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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. ...

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. ...

Speleology in Kazakhstan

Shakalov on 11 Jul, 2012
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 calcareous is 1. containing calcium carbonate [10]. 2. descriptive of a rock that contains calcium carbonate [9].?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
Engineering challenges in Karst, Stevanović, Zoran; Milanović, Petar
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Geochemical and mineralogical fingerprints to distinguish the exploited ferruginous mineralisations of Grotta della Monaca (Calabria, Italy), Dimuccio, L.A.; Rodrigues, N.; Larocca, F.; Pratas, J.; Amado, A.M.; Batista de Carvalho, L.A.
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
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Your search for fluorescence (Keyword) returned 33 results for the whole karstbase:
Showing 16 to 30 of 33
Seasonal changes of fulvic acid, Ca and Mg concentrations of water samples collected above and in the Beke Cave of the Aggtelek karst system (Hungary), 2004, Tatar Eniko, Mihucz Victor G. , Zambo Laszlo, Gasparics Tibor, Zaray Gyula,
Magnesium and Ca concentration ratios, fulvic acid content, total dissolved inorganic carbon (DIC) and pH were determined in seepage water and drip water samples collected during one seasonal cycle between June 2000 and May 2001 above and in the Beke Cave of Aggtelek (Hungary). Seepage water samples were collected at 0.5 and 7 m below ground level from an observation point situated above the cave. Drip water was collected 40 m underground from a group of stalactites. The fulvic acid concentrations were determined by fluorescence spectrometry after pre-concentration on a XAD-8 chromatographic column. Calcium and Mg concentrations were measured by inductively coupled plasma atomic-emission spectrometry. DIC was determined with a CO2 - selective electrode. DIC values increased and the fulvic acid concentrations and Mg and Ca concentration ratios, generally, decreased with depth. The highest flux of fulvic acid was observed in spring. The fulvic acid flux increased by a factor of 2.6-3.6 and 1.4 for groundwater and drip water, respectively, compared with those registered in the winter samples. The variations in the Ca, Mg and fulvic acid concentrations of the seepage and drip water samples relate to the variable drip rate. The results revealed that there is a strong correlation between the daily average surface temperature, daily amount of precipitation and drip water rate registered in the cave

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

Microbial contributions to cave formation: New insights into sulfuric acid speleogenesis, 2004, 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

Speleothem organic matter content imaging. The use of a Fluorescence Index to characterise the maximum emission wavelength, 2005, Perrette Y. , Delannoy J. J. , Desmet M. , Lignier V. , Destombes J. L. ,
The study of palacoenvironments, especially pedologic and biologic environments, is fundamental to a complete understanding of continental climate changes. Many types of sediment contain organic molecules (OM) that were trapped during the depositional process, with the quantity and the nature of these organic molecules being strongly influenced by climate and other local factors. The quantity of organic matter in sediment can be measured by fluorescence intensity, but its nature is more difficult to determine. For this research, the organic molecules in stalagmites were analysed using emission fluorescence spectroscopy. The analysis of carbonated karst sediments was complemented by studies of clay, soil and seepage water samples. The main objective of this paper is to describe a method for the continuous imaging of the spectroscopic features of stalagmite organic molecules. Continuous imaging provides a means of circumventing the nonlinearity, both in space (of the sediment) and in time (of the sedimentation process), of the trapping of organic matter. This methodological report presents a protocol for calculating a Fluorescence Index (FI) that can be used in palaeoenvironmental studies of sediment. A similar approach to that used for determining E4/E6 ratios was used to determine the ratio of the fluorescence intensities of a sample at 514 nm and at 456 nm. This Fluorescence Index is strongly correlated to the wavelength of the maximum intensity of the organic matter spectrum. Due to the relatively stable chemical environment of calcite growth, changes in the Fluorescence Index can be interpreted as being due to changes in the nature of the organic molecules rather than to pH or quenching effects. As an illustration of how this index can be used, we present some examples of fluorescence indices for speleothem samples that show short-term and long-term environmental changes. To allow fuller palaeoenvironmental interpretations to be made, fluorescence indices need to be calibrated to environments and samples need to be dated. (C) 2004 Elsevier B.V. All rights reserved

Utilising seasonal variations in hydrogeochemistry and excitation-emission fluorescence to develop a conceptual groundwater flow model with implications for subsidence hazards: an example from Co. Dur, 2005, Lamontblack J. , Baker A. , Younger P. L. , Cooper A. H. ,

