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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. ...

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That invaded zone is in geophysical well logging, the zone in which an appreciable amount of mud filtrate has penetrated [16].?

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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 contamination (Keyword) returned 150 results for the whole karstbase:
Showing 121 to 135 of 150
Genesis and functioning of the Aix-les-Bains hydrothermal karst (Savoie, France): past research and recent advances, 2010, Hoblea F. , Gallinojosnin S. , Audra Ph.

Aix-les-Bains (Savoie, France) owes its name and reputation to the thermal springs that occur along the eastern shore of Lake Bourget, France largest natural lake. Although the city waters have been exploited since Antiquity, scientific investigations into the nature and characteristics of the hydrothermal karst from which they emerge did not begin until the early 19th century. The present article traces the history of these investigations and summarizes the results of more than two centuries of scientific research. Today, the only visible signs of karstification related to hydrothermal flows are to be found in the discharge zone in the Urgonian limestone anticline that rises above the city centre. These features are: – the Grotte des Serpents, which houses the Alun Spring, the system main natural discharge, – the Chevalley Aven, a blind chimney that was accidentally uncovered in 1996, – other hydrothermal springs that are too small to enter, including the Soufre Spring. Although scientific investigation of the thermal springs at Aix-les-Bains began in the early 19th century, it was not until the 1920s that scientists started examining the relationship between karstification and the state of the aquifer. E.A.Martel was the first researcher to describe the Aix-les-Bains site as an active hydrothermal karst, in a pioneering study published in 1935. Sixty years later, the discovery of the Chevalley Aven during building work on a new hydrotherapy center gave fresh impetus to research into the karstification of the Aix-les-Bains thermo-mineral aquifer. Recent studies have also investigated the deep aquifer below the karst, using data provided by boreholes. The Urgonian limestone karst at Aix-les-Bains is the site of mixing between thermal waters rising through the anticline and meteoric waters percolating from the surface. Meteoric infiltration is sufficiently high for the hydrological behavior of the thermal springs to be identical to that of exsurgences in gravity-fed, cold-water transmissive karsts. The Chevalley Aven is a shaft that descends 30 meters below the surface, thereby providing access to the ground-water at depth. Monitoring of the water quality in the aven has shown that the Legionella contamination of the springs was due to high concentrations of the bacteria in upstream passages in the karst. In 2006, dye-tracing tests confirmed the existence of a hydraulic connection between the Chevalley Aven and the Alun and Soufre Springs, the fact there is a single ascending hydrothermal conduit, which lies between the Chevalley Aven and the Alun Spring. In addition to providing a valuable source of information about the functioning of the thermo-mineral aquifer, the cavities at Aix-les-Bains are of great karstological interest, especially for the study of hypogene speleogenetic processes. The circulation of warm (40oC), sulfur-rich waters and vapours through the system has led to the development of conduits with specific morphologies and the precipitation of characteristic deposits. These features include: – “beaded” chimneys and galleries formed by the linking of spheres produced by condensation-corrosion. Diffuse karstification along bedding planes around the main conduit; – deposition of non-carbonate minerals (gypsum, native sulfur); – formation of biothems and biofilms on walls subject to condensation. The Grotte des Serpents is a horizontal cavity that formed at the upper limit of the water table. The Chevalley Aven is a hypogene chimney that was sculpted under vadose conditions by the release of sulfuric acid-rich vapours above the thermal water table. As well as a surface coating of microbial mats and the presence of bacterial flakes in the thermal water, the vadose parts of the Aix-les-Bains hydrothermal karst contain a characteristic microfauna and flora. These microorganisms are thought to play an active role in hypogene karstification processes.


Comparative tracing experiments to investigate epikarst structural and compositional heterogeneity, 2011, Sinreich M. , Flynn R.

