Algae in Acid Mine Drainage and Relationships with Pollutants in a Degraded Mining Ecosystem

Acid mine drainage represents an extreme environment with high concentrations of potentially toxic elements and low pH values. These aquatic habitats are characterised by harsh conditions for biota, being dominated by acidophilic organisms. The study site, São Domingos mine, located in one of the largest metallogenetic provinces in the world, the Iberian Pyrite Belt, was closed without preventive measures. To identify the algae species and understand the relationships with abiotic parameters of the ecosystem, water and biological material were collected and analysed. Digital terrain models were obtained with an unmanned aerial vehicle for geomorphological and hydrologic characterisation of the mine degraded landscape. The results show two types of algal colours that seem to represent different degrees of photosynthetic activity. Optical and scanning electron microscopy revealed 14 taxa at the genus level, divided into eight classes. The genus Mougeotia is the most abundant multicellular algae. With respect to unicellular algae, diatoms are ubiquitous and abundant. Abiotic analyses expose typical features of acid mine drainage and support an inverse relationship between chemical contamination and biological diversity. Factorial correspondence analysis indicates three groups of attributes and samples by their relationship with specific toxic elements. This analysis also suggests a close association between Spirogyra and Pb, together composing a structurally simple ecosystem. The highest contamination in the river system is related to the hydrologic patterns obtained from photogrammetric products, such as the digital surface model and flow map accumulation, indicating the input of leachates from the section having the finest sulfide-rich wastes. Information about the algae community and their association with flow patterns of toxic elements is a relevant tool from a biomonitoring perspective.

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Extremely Acidophilic Protists from Acid Mine Drainage Host Rickettsiales-Lineage Endosymbionts That Have Intervening Sequences in Their 16S rRNA Genes

Applied and Environmental Microbiology ◽

10.1128/aem.69.9.5512-5518.2003 ◽

2003 ◽

Vol 69 (9) ◽

pp. 5512-5518 ◽

Cited By ~ 78

Author(s):

Brett J. Baker ◽

Philip Hugenholtz ◽

Scott C. Dawson ◽

Jillian F. Banfield

Keyword(s):

Acid Mine Drainage ◽

16S Rrna ◽

16S Rrna Gene ◽

Mine Drainage ◽

Close Association ◽

Variable Region ◽

16S Rrna Genes ◽

Rrna Genes ◽

Rrna Gene ◽

Acid Mine

ABSTRACT During a molecular phylogenetic survey of extremely acidic (pH < 1), metal-rich acid mine drainage habitats in the Richmond Mine at Iron Mountain, Calif., we detected 16S rRNA gene sequences of a novel bacterial group belonging to the order Rickettsiales in the Alphaproteobacteria. The closest known relatives of this group (92% 16S rRNA gene sequence identity) are endosymbionts of the protist Acanthamoeba. Oligonucleotide 16S rRNA probes were designed and used to observe members of this group within acidophilic protists. To improve visualization of eukaryotic populations in the acid mine drainage samples, broad-specificity probes for eukaryotes were redesigned and combined to highlight this component of the acid mine drainage community. Approximately 4% of protists in the acid mine drainage samples contained endosymbionts. Measurements of internal pH of the protists showed that their cytosol is close to neutral, indicating that the endosymbionts may be neutrophilic. The endosymbionts had a conserved 273-nucleotide intervening sequence (IVS) in variable region V1 of their 16S rRNA genes. The IVS does not match any sequence in current databases, but the predicted secondary structure forms well-defined stem loops. IVSs are uncommon in rRNA genes and appear to be confined to bacteria living in close association with eukaryotes. Based on the phylogenetic novelty of the endosymbiont sequences and initial culture-independent characterization, we propose the name “Candidatus Captivus acidiprotistae.” To our knowledge, this is the first report of an endosymbiotic relationship in an extremely acidic habitat.

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Genetically inherited tolerance may unveil trait dominance patterns in an amphibian model

Scientific Reports ◽

10.1038/s41598-019-55838-9 ◽

2019 ◽

Vol 9 (1) ◽

Author(s):

E. Fasola ◽

R. Ribeiro ◽

I. Lopes

Keyword(s):

Acid Mine Drainage ◽

Mine Drainage ◽

Natural Populations ◽

Genetic Erosion ◽

Egg Mass ◽

Chemical Contamination ◽

Time To Death ◽

Acid Mine ◽

Initial Hypothesis ◽

Genetically Determined

AbstractChemical contamination may cause genetic erosion in natural populations by wiping out the most sensitive genotypes. This is of upmost concern if the loss of genetic variability is irreversible due to contaminant-driven elimination of alleles, which may happen if tolerance is a recessive or incompletely dominant trait – the recessive tolerance inheritance (working-) hypothesis. Accordingly, this work investigated the tolerance inheritance to lethal levels of a metal-rich acid mine drainage (AMD) and to copper sulphate in a population of Pelophylax perezi. Time-to-death for each egg, after being exposed to 60% of a sample of acid mine drainage and to 9 mg/L Cu, was registered, and, for each egg mass, the median lethal time (LT50) and respective quartiles (LT25 and LT75) were computed. Results suggested that genetically determined tolerance could be probably driven by incomplete dominance (with possible maternal effect influence), preliminarily supporting the initial hypothesis.

