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Enviroscan Ukrainian Institute of Speleology and Karstology


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Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

New publications on hypogene speleogenesis

Klimchouk on 26 Mar, 2012
Dear Colleagues, This is to draw your attention to several recent publications added to KarstBase, relevant to hypogenic karst/speleogenesis: Corrosion of limestone tablets in sulfidic ground-water: measurements and speleogenetic implications Galdenzi,

The deepest terrestrial animal

Klimchouk on 23 Feb, 2012
A recent publication of Spanish researchers describes the biology of Krubera Cave, including the deepest terrestrial animal ever found: Jordana, Rafael; Baquero, Enrique; Reboleira, Sofía and Sendra, Alberto. ...

Caves - landscapes without light

akop on 05 Feb, 2012
Exhibition dedicated to caves is taking place in the Vienna Natural History Museum   The exhibition at the Natural History Museum presents the surprising variety of caves and cave formations such as stalactites and various crystals. ...

Did you know?

That embryo is a developing individual before its birth or hatching [23].?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms


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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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Featured articles from other Geoscience Journals
Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
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Your search for microbiology (Keyword) returned 69 results for the whole karstbase:
Showing 16 to 30 of 69
Acidic cave-wall biofilms located in the Frasassi Gorge, Italy, 2000,
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Vlasceanu L. , Sarbu S. M. , Engel A. S. , Kinkle B. K. ,
Acidic bioflms present on cave walls in the sulfidic region of the Frasassi Gorge, Italy, were investigated to determine their microbial composition and their potential role in cave formation and ecosystem functioning. All biofilm samples examined had pH values <1.0. Scanning electron microscopy of the biofilms revealed the presence of various filaments and rods associated in large clusters with mineral crystals. Qualitative energy-dispersive x-ray analysis was used to determine that the crystals present on the cave walls, associated with the microbial biofilm, were composed of calcium and barium sulfate. Ribosomal RNA-based methods to determine the microbial composition of these biofilms revealed the presence of at least two strains of potential acidophilic, sulfur-oxidizing bacteria, belonging to the genera Thiobacillus and Sulfobacillus. An acid producing strain of Thiobacillus sp. also was obtained in pure culture. Stable isotope ratio analysis of carbon and nitrogen showed that the wall biofilms are isotopically light, suggesting that in situ chemoautotrophic activity plays an important role in this subsurface ecosystem

Geomicrobiology and redox geochemistry of the karstified Miocene gypsum aquifer, Western Ukraine: A study from Zoloushka Cave., 2001,
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Andrejchuk V. N. , Klimchouk A. B.
The gypsum karst of the western Ukraine developed largely under artesian conditions. The Miocene aquifer is presently entrenched and dewatered over much of the territory, while it remains confined in the zone adjacent to the Carpathian Foredeep. The most prominent geochemical features of the Miocene aquifer system in the confined karst zone are: 1) the almost universal presence of a bioepigenetic calcite bed, enriched in the light carbon isotope, at the top of the gypsum (the "Ratynsky Limestone"), 2) the widespread sulfur mineralization associated with the above calcite bed (the region is one of the world's largest sulfur-bearing basins), and 3) high H2S and CO2 in the groundwater. Intense microbial sulfate-reduction processes occur in the gypsum in this zone. Zoloushka Cave is the third longest (92 km) and the largest by volume (more than 7 x 105 m3) gypsum cave in the world. It is a unique example of a young artesian cave that only during the Holocene became partly drained and during the last 50 years progressively dewatered due to a quarry operation. These rapid changes have induced a number of transitional geochemical processes, some of which appear to be bacterially mediated. Six groups of microorganisms have been identified in the cave. The paper discusses the aquifer geochemistry during the transitional stage in the light of the microbiological studies.