Influence of hydrological and climatic parameters on spatial-temporal variability of fluorescence intensity and DOC of karst percolation waters in the Santana Cave System, Southeastern Brazil, 2005, Cruz J, Karmann I, Magdaleno Gb, Coichev N, Viana J,
Fluorescence intensity (FI) and organic carbon concentration of groundwater percolating through soil and rock into the Santana Cave were monitored at eight different cave sites between 2000 and 2002 to investigate their relationships to climatic parameters, stalactite discharge and thickness of rock overlying the cave. FI values, compared among sampling sites, are inversely proportional to depth and directly proportional to discharge; in contrast, dissolved organic matter (DOC) shows no significant spatial variability. Time-series analysis demonstrated similarities in DOC trends of different waters, but no correlation was observed with FI trends. Combined evaluation of DOC of infiltration waters, rainfall data and chemical parameters of Fe, O2, pH, Eh in soil solution indicate that peaks in DOC content coincide with more reduced conditions in the soil and have a lag time of 2-3 months after heavy showers. Variation of FI throughout the year occurs at all sampling sites but only higher drip discharge and rimstone pool waters were correlatable to rainfall events. FI of lower discharge sampling sites shows similar trends, but no relationship between drip discharge and rainfall variation was observed. Ranges and means of FI for all drip waters were significantly higher in the 2001-2002 period than in the preceding 2000-2001 period, which correlates with a 5.5 [deg]C increase in mean austral winter temperatures in 2001. Hence, FI variations of karst waters that form carbonate speleothems under a humid subtropical climate may provide a useful proxy in paleoenvironmental reconstruction

Error and Technique in Fluorescent dye Tracing, 2005, Smart Chris

The appropriate approach to dye tracing in karst areas depends upon the objective and context of the trace. Dye tracing in karst areas is undertaken to address geographical, hydrogeological and contaminant problems at particular spatial and temporal resolution in the context of prior knowledge, available resources, social and legal expectations and environmental constraints. The value of a trace is improved if the objective can be formalized into a rational hypothesis and where the signal is demonstrably distinct from error. This requires sampling and analysis as much to define error as to detect the signal. The tolerable error depends on the dye trace objective and context, and scales with the sophistication of both, becoming increasingly critical and challenging as higher level interpretations are made. The appropriate technique for a particular trace therefore depends not only on the problem and context, but also upon the necessity of defining and correcting errors. Simpler problems such as establishment of underground connections can often be usefully tackled with simple techniques. Variable background fluorescence is a particularly difficult systematic error in dye tracing that can be reduced by supplementary sampling and control. This approach is illustrated for fluorescence spectra and in situ filter fluorometry. To extract a signal from spectra a statistical correction has been developed allowing compositional and concentration corrections to highlight anomalous samples. Supplementary sampling is required to provide the background statistics necessary for such an approach. The strong spectral coherence of background allows concurrent green fluorescence measurements to define variable background fluorescence during a red dye trace. The relationship between red and green fluorescence in un-dyed samples can be used to model background behavior in the presence of the red dye.


Dominant Microbial Populations in Limestone-Corroding Stream Biofilms, Frasassi Cave System, Italy, 2006, Macalady Jennifer L. , Lyon Ezra H. , Koffman Bess, Albertson Lindsey K. , Meyer Katja, Galdenzi Sandro, Mariani Sandro,
Waters from an extensive sulfide-rich aquifer emerge in the Frasassi cave system, where they mix with oxygen-rich percolating water and cave air over a large surface area. The actively forming cave complex hosts a microbial community, including conspicuous white biofilms coating surfaces in cave streams, that is isolated from surface sources of C and N. Two distinct biofilm morphologies were observed in the streams over a 4-year period. Bacterial 16S rDNA libraries were constructed from samples of each biofilm type collected from Grotta Sulfurea in 2002. {beta}-, {gamma}-, {delta}-, and {varepsilon}-proteobacteria in sulfur-cycling clades accounted for [≥]75% of clones in both biofilms. Sulfate-reducing and sulfur-disproportionating {delta}-proteobacterial sequences in the clone libraries were abundant and diverse (34% of phylotypes). Biofilm samples of both types were later collected at the same location and at an additional sample site in Ramo Sulfureo and examined, using fluorescence in situ hybridization (FISH). The biomass of all six stream biofilms was dominated by filamentous {gamma}-proteobacteria with Beggiatoa-like and/or Thiothrix-like cells containing abundant sulfur inclusions. The biomass of {varepsilon}-proteobacteria detected using FISH was consistently small, ranging from 0 to less than 15% of the total biomass. Our results suggest that S cycling within the stream biofilms is an important feature of the cave biogeochemistry. Such cycling represents positive biological feedback to sulfuric acid speleogenesis and related processes that create subsurface porosity in carbonate rocks

