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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 tributary river is a smaller stream entering and contributing to the flow of a larger river [16].?

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

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What is Karstbase?



Browse Speleogenesis Issues:

KarstBase a bibliography database in karst and cave science.

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;
See all featured articles from other geoscience journals

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Your search for variation (Keyword) returned 464 results for the whole karstbase:
Showing 436 to 450 of 464
Characterizing moldic and vuggy pore space in karst aquifers using borehole-wall, slabbed-core and thin-section images, 2013,
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Manda A. K. , Culpepper A. R.

Carbonate aquifers are prolific and important sources of potable water in many parts of the world owing toenlarged dissolution features that enhance porosity and interconnectivity. To better understand the variationsof pore space in different karst aquifers, image and geospatial analyses are used to analyze pore attributes(i.e., pore area and perimeter) in images of vuggy aquifers. Pore geometry and 2D porosity derivedfrom images of the moldic Castle Hayne and vuggy Biscayne aquifers are analyzed at three scales of observation:borehole televiewer, core and thin-section. The Castle Hayne and Biscayne aquifers are the foci of thisstudy because the pore spaces that control the hydrologic properties in each of these aquifers are markedlydifferent even though both of these carbonate reservoirs are prolific aquifers. Assessments of pore area,perimeter and shape index (a measure of shape complexity) indicate that pore geometries and pore complexitiesvary as a function pore type and scale of observation. For each aquifer type, the areas, perimetersand complexities of pores are higher at the larger scale of observation (e.g., borehole) than the smallerscale of observation (e.g., thin section). When the complexity of the moldic pores is compared to the complexityof vuggy pores, the results indicate that moldic pores are generally more complex than vuggy poresat the same scale of observation. Whereas estimates of 2D porosity from the borehole televiewer image ofthe vuggy aquifer are higher than those derived from the moldic aquifer, the range of 2D porosities is largerin core and thin section images for the vuggy aquifer than themoldic aquifer. A model for the development ofpores is presented that suggests that the coalescence of small pores with simple shapes leads to the growth oflarger pores with more complex shapes. The model suggests that the younger Biscayne aquifer is a moremature karst than the Castle Hayne aquifer.

Temporal Variability of cave-Air CO2 in Central Texas, 2013,
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Cowan B. D. , Osborne M. C. , Banner J. L.


The growth rate and composition of cave calcite deposits (speleothems) are often used as proxies for past environmental change. There is, however, the potential for bias in the speleothem record due to seasonal fluctuations in calcite growth and dripwater chemistry. It has been proposed that the growth rate of speleothem calcite in Texas caves varies seasonally in response to density-driven fluctuations in cave-air CO2, with lower growth rates in the warmer months when cave-air CO2 is highest. We monitored CO2 in three undeveloped caves and three tourist caves spread over 130 km in central Texas to determine whether seasonal CO2 fluctuations are confined to tourist caves, which have been modified from their natural states, and the extent to which cave-air CO2 is controlled by variations in cave geometry, host rocks, cave volume, and soils. Nearly 150 lateral transects into six caves over three years show that CO2 concentrations vary seasonally in five of the caves monitored, with peak concentrations in the warmer months and lower concentrations in the cooler months. The caves occur in six stratigraphic units of lower Cretaceous marine platform carbonate rocks and vary in volume (from 100 to .100,000 m3) and geometry. Seasonal CO2 fluctuations are regional in extent and unlikely due to human activity. Seasonal fluctuations are independent of cave geometry, volume, depth, soil thickness, and the hosting stratigraphic unit. Our findings indicate that seasonal variations in calcite deposition may introduce bias in the speleothem record, and should be considered when reconstructing paleoclimate using speleothem proxies.

