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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 accelerated corrosion is a localized concentration of solution intensity, produced by factors favoring greater aggressivity of the water in certain parts of the karstland creating differential solution rates and thereby a marked unevenness in the overall erosion of the karstland [19]. see also corrosion; alluvial corrosion.?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
See all featured articles
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 acids (Keyword) returned 33 results for the whole karstbase:
Showing 16 to 30 of 33
Karst development on carbonate islands, 2003, Mylroie J. E. , Carew J. L.

Karst development on carbonate platforms occurs continuously on emergent portions of the platform. Surficial karst processes produce an irregular pitted and etched surface, or epikarst. The karst surface becomes mantled with soil, which may eventually result in the production of a resistant micritic paleosol. The epikarst transmits surface water into vadose pit caves, which in turn deliver their water to a diffuse-flow aquifer. These pit caves form within a 100,000 yr time frame. On islands with a relatively thin carbonate cover over insoluble rock, vadose flow perched at the contact of carbonate rock with insoluble rock results in the lateral growth of vadose voids along the contact, creating large collapse chambers that may later stope to the surface.
Carbonate islands record successive sequences of paleosols (platform emergence) and carbonate sedimentation (platform submergence). The appropriate interpretation of paleosols as past exposure surfaces is difficult, because carbonate deposition is not distributed uniformly, paleosol material is commonly transported into vadose and phreatic voids at depth, and micritized horizons similar in appearance to paleosols can develop within existing carbonates.
On carbonate islands, large dissolution voids called flank margin caves form preferentially in the discharging margin of the freshwater lens from the effects that result from fresh-water/salt-water mixing. Similarly, smaller dissolution voids also develop at the top of the lens where vadose and phreatic fresh-waters mix. Independent of fluid mixing, oxidation of organic carbon and oxidation/reduction reactions involving sulfur can produce acids that play an important role in phreatic dissolution. This enhanced dissolution can produce caves in fresh-water lenses of very small size in less than 15,000 yr. Because dissolution voids develop at discrete horizons, they provide evidence of past sea-level positions. The glacio-eustatic sea-level changes of the Quaternary have overprinted the dissolutional record of many carbonate islands with multiple episodes of vadose, fresh-water phreatic, mixing zone, and marine phreatic conditions. This record is further complicated by collapse of caves, which produces upwardly prograding voids whose current position does not correlate with past sea level positions.
The location and type of porosity development on emergent carbonate platforms depends on the degree of platform exposure, climate, carbonate lithology, and rate of sea-level change. Slow, steady, partial transgression or regression will result in migration of the site of phreatic void production as the fresh-water lens changes elevation and moves laterally in response to sea-level change. The result can be a continuum of voids that may later lead to development solution-collapse breccias over an extended area.


Contaminant transport in karst aquifers, 2003, Vesper D. J. , Loop C. M. , White W. B.

Contaminants are easily injected into karst aquifers through sinking streams, sinkholes, or through open fractures and shafts in the carbonate rock. Transport of the contaminants through the aquifer is by a variety of mechanisms depending on the physical and chemical properties of the contaminant. Contaminants consist of (1) water soluble compounds, both organic and inorganic, (2) slightly soluble organic compounds, less dense than water (LNAPLs), (3) slightly soluble organic compounds, more dense than water (DNAPLs), (4) pathogens, (5) metals, and (6) trash. Water soluble compounds (e.g. nitrates, cyanides, carboxylic acids, phenols) move with the water. But rather than forming a plume spreading from the input point, the contaminated water forms linear stringers migrating down the conduit system toward the discharge point. LNAPLs (e.g. petroleum hydrocarbons) float on the water table and can migrate down the water table gradient to cave streams where they tend to pond behind obstructions. DNAPLs (e.g. chlorinated hydrocarbons), in contrast, sink to the bottom of the aquifer. In the conduit system, DNAPLs pond in low spots at the bottom of the conduit and infiltrate sediment piles. Transport of both LNAPL and DNAPL is dependent on storm flow which can force LNAPL through the system as plug flow and can move DNAPLs by mobilizing the sediment piles. Pathogens (viruses, bacteria, parasites) are transported through the karstic drainage system because of the absence of filtration and retain their activity for long distances. Metals (e.g. chromium, nickel, cadmium, mercury, and lead) tend to precipitate as hydroxides and carbonates in the neutral pH, carbonate rich water of the karst aquifer. Metal transport is mainly as particulates and as metal adsorbed onto small particulates such as clays and colloids. Metal transport is also episodic. Metals migrate down the flow path under flow conditions that take small particulates into suspension. Trash is carried into karst aquifers through sinkholes and sinking streams. It is, in effect, a form of clastic sediment, and can be carried deep into the conduit system where it can act as a source term for other contaminants leached from the trash