Geomicrobiology and redox geochemistry of the karstified Miocene gypsum aquifer, western Ukraine: The study from Zoloushka Cave, 2001,
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Andrejchuk Vn, Klimchouk Ab,
The gypsum karst of the western Ukraine developed largely under artesian conditions. The Miocene aquifer is presently entrenched and dewatered over much of the territory, while it remains confined in the zone adjacent to the Carpathian Foredeep. The most prominent geochemical features of the Miocene aquifer system in the confined karst zone are: (1) the almost universal presence of a bioepigenetic calcite bed, enriched in the light carbon isotope, at the top of the gypsum (the 'Ratynsky Limestone'), (2) the widespread sulfur mineralization associated with the above calcite bed (the region is one of the world's largest sulfur-bearing basins), and (3) high H2S and CO2 in the groundwater. Intense microbial sulfate-reduction processes occur in the gypsum in this zone. Zoloushka Cave is the third longest (92 km) and the largest by volume (more than 7 x 10(5) m(3)) gypsum cave in the world. It is a unique example of a young artesian cave that only during the Holocene became partly drained and during the last 50 years progressively dewatered due to a quarry operation. These rapid changes have induced a number of transitional geochemical processes, some of which appear to be bacterially mediated. Six groups of microorganisms have been identified in the cave. Our article discusses the aquifer geochemistry during the transitional stage in the light of the microbiological studies

Morphoanalysis of bacterially precipitated subaqueous calcium carbonate from Weebubbie Cave, Australia, 2001,
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Contos Ak, James Jm, Heywood B, Pitt K, Rogers P,
In this article, we present a previously unreported morphology of bacterially precipitated calcite (determined using XRD, FTIR, and SAED) occurring subaqueously in Weebubbie Cave. Observations using FESEM and TEM revealed spindle-shaped crystals with curved [hk.0] faces lying parallel to the c-axis. Calcite precipitated under conditions designed to mimic the inorganic solution chemistry of the cave revealed a different morphology. These differences between the crystals suggest that the formation of the cave crystals is a consequence of biologically activity

Ecological assessment and geological significance of microbial communities from Cesspool Cave, Virginia, 2001,
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Engel As, Porter Ml, Kinkle Bk, Kane Tc,
Microbial mats from hydrogen sulfide-rich waters and cave-wall biofilms were investigated from Cesspool Cave, Virginia, to determine community composition and potential geomicrobiological functioning of acid-producing bacteria. Rates of microbial mat chemoautotrophic productivity were estimated using [C-14]-bicarbonate incorporations and microbial heterotrophy was determined using [C-14]-leucine incubations. Chemoautotrophic fixation was measured at 30.4 12.0 ng C mg dry wt(1) h(1), whereas heterotrophic productivity was significantly less at 0.17 0.02 ng C mg dry wt(1) h(1). The carbon to nitrogen ratios of the microbial mats averaged 13.5, indicating that the mats are not a high quality food source for higher trophic levels. Ribosomal RNA-based methods were used to examine bacterial diversity in the microbial mats, revealing the presence of at least five strains of bacteria. The identity of some of the strains could be resolved to the genus Thiothrix and the Flexibacter-Cytophaga-Bacteriodes phylum, and the identity of the remaining strains was to either the Helicobacter or Thiovulum group. Two of 10 sulfur-oxidizing, chemoautotrophic pure cultures of Thiobacillus spp. (syn. Thiomonas gen. nov.) demonstrated the ability to corrode calcium carbonate, suggesting that the colonization and metabolic activity of these bacteria may be enhancing cave enlargement

Microbial activity in caves - a geological perspective., 2001,
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Jones B.

Geomicrobiology of caves: A review, 2001,
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Northup D. E. , Lavoie K. H. ,
In this article, we provide a review of geomicrobiological interactions in caves, which are nutrient-limited environments containing a variety of redox interfaces. Interactions of cave microorganisms and mineral environments lead to the dissolution of, or precipitation on, host rock and speleothems (secondary mineral formations). Metabolic processes of sulfur-, iron-, and manganese-oxidizing bacteria can generate considerable acidity, dissolving cave walls and formations. Examples of possible microbially influenced corrosion include corrosion residues (e.g., Lechuguilla and Spider caves, New Mexico, USA), moonmilk from a number of caves (e.g., Spider Cave, New Mexico, and caves in the Italian Alps), and sulfuric acid speleogenesis and cave enlargement (e.g., Movile Cave, Romania, and Cueva de Villa Luz, Mexico). Precipitation processes in caves, as in surface environments, occur through active or passive processes. In caves, microbially induced mineralization is documented in the formation of carbonates, moonmilk, silicates, clays, iron and manganese oxides, sulfur, and saltpeter at scales ranging from the microscopic to landscape biokarst. Suggestions for future research are given to encourage a move from descriptive, qualitative studies to more experimental studies

