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Enviroscan Ukrainian Institute of Speleology and Karstology


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Community news

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 degree of saturation is see percent saturation.?

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


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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;
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Your search for requirements (Keyword) returned 30 results for the whole karstbase:
Showing 16 to 30 of 30
Radon in caves, 2005,
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Cigna A, A.
The physical characteristics of radon are reported as well as its sources, the transport in rock and its behaviour in caves. Then, the instruments, both active and passive, used for the measurement of radon concentration are discussed by taking into account their respective advantages and disadvantages for the use in the cave environment. Since in many countries radon is the object of regulations that were adopted for radiation protection purposes, this aspect is examined and the recommendations issued by international organisations and enforced in different countries are reported. Materials, methods and other remarks on the limits implementation are also listed with the aim of providing the managers of show caves with some instruments to comply with the domestic requirements with the most convenient solution.

Ecology and hydrology of a threatened groundwater-dependent ecosystem: the Jewel Cave karst system in Western Australia, PhD Thesis, 2005,
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Eberhard, S. M.

Groundwater is a significant component of the world’s water balance and accounts for >90 % of usable freshwater. Around the world groundwater is an important source of water for major cities, towns, industries, agriculture and forestry. Groundwater plays a role in the ecological processes and ‘health’ of many surface ecosystems, and is the critical habitat for subterranean aquatic animals (stygofauna). Over-abstraction or contamination of groundwater resources may imperil the survival of stygofauna and other groundwater-dependent ecosystems (GDEs). In two karst areas in Western Australia (Yanchep and Leeuwin-Naturaliste Ridge), rich stygofauna communities occur in cave waters containing submerged tree roots. These aquatic root mat communities were listed as critically endangered because of declining groundwater levels, presumably caused by lower rainfall, groundwater abstraction, and/or forest plantations. Investigation of the hydrology and ecology of the cave systems was considered essential for the conservation and recovery of these threatened ecological communities (TECs). This thesis investigated the hydrology and ecology of one of the TECs, located in the Jewel Cave karst system in the Leeuwin-Naturaliste Ridge. A multi-disciplinary approach was used to explore aspects pertinent to the hydrology and ecology of the groundwater system.
Thermoluminescence dating of the limestone suggested that development of the karst system dates from the Early Pleistocene and that caves have been available for colonisation by groundwater fauna since that time. Speleogenesis of the watertable maze caves occurred in a flank margin setting during earlier periods of wetter climate and/or elevated base levels. Field mapping and leveling were used to determine hydrologic relationships between caves and the boundaries of the karst aquifer. Monitoring of groundwater levels was undertaken to characterise the conditions of recharge, storage, flow and discharge. A hydrogeologic model of the karst system was developed.
The groundwater hydrograph for the last 50 years was reconstructed from old photographs and records whilst radiometric dating and leveling of stratigraphic horizons enabled reconstruction of a history of watertable fluctuations spanning the Holocene to Late Pleistocene. The watertable fluctuations over the previous 50 years did not exceed the range of fluctuations experienced in the Quaternary history, including a period 11,000 to 13,000 years ago when the watertable was lower than the present level.
The recent groundwater decline in Jewel Cave was not reflected in the annual rainfall trend, which was above average during the period (1976 to 1988) when the major drop in water levels occurred. Groundwater abstraction and tree plantations in nearby catchments have not contributed to the groundwater decline as previously suggested. The period of major watertable decline coincided with a substantial reduction in fire frequency within the karst catchment. The resultant increase in understorey vegetation and ground litter may have contributed to a reduction in groundwater recharge, through increased evapotranspiration and interception of rainfall. To better understand the relationships between rainfall, vegetation and fire and their effects on groundwater recharge, an experiment is proposed that involves a prescribed burn of the cave catchment with before-after monitoring of rainfall, leaf-area, ground litter, soil moisture, vadose infiltration and groundwater levels.
Molecular genetic techniques (allozyme electrophoresis and mitochondrial DNA) were used to assess the species and population boundaries of two genera and species of cave dwelling Amphipoda. Populations of both species were largely panmictic which was consistent with the hydrogeologic model. The molecular data supported the conclusion that both species of amphipod have survived lower watertable levels experienced in the caves during the Late Pleistocene. A mechanism for the colonization and isolation of populations in caves is proposed.
Multi Dimensional Scaling was used to investigate patterns in groundwater biodiversity including species diversity, species assemblages, habitat associations and biogeography. Faunal patterns were related to abiotic environmental parameters. Investigation of hydrochemistry and water quality characterized the ecological water requirements (EWR) of the TEC and established a baseline against which to evaluate potential impacts such as groundwater pollution.
The conservation status of the listed TEC was significantly improved by increasing the number of known occurrences and distribution range of the community (from 10 m2 to > 2 x 106 m2), and by showing that earlier perceived threatening processes (rainfall decline, groundwater pumping, tree plantations) were either ameliorated or inoperative within this catchment. The GDE in the Jewel Cave karst system may not have been endangered by the major phase of watertable decline experienced 1975-1987, or by the relatively stable level experienced up until 2000. However, if the present trend of declining rainfall in southwest Western Australia continues, and the cave watertable declines > 0.5 m below the present level, then the GDE may become more vulnerable to extinction.
The occurrence and distribution of aquatic root mat communities and related groundwater fauna in other karst catchments in the Leeuwin-Naturaliste Ridge is substantially greater than previously thought, however some of these are predicted to be threatened by groundwater pumping and pollution associated with increasing urban and rural developments. The taxonomy of most stygofauna taxa and the distribution of root mat communities is too poorly known to enable proper assessment of their conservation requirements. A regional-scale survey of stygofauna in southwest Western Australia is required to address this problem. In the interim, conservation actions for the listed TECs need to be focused at the most appropriate spatial scale, which is the karst drainage system and catchment area. Conservation of GDEs in Western Australia will benefit from understanding and integration with abiotic groundwater system processes, especially hydrogeologic and geomorphic processes.