The early Ordovician Majiagou reservoir of the Jingbian Field, northwest China: Karstic peritidal dolomite, 2004, Zhang W. H. ,
The Jingbian Field is located in the central part of the Ordos Basin in the west part of the North China Platform. It is the largest gas field discovery in China in the 1980's. The field is an example of production from a paleogeomorphic trap formed by karstification of Lower Ordovician peritidal dolomites. In terms of gas potential, the Majiagou Formation is the more important stratigraphic unit. It is composed of six members, the uppermost member (O(1)m(6)) has been largely removed by prolonged Caledonian karst erosion, leaving the underlying (O(1)m(5)) member to provide the main pay for the field. In spite of the 163 wells drilled the field presents many problems and uncertainties because of the poor seismic definition of the pay zones and the great reservoir heterogeneity of the karst system. Statistical data from more than 30 wells show a poor correlation between individual well-flow rates and thickness of the karstic zone or distance of wells, relative to a paleochannel. This suggests karstification is not the most important factor controlling productivity. The release of organic acids (during maturation of the source rock) and fracturing in response to Cretaceous tectonic event appear to be key factors responsible for the productivity of the Majiagou-5 (O(1)m(5)) reservoir in terms of modifying and enlarging the pore network. Carboniferous clays provide an effective updip seal through the infill of karst-breccia zones. High productivity is prominent along structural axes where karstic fractures, solution vugs and caverns are interconnected by vertical to sub-vertical fractures. On the basis of pore-type the Majiagou-5 Member reservoirs can be divided into four reservoir types, each allowing differentiation of reservoir quality through characteristic porosity-permeability ranges and capillary-pressure curves. Key aspects which affect the commerciality of the field are still uncertain but with recent test wells producing gas with water, considerations should focus on the mechanism of weak edge-water drive and the need to predict fracture zones

Study of soil leachates in doline above the Beke Cave, Hungary, 2004, Tatar E. , Mihucz V. G. , Tompa K. , Poppl L. , Zaray G. , Zambo L. ,
Fulvic acid, Ca and Mg concentrations as well as dissolved inorganic carbon (DIC), pH and electric conductivity values of soil solutions which resulted from injecting bidistilled water onto glass columns filled with different soils (black rendzina, brown rendzina, red clayey rendzina, red clay) characteristic of the Aggtelek karst system (NE Hungary), were determined. Identification and determination of fulvic acid were achieved by size exclusion chromatography (SEC) and adsorption chromatography, respectively, with fluorescent spectrometric detection. The Ca and Mg concentration of the samples was determined by applying an inductively coupled plasma atomic emission spectrometric (ICP-AES) method. DIC-expressed in CO2 concentration values-was determined by using a CO2 selective electrode. According to the SEC analysis, the apparent molecular weight of the fulvic acids of the samples were between 500 and 1600 Da. The fulvic acid concentration values of the percolated water samples decreased in function of the soils investigated as follows: black rendzina>brown rendzina>red clayey rendzina>red clay, which is in concordance with the organic matter content of these types of soils. The results obtained for fulvic acid, Ca and Mg concentrations as well as for DIC, pH and electric conductivity of the water samples collected from the column filled with red clay were in good agreement with those of a seepage water sample collected from an observation station built in red clay above the Beke Cave (Aggtelek). Since the artificially prepared red clay column was exposed to the same temperature and humidity conditions like red clay of the sampling site, this method seems to be suitable for modelling infiltration of fulvic acid and metals from red clay into seepage water under laboratory conditions. (C) 2003 Elsevier B.V. All rights reserved

Rapid biotic molecular transformation of fulvic acids in a karst aquifer, 2007, Einsiedla Florian , Hertkornb Norbert, Wolfa Manfred, Frommbergerb Moritz, Schmittkopplinb Philippe, Kochc Boris P.