Iron oxide-rich filaments: Possible fossil bacteria in Lechuguilla Cave, New Mexico, 2001,
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Provencio P. P. , Polyak V. J. ,
Reddish filaments in two fragments of unusual iron oxide bearing stalactites, 'the Rusticles' from Lechuguilla Cave, New Mexico, are found only within the central canals of the Rusticles. The curved, helical, and/or vibrioidal filaments vary from 1 to 6 mum in outer diameter and 10 to >50 mum in length. SEM and TEM show the filaments have 0.5-mum diameter central tubes, with goethite crystals radiating outwardly along their lengths. The diameter of the central tubes is consistent with the diameter of many iron-oxidizing filamentous bacteria. Although most iron oxide depositing bacteria do not deposit well-crystallized radiating goethite, we propose thick hydrous iron oxide was slowly crystallized from amorphous material to goethite, in place, over a relatively long period of time. From the gross morphology and the particular setting, we suggest this represents an occurrence of fossilized, acidophilic iron-oxidizing bacteria

Screening for culturable microorganisms from cave environments (Slovenia), 2002,
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Mulec Janez, Zalar Polona, Zupan Hajna Nadja , Rupnik Maja

Various microenvironments in three different caves were screened for the presence of indigenous culturable microorganisms: extremely weathered limestone in Pečina v Borštu and Martinska jama, cave silver and calcite rafts on the surface of subterranean ponds in Pečina v Borštu and calcite moonmilk speleotheme in Snežna jama of Raduha mountain. The counts of viable cells collected are supplemented with laboratory data necessary to establish genus or wider taxonomic group level identity of isolates. Besides other bacterial and fungal groups flourescent pseudomonads are prevailing among isolates.


Filamentous 'Epsilonproteobacteria' dominate microbial mats from sulfidic cave springs, 2003,
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Engel As, Lee N, Porter Ml, Stern La, Bennett Pc, Wagner M,
Hydrogen sulfide-rich groundwater discharges from springs into Lower Kane Cave, Wyoming, where microbial mats dominated by filamentous morphotypes are found. The full-cycle rRNA approach, including 16S rRNA gene retrieval and fluorescence in situ hybridization (FISH), was used to identify these filaments. The majority of the obtained 16S rRNA gene clones from the mats were affiliated with the 'Epsilonproteobacteria' and formed two distinct clusters, designated LKC group I and LKC group II, within this class. Group I was closely related to uncultured environmental clones from petroleum-contaminated groundwater, sulfidic springs, and sulfidic caves (97 to 99% sequence similarity), while group II formed a novel clade moderately related to deep-sea hydrothermal vent symbionts (90 to 94% sequence similarity). FISH with newly designed probes for both groups specifically stained filamentous bacteria within the mats. FISH-based quantification of the two filament groups in six different microbial mat samples from Lower Kane Cave showed that LKC group II dominated five of the six mat communities. This study further expands our perceptions of the diversity and geographic distribution of 'Epsilonproteobacteria' in extreme environments and demonstrates their biogeochemical importance in subterranean ecosystems