Ecology and hydrology of a threatened groundwater-dependent ecosystem: the Jewel Cave karst system in Western Australia [abstract], 2006,
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Eberhard S. M.
This thesis investigates the hydrology and ecology of a threatened aquatic root mat community in the Jewel Cave karst system in the Leeuwin-Naturaliste Ridge, Western Australia. Development of the karst system dates from the Early Pleistocene and the caves have been available for colonisation by groundwater fauna since that time. Speleogenesis of the watertable maze caves occurred in a flank margin setting during earlier periods of wetter climate and/or elevated base levels. Watertable fluctuations over the last 50 years did not exceed the range experienced in the Quaternary history. The recent groundwater decline in Jewel Cave was not related to rainfall, nor groundwater abstraction nor nearby tree plantations. However, it did coincide with a reduction in fire frequency within the karst catchment. The resultant increase in understorey vegetation and ground litter may have reduced groundwater recharge through increased evapotranspiration and interception of rainfall. The populations of two genera and species of cave dwelling Amphipoda are largely panmictic. Both species have survived lower watertable levels during the Late Pleistocene. A mechanism for the colonization and isolation of populations in caves is proposed. Faunal patterns (including species diversity, species assemblages, habitat associations and biogeography) were related to abiotic environmental parameters. The ecological water requirements of the community were determined as a baseline for evaluation of impacts such as groundwater pollution. If rainfall continues to decline, and the cave watertable declines > 0.5 m below the present level, then the groundwater ecosystem may become more vulnerable to extinction. The taxonomy and distribution of root mat communities is poorly known and a regional-scale survey is required to properly assess their conservation requirements. Meanwhile, conservation actions for the communities need to be focused at the scale of the karst drainage system and catchment area.