Comparative tracer testing may be used to evaluate the vulnerability of groundwater to specific contaminants by comparing reactive tracer response to that of a simultaneously injected non-reactive “conservative” substance. Conversely, knowledge of tracer reaction with specific materials permits information about subsurface heterogeneity to be inferred. A series of tests completed in the vadose zone overlying a limestone aquifer employed a cocktail of particles along with reactive and
non-reactive solute tracers to investigate transport rates between the ground surface and monitoring points approximately 10 m below ground. Short pulse tests revealed both solutes and particulate contaminants could travel at rates of over 10 m/h. Comparison of particle (microorganisms) and non-reactive solute tracer breakthrough revealed that particle tracers experience pore exclusion resulting in higher peak relative concentrations which arrive earlier than those of the solute. Prolonged tracer injection during subsequent experiments confirmed the response observed and illustrated that over 40 % of flow paths between
injection and monitoring points were inaccessible to particles, but could allow solutes to pass through them. Similarly, the difference in response between various reactive tracers demonstrated tracers reached monitoring points via multiple flow paths and suggests geochemical heterogeneity plays an important role in influencing tracer behaviour. The results of this investigation highlight the complexity of water flow through the epikarst and the vulnerability of groundwater in karst aquifers to contamination when soil cover is thin to absent.


Potential impact of a proposed railway tunnel on the karst environment: the example of Rosandra valley, Classical Karst Region, Italy-Slovenia, 2011, Zini Luca , Visintin Luca, Cucchi Franco, Boschin Walter

Val Rosandra is a unique geomorphological environment located on the western side of the Classical Karst Plateau (NE Italy). This deep limestone gorge is crossed by a stream that is fed by a large basin located in Slovenia. Val Rosandra is the only example of a karst river valley with surface hydrography in the Classical Karst Plateau. The torrent that crosses it digs a deep gully into the rock, rich in rapids, swirl holes, small waterfalls, enclosed meanders and basins; here, the first seepage phenomena occur, and part of the water feeds the underground aquifer.Val Rosandra is characterised by a complex structural situation. The NE slope culminates in the structure of Mt. Stena, a limestone tectonic wedge between two faults, firmly rooted in the karst platform. Both its external morphology and its caves are influenced by the structure, i.e. by the attitude of bedding planes, fault planes and master joints. Mt. Stena, in particular, hosts a comprehensive net of articulated and diversely shaped caves, basically organised on several levels. This network stretches over a total of 9,000 metres, bearing testimony to ancient geological and hydrogeological origins.The deepest areas of the system reach a suspended aquifer that is probably sustained by an overthrust and placed about 100 meters above the underground aquifer of the Rosandra torrent.A series of feasibility studies on the Trieste-Divača high-speed railway link concentrated on the potential interaction between the project and karst features. In line with the project requirements, risk of voids intersection and water contamination were analyzed as Mt. Stena’s suspended aquifer partially feeds the Rosandra torrent, which flows in a protected natural area. We therefore suggest that further investigations ought to be performed to integrate the existing knowledge on karst and on the hydrogeological aspects of the massif.


Radon and CO2 as natural tracers to investigate the recharge dynamics of karst aquifers, 2011, Savoy Ludovic, Surbeck Heinz, Hunkeler Daniel

This study investigated the use of radon (222Rn), a radioactive isotope with a half-life of 3.8 days, and CO2 as natural tracers to evaluate the recharge dynamics of karst aquifer under varying hydrological conditions. Dissolved 222Rn and carbon dioxide (CO2) were measured continuously in an underground stream of the Milandre test site, Switzerland. Estimated soil water 222Rn activities were higher than baseflow 222Rn activities, indicating elevated 222Rn production in the soil zone compared to limestone, consistent with a 226Ra enrichment in the soil zone compared to limestone. During small flood events, 222Rn activities did not vary while an immediate increase of the CO2 concentration was observed. During medium and large flood events, an immediate CO2 increase and a delayed 222Rn activity increase to up to 4.9 Bq/L and 11 Bq/L, respectively occurred. The detection of elevated 222Rn activities during medium and large flood events indicate that soil water participates to the flood event. A soil origin of the 222Rn is consistent with its delayed increase compared to discharge reflecting the travel time of 222Rn from the soil to the saturated zone of the system via the epikarst. A three-component mixing model suggested that soil water may contribute 4–6% of the discharge during medium flood events and 25–43% during large flood events. For small flood events, the water must have resided at least 25 days below the soil zone to explain the background 222Rn activities, taking into account the half-life of 222Rn (3.8 days). In contrast to 222Rn, the CO2 increase occurred simultaneously with the discharge increase. This observation as well as the CO2 increase during small flood events, suggests that the elevated CO2 level is not due to the arrival of soil water as for 222Rn. A possible explanation for the CO2 trend is that baseflow water in the stream has lower CO2 levels due to gas loss compared to water stored in low permeability zones. During flood event, the stored water is more rapidly mobilised than during baseflow with less time for gas loss. The study demonstrates that 222Rn and CO2 provides value information on the dynamics of groundwater recharge of karst aquifer, which can be of high interest when evaluating the vulnerability of such systems to contamination.