A model for the formation of layered soda-straw stalactites, 2013,
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Paul Bence, Drysdale R. , Green Helen, Woodhead Jon, Hellstrom John, Eberhard Rolan

Climate records based upon instrumental data such as rainfall measurements are usually only available for approximately the last 150 years at most. To fully investigate decadal-scale climate variation, however, these records must be extended by the use of climate proxies. Soda-straw stalactites (straws) are a previously under-utilised potential source of such data. In this contribution we investigate the structure and formation of straws and look at some issues that may affect the reliability of straw-based palaeoclimate records. We use laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) trace element analysis to document surface contamination features that have the potential to obscure annual trace element variations, and develop a method to reveal the underlying layering. We also use LA- ICP-MS to map the two-dimensional trace element distribution in straws. These maps reveal straw-layer geometry, in which layers are widest at the outside edge of the straw, narrowing and becoming almost parallel on the interior of the straw.

Based upon these observations, we present a model for the formation of straws of this type, where rapid degassing of CO2 from the drip extending below the straw forms the wider outer layers. Summers are defined by increased layer widths and higher trace element contents relative to winter layers. In palaeoclimate studies, where such annual variations can be used to construct time-lines, we suggest that, ideally, the outside surface of the straw be analysed where the trace element content difference is greatest and layering is widest.

The terminal phase of one straw (FC-02) shows decreasing layer widths and increased trace element contents. These features may also be representative of soda-straw responses to drought-induced decreases in percolation water.

Mycological study for a management plan of a neotropical show cave (Brazil)., 2013,
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Taylor E. L. S, Resendestoianoff M. A. A, Lopes Ferreira R.

Caves are stable environments with characteristics favoring the development of microorganisms. The allocthonous input of organic matter and microbes into the warm Neotropical caves may favor the development of filamentous fungi, including pathogenic species. Histoplasma capsulatum is a pathogenic species commonly found in caves and associated with bat and bird guano. Many Brazilian caves have been historically visited due to scenic and religious tourism. The objective of this study was to perform a microbiology study for a management plan of a show cave in Brazil, focusing on the presence and distribution of pathogenic and opportunistic fungi in the cave. Statistic analysis was used to verify the influence of touristic activity on airborne fungi spore load. Fungi were isolated from air and guano in Lapa Nova Cave. Samples were obtained through serial dilution, direct and settle plate techniques. For H. capsulatum, samples were incubated in specific media and conditions. Airborne fungal spore load was compared prior and during visitation and statistically analyzed. A total of 2,575 isolates from the genera Aspergillus, Calcarisporium, Chaetomium, Cladosporium, Curvularia, Emericella, Eurotium, Fusarium, Geotrichum, Gliocladium, Mucor, Purpureocillium, Paecilomyces, Penicillium, Rhizopus and Trichoderma were identified. Histoplasma capsulatum was not isolated from the cave. Eleven opportunistic species were identified. Significant (p<0.05) variations on fungal richness in the air occurred due to cave visitation. Areas of potential microbiologic risks were indicated and management actions suggested. The results suggest a diverse community inhabiting the cave. Possible opportunistic species should be monitored in show caves and microbiota should always be included in the elaboration of cave management plans. This is the first detailed microbiologic study for a management plan of a show cave in the country. It provides relevant information for future management plans.

Hydrothermal variation in several deep caves of the Nullarbor Karst Plain, Australia, 2013,
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Lewis Ian D. , Buzzacott Peter

Differences in aquatic microcrustacean assemblages between temporary and perennial springs of an alpine karstic aquifer, 2013,
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Mori N. , Brancelj A.

Microcrustacean (Copepoda, Ostracoda) assemblages were investigated at the interface of the vadose and phreatic zones in the alpine karstic aquifer from the Julian Alps in Slovenia (SE Europe). Two temporary and one perennial karstic outlets were sampled by filtering the water several times over 2 years. Concurrently, benthos from the mouth of a perennial spring and from an adjacent spring brook were collected. Altogether 24 microcrustacean species were recorded. The spatial and temporal variation in drift densities and species composition was high indicating complex groundwater hydrological pathways being dependent on precipitation regime. Non-metric Multidimensional Scaling (NMDS) clearly separated drift samples from temporary springs and other sample groups (drift in perennial spring, spring mouth and spring brook benthos). ANOSIM revealed statistically significant differences between all sample groups (Diacyclops zschokkei, Elaphoidella phreatica and Mixtacandona sp. B contributed over 50 % to the observed differences among sample groups. Three species (Nitocrella sp., Speocyclops infernus, Lessinocamptus pivai), known to be typical epikarst species, were collected only in the drift from one temporary spring (T2). Mao Tau species accumulation curves did not reach asymptote for the drift from temporary springs, but did for the drift from perennial spring, and for the spring mouth and the spring brook benthos. The results on drift composition indicated the variation in the origin of the water discharging at the interface of vadoze and phreatic zones depending greatly on water level conditions, while the drift densities were higher in the water presumably discharging from phreatic zone (perennial spring and temporary springs during low water levels).