U-series dating and taphonomy of Quaternary vertebrates from Brazilian caves, 2006,
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Auler As, Pilo Lb, Smart Pl, Wang X, Hoffmann D, Richards Da, Edwards Rl, Neves Wa, Cheng H,
The geochronology and taphonomy of internationally important fossil bearing cave deposits were studied, both in the semi-arid Northern Bahia area and the subtropical southeastern Lagoa Santa area of Brazil. Taphonomic analysis suggests that the processes responsible for bone accumulation in the Brazilian caves vary between sites, and taphonomic bias can therefore be significant in causing differences in faunal composition. In the Toca da Boa Vista caves the presence of single articulated skeletons, and the entrance-related distribution indicate that random penetration of animals is the main mechanism of fossil accumulation, a process that biases the assemblage to smaller species, and takes place over extended time periods. In nearby Toca dos Ossos cave transport by runoff in the cave river is predominant, and biases the fauna remains to larger more robust bones and species. Deposition probably also occurred only at times of enhanced runoff giving a more contemporaneous assemblage. Similar processes were responsible for emplacement of the copious fossil remains in the more humid Lagoa Santa area, where terrigenous fossil deposits are found intercalated by massive speleothem calcite layers. In this area runoff under a drier climate probably accounts for the sediment emplacement inside caves. In both areas the mode of emplacement implies bias in the fossil record, resulting in fossil assemblages that do not mirror surface faunas, limiting palaeoenvironmental reconstruction.Mass spectrometric U-series analysis of speleothem calcite overlaying fossil remains gives minimum ages for fossil deposition. These ages confirm the previous view that many of the deposits derive from the late glacial, but also show that much older material (some > 350,000[no-break space]yr) is also present. The habitat requirements of critical fossil species such as bats and monkeys strongly suggest that they derive from much wetter periods when forest cover was present in the currently semi-arid Northern Bahia area. Taphonomy exerts a major control on the diversity and mode of emplacement of cave fossil deposits in eastern Brazil and thus detailed sedimentological and hydrological studies coupled with a sound geochronological approach are essential in quantifying the relative importance of each taphonomic processes before faunal and palaeoecological interpretations can be attempted

How much did climate force the Messinian salinity crisis? Quantified climatic conditions from pollen records in the Mediterranean region, 2006,
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Fauquette S, Suc Jp, Bertini A, Popescu Sm, Warny S, Bachiri Taoufiq N, Perez Villa Mj, Chikhi H, Feddi N, Subally D,
The latest Miocene (5.96 to 5.33[no-break space]Ma) is characterised by an outstanding event: the desiccation of the Mediterranean Sea (Messinian salinity crisis). It has been suggested that this was caused by a tectonic event, with no climatic change playing a role in desiccation. Quantifying the climate of the region during this period will help support or refute this hypothesis. An effective method for reconstructing the climate from Neogene pollen data is the 'Climatic Amplitude Method' based on the modern climatic requirements of plants to interpret fossil data. It has been conceived especially for periods devoid of modern vegetation analogue.Twenty Messinian to Lower Zanclean pollen sequences are now available in the peri-Mediterranean region. Most of them do not cover the whole Messinian interval, particularly those along the Mediterranean shorelines where sedimentation was interrupted during the sea's desiccation. In contrast, sedimentation was almost continuous in such areas as the Atlantic side of Morocco, along the Adriatic coast (including the Po Valley), and to a lesser extent the Black Sea. The Mediterranean sites nonetheless provide a reliable if not a discontinuous record of vegetation variability in time and space.A first examination of the pollen diagrams reveals a high regional variability controlled by local conditions, and throughout the interval a southward increase in herb pollen frequency in contrast to the tree pollen frequency. This indicates that open and probably dry environments existed in the southern Mediterranean region prior to, during and after the salinity crisis. Trees developed in areas close to mountains such as in the Po Valley, in Cerdanya and in the Black Sea region. Most variations observed in the pollen diagrams are constrained by fluctuations of Pinus pollen amounts, indicating eustatic variations. Climatic quantification from pollen data does not show obvious climatic changes due to the desiccation of the Mediterranean Sea, especially in the dry and warm southwestern Mediterranean area (Sicily, southern Spain and North Africa). At Maccarone, along the Adriatic Sea, a decrease in temperatures of the coldest month and, less importantly, a decrease in mean annual temperatures, corresponding to a drastic vegetation change, are reconstructed. These temperature variations are assumed to be controlled by regional environmental changes (massive arrival of waters in this basin) rather than to reflect cooling, because some authors link the second phase of evaporite deposition to a period of global warming. Some migrations of plants probably occurred as a response to Mediterranean desiccation. But the climatic contrast which has probably existed at that time between the central Mediterranean and the peripheral areas might be amplified.Climatic reconstruction from pollen data in the western Mediterranean area shows that climate is not the direct cause of the Mediterranean desiccation, as the Mediterranean region had experienced continuously high evaporation long before the crisis. Therefore the main factor leading to this event seems to be the successive closures of the Betic and Rifian corridors, isolating the Mediterranean Sea from the Atlantic Ocean