Modified DRASTIC assessment for intrinsic vulnerability mapping of karst aquifers: a case study , 2011, Mimi Ziad A. , Mahmoud Nidal, Abu Madi Maher

Groundwater in karstic aquifers can be dangerously sensitive to contamination. In this paper, DRASTIC assessment was modified and applied, for the first time, to address the intrinsic vulnerability for karst aquifers. The theoretical weights of two of DRASTIC’s parameters (aquifer media and hydraulic conductivity) were modified through sensitivity analysis. Two tests of sensitivity analyses were carried out: the map removal and the single parameter sensitivity analyses. The modified assessment was applied for the karst aquifers underlying Ramallah District (Palestine) as a case study. The aquifer vulnerability map indicated that the case study area is under low, moderate and high vulnerability of groundwater to contamination. The vulnerability index can assist in the implementation of groundwater management strategies to prevent degradation of groundwater quality. The modified DRASTIC assessment has proven to be effective because it is relatively straightforward, use data that are commonly available or estimated and produces an end product that is easily interpreted.


Comparative application of two methods (COP and PaPRIKa) for groundwater vulnerability mapping in Mediterranean karst aquifers (France and Spain) , 2011, Marin A. I. , Dorfliger N. , Andreo O.

A comparative test of two vulnerability mapping methods (COP and PaPRIKa) specifically dedicated to for karst aquifers was carried out on two Mediterranean carbonate aquifers. The vulnerability maps obtained for each aquifer present important differences. To identify and determine the origin of these differences, the results were statistically analyzed using sensitivity analysis, coefficients of determination and scatter graphs. In addition, the global vulnerability (Gv) parameter was used to measure the general vulnerability of the aquifer and to compare the results obtained. This statistical analysis led us to conclude that the main cause of differences between these two methods used to assess aquifer vulnerability lie in the relative importance of the parameters employed in calculating the vulnerability index. For the PaPRIKa method, the variable related to infiltration (slope and karst features) has the most influence, with less weight being assigned to the protective capacity of layers overlying the aquifer. For the COP method, the most influent variable is defined by the layers overlying the aquifer, together with infiltration characteristics, determined by the relative importance of different forms of infiltration in each aquifer. The vulnerability mappings performed using the COP method present greater coherence with the known hydrogeological behavior of the study areas, especially the Spanish aquifers. Nevertheless, further hydrogeological investigations are needed, such as ones to validate the obtained vulnerability maps.


Karst, Uranium, Gold and Water Lessons from South Africa for Reconciling Mining Activities and Sustainable Water Use in Semi-arid Karst Areas: A Case Study, 2011, Winde, Frank

Despite the fact that much of the water stored in dams and reservoirs is lost to the atmosphere due to prevailing semi-arid conditions, South Africa traditionally relies mainly on surface water. Owing to an ever increasing demand that approaches the limits of economically exploitable surface water, the focus increasingly shifts towards groundwater as a long neglected resource. In this context, dolomitic karst aquifers that store large volumes of water protected from evaporation in vast underground cavities are of particular importance. This even more so as some of these aquifers are located in highly industrialised and densely populated areas such as the Gauteng Province, where water demand by far exceeds local supply and necessitates the expensive import of water from catchments as far as Lesotho. However, owing to impacts related to the century-old, deep-level gold mining that initiated South Africa’s economic development, many of the karst aquifers are currently not usable. Using the Far West Rand goldfield as an example, the extent, type and magnitude of mining-related impacts on dolomitic karst aquifers are analysed. This includes impacts on the geohydrological conditions in the area as well as water availability and ground stability associated with the large-scale dewatering of dolomitic aquifers that overly mine workings. Of particular concern is the mining-related contamination of groundwater and surface water with uranium which accompanies gold in most of the mined ore bodies. Finally, possible scenarios for water-related impacts of future mine closure are outlined and associated research needs identified. 