Textural, Elemental, and Isotopic Characteristics of Pleistocene Phreatic Cave Deposits (Jabal Madar, Oman), 2007, Immenhauser Adrian, Dublyansky Yuri V. , Verwer Klaas, Fleitman Dominik, Pashenko Serguei E. ,
Two main types of karst formation are commonly known: the surficial meteoric one and the subsurface (hypogenic) karst, which can be related to both carbonic (H2CO3) and sulfuric (H2S) acids. This paper documents evidence for a third, CO2-regime related, type of karst that is less commonly described. Petrographic and geochemical properties of exhumed Pleistocene phreatic cave deposits from the diapiric Jabal Madar dome in northern Oman are documented and discussed in a process-oriented context. These calcites form at the interface between two fundamentally different diagenetic and hydrogeological domains: the deep-seated, hydrothermal and the near-surficial, meteoric-vadose one. Four calcite phases are recognized: (i) acicular, (ii) blocky to stubby elongated, (iii) proto-palisade, and (iv) macro-columnar calcites. The macro-columnar calcites, forming the last stage of precipitation, are conspicuous due to their cyclical red zonation, and they form the main (geochemical) focus of this study. Fluid inclusion data point to fluid temperatures of between 30 to 50{degrees}C (monophase liquid inclusions) and elevated salinities (1.6 to 7.3 wt.% NaCl equivalent). Low carbon-isotope data (-8 to -9{per thousand}) are in agreement with the influx of soil-zone CO2 whereas decreasing {delta}18O (-15{per thousand}) values might point to mixing of saline hydrothermal and 18O depleted, meteoric freshwater, i.e., two fluid sources. Trace-element and stable-isotope data shift between the different cement phases and vary cyclically across the red zoning in macro-columnar calcites. With respect to the intra-crystal variability, these patterns are perhaps best explained in the context of redox potential. Two interpretations are presented; the one favored here suggests that the cyclical red zoning in macro-columnar calcites is controlled by Pleistocene monsoonal climate patterns

Cave Geology, 2007, Palmer A. N.
Cave Geology is the definitive book on the subject by an internationally recognized authority. It can be easily understood by non-scientists but also covers a wide range of topics in enough detail to be used by advanced researchers. Illustrated with more than 500 black-and-white photographs and 250 diagrams and maps, this book is dedicated to anyone with an interest in caves and their origin. Topics include: CONTENTS Preface 1 Speleology the science of caves Cave types Cave exploring Nationwide speleological organizations Searching for caves Cave mapping Preparation of a cave map Cave science Underground photography Show caves Cave preservation and stewardship 2 Cave country Geologic time Landscape development Surface karst features Paleoleokarst Pseudokarst The scale of karst features Distribution of karst and caves The longest and deepest known caves 3 Cavernous rocks Rock types Soils and sediments Stratigraphy Highly soluble rocks Rock structure Rock and mineral analysis A brief guide to rock identification 4 Underground water in karst Types of underground water Vadose flow patterns Phreatic flow patterns Aquifers Nature of the karst water table The freshwater-seawater interface Groundwater hydraulics Flow measurements Use of flow equations in cave interpretation Measuring the flow of springs and streams Groundwater tracing Interpreting groundwater character from tracer tests and flood pulses Quantitative dye tracing 5 Chemistry of karst water Simple dissolution Dissoltion of limestone and dolomite How much rock has dissolved? pH Undersaturation and supersaturation Epigenic and hypogenic acids Chemical interactions Dissolution rates Dissolution of poorly soluble rocks Microbial effects on chemistry Isotopes and their use Analysis of spring chemistry A chemical cave tour Chemical field studies 6 Characteristics of solution caves Cave entrances Passage types Passage terminations Cave rooms Cave levels Cave patterns Minor solution features in caves Interpreting flow from scallops Cave sediments Bedrock collapse Cave biology 7 Speleogenesis: the origin of caves Basic concepts Development of ideas about cave origin Comprehensive views of cave origin Rates of cave enlargement Insight from computer modeling Life cycle of a solution cave 8 Control of cave patterns by groundwater recharge Sinkhole recharge: branchwork caves The problem of maze caves Floodwater caves Caves formed by diffuse flow Hypogenic caves Polygenetic caves Influence of climate 9 Influence of geology on cave patterns Distribution of soluble rocks Influence of rock type Influence of geologic structure Relation of caves to landscape evolution A guide to cave patterns 10 Cave minerals Origin and growth of cave minerals Origin of common cave minerals Speleothem types Speleothem growth rates Speleothem decay 11 Caves in volcanic rocks Volcanic processes and landscapes Types of lava caves Origin and character of lava-tube caves Speleogens and speleothems in lava caves Time scale of lava caves 12 Cave meteorology and internal weathering Composition of cave air Cave temperatures Air movement Evaporation and condensation Weathering in the cave atmosphere Chemical zones in air-filled caves 13 Caves and time Relative and numerical ages Determining cave ages Studies of past climates Caves through the ages 14 Geologic studies of caves Field mapping Calibrating survey instruments Geologic interpretions Testing interpretations for validity Detailed analysis of a cave Further goals 15 Application of cave geology to other geosciences The problem of sampling bias Water supply Engineering applications Land management Interpretation of geologic processes Petroleum geology Mining Scientific frontiers The limits of discovery Glossary References Index Conversion between U.S. and metric units