The Messinian salinity crisis in the Mediterranean basin: A reassessment of the data and an integrated scenario, 2006,
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Rouchy Jean Marie, Caruso Antonio,
After a long period of controversial debate about the interpretation of the Messinian salinity crisis (MSC), a near consensus existed since the ODP Leg 42A for a model keeping the major lines of the deep basin-shallow water model initially proposed by Hsu et al. (1973). The knowledge of the crisis was improved since the 1995s by the availability of a very accurate astronomically calibrated timescale. The debate about its interpretation was then reactivated by several new scenarios that questioned most the major aspects of the previous classical models. The updated re-examination of the most salient features along with consideration of the hydrological requirements for evaporite deposition allow us to assess the viability of the new models. We propose an integrated scenario that revives the key points of the previous model with new statements about the chronology, depositional settings, hydrological mechanisms, consequences and correlations with the global changes. A model implying two main stages of evaporite deposition that affected successively the whole basin with a slight diachronism matches better the whole dataset. The distribution of the evaporites and their depositional timing were constrained by the high degree of paleogeographical differentiation and by the threshold effects that governed the water exchanges. It is assumed that the central Sicilian basin was a deep basin located in a marginal position with regard to the deepest central basins. The restriction of the Mediterranean was predominantly under a tectonic control, but the complex development of the evaporitic crisis implied the interplay of both glacio-eustatic changes and fluctuations of the circum-Mediterranean climate.The first evaporitic stage (lower evaporites) that includes the deposition of the thick homogeneous halite unit with K-Mg salt interbeds in the deepest basins is correlated with the major evaporative drawdown and higher aridity, and occurred during the glacial period recorded in the ocean sediments between 6.3 and 5.6 Ma. The deposition of the potash in Sicily is tentatively linked to the two major glacial peaks TG 20 and TG 22, while the end of this first stage is linked to the peak TG 12. The second stage (upper evaporites) correlates with the interval of warming and global sea level rise recorded in the ocean since 5.6-5.5 Ma onwards. During this second stage, freshwater contribution increased and culminated by the latest Messinian dilution, i.e. the Lago-Mare event, as the result of the worsened tectonically driven closure of the Atlantic gateways combined to an evolution towards wetter climate conditions at least on the mountainous peripheral areas. In fact, reduced inputs of seawater continued to enter at least episodically the basin through the MSC explaining the sporadic presence of marine organisms. These inputs reached their lowest value and practically ceased during the latest Messinian dilution, just before the abrupt restoration of stable open marine conditions at the beginning of the Zanclean.A polyphased erosional surface affected the Mediterranean margins during the MSC with several critical episodes. The major episode related to the greatest water level fall, more than 1000 m, occurred during the deposition of the lower evaporites, from the onset of the evaporite deposition till the end of the first stage. Erosional processes remained active during the second evaporitic stage especially whenever the basin dried-up and a last important event marked by the karstification of the evaporites developed during the latest Messinian dilution just before the Early Zanclean reflooding that filled the erosional morphology

Extended Abstract: Ecology and hydrology of a threatened groundwater-dependent ecosystem: the Jewel Cave karst system in Western Australia, 2006,
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Eberhard, Stefan M.