Escherichia coli, other Coliform, and Environmental Chemoheterotrophic Bacteria in Isolated Water Pools from Six Caves in Northern Alabama and Northwestern Georgia, 2011, J. W. Campbell, A. Watson, C. Watson, H. Ball, And R. Pirkle

Escherichia coli and other bacteria can be used as indicators of water quality within a cave ecosystem. However, bacterial species within caves have not been thoroughly documented, especially in the southeastern United States. Water from isolated pools was gathered along transects from six caves in northern Alabama and northwestern Georgia. We used cultivation techniques to isolate and characterize bacteria. Diversity of coliforms and some environmental genera were determined for each cave, and abundance was determined for E. coli and other coliforms. Distance from the entrance in most caves did not statistically correlate with abundance or species richness of bacteria. A total of fifty bacterial species and one fungal species were isolated from the six caves, with over half of these species considered potentially pathogenic in humans. Some species isolated, such as Vibrio alginolyticus and V. fluvialis, are considered primarily marine and are not expected isolates of cave waters. Most of the species we isolated have never been reported from limestone cave ecosystems. Overall, coliforms were found in all tested caves, indicating fecal contamination of all six caves.


Contaminant Transport in Two Central Missouri Karst Recharge Areas, 2011, Lerch, R. N.

Karst watersheds with significant losing streams represent a particularly
vulnerable setting for groundwater contamination because of the direct connection to surface water. Because of the existing agricultural land-use and future likelihood of urbanization, two losing-stream karst basins were chosen for intensive monitoring in Boone County, Missouri: Hunters Cave and Devils Icebox. Both caves were formed in Burlington Limestone and have similar recharge areas (33 to 34 km2) and land uses. Year-round monitoring was conducted from April 1999 through March 2002 to characterize the water quality of the main cave streams relative to herbicide, nutrient, and sediment contamination. Water sampling entailed grab samples at regular intervals and runoff-event samples collected using automated sampling equipment. Total nitrogen, phosphorus, and sediment concentrations and loads were consistently higher in the Devils Icebox stream compared to Hunters Cave. Median total N fluxes were 96 g km22 d21 at Devils Icebox and 30 g km22 d21 at Hunters Cave, while median total P fluxes were 8.5 g km22 d21 at Devils Icebox and 3.3 g km22 d21 at Hunters Cave. Herbicides or their metabolites were detected in more than 80% of the samples from both cave streams, and herbicide concentrations and areal loss rates were generally similar between the sites. Overall, the greater loads and mass flux of contaminants in the Devils Icebox recharge area compared to Hunters Cave was a result of both greater stream discharge and the occurrence of more cropped fields (94%) on claypan soils with high runoff potential. These claypan soils are known to be especially problematic with respect to surface transport of contaminants. Prevailing land use has significantly degraded the water quality in both recharge areas, but a watershed plan has been developed for the Bonne Femme watershed, which encompasses these two recharge areas. With the baseline data collected in this study, the impact of changing land uses and the implementation of management practices or new ordinances designed to improve water quality can be documented.


Revised Hydrogeologic framework for the Floridan Aquifer System in the Northern Coastal Areas of Georgia and Parts of South Carolina, 2011, Gill H. E. , Williams L. J.

The hydrogeologic framework for the Floridan aquifer system was revised for eight northern coastal counties in Georgia and five coastal counties in South Carolina (fig. 1) as part of a regional assessment of water resources by the U.S. Geological Survey (USGS) Groundwater Resources Program. In this study, selected well logs were compiled and analyzed to determine the vertical and horizontal continuity of permeable zones that make up the aquifer system, and define more precisely the thickness of confining beds that separate individual aquifer zones. The results of the analysis indicate that permeable zones in the Floridan aquifer system can be divided into (1) an upper group of extremely transmissive zones that correlate to the Ocala Limestone in Georgia and the Parkers Ferry Formation in South Carolina, and (2) a lower group of zones of relatively lower transmissivity that correlates to the middle part of the Avon Park formation in Georgia and updip clastic equivalent units of South Carolina (fig. 2). This new subdivision simplifies the hydrogeologic framework originally developed by the USGS in the 1980s and helps to improve the understanding of the physical geometry of the system for future modeling efforts. Revisions to the framework in the Savannah–Hilton Head area are particularly important where permeable beds control the movement of saltwater contamination. The revised framework will enable water-resource managers in Georgia and South Carolina to assess groundwater resources in a more uniform manner and help with the implementation of sound decisions when managing water resources in the aquifer system


