.1121 ). Therefore, AMD bioremediation could harness microbial Fe(II) oxidation to fuel more-cost-effective treatments. Advances will require a deeper understanding of the ecology of Fe(II)-oxidizing microbial communities and the factors that control their distribution and rates of Fe(II) oxidation. We investigated bacterial communities that inhabit an AMD site with rapid Fe(II) oxidation and found that they were dominated by two operational taxonomic units (OTUs) of Ferrovum myxofaciens, a taxon associated with high laboratory rates of iron oxidation. This research represents a step forward in identifying taxa that can be used to enhance cost-effective AMD bioremediation.

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1-Dimensional numerical modelling of unsaturated water flow and oxygen diffusion in overburden material column using hydrus 1-D

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/882/1/012064 ◽

2021 ◽

Vol 882 (1) ◽

pp. 012064

Author(s):

Jarwinda ◽

A Badhurahman ◽

G J Kusuma ◽

R S Gautama

Keyword(s):

Acid Mine Drainage ◽

Water Content ◽

Mine Drainage ◽

Negative Impact ◽

Low Ph ◽

Acid Mine ◽

Overburden Material ◽

Constant Head ◽

Unsaturated Condition ◽

And Diffusion

Abstract Coal mining activities, especially overburden material dumping can cause a negative impact into the environment, i.e., acid mine drainage, Acid mine drainage is characterized as low pH water with high sulphate and metal content produced from sulphidic-bearing overburden material with oxygen and water. In unsaturated condition, both of gaseous and water phases exist, acid mine drainage is generated. This study aims to characterize and model the water content in unsaturated condition and diffusion of oxygen of overburden material using the Hydrus 1-D software in a laboratory-scaled column. Laboratory-scaled column is initially filled with 75-cm height of dry overburden material and subjected into 5-cm constant head water level at the top of the column with free-flow condition at the bottom of column. The modelling result shows the water content of overburden material varies within depth and time elapsed and is saturated between 32400 minutes and 36000 minutes after initial wetting. Diffusivity of oxygen is linearly correlated with the water content of the overburden material at any given time and depth that varies between 1.34 × 10−7 m2/s and 8.80 × 10−12 m2/s. Water content and diffusivity of oxygen is expected to affect the generation of acid mine drainage in the overburden material.

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Behaviour of Fe, Mg and Ca in acid mine drainage and experimental solutions in the presence of Aspergillus niger species isolated from various environment

Nova Biotechnologica et Chimica ◽

10.36547/nbc.1116 ◽

2021 ◽

Vol 10 (1) ◽

Author(s):

Alexandra Šimonovičová ◽

Jana Barteková ◽

Ľubica Janovová ◽

Alena Luptáková

Keyword(s):

Aspergillus Niger ◽

Acid Mine Drainage ◽

Mine Drainage ◽

Low Ph ◽

Model Solution ◽

Acid Sulphate ◽

Acid Mine ◽

Mining Region

This article analyzes the ability of micromycetes to accumulate Fe, Mg and Ca from acid mine drainage (AMD) at the locality Smolník. Four strains of the Aspergillus niger (An) species originating from various types of environment were used in the experiments: the An-G strain (the locality of Gabčíkovo, Eutric Fluvisol), the An-P strain (the locality of Pezinok-Kolársky vrch, mining region with elevated amounts of As and Sb), the An-N strain (the locality of Nováky, mining region with elevated amounts of As and S), the An-Š strain (Banská ŠtiavnicaŠobov, the locality impacted by an acid sulphate weathering and extremely low pH). In the most cases the accumulation of Mg was the highest in comparison to accumulation of Fe. Accumulation of Ca was very low. Among the tested microfungi, the highest accumulation was noted by the strain An-N 55 % of Mg and by the strain An-Š 54 % of Fe from the model solution of the elements (Fe [1.67 mg/L], Mg [2.35 mg/L] and Ca [1.14 mg/L]).