This thesis investigates the hydrology and ecology of a threatened aquatic root mat community in the Jewel Cave karst system in the Leeuwin-Naturaliste Ridge, Western Australia. Development of the karst system dates from the Early Pleistocene and the caves have been available for colonisation by groundwater fauna since that time. Speleogenesis of the watertable maze caves occurred in a flank margin setting during earlier periods of wetter climate and/or elevated base levels. Watertable fluctuations over the last 50 years did not exceed the range experienced in the Quaternary history. The recent groundwater decline in Jewel Cave was not related to rainfall, nor groundwater abstraction nor nearby tree plantations. However, it did coincide with a reduction in fire frequency within the karst catchment. The resultant increase in understorey vegetation and ground litter may have reduced groundwater recharge through increased evapotranspiration and interception of rainfall. The populations of two genera and species of cave dwelling Amphipoda are largely panmictic. Both species have survived lower watertable levels during the Late Pleistocene. A mechanism for the colonization and isolation of populations in caves is proposed. Faunal patterns (including species diversity, species assemblages, habitat associations and biogeography) were related to abiotic environmental parameters. The ecological water requirements of the community were determined as a baseline for evaluation of impacts such as groundwater pollution. If rainfall continues to decline, and the cave watertable declines > 0.5 m below the present level, then the groundwater ecosystem may become more vulnerable to extinction. The taxonomy and distribution of root mat communities is poorly known and a regional-scale survey is required to properly assess their conservation requirements. Meanwhile, conservation actions for the communities need to be focused at the scale of the karst drainage system and catchment area.


CONTRIBUTION OF SIMPLE HYDROGEOLOGICAL INDICATING METHODS IN CONTAMINATION-IMPACTED ENVIRONMENTS, 2007,
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Mikita S. , Vybiral V.

Under the project of Ministry of the environment of Slovak Re­public a “real” impact of various contaminant sources on water was monitored and assessed during the period of 4 years. Vari­ous geological environments of The Western Carpathians were chosen as studying areas. The results of the project confirm that the influence of the contamination source is variable in space and time. An amount of objective and efficient information is necessary to fulfill the requirements for the water treatment. The possibility how to minimize the amount of expensive and intricate methods used by investigation was to connect them with hydrogeological indicating methods (HIM). The correlat­ed relations distinguished between contaminant and physical characteristics of water allow using the obtained local informa­tion in larger area and repeating them in higher frequency. The economical benefit is relative to increasing demands on space and time. The base was built on the water conductivity and wa­ter temperature measurements set in field. The measured values which were processed basically allow obtaining indirect infor­mation about the contamination spreading. By correlation the values with water analyses for a monitoring site from specific studied locality and by added other information from field methods the results can be amplified. It is possible to substitute the intricate and expensive contaminant spreading mapping methods by HIM and monitor the dynamic changes of contam­ination influences in space and time with denser data net.


INVESTIGATIONS REGARDING BEAR CAVE MASSIF (LOWER SILESIA) LONG-TERM STABILITy, 2008,
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M?kolski Krzysztof, Caco? Stefan Jamroz, Olgierd, Ko?k Blahoslav & Kacza?ek Miros?aw
Bear Cave under Mt nienik is located near the Lower Silesian Village of Kletno in a wider tectonic fault zone of Sudeten, Klodzko Valley, South Poland. Stability requirements along the visitors path in the cave called for permanent checks of possible rock movements in the massif, while mining operations in the neighbouring marble quarry represented major threat to cave stability. Precise levelling network for vertical movements in the cave and its vicinity was established about 20 years ago. Outside the cave in the Klenica River valley levelling traverses were crossing tectonic faults. Periodical measurements have been repeated since 1984. In the cave two fault zones of major risk have been checked also with TM-71 crack gauges and records have been taken with a month frequency. These two were the tectonic crack zones of the Water Corridor and the main fault structure of the cave found in the Cascade Alley. Fourteen years ago after finding that quarry blasts induced increased movements in the cave, quarry operations were stopped. Recently, gradual subsidence of some levelling bench-marks was observed, as well as some periods of increased micro-displacements on the tectonic crack zones. Such observations are discussed.