Late Holocene drought responsible for the collapse of Old World civilizations is recorded in an Italian cave flowstone, 2006, Drysdale R, Zanchetta G, Hellstrom J, Maas R, Fallick A, Pickett M, Cartwright I, Piccini L,
A severe drought in parts of low-latitude northeastern Africa and southwestern Asia [~]4200 yr ago caused major disruption to ancient civilizations. Stable isotope, trace element, and organic fluorescence data from a calcite flowstone collected from the well-watered Alpi Apuane karst of central-western Italy indicate that the climatic event responsible for this drought was also recorded in mid-latitude Europe. Although the timing of this event coincides with an episode of increased ice-rafted debris to the subpolar North Atlantic, the regional ocean-atmosphere response seems atypical of similar Holocene ice-rafting events. Furthermore, comparison of the flowstone data with other regional proxies suggests that the most extreme part of the dry spell occurred toward the end of a longer-term climate anomaly

Modelling of dripwater hydrology and hydrogeochemistry in a weakly karstified aquifer (Bath, UK): Implications for climate change studies, 2006, Fairchild Ij, Tuckwell Gw, Baker A, Tooth Af,
A better knowledge of dripwater hydrology in karst systems is needed to understand the palaeoclimate implications of temporal variations in Mg/Ca and Sr/Ca of calcareous cave deposits. Quantitative modelling of drip hydrology and hydrochemistry was undertaken at a disused limestone mine (Brown's Folly Mine) in SW England overlain by 15 m of poorly karstified Jurassic limestones, with sub-vertical fracturing enhanced by proximity to an escarpment. Discharge was monitored at 15 sites intermittently from the beginning of 1996, and every 10-20 days from later 1996 to early 1998. Samples for hydrochemical parameters (pH, alkalinity, cations, anions, fluorescence) were taken corresponding to a sub-set of these data and supplernented by bedrock and soil sampling, limited continuously logged discharge, and soil water observations. Three sites, covering the range of discharge (approximately 1 mu L s(-1) to 1 ml s(-1) maximum discharge) and hydrochemical behaviours, were studied in more detail. A quantitative flow model was constructed, based on two parallel unit hydrographs: responsive and relatively unresponsive to discharge events, respectively. The linear response and conservative mixing assumptions of the model were tested with hydrogeochemical data. Dripwaters at many of sites are characterized by evidence of prior calcite precipitation in the flowpath above the mine, which in the higher discharging sites diminishes at high flow. Also at low flow rates, dripwaters may access seepage reservoirs enriched in Mg and/or Sr, dependent on the site. The discharge at all three sites can be approximated by the flow model, but in each case, hydrochemical data show violations of the model assumptions. All sites show evidence of non-conservative mixing, and there are temporal discontinuities in behaviour, which may be stimulated by airlocks generated at low flow. Enhanced Mg/Ca and Sr/Ca often do relate to low-flow conditions, but the relationships between climate and hydrogeochemical response are non-linear. (c) 2005 Elsevier B.V. All rights reserved

Extremely acidic, pendulous cave wall biofilms from the Frasassi cave system, Italy, 2007, Jennifer L. Macalady, * Daniel S. Jones And Ezra H. Lyon
The sulfide-rich Frasassi cave system hosts an aphotic, subsurface microbial ecosystem including extremely acidic (pH 0?1), viscous biofilms (snottites) hanging from the cave walls. We investigated the diversity and population structure of snottites from three locations in the cave system using full cycle rRNA methods and culturing. The snottites were composed primarily of bacteria related to Acidithiobacillus species. Other populations present in the snottites included Thermoplasmata group archaea, bacteria related to Sulfobacillus, Acidimicrobium, and the proposed bacterial lineage TM6, protists, and filamentous fungi. Based on fluorescence in situ hybridization population counts, Acidithiobacillus are key members of the snottite communities, accompanied in some cases by smaller numbers of archaea related to Ferroplasma and other Thermoplasmata. Diversity estimates show that the Frasassi snottites are among the lowestdiversity natural microbial communities known, with one to six prokaryotic phylotypes observed depending on the sample. This study represents the first in-depth molecular survey of cave snottite microbial diversity and population structure, and contributes to understanding of rapid limestone dissolution and cave formation by microbially mediated sulfuric acid speleogenesis.