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PRELIMINARY EVALUATION OF LIMESTONE-BASED PASSIVE TREATMENT SYSTEMS FOR LOW-pH ACID MINE DRAINAGE IN ANDEAN BOLIVIA

Journal American Society of Mining and Reclamation ◽

10.21000/jasmr12010426 ◽

2012 ◽

Vol 2012 (1) ◽

pp. 426-435

Author(s):

K.J. Palmer ◽

F. Llanos López ◽

R.R. Callapa ◽

A.A. Neptune ◽

A. Cisse ◽

...

Keyword(s):

Acid Mine Drainage ◽

Mine Drainage ◽

Low Ph ◽

Passive Treatment ◽

Preliminary Evaluation ◽

Acid Mine

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Evaluation and optimization of a new microbial enhancement plug-flow ditch system for the pretreatment of acid mine drainage: semi-pilot test

RSC Advances ◽

10.1039/c7ra10765j ◽

2018 ◽

Vol 8 (2) ◽

pp. 1039-1046 ◽

Cited By ~ 3

Author(s):

Yongwei Song ◽

Heru Wang ◽

Jun Yang ◽

Lixiang Zhou ◽

Jingcheng Zhou ◽

...

Keyword(s):

Heavy Metals ◽

Acid Mine Drainage ◽

Mine Drainage ◽

Plug Flow ◽

Low Ph ◽

Pilot Test ◽

High Concentration ◽

Acid Mine ◽

Dissolved Heavy Metals ◽

Microbial Enhancement

Acid mine drainage (AMD) is typically characterized by low pH, a high concentration of sulfate and dissolved heavy metals.

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Geochemical controls on the partitioning and hydrological transport of metals in a non-acidic river system

Hydrology and Earth System Sciences Discussions ◽

10.5194/hessd-11-9715-2014 ◽

2014 ◽

Vol 11 (8) ◽

pp. 9715-9758 ◽

Cited By ~ 8

Author(s):

J. Thorslund ◽

J. Jarsjö ◽

T. Wällstedt ◽

C. M. Mörth ◽

M. Y. Lychagin ◽

...

Keyword(s):

Acid Mine Drainage ◽

Lake Baikal ◽

Mine Drainage ◽

Drainage Basin ◽

Mining Site ◽

High Ph ◽

Acid Mine ◽

Guideline Values ◽

Ph Conditions ◽

Acidic River

Abstract. The speciation of metals, i.e. in which chemical form they occur, controls their mobility, bioavailability and toxicity. The overall objective of this study is to extend the knowledge on the spreading of metals in non-acidic river systems; this knowledge is currently much more limited than the knowledge on metal behavior under acidic conditions that for instance are found in acid mine drainage systems. We combine novel measurements of metal spreading under distinctly high-pH conditions (up to 9.6) in the Tuul River at the Zaamar Goldfield mining site (Upper Lake Baikal Drainage Basin, Mongolia) with a geochemical modelling approach (Visual MINTEQ). Total mass flows of several metals (Al, Cd, Fe, Mn, Pb and V) showed net increases over the mining site, with metals in suspension generally dominating the total export from the site. Model results showed that a main difference from acid mine drainage geochemistry is that the prevailing high pH causes precipitation of ferrihydrite and gibbsite, which removed between 90 to 100% of Fe and Al from solution. This notably influenced the behavior of As, Pb and V since their solubilities are controlled by sorption onto ferrihydrite. The combined effects from such geochemical processes (precipitation, sorption) hence explain the high impact of suspended transport to total transport under high pH conditions. Arsenic furthermore showed dissolved concentrations above health risk-based guideline values in several locations and can thus be of main toxic concern in the upper Lake Baikal Drainage Basin. Moreover, present modelling showed that in particular the solubility of Fe, Pb and Zn can increase considerably as DOC concentrations increase due to metal-organic complexation. In high pH systems, seasonality of DOC concentrations can therefore have a major influence on the spreading and toxicity of these metals, as can DOC trends caused by land use change. Present results also suggest that the behavior of Cr, Cu and Mo would be much better understood if a dependable adsorption database for hydroxyapatite could be developed.

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