230Th/U-dating of fossil corals and speleothems, 2008,
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Scholz D. , Hoffmann D.

Both marine and terrestrial carbonates can be precisely dated by U-series disequilibrium methods in the age range <600 ka (thousands of years). Here we focus on 230Th/U-dating of reef corals and speleothems. The requirements, potential but also the problems of 230Th/U-dating of both archives are presented and discussed. Fossil reef corals are used as indicators for past sea level fluctuations and as high-resolution palaeoclimate archives. These applications require precise and accurate dating, which can be achieved using 230Th/U-dating. However, many fossil corals show evidence for post-depositional open-system behaviour. This limits the accuracy of 230Th/U-ages of fossil corals rather than the analytical precision. We present and discuss the currently available methods to identify altered corals and also review three recently developed open-system dating approaches. Speleothems are very important climate archives because they are found in most continental areas and can be used to investigate and directly compare spatially variable climate conditions. They usually show no evidence for open-system behaviour but may contain significant amounts of initial detrital 230Th. We discuss the currently available correction techniques and methods to derive the most reliable ages. Furthermore, we give an overview of the state of the art techniques for U-series isotopes measurements. 


Effectiveness and adequacy of well sampling using baited traps for monitoring the distribution and abundance of an aquatic subterranean isopod, 2009,
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Hutchins B. And Orndorff W.
Land-use practices in karst can threaten aquatic subterranean species (stygobionts). However, since their habitat is mostly inaccessible, baseline ecological data such as distribution and population size are not known, making monitoring and risk assessment difficult. Wells provide easy and inexpensive access for sampling subterranean aquatic habitats. Over three years, including a two-month period of intensive sampling, the authors sampled sixteen wells (ten repeatedly) in Jefferson County, West Virginia, USA, for a threatened stygobiont, the isopod crustacean Antrolana lira Bowman, in two areas where the species was known to occur. A. lira was collected during 21 of 54 sampling events. A. lira was collected from 6 wells in which a total of 31 of the sampling events took place. Borehole logs suggest that only these 6 wells intersected appropriate habitat. Using the binomial approximation, the authors conclude that a random well has a 29% to 91% chance of intersecting appropriate habitat. In a well that intersects appropriate habitat, a single sampling event has a 51% to 85% chance of successful capture. The species occurs heterogeneously throughout the aquifer both in space and time, and thus, repeated sampling of multiple wells is needed to confidently establish presence or absence. In a contiguous block of phreatic carbonate- aquifer habitat analogous to that in the study area, at least 6 wells need to be sampled at least one time each to determine absence or presence of A. lira with 95% confidence. Additional studies with larger sample size would better constrain confidence intervals and facilitate refinement of minimum sampling requirements. In one well that consistently yielded from 8 to 19 animals, the population was estimated by mark- recapture methods. The limited data only allowed a very rough result of 112.3 6 110 (95% CI) individuals. Successful recapture suggests that animals are largely stationary when a food source is present. Animals were collected at depths below the water surface from ,1m (hand-dug well and cave) to , 30 meters in drilled wells. No migration of animals between wells was observed.

Potential impact of a proposed railway tunnel on the karst environment: the example of Rosandra valley, Classical Karst Region, Italy-Slovenia, 2011,
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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.


The Mammalian Fauna of Abismo Iguatemi, Southeastern Brazil, 2011,
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Castro Mariela C. , Langer Max C.