Diverse microbial communities inhabiting ferromanganese deposits in Lechuguilla and Spider Caves, 2003,
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Northup D. E. , Barns S. M. , Yu L. E. , Spilde M. N. , Schelble R. T. , Dano K. E. , Crossey L. J. , Connolly C. A. , Boston P. J. , Natvig D. O. , Dahm C. N. ,
Lechuguilla Cave is an ancient, deep, oligotrophic subterranean environment that contains an abundance of low-density ferromanganese deposits, the origin of which is uncertain. To assess the possibility that biotic factors may be involved in the production of these deposits and to investigate the nature of the microbial community in these materials, we carried out culture-independent, small subunit ribosomal RNA (SSU rRNA) sequence-based studies from two sites and from manganese and iron enrichment cultures inoculated with ferromanganese deposits from Lechuguilla and Spider Caves. Sequence analysis showed the presence of some organisms whose closest relatives are known iron- and manganese-oxidizing/reducing bacteria, including Hyphomicrobium, Pedomicrobium, Leptospirillum, Stenotrophomonas and Pantoea. The dominant clone types in one site grouped with mesophilic Archaea in both the Crenarchaeota and Euryarchaeota. The second site was dominated almost entirely by lactobacilli. Other clone sequences were most closely related to those of nitrite-oxidizing bacteria, nitrogen-fixing bacteria, actinomycetes and beta- and gamma-Proteobacteria. Geochemical analyses showed a fourfold enrichment of oxidized iron and manganese from bedrock to darkest ferromanganese deposits. These data support our hypothesis that microorganisms may contribute to the formation of manganese and iron oxide-rich deposits and a diverse microbial community is present in these unusual secondary mineral formations

Bacterial diversity and ecosystem function of filamentous microbial mats from aphotic (cave) sulfidic springs dominated by chemolithoautotrophic 'Epsilonproteobacteria', 2004,
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Engel As, Porter Ml, Stern La, Quinlan S, Bennett Pc,
Filamentous microbial mats from three aphotic sulfidic springs in Lower Kane Cave. Wyoming. were assessed with regard to bacterial diversity, community structure, and ecosystem function using a 16S rDNA-based phylogenetic approach combined with elemental content and stable carbon isotope ratio analyses. The most prevalent mat morphotype consisted of while filament bundles, with low C:N ratios (3.5-5.4) and high sulfur content (16.1-51.2%). White filament bundles and two other mat morphotypes organic carbon isotope values (mean delta(13)C = -34.7parts per thousand: 1sigma = 3.6) consistent with chemolithoautotrophic carbon fixation from a dissolved inorganic carbon reservoir (cave water, mean delta(13)C = -7.47parts per thousand for two springs, n = 8). Bacterial diversity was as low overall in the clone libraries, and the most abundant taxonomic group was affiliated with the 'Epsilonproteobacteria' (68%) with other bacterial sequences affiliated with Gammaproteobacteria (12.2%), Betaproteobacteria (11.7%), Deltaproteobacteria (0.8%), and the Acidobacterium (5.6%) and Bacteriodetes/Chlorobi (1.7%) divisions. Six distinct epsilonproteobacterial taxonomic groups were identified from the microbial mats. Epsilonproteobacterial and bacterial group abundances and community structure shifted front the spring orifices downstream. corresponding to changes in dissolved sulfide and oxygen concentrations and metabolic requirements of certain bacterial groups. Most of the clone sequences for epsilonproteobacterial groups were retrieved from areas with high sulfide and low oxygen concentrations, whereas Thiothrix spp. and Thiobacillus spp. had higher retrieved clone abundances where conditions of low sulfide and high oxygen concentrations were measured. Genetic and metabolic diversity among the 'Epsilonproteobacteria' maximizes overall cave ecosystem function, and these organisms play a significant role in providing chemolithoautotrophic energy to the otherwise nutrient-poor cave habitat. Our results demonstrate that sulfur cycling supports subsurface ecosystem through chemolithoautotrophy and expand the evolutionary and ecological views of 'Epsilonproteobacteria' in terrestrial habitats. (C) 2004 Federation of European Microbiological Societies. Published by Elsevier BY. All rights reserved