Phreatic cave calcites - archives of two realms, 2009, Immenhauser, Adrian

Two main types of karst formation are commonly known: the surficial meteoric one and the subsurface (hypogenic) karst, related to both carbonic (H2CO3) and sulphuric (H2S) acids. Nevertheless, a third, less well studied type exists that is referred to here as CO2-regime related karst. This article describes Pleistocene phreatic cave spar from the diapiric Jabal Madar dome in Northern Oman. These caverns and their precipitates probably represent examples of CO2-related karsting and subsequent calcite precipitation. Phreatic calcites form at the interface between two fundamentally different diagenetic and hydrogeological domains: the deep-seated, hydrothermal and the near-surficial, meteoric-vadose one. Changes in the ratio between hydrothermal upwelling and meteoric influx are recorded in the geochemistry and mineralogy of these calcites making them uncommon archives of two contrasting realms.


HYDROGEOLOGICAL FUNCTIONING OF A KARST AQUIFER DEDUCED FROM HYDROCHEMICAL COMPONENTS AND NATURAL ORGANIC TRACERS PRESENT IN SPRING WATERS. THE CASE OF YEDRA SPRING (SOUTHERN SPAIN), 2010, Mudarra M. , Andreo B.
The major chemical parameters, TOC and natural fluorescence of yedra spring, Malaga province, southern Spain were monitored from April 2008 to March 2009. The electrical conductivity and the concentrations of most major ions decreased following recharge periods. The TOC and NO3, representing tracers from the soil that infiltrate through the unsaturated zone, were found to vary inversely with the Mg2+ content, which is a natural indicator of groundwater residence time. Furthermore, a strong, direct relation was found between TOC and the natural fluorescence associated with humic and fulvic acids. Both parameters respond similarly to rainfall events, exhibiting significant increases during recharge followed by reductions during recession. This relation means that TOC mainly originates from organic acids. The results document rapid infiltration processes with a lag of less than one day following rainfall, which is typical of a karst aquifer with conduit flow, rapid drainage and limited natural regulation. The combined use of conventional hydrochemical parameters and natural organic tracers facilitates aquifer characterization and validates the vulnerability to contamination.

Impact of chlorides, nitrates, sulfates and phosphates on increased limestone dissolution in the karst vadose zone (Postojna Cave, Slovenia) , 2011, Kogovek, Janja

Distinctive karst hydrology arises from a combination of high carbonate rock solubility and well developed secondary porosity
(fissures). Soil CO2 is the most important influence on solubility
of carbonate rock (Ford & Williams 2007). Human activity
on the karst surface results in pollution that has an important influence on water quality. Degradation of organic pollution (e.g. waste water, leachates from landfill sites) results in inorganic
acids too. These acids could have an important additional influence on dissolution of carbonate rocks in the vadose zone. In the framework of more than 20 years of research on precipitation
percolation and transfer of contaminants (direct outflow of waste water from a small military facility where about twenty troops were stationed) through the 100-m thick vadose zone of Postojna Cave, contaminated water was observed in drips and trickles in the cave (up to 60 mg Cl-/l, up to 180 mg NO3-/l, up to 2.8 mg PO43-/l, and up to 50 mg SO42-/l). At the same time the sum of calcium and magnesium (Ca+Mg) of trickles was up to two times larger than the Ca+Mg of either the uncontaminated
reference trickle or the input waste water. The amount of dissolved limestone carried by waste water to trickles and drips in the cave was directly proportional to the concentration
of contaminant anions present. This demonstrates that there is an accelerated widening of fissures below source points of wastewater. Water with contaminants can penetrate faster and deeper into the vadose zone along the increasingly permeable
fissures without losing its dissolving power, and thus significant dissolution occurs ever deeper in the vadose zone. This results in ever faster penetration of contaminants through the vadose zone. In the final phase of such development, which takes many decades or longer, relatively rapid transfer of contaminants
through the aquifer all the way to karst springs with minimal self-cleansing effects can be expected.