Radon and CO2 as natural tracers to investigate the recharge dynamics of karst aquifers, 2011, Savoy Ludovic, Surbeck Heinz, Hunkeler Daniel

This study investigated the use of radon (222Rn), a radioactive isotope with a half-life of 3.8 days, and CO2 as natural tracers to evaluate the recharge dynamics of karst aquifer under varying hydrological conditions. Dissolved 222Rn and carbon dioxide (CO2) were measured continuously in an underground stream of the Milandre test site, Switzerland. Estimated soil water 222Rn activities were higher than baseflow 222Rn activities, indicating elevated 222Rn production in the soil zone compared to limestone, consistent with a 226Ra enrichment in the soil zone compared to limestone. During small flood events, 222Rn activities did not vary while an immediate increase of the CO2 concentration was observed. During medium and large flood events, an immediate CO2 increase and a delayed 222Rn activity increase to up to 4.9 Bq/L and 11 Bq/L, respectively occurred. The detection of elevated 222Rn activities during medium and large flood events indicate that soil water participates to the flood event. A soil origin of the 222Rn is consistent with its delayed increase compared to discharge reflecting the travel time of 222Rn from the soil to the saturated zone of the system via the epikarst. A three-component mixing model suggested that soil water may contribute 4–6% of the discharge during medium flood events and 25–43% during large flood events. For small flood events, the water must have resided at least 25 days below the soil zone to explain the background 222Rn activities, taking into account the half-life of 222Rn (3.8 days). In contrast to 222Rn, the CO2 increase occurred simultaneously with the discharge increase. This observation as well as the CO2 increase during small flood events, suggests that the elevated CO2 level is not due to the arrival of soil water as for 222Rn. A possible explanation for the CO2 trend is that baseflow water in the stream has lower CO2 levels due to gas loss compared to water stored in low permeability zones. During flood event, the stored water is more rapidly mobilised than during baseflow with less time for gas loss. The study demonstrates that 222Rn and CO2 provides value information on the dynamics of groundwater recharge of karst aquifer, which can be of high interest when evaluating the vulnerability of such systems to contamination.


Engineering Issues on Karst, 2011, Zhou Wanfang, Beck Barry F.

The design and construction of engineering structures in karst regions must deal with such challenges as difficulty in excavating and grading the ground over pinnacled rockheads, instability of ground surface, and unpredictable groundwater flow conditions. Detailed subsurface investigation using boring exploration, geophysical techniques, tracer testing, and groundwater monitoring helps optimize foundation designs and minimize uncertainties inherent in their construction. Based on the maturity of karst landscapes, depth and dimension of karst features, and vulnerability of groundwater contamination, methods that have been established to control surface water and groundwater and minimize sinkhole development include relocating structures to a safer site, filling voids/fractures with concrete, soil reinforcement, constructing deep foundations, and remediating sinkholes.


Radon and CO2 as natural tracers to investigate the recharge dynamics of karst aquifers, 2011, Savoy Ludovic, Surbeck Heinz, Hunkeler Daniel