Microbial contributions to cave formation: New insights into sulfuric acid speleogenesis, 2004,
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Engel As, Stern La, Bennett Pc,
The sulfuric acid speleogenesis (SAS) model was introduced in the early 1970s from observations of Lower Kane Cave, Wyoming, and was proposed as a cave-enlargement process due to primarily H2S autoxidation to sulfuric acid and subaerial replacement of carbonate by gypsum. Here we present a reexamination of the SAS type locality in which we make use of uniquely applied geochemical and microbiological methods. Little H2S escapes to the cave atmosphere, or is lost by abiotic autoxidation, and instead the primary H2S loss mechanism is by subaqueous sulfur-oxidizing bacterial communities that consume H2S. Filamentous 'Epsilonproteobacteria' and Gammaproteobacteria, characterized by fluorescence in situ hybridization, colonize carbonate surfaces and generate sulfuric acid as a metabolic byproduct. The bacteria focus carbonate dissolution by locally depressing pH, compared to bulk cave waters near equilibrium or slightly supersaturated with calcite. These findings show that SAS occurs in subaqueous environments and potentially at much greater phreatic depths in carbonate aquifers, thereby offering new insights into the microbial roles in subsurface karstification

Involvement of microorganisms in the formation of carbonate speleothems in the Cervo Cave (L'Aquila-Italy), 2004,
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Cacchio P, Contento R, Ercole C, Cappuccio G, Martinez Mp, Lepidi A,
Much is known about the bacterial precipitation of carbonate rocks, but comparatively little is known about the involvement of microbes in the formation of secondary mineral structures in caves. We hypothesized that bacteria isolated from calcareous stalactites, which are able to mediate CaCO3 precipitation in vitro, play a role in the formation of carbonate speleothems. We collected numerous cultivable calcifying bacteria from calcareous speleothems from Cervo cave, implying that their presence was not occasional. The relative abundance of calcifying bacteria among total cultivable microflora was found to be related to the calcifying activity in the stalactites. We also determined the delta(13)C and delta(18)O values of the Cervo cave speleothems from which bacteria were isolated and of the carbonates obtained in vitro to determine whether bacteria were indeed involved in the formation of secondary mineral structures. We identified three groups of biological carbonates produced in vitro at 11degreesC on the basis of their carbon isotopic composition: carbonates with delta(13)C values ( a) slightly more positive, (b) more negative, and (c) much more negative than those of the stalactite carbonates. The carbonates belonging to the first group, characterized by the most similar delta(13)C values to stalactites, were produced by the most abundant strains. Most of calcifying isolates belonged to the genus Kocuria. Scanning electron microscopy showed that dominant morphologies of the bioliths were sherulithic with fibrous radiated interiors. We suggest a mechanism of carbonate crystal formation by bacteria

The Geomicrobiology of Ore Deposits, 2005,
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Southam G. , Saunders James A. ,
Bacterial metabolism, involving redox reactions with carbon, sulfur, and metals, appears to have been important since the dawn of life on Earth. In the Archean, anaerobic bacteria thrived before the Proterozoic oxidation of the atmosphere and the oceans, and these organisms continue to prosper in niches removed from molecular oxygen. Both aerobes and anaerobes have profound effects on the geochemistry of dissolved metals and metal-bearing minerals. Aerobes can oxidize dissolved metals and reduced sulfur, as well as sulfur and metals in sulfide minerals can contribute to the supergene enrichment of sulfide ores, and can catalyze the formation of acid mine drainage. Heterotrophic anaerobes, which require organic carbon for their metabolism, catalyze a number of thermodynamically favorable reactions such as Fe-Mn oxyhydroxide reductive dissolution (and the release of sorbed metals to solution) and sulfate reduction. Bacterial sulfate reduction to H2S can be very rapid if reactive organic carbon is present and can lead to precipitation of metal sulfides and perhaps increase the solubility of elements such as silver, gold, and arsenic that form stable Me-H2S aqueous complexes. Similarly, the bacterial degradation of complex organic compounds such as cellulose and hemicellulose to simpler molecules, such as acetate, oxalate, and citrate, can enhance metal solubility by forming Me organic complexes and cause dissolution of silicate minerals. Bacterially induced mineralization is being used for the bioremediation of metal-contaminated environments. Through similar processes, bacteria may have been important contributors in some sedimentary ore-forming environments and could be important along the low-temperature edges of high-temperature systems such as those that form volcanogenic massive sulfides

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