Organic matter of fossil origin in the amberine speleothems from El Soplao Cave (Cantabria, Northern Spain), 2012, Gzquez Fernando, Jose Maria Calaforra, Fernando Rull, Paolo Forti, And Antonio Garcacasco.

Unusual amberine-coloured speleothems were recently found in El Soplao Cave (Cantabria, Spain). Chromophore elements such as Fe, Mn, Cd, Co or Ti were not present in significant quantities. Rather, our data show that their colour comes from leachates of fossilized organic material hosted in the carbonaceous Urgonian facies of the host rock. These leachates are related to the Cretaceous amber deposit that has been recently discovered in the vicinity of El Soplao Cave. The presence of humic and fulvic acids of fossil origin were confirmed by IR and Raman spectroscopic analysis of the carbonaceous strata and the speleothems. In addition, the mineralogy of the amberine speleothems was studied. Alternating bands made of calcite and aragonite reveal that periods of humidity and aridity occurred within the cave during the speleothem genesis.


Radionuclides as natural tracers for the characterization of fluids in regional discharge areas, Buda Thermal Karst, Hungary, 2012, Eross A. , Mdlszonyi J. , Surbeck H. , Horvth . , Goldscheider N. , Csoma A. .

The Buda Thermal Karst (Budapest, Hungary) developed in the regional discharge zone of a carbonate rock aquifer system. High radioactivity of the spring waters has already been reported in 1912, but there has been no detailed study and no consistent explanation for its origin. In this area mixing of cold and hot karst waters was hitherto assigned to be responsible for cave formation. However, the dissimilarity of the discharging waters within Budapest (in the North: Rozsadomb; in the South: Gellert Hill), may suggest also different cave forming processes. The application of radionuclides as natural tracers represents a novel approach to investigate these questions. For this study, we used uranium, radium and radon to identify mixing of fluids in the Buda Thermal Karst system and to infer the temperature and chemical composition of the end members. Chloride as a conservative component allowed the mixing ratios for the sampled waters to be calculated. Their fluid compositions were modeled and through the comparison of modeled and measured values, the end members were validated. As the result of this study, it was possible to characterize the mixing end members for the Rozsadomb area, whereas for the Gellert Hill discharge zone, mixing components could not be identified with the aid of radionuclides. Therefore, it is suggested that different processes are responsible for cave formation in these areas. In the Rozsadomb area, structurally-controlled mixing is the dominant cave forming process, whereas in the Gellert Hill area, due to the lack of mixing members, other processes have to be found, which are responsible for the formation of the caves, such as retrograde calcite solubility and/or geogenic acids, such as H2S. The application of radionuclides thus further supported the differences between the two study areas. This study identified moreover the source of elevated radon content of the waters in the Gellert Hill area in form of iron-hydroxide precipitates that accumulate in the spring caves. These precipitates are highly efficient in adsorbing radium, which generates radon by alpha decay, and hence act as local radon source for the waters. In this study we showed that uranium, radium and radon naturally occurring in groundwater can be used to characterize fluids of different flow systems in regional discharge areas owing to the contrasting geochemical behaviors of these elements


Microbiological Activities in Moonmilk Monitored Using Isothermal Microcalorimetry (Cave of Vers Chez Le Brandt, Neuchatel, Switzerland), 2012, Braissant O. , Binderschedler S. , Daniels A. U. , Verrecchia E. P. , Cailleau G.