Variability in terrestrial and microbial contributions to dissolved organic matter fluorescence in the Edwards Aquifer, Central Texas, 2009, Birdwell J. E. And Engel A. S.
Most cave and karst ecosystems are believed to be dependent on an influx of allochthonous organic carbon. Although microbes are largely responsible for the fate of dissolved organic matter (DOM) in karst, the role of microbes in chemosynthetic (autochthonous) production and processing of DOM has received limited attention. Chromophoric dissolved organic matter (CDOM) is the fraction of DOM that absorbs ultraviolet and visible light, and differences in the fluorescence spectral characteristics of humic-like (terrigenous) and protein-like (microbially-derived) CDOM allow for tracing the relative contributions of allochthonous or autochthonous carbon sources, respectively, in water. We investigated CDOM in karst-aquifer well and spring waters along the fresh- to saline-water transition zone of the Edwards Aquifer, Central Texas, over a four year period. The groundwater fluorescence spectral characteristics were distinct from those generally observed in surface waters and soil porewaters. The dominant source of organic carbon in the aquifer waters may be a product of chemolithoautotrophic primary production occurring in situ. It is possible that the absence of a strong terrestrial CDOM signature may be due to filtering effects in the epikarst or rapid utilization by heterotrophs in the aquifer. Our results indicate that intense recharge following periods of drought may influence the intensity of microbial activity, either due to an influx of DOM or nutrients from the surface that was not quantified by our analyses or because of increased in situ autotrophic activity, or both. The variable contributions of allochthonous and autochthonous DOM during and after recharge events call into question whether karst aquifer ecosystems are necessarily dependent on allochthonous organic matter.

A recently evolved symbiosis between chemoautotrophic bacteria and a cave-dwelling amphipod, 2009, Dattagupta, S. , Schaperdoth, I. , Montanari, A. , Mariani, S. , Kita, N. , Valley, J. W. And Macalady, J. L.
Symbioses involving animals and chemoautotrophic bacteria form the foundation of entire ecosystems at deep-sea hydrothermal vents and cold seeps, but have so far not been reported in terrestrial or freshwater environments. A rare example of a terrestrial ecosystem sustained by chemoautotrophy is found within the sulfide-rich Frasassi limestone cave complex of central Italy. In this study, we report the discovery of abundant filamentous bacteria on the exoskeleton of Niphargus ictus, a macroinvertebrate endemic to Frasassi. Using 16S rDNA sequencing and fluorescence in situ hybridization (FISH), we show that N. ictus throughout the large cave complex are colonized by a single phylotype of bacteria in the sulfur-oxidizing clade Thiothrix. The epibiont phylotype is distinct from Thiothrix phylotypes that form conspicuous biofilms in the cave streams and pools inhabited by N. ictus. Using a combination of 13C labeling, FISH, and secondary ion mass spectrometry (SIMS), we show that the epibiotic Thiothrix are autotrophic, establishing the first known example of a non-marine chemoautotroph-animal symbiosis. Conditions supporting chemoautotrophy, and the N. ictus-Thiothrix association, likely commenced in the Frasassi cave complex between 350 000 and 1 million years ago. Therefore, the N. ictus-Thiothrix symbiosis is probably significantly younger than marine chemoautotrophic symbioses, many of which have been evolving for tens to hundreds of million years.

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.

The hydrogeology of Ogof Draenen: new insights into a complex multi-catchment karst system from tracer testing, 2011, Maurice Lou, Guilford Tim

 A current understanding of the hydrology of Ogof Draenen, Wales, one of the longest and most complex cave systems in Europe, is presented. Previous tracer tests are reviewed and results of two new tracer tests presented. Numerous dolines occur on the Marros Group (formerly ‘Millstone Grit’) sandstones and the Pembroke Limestone Group (both of Carboniferous age) that crop out around the edges of the mountains overlying Ogof Draenen, with hydrologically active sinking streams common along the boundary of these strata. Surface pollution of a doline caused diesel pollution in the cave beneath demonstrating the vulnerability of groundwater. There are a few recently formed hydrologically active passages but groundwater flow is also influenced by many kilometres of relict passages formed during multiple phases of speleogenesis. This results in vertical and horizontal underfit streams that cross or flow through large relict passages. In the southeast of the cave, tracer testing revealed an underground watershed demonstrating the complexity of groundwater flowpaths. In the north a cave stream flows to springs which drain north to the Clydach Gorge. Small amounts of drainage in the cave may also reach springs in the Tumble Valley to the northeast, although these springs may be unconnected to the cave and fed entirely by stream sinks on the Blorenge mountainside. Multi-tracer injections within the cave revealed that the major underground streams flow south to feed large springs at Snatchwood and Pontnewynydd in the Afon Lwyd valley, in a different topographical catchment some 8km beyond the known cave, with rapid groundwater velocities of up to 4km/day. Nine other springs in the Afon Lwyd valley appear unconnected to the Ogof Draenen streams, being fed independently by sinking streams on the local mountainside. In addition, we show that Specific Electrical Conductance varies greatly both between and within springs, is negatively related to background fluorescence


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