Hydrothermal variation in several deep caves of the Nullarbor Karst Plain, Australia, 2013,
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Lewis Ian D. , Buzzacott Peter

Spatial and temporal changes in invertebrate assemblage structure from the entrance to deep-cave zone of a temperate marble cave, 2013,
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Tobin Benjamin W. , Hutchins Benjamin T. , Schwartz Benjamin F.

Seasonality in surface weather results in seasonal temperature and humidity changes in caves. Ecological and physiological differences among trogloxenes, troglophiles, and troglobionts result in species-dependent responses to this variability. To investigate these responses, we conducted five biological inventories in a marble cave in the Sierra Nevada Range, California, USA between May and December 2010. The cave was divided into six quadrats and temperature was continuously logged in each (humidity was logged at the entrance and in the deep cave). With increasing distance from the entrance, temperature changes were increasingly attenuated and lagged relative to surface temperature. Linear regressions were created to determine the relationship between measured environmental variables and diversity for cavernicoles (troglobionts and troglophiles) and trogloxenes cave– wide and in the transition zone. Diversity for cavernicoles and trogloxenes peaked in the entrance and deep cave zones, respectively. Quadrat, date, 2-week antecedent temperature average, 2-week antecedent temperature range, and trogloxene abundance explained 76% of cavernicole diversity variability. Quadrat explained 55% of trogloxene diversity variability. In the transition zone, trogloxene abundance explained 26% of cavernicole variability and 2-week antecedent temperature and 2-week antecedent temperature range explained 40% of trogloxene variability. In the transition zone, trogloxene diversity was inversely related to 2-week antecedent temperature average and 2-week antecedent temperature range, suggesting that species were moving into the transition zone when temperature was most stable. In a CCA of cavernicoles distribution data and environmental variables, 35% of variation in species-specific distributions was attributable to quadrat, and non-significant percentages were explained by date and environmental variables. Differences in assemblage structure among quadrats were largely due to differences between distributions of trogloxenes and cavernicoles, but responses varied among species. Differences are likely due to ecological niche width, physiological constraints, and competition.

Effects of sinuosity factor on hydrodynamic parameters estimation in karst systems: a dye tracer experiment from the Beyyayla Sinkhole (Eskişehir, Turkey), 2013,
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Aydin H. , Ekmekci M. , Soylu M. E.

The sinuosity factor (SF) is a critical value in karst systems in terms of estimating their hydrodynamic parameters including groundwater velocity, coefficient of dispersion, etc., through dye tracer experiments. SF has been used in a number of different dye tracer experiments in karstic systems to estimate a representative flow path. While knowing SF is crucially important in the estimation of hydrodynamic parameters, its calculation is associated with significant uncertainty due to the complexity of subsurface karstic features. And yet, only a few studies have discussed its uncertainties, which might lead some errors in estimation of hydrodynamic parameters from dye tracer experiment. In this study, dye tracer experiments were conducted in two consecutive years (2003 and 2004) representing low and high flow conditions in the Beyyayla sinkhole (Eskişehir, Turkey) where the flow path is well known. Uranine was used in experiments as a tracer and QTRACER computer program was used to determine the hydrodynamic properties of the Beyyayla karst system as well as to gain insights into the effects of SF from dye tracer experiments on estimated parameters. The results showed that the breakthrough curve follows a unimodal and a bimodal distribution in low and high flow conditions, respectively. These different distributions stem from the water transport mechanisms, where velocities were calculated as 58.2 and 93.6 m h−1 during low and high flow conditions observed in a spring emerging from the south side of the studied system. The results also show that the coefficient of dispersion, Reynolds number, and Peclet number increased and longitudinal dispersivity decreased with the higher flow rate. Furthermore, the estimated parameters did not vary with either the flow conditions or the tracer transit time, but they have shown some variations with SF. When SF was increased by 50 %, a change in these parameters was obtained in the range of 50–125 %.