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Microbiological monitoring of acid mine drainage treatment systems and aquatic surroundings using real-time PCR

Water Science & Technology ◽

10.2166/wst.2009.230 ◽

2009 ◽

Vol 59 (11) ◽

pp. 2083-2091 ◽

Cited By ~ 2

Author(s):

J. S. Han ◽

C. G. Kim

Keyword(s):

Water Quality ◽

Acid Mine Drainage ◽

Real Time ◽

Real Time Pcr ◽

Biological Diversity ◽

Mine Drainage ◽

Treatment System ◽

Microbiological Monitoring ◽

Mining Areas ◽

Acid Mine

In general, acid mine drainage (AMD) causes low pH and high metal concentrations in mining areas and surroundings. The aim of this research was to achieve microbiological monitoring for AMD and to assess whether mine water outflows have any ecological effects on the aqueous ecosystem receiving effluents from different types of treatment system. The water quality of aquatic sample was analyzed and the molecular biological diversity of the samples was assessed using 16S rRNA methods, which were implemented to determine which bacteria existed throughout various unit processes for different AMD treatment systems and their receiving water environments. Acidiphilium cryptum, a heterotrophic acidophile, was found at the AMD sites, and Rhodoferax ferrireducens, which can reduce iron using insoluble Fe(III) as an electron acceptor, was detected at many AMD treatment facilities and downstream of the treatment processes. Subsequently, quantitative real-time PCR was conducted on specific genes of selected bacteria. Surprisingly, obvious trends were observed in the relative abundance of the various bacteria that corresponded to the water quality analytical results. The copy number of Desulfosporosinus orientus, a sulfate reducing bacteria, was also observed to decrease in response to decreases in metals according to the downstream flow of the AMD treatment system.

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Mineralogy and chemistry of ochre sediments from an acid mine drainage near a disused mine in Cornwall, UK

Clay Minerals ◽

10.1180/000985599546172 ◽

1999 ◽

Vol 34 (2) ◽

pp. 301-317 ◽

Cited By ~ 29

Author(s):

Balwant Singh ◽

M. J. Wilson ◽

W. J. McHardy ◽

A. R. Fraser ◽

G. Merrington

Keyword(s):

Acid Mine Drainage ◽

Photoelectron Spectroscopy ◽

Mine Drainage ◽

Close Association ◽

Ammonium Oxalate ◽

X Ray Diffraction ◽

Thermal Methods ◽

X Ray ◽

Acid Mine ◽

Transmission Electron

AbstractOchre sediments from acid mine drainage in Cornwall have been investigated using X-ray diffraction, thermal methods, infrared spectroscopy, X-ray photoelectron spectroscopy, transmission electron microscopy and chemical methods in order to determine their mineralogical and chemical composition. Fresh sediments consist of ferrihydrite and goethite. Large fractions of these minerals are dissolved by the ammonium oxalate treatment reflecting their poorly crystalline structure. Fresh sediments contain large amounts of surface-adsorbed SO4 (up to 9.3%) which is readily desorbed by the PO4 treatment. Goethite is the only mineral present in relatively older sediments and the mineral is well crystallized with rod-shaped morphology. Environmental conditions, such as pH and SO4 content, are not favourable for the presence of schwertmannite at the site. Iron minerals appear to be precipitating around filamentous algae and the shape of algae is preserved in the Fe oxide matrix. The ubiquitous presence of algae in close association with Fe minerals indicate their possible role in the crystallization of Fe oxides.

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Performance Evaluation of Fe-Al Bimetallic Particles for the Removal of Potentially Toxic Elements from Combined Acid Mine Drainage-Effluents from Refractory Gold Ore Processing

Minerals ◽

10.3390/min11060590 ◽

2021 ◽

Vol 11 (6) ◽

pp. 590

Author(s):

Elham Aghaei ◽

Zexiang Wang ◽

Bogale Tadesse ◽

Carlito Tabelin ◽

Zakaria Quadir ◽

...