This study investigated the use of radon (222Rn), a radioactive isotope with a half-life of 3.8 days, and CO2 as natural tracers to evaluate the recharge dynamics of karst aquifer under varying hydrological conditions. Dissolved 222Rn and carbon dioxide (CO2) were measured continuously in an underground stream of the Milandre test site, Switzerland. Estimated soil water 222Rn activities were higher than baseflow 222Rn activities, indicating elevated 222Rn production in the soil zone compared to limestone, consistent with a 226Ra enrichment in the soil zone compared to limestone. During small flood events, 222Rn activities did not vary while an immediate increase of the CO2 concentration was observed. During medium and large flood events, an immediate CO2 increase and a delayed 222Rn activity increase to up to 4.9 Bq/L and 11 Bq/L, respectively occurred. The detection of elevated 222Rn activities during medium and large flood events indicate that soil water participates to the flood event. A soil origin of the 222Rn is consistent with its delayed increase compared to discharge reflecting the travel time of 222Rn from the soil to the saturated zone of the system via the epikarst. A three-component mixing model suggested that soil water may contribute 4–6% of the discharge during medium flood events and 25–43% during large flood events. For small flood events, the water must have resided at least 25 days below the soil zone to explain the background 222Rn activities, taking into account the half-life of 222Rn (3.8 days). In contrast to 222Rn, the CO2 increase occurred simultaneously with the discharge increase. This observation as well as the CO2 increase during small flood events, suggests that the elevated CO2 level is not due to the arrival of soil water as for 222Rn. A possible explanation for the CO2 trend is that baseflow water in the stream has lower CO2 levels due to gas loss compared to water stored in low permeability zones. During flood event, the stored water is more rapidly mobilised than during baseflow with less time for gas loss. The study demonstrates that 222Rn and CO2 provides value information on the dynamics of groundwater recharge of karst aquifer, which can be of high interest when evaluating the vulnerability of such systems to contamination.


Comparative microbial sampling from eutrophic caves in Slovenia and Slovakia using RIDA COUNT test kits, 2012, Mulec Janez, Kritů, Fek Vclav, Chroň, kov Alica

RIDA®COUNT test plates were used as an easy-to-handle and rapid indicator of microbial counts in karst ecosystems of several caves in Slovakia and Slovenia. All of the caves had a high organic input from water streams, tourists, roosting bat colonies or terrestrial surroundings. We sampled swabs, water and air samples to test robustness and universality of the RIDA®COUNT test kit (R-Biopharm AG, Germany, http://www.r-biopharm.com/) for quantification of total bacteria, coliforms, yeast and mold. Using data from swabs (colony-forming units per cm2) we proposed a scale for description of biocontamination level or superficial microbial load of cave niches. Based on this scale, surfaces of Ardovská Cave, Drienovská Cave and Stará Brzotínská Cave (Slovakia) were moderately colonized by microbes, with total microbial counts (sum of total bacterial count and total yeast and molds count) in the range of 1 001-10 000 CFU/100 cm2, while some surfaces from the show cave Postojna Cave (Slovenia) can be considered highly colonized by microbes (total microbial counts ≥ 10 001 CFU/100 cm2). Ardovská Cave also had a high concentration of air-borne microbes, which can be explained by restricted air circulation and regular bat activity. The ratio of coliform to total counts of bacteria in the 9 km of underground Pivka River flow in Postojna Cave dropped approximately 4-fold from the entrance, indicating the high anthropogenic pollution in the most exposed site in the show cave. The RIDA®COUNT test kit was proven to be applicable for regular monitoring of eutrophication and human influence in eutrophic karst caves.


Comparative study of specific groundwater vulnerability of a karst aquifer in central Florida, 2012, Van Beynen P. E. , Niedzielski M. A. , Bialkowskajelinska E. , Alsharifa K. , Matusick J.

The Floridan aquifer system (FAS) is known to be one of the most productive aquifer systems in the USA. With the FAS being a karst aquifer, it presents unique challenges to land use planners because of inherent vulnerabilities to contamination through direct connections between the aquifer and the surface. In this study a new Geographic Information Systems (GIS) -based index, the Karst Aquifer Vulnerability Index (KAVI), incorporates geologic layers used in intrinsic groundwater vulnerability models (GVMs) plus an epikarst layer specific to karst, with land use coverages to create a specific groundwater vulnerability model. The KAVI model was compared to another specific vulnerability model, the Susceptibility Index (SI). Tabulation of the percentage areas of vulnerability classes reveals major differences between the two models with SI suggesting greater vulnerability for the study area than KAVI. Validation of these two models found that KAVI vulnerability levels best reproduced spatially varying concentrations of nitrate in the aquifer. Sensitivity analysis, the application of a variation index and measuring the effective weights for each parameter included in KAVI confirmed the importance of closed depressions but also aquifer hydraulic conductivity. The inclusion of land use was justified; however, effective weight analysis determined its assigned weight was too high as used in the initial calculation of KAVI.


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