Shape variation of Aegla schmitti (Crustacea, Decapoda, Aeglidae) associated to superficial and subterranean stream reaches, 2013,
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Camile Fernandes, Maria Bichuette

The species Aegla schmitti is relatively abundant in epigean streams in the Upper Ribeira Basin, southeastern Brazil and has a few records in caves. In this study, we questioned if those individuals would be an accidental presence or could be populations already established in cave streams? In this case, would morphological variations be associated with superficial and subterranean stream reaches? In this exploratory survey we tried to answer these questions by assessing the shape variation of cephalothorax using landmark-based geometric morphometrics. Different shapes were found for both environments, evidencing a successful hypogean colonization. The area effect was discarded as being the unique factor responsible for the divergence, therefore, for the first time in the literature, here we report morphological modifications associated with subterranean colonization in troglophiles. We also conceived and discussed some hypotheses about the colonization.

Detritus processing in lentic cave habitats in the neotropics, 2013,
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Marconi Souza Silva, Rafaelly Karina Sales Rezende, Rodrigo Lopes Ferreira

Lentic cave habitatsare almost always heterotrophic habitats where there are food and oxygen input from the surface. This hydrological exchange seems to be the key factor shaping most groundwater communities. Litter processing in cave water environments has not been experimentally studied as much as it has in lotic subterranean systems, although detritus is likely a critical resource for organisms inhabiting shallow groundwater habitats. The present study sought to evaluate the processing rates and the nitrogen and phosphorous dynamics in plant debris deposited in lentic habitats of two Neotropical limestone caves during 99 days. 84–10×10 cm2 litterbags with mesh sizes of 0.04 mm2 and 9 mm2 were used. In each weighed litter bag, 50 green, intact plant leaf disks (± 2.0 gr/bag) were conditioned. At the end of the experiment, the average weight loss was only 17.4%. No macroinvertebrates were found associated to the debris, but significant differences in the processing rate in relation to the cave and mesh size were observed. The weight loss rate of the plant debris was considered slow (average 0.003 K-day). The amount of nitrogen and remaining phosphorous in the plant debris in the two caves showed variations over time with a tendency to increase probably due to the development of microorganisms which assimilate nitrogen and phosphorus. The slow processing rate of the plant debris can be due mainly to the fact that these lentic cave habitats are restrictive to colonization by shredder invertebrates. Furthermore, the abrasive force of the water, which plays an important role in the processing and availability of fragmented debris for colonization by microorganisms, is absent.

Population size and dispersal patterns for a Drimeotus (Coleoptera, Leiodidae, Leptodirini) cave population, 2013,
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Akos Fejr, Oana Teodora Moldovan

Drimeotus viehmanni (ColeopteraLeiodidae) is abundant in the cave Peştera cu Apă din Valea Leşului (Western Carpathians) and was chosen for a mark-release-resight experiment. The aims of the experiment were to estimate the size of the population and to analyze the dispersal patterns inside the cave, for conservation purposes. During the three years’ study, the observed abundance of Drimeotus viehmanni was significantly higher in summer compared to the winter season. The seasonal dynamics can not be explained by climate features such as temperature and air relative humidity which had low or no variation during all seasons. Few marked beetles were re-seen during the mark-resight experiment proving the existence of an important cave/subterranean population, which was estimated between 5, 084 and 533, 033 individuals. The marked individuals moved between neighbouring patches on a distance of 10 m over the same amount of time as on distances longer than 200 m. Dispersal inside the cave occurs during the winter months, which indicates non-continuous behaviour triggered by environmental features and involving only a negligible part of the population in the studied cave.