Keyword(s):

Acid Mine Drainage ◽

Electrochemical Reduction ◽

Toxic Elements ◽

Mine Drainage ◽

Chloride Ions ◽

Potentially Toxic Elements ◽

Dissolved Metals ◽

Bimetallic Particles ◽

Acid Mine ◽

Electrode Potentials

Acid mine drainage (AMD) is a serious environmental issue associated with mining due to its acidic pH and potentially toxic elements (PTE) content. This study investigated the performance of the Fe-Al bimetallic particles for the treatment of combined AMD-gold processing effluents. Batch experiments were conducted in order to eliminate potentially toxic elements (including Hg, As, Cu, Pb, Ni, Zn, and Mn) from a simulated waste solution at various bimetal dosages (5, 10, and 20 g/L) and time intervals (0 to 90 min). The findings show that metal ions with greater electrode potentials than Fe and Al have higher affinities for electrons released from the bimetal. Therefore, a high removal (> 95%) was obtained for Hg, As, Cu, and Pb using 20 g/L bimetal in 90 min. Higher uptakes of Hg, As, Cu, and Pb than Ni, Zn, and Mn also suggest that electrochemical reduction and adsorption by Fe-Al (oxy) hydroxides as the primary and secondary removal mechanisms, respectively. The total Al3+ dissolution in the experiments with a higher bimetal content (10 and 20 g/L) were insignificant, while a high release of Fe ions was recorded for various bimetal dosages. Although the secondary Fe pollution can be considered as a drawback of using the Fe-Al bimetal, this issue can be tackled by a simple neutralization and Fe precipitation process. A rapid increase in the solution pH (initial pH 2 to >5 in 90 min) was also observed, which means that bimetallic particles can act as a neutralizing agent in AMD treatment system and promote the precipitation of the dissolved metals. The presence of chloride ions in the system may cause akaganeite formation, which has shown a high removal capacity for PTE. Moreover, nitrate ions may affect the process by competing for the released electrons from the bimetal owing to their higher electrode potential than the metals. Finally, the Fe-Al bimetallic material showed promising results for AMD remediation by electrochemical reduction of PTE content, as well as acid-neutralization/metal precipitation.

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Evaluation of the Affinity of Some Toxic Elements to Schwertmannite in Natural Streams Contaminated with Acid Mine Drainage

Water Air & Soil Pollution ◽

10.1007/s11270-010-0523-9 ◽

2010 ◽

Vol 216 (1-4) ◽

pp. 153-166 ◽

Cited By ~ 6

Author(s):

Tetsushi Nagano ◽

Nobuyuki Yanase ◽

Yukiko Hanzawa ◽

Morio Takada ◽

Hisayoshi Mitamura ◽

...

Keyword(s):

Acid Mine Drainage ◽

Toxic Elements ◽

Mine Drainage ◽

Acid Mine ◽

Natural Streams

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Insights into the Diversity of Eukaryotes in Acid Mine Drainage Biofilm Communities

Applied and Environmental Microbiology ◽

10.1128/aem.02500-08 ◽

2009 ◽

Vol 75 (7) ◽

pp. 2192-2199 ◽

Cited By ~ 75

Author(s):

Brett J. Baker ◽

Gene W. Tyson ◽

Lindsey Goosherst ◽

Jillian F. Banfield

Keyword(s):

Acid Mine Drainage ◽

18S Rrna ◽

Mine Drainage ◽

Sequence Similarity ◽

Extreme Environment ◽

18S Rrna Gene ◽

Trophic Levels ◽

Ecosystem Functions ◽

Rrna Gene ◽

Acid Mine

ABSTRACT Microscopic eukaryotes are known to have important ecosystem functions, but their diversity in most environments remains vastly unexplored. Here we analyzed an 18S rRNA gene library from a subsurface iron- and sulfur-oxidizing microbial community growing in highly acidic (pH < 0.9) runoff within the Richmond Mine at Iron Mountain (northern California). Phylogenetic analysis revealed that the majority (68%) of the sequences belonged to fungi. Protists falling into the deeply branching lineage named the acidophilic protist clade (APC) and the class Heterolobosea were also present. The APC group represents kingdom-level novelty, with <76% sequence similarity to 18S rRNA gene sequences of organisms from other environments. Fluorescently labeled oligonucleotide rRNA probes were designed to target each of these groups in biofilm samples, enabling abundance and morphological characterization. Results revealed that the populations vary significantly with the habitat and no group is ubiquitous. Surprisingly, many of the eukaryotic lineages (with the exception of the APC) are closely related to neutrophiles, suggesting that they recently adapted to this extreme environment. Molecular analyses presented here confirm that the number of eukaryotic species associated with the acid mine drainage (AMD) communities is low. This finding is consistent with previous results showing a limited diversity of archaea, bacteria, and viruses in AMD environments and suggests that the environmental pressures and interplay between the members of these communities limit species diversity at all trophic levels.

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