 

Studies of the influence of microbial communities on calcium carbonate deposits mostly rely on classical or molecular microbiology, isotopic analyses, and microscopy. Using these techniques, it is difficult to infer microbial activities in such deposits. In this context, we used isothermal microcalorimetry, a sensitive and nondestructive tool, to measure microbial activities associated with moonmilk ex-situ. Upon the addition of diluted LB medium and other carbon sources to fresh moonmilk samples, we estimated the number of colony forming units per gram of moonmilk to be 4.8 3 105 6 0.2 3 105. This number was close to the classical plate counts, but one cannot assume that all active cells producing metabolic heat were culturable. Using a similar approach, we estimated the overall growth rate and generation time of the microbial community associated with the moonmilk upon addition of various carbon sources. The range of apparent growth rates of the chemoheterotrophic microbial community observed was between 0.025 and 0.067 h21 and generation times were between 10 and 27 hours. The highest growth rates were observed for citrate and diluted LB medium, while the highest carbon-source consumption rates were observed for low molecular weight organic acids (oxalate and acetate) and glycerol. Considering the rapid degradation of organic acids, glucose, and other carbon sources observed in the moonmilk, it is obvious that upon addition of nutrients during snow melting or rainfall these communities can have high overall activities comparable to those observed in some soils. Such communities can influence the physico-chemical conditions and participate directly or indirectly to the formation of moonmilk.


Zur Mikrobiologie von Bergmilch, 2012, Reitschuler C. , Schwarzenauer T. Lins P. , Wagner A. O. , Sptl C. , Illmer P.
Moonmilk is a plastic mineral formation, which can be found inside cave systems all around the world. These deposits mainly consist of microscopic calcite crystals and show a very high water content. However, the association of microorganisms is remarkable, which seem to play a crucial role in the formation process. The present study applies a combination of culture-based methods and DNA analysis and is to our knowledge the first attempt to investigate this phenomenon in an Alpine cave, in Austria. Central questions include (i) the origin of the occurring microorganisms, (ii) their supply with energy and nutrients, (iii) their role in course of the formation of the deposits, and (iv) their structure and organization. The investigations within the Hundalm Eis- und Tropfsteinhhle in Tyrol revealed that a complex, heterotroph-dominated, psychrophilic microbial com munity, con - sisting of archaea, bacteria and fungi is associated with moonmilk, with partly high microbial abundances. Via living cultivation microorganisms could be proved in all 29 samples, with individual (bacterial) numbers of up to one million per ml moonmilk. The remarkable number of pigmented species could be an indication for the origin from a light-exposed surficial habitat. Molecular biological methods proved that even more organisms inhabit this habitat as was suggested after the culture-based investigations. One million archaea per ml were detected in some samples. The detection of different organic acids partially in appreciable amounts is an indication for biological activity and could also give a hint to the energy and nutrient inputin this system.

The cave environment inf luencing the lipid prof ile and hepatic lipogenesis of the f ish Ancistrus cryptophthalmus Reis, 1987 (Siluriformes: Loricariidae), 2013, Bastos V. A. A. , Lopes Ferreira R. , Carvalho D. C. , Pugedo M. L. , De Matos Alves Pinto L.

The metabolism of hypogean organisms is frequently molded by the cave environment traits, especially food scarcity. The aim of the present work was to evaluate the inf luence of such environment on lipid composition and hepatic lipogenesis in the f ish Ancistrus cryptophthalmus. For this, the species was compared to an epigean population of the species. A greater accumulation of total lipids was observed in the cave-dwelling f ish (18.36 g/100 g tissue) compared to the surface f ish (14.09 g/100 g tissue). The muscle fatty acid prof ile also varied between the populations. Arachidonic acid was only detected in the epigean f ish, while docosahexaenoic acid was present in the cave f ish. In the lipid prof ile of Ancistrus cryptophthalmus there was a higher proportion of saturated fatty acids, followed by monounsaturated and polyunsaturated fatty acids; Ancistrus sp. showed a predominance of monounsaturated fatty acids. Signif icant differences were also observed in the activities of the hepatic enzymes glucose-6-phosphate dehydrogenase and malic enzyme. The activities of these two enzymes were greater in the epigean animals. The differences could be related to different food availability observed in the two environments. An ecotone zone was observed, located next to the entrance of the Lapa do Angélica cave (Goiás State, Brazil), where the f ishes showed characteristics that were intermediate between those of hypogean f ishes from deeper within the cave, and the epigean population. It could be concluded that the characteristics of the cave environment signif icantly inf luenced the composition of muscle fatty acids and lipogenesis in the hypogean f ish Ancistrus cryptophthalmus.


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