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Neal J. T. , Johnson K. S. , Lindberg P.

At least six distinct forms of evaporite karst occur in the Holbrook Basin•depending considerably on overburden and/or bedrock type. Early Permian evaporites in the 300-m-thick Corduroy Member of the Schnebly Hill Formation include halite, sylvite, and anhydrite at depths of 215-250 m. Karst features result from collapse of overlying Permian and Triassic strata into underlying salt-dissolution cavities. Evaporite karst occurs primarily along the 100+ km-long dissolution front on the southwestern edge of the basin, and is characterized by numerous sinkholes and depressions generally coincident with the axis of the Holbrook Anticline•in reality a dissolution-collapse monocline. “The Sinks” comprise ~ 300 individual sinks up to 200 m across and 50 m deep, the main karst features along the dissolution front. Westerly along the dissolution front, fewer discrete sinkholes occur, and several breccia pipes are believed to be forming. Numerous pull-apart fissures, graben-sinks, sinkholes, and broad collapse depressions also occur.A newly recognized subsidence/collapse area of some 16 km2 occurs in the western part of the basin, northward from the extension of the Holbrook “anticline.” The Chimney Canyon area is some 12 km east of McCauley Sinks, a postulated breccia pipe exemplified in, and possibly manifested in at least four other closed depressions. Interferometric Synthetic Aperture Radar (InSAR) data of one depression shows active subsidence of ~4 cm/yr.Karst formation is ongoing, as shown by repeated drainage of Dry and Twin Lakes into newly opened fissures and sinkholes. These two playa lakes were enlarged and modified in recent years into evaporation 2impoundments for effluent discharge from a nearby pulp mill. Four major drainage events occurred within these playa reservoirs during the past 45 years, collectively losing more than 1.23 x107 m3 (10,000 acre-feet) of water and playa sediment. Drainage occurs through piping into bedrock joints in Triassic Moenkopi Formation (sandstone) in the bottom and along the margins of these playas. Effluent discharge has been discontinued into these playas, although recurring precipitation can fill the basins.

Early results of micro-deformation measurements in Magdalena Jama (Slovenia) by a vertical static pendulum, 2013,
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Kalenda Pavel, Neumann Libor, Šebela Stanka

Vertical static pendulums have been installed in mines or caves in Central Europe since 2007. Two­dimensional optical measurement of the tilt of a rock mass and continuous fully digital on­line evaluation of results makes possible the detection of a small tilt of the surroundings with a resolution of tens of nanoradians or the deformation of the surroundings in the horizontal plane with resolution of hundreds of nanometres. The paper describes the measurement device and the first results of the measurements in Magdalena Jama, which is part of the Postojna Cave System (Slovenia). The correlation of deformation between distant stations shows the existence of stress variations that are not only of local origin (high floods, local seismicity, and aseismic deformations). The stress field has a wider, and not only regional, character with effects that can be observed very far from the origin.

Organic matter flux in the epikarst of the Dorvan karst, France, 2013,
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Simon, Kevin S.

Availability of organic matter plays an important role in karst ecosystems. Somewhat surprisingly, study of the composition and distribution of organic matter in karst aquifers is rare. The most comprehensive study or organic matter flux to date is a two year continuous monitoring of detritus and animal flux in epikarst drip waters and an epikarst-fed cave stream in the Dorvan karst, France. Analysis of those data reveals high temporal variation in detritus and animal flux in both habitats, but little evidence of seasonality in flux. water flux explained 30-69% of the variation in animal flux in both habitats and detritus flux in the epikarst seepage water. Detritus flux in the cave stream was better explained by peak monthly discharge. Lack of coherence between organic matter flux in epikarst seepage and the epikarst stream suggests organic matter transport is governed by differing factors in the two habitats. Overall, much of the particulate organic matter flux in the epikarst occurs as living animals suggesting a dominant role of ecological processes in organic matter transport.

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