The Quaternary vertebrate fauna record of South America is characterized by the predominance of mammals, and the study of cave deposits can provide important information on their diversity and distribution. In Brazil, cave deposits have preserved remarkable fossil remains, including both large and small vertebrates, although the former have been the focus of most paleontological works. The fossils studied here came from Abismo Iguatemi, a karstic fissure located in the municipality of Apiaı´, upper Ribeira River valley, Sa˜o Paulo, Brazil. Blocks of sediment collected from its floor yielded a large sample of micro-remains, mainly composed of fragmentary small vertebrate specimens. Taphonomic parameters suggest that the fossil elements entered the cave either by entrapment or transported by rain runoff, as partially decayed carcasses or isolated elements. A total of 35 taxa were recorded in Abismo Iguatemi, four of which are extinct. The number of identified specimens per taxon (NISP index) is the best estimator of number of individuals at the burial site. The comparison of this fauna to that of other Quaternary deposits and to the present biodiversity of different areas reveals low similarity. The identification of fossil organisms with different ecological requirements (extinct savannah organisms and extant dense-forest organisms) suggests the existence of time averaging and may reflect environmental changes in the vicinity of the cave during the late Pleistocene and Holocene


TOWARDS A KARST ASSESSMENT STANDARD PRACTICE, 2013,
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Denton, Jr. R. K.

The assessment of karst conditions and putative karst geohazards prior to residential and commercial development is currently in its infancy, from a scientific aspect. Borrowing from the medical lexicon, most karst features at proposed building sites are dealt with using an approach wherein the “symptoms and conditions” are treated (e.g. sinkhole remediation), often only after site development activities have commenced. If karst hazards are suspected, roadways, foundations and specific at-risk areas may be investigated using various geophysical methods; however the results of these investigations require specialized knowledge to be interpreted and understood. Thus stakeholders without geological training may find the investigator’s results indecipherable, often leading to unnecessary and expensive supplemental studies, the need for which is entirely based on the non-technical stakeholder’s faith in the investigator’s judgment.
In contrast, a recent trend among consulting firms is to attach cursory karst “assessments” to due diligence study reports, particularly Phase I Environmental Site Assessments. These combined assessments are often performed by individuals who are inexperienced in geology, often without any specific training in karst geology. Not unexpectedly, this can lead to numerous mistakes, errors, and oversights. More troubling, these studies often report a lack of karst risks at the site under study, a result that the stakeholders may initially embrace, but which later can result in substantial financial loss and/or significant threats to human health and the environment.
To address these concerns, we propose a proactive, “preventative” standard practice for karst assessments. Ideally, this proactive approach will help to delineate potential karst hazards so that they can be avoided, managed, or corrected by remediation. Requirements for investigators, a proposed scope of services, fieldwork and data review checklist, and a template for a follow-up karst management plan are presented. It is our hope that if carried out and reported accurately, the proposed assessments should allow even a non-technical stakeholder to make informed decisions regarding the relative risk of karst geohazards, the need for further studies, and potential corrective actions that site development may entail.


Karst water resources in a changing world: Review of hydrological modeling approaches, 2014,
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Karst regions represent 7–12% of the Earth’s continental area, and about one quarter of the global population is completely or partially dependent on drinking water from karst aquifers. Climate simulations project a strong increase in temperature and a decrease of precipitation in many karst regions in the world over the next decades. Despite this potentially bleak future, few studies specifically quantify the impact of climate change on karst water resources. This review provides an introduction to karst, its evolution, and its particular hydrological processes. We explore different conceptual models of karst systems and how they can be translated into numerical models of varying complexity and therefore varying data requirements and depths of process representation. We discuss limitations of current karst models and show that at the present state, we face a challenge in terms of data availability and information content of the available data. We conclude by providing new research directions to develop and evaluate better prediction models to address the most challenging problems of karst water resources management, including opportunities for data collection and for karst model applications at so far unprecedented scales


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