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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 dark adaptation is a change in the retina of the eye sensitizing it to dim light (the eye "becomes accustomed to the dark") [25]. compare light adaptation.?

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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 resistance (Keyword) returned 23 results for the whole karstbase:
Showing 1 to 15 of 23
Cavern Development in the Dimensions of Length and Breadth. PhD Thesis, 1982, Ewers, Ralph Owen

Three conceptual models are proposed for the integration of the large systems of conduits responsible for groundwater flow in soluble rocks. These models are supported by laboratory experiments with scaled solution models, flow-field analogues, and evidence from existing caves.
The three models reflect different boundary conditions imposed by geologic structure and stratigraphy. They have three characteristics in common. First, the smaller elements of the larger systems propagate separately from points of groundwater input toward points of discharge as distributary networks. Second, the integration of the smaller networks proceeds headward from the resurgence, in a stepwise fashion. Third, the result of the integration process in each case is a tributary system with many inputs discharging through a single discharge point.
The potential for growth of each of the smaller networks, within a common pressure field, is related to its distance from the discharge boundary and the distribution of other inputs. The first input to establish a low-resistance link to the discharge boundary will effect a localized depression within the potential field, thus attracting the flow and redirecting the growth of nearby networks until they eventually link with it. As additional orders of links develop, the system takes on a tributary pattern.
The first model applies to steeply dipping rocks. Inputs occur where bedding planes are truncated by erosion, and discharge takes place to the strike. Conduits in this case evolve as a roughly rectangular grid of strike and dip oriented elements. Dip elements are the initial form, with subsequent integration along the strike. The type example is the Holloch in Switzerland.
The second model applies to flat-lying rocks. Inputs occur over a broad area, and discharge takes place along a linear boundary. Conduits in this case evolve in a trellised array with elements normal to the discharge boundary predating those parallel to it. These latter conduits integrate the flow. The type example is the Mammoth Cave Region, Kentucky.
The third model applies to simple systems which occur beneath an impermeable cap rock. Inputs occur where erosion has breached the capping beds. The type example is Cave Creek, Kentucky.


Cave Detection using Electrical Resistance Tomography, 1992, Noel M. , Xu Biwen

EARLY DEVELOPMENT OF KARST SYSTEMS .1. PREFERENTIAL FLOW PATH ENLARGEMENT UNDER LAMINAR-FLOW, 1994, Groves C. G. , Howard A. D. ,
Modeling of flow and solutional processes within networks of interconnected conduits in limestone aquifers indicates that enlargement occurs very selectively during the early stages of karst aquifer development under laminar flow. If initial flow paths are uniform in size, almost all enlargement occurs along a single set of connected conduits that lie along a direct path between recharge and discharge locations and are aligned along the hydraulic gradient. With a sufficiently large variation in initial aperture widths, enlargement occurs along the flow path offering the least resistance to flow, but since flow rates in laminar flow are proportional to the fourth power of diameter but only linearly proportional to hydraulic gradient, the preferentially enlarged set of fractures may follow an indirect path. Results disfavor earlier suggestions that nonselective cave patterns result from artesian flows (at least under laminar flow conditions) and that all passages should be competitive until the onset of turbulent flow

Forest recovery in the karst region of Puerto Rico, 1998, Rivera L. W. , Aide T. M. ,
Widespread deforestation has led to an increase in secondary forest in the tropics. During the late 1940s in Puerto Rico, forest covered only 6% of the island, but a shift from agriculture to industry has led to the increase of secondary forest. This study focuses on the regeneration of forest following the abandonment of pastures and coffee plantations located in the karst region of Puerto Rico. Alluvial terraces and sinkholes were the principal features used for pastures, shifting agriculture, and coffee plantations, whereas mogotes (limestone hills of conical shape) were burned periodically or cut for charcoal or wood production. Abandoned pasture sites had a greater woody species diversity in comparison with coffee sites. The density of woody stems was greater in the abandoned pasture sites and Spathodea campanulata was the dominant species. In coffee sites Guarea guidonia was the most abundant species. There was no difference in basal area between the two land uses. Canonical Correspondence Analysis applied separately to adults and seedlings clearly separated each community according to land use. Seedling composition in coffee sites indicates a resistance to change in terms of the dominant species while in the pasture sites the composition will change as the dominant species S. campanulata is replaced with more shade tolerant species. Patches of forest that remained on the steep sides of mogotes and the presence of bats appears to have enhanced forest recovery, but the land use history of these sites has affected the pattern of regeneration and will continue to affect forest dynamics for many years. The karst area is a critical environment for water resources and biodiversity and its conservation and restoration is essential. (C) 1998 Elsevier Science B.V. All rights reserved

Geoecological studies on the karstic surfaces of the planned Protected Area in Western Mecsek, South Hungary, 1999, Hoyk, Edit

Earlier studies on the karst in Western Mecsek have already shown that this area is worth protection due to its quite well preserved natural state. In consequence, declaring the karstic territory with its wider environment as a protected area is being considered in the Danube-Drava Natural Park. In order to prove the almost untouched natural state of an area good starting point is to examine its soil and flora. Soil studies focus on determining the pH, detecting any tendency of a shift towards lower pH values and on examining the carbonate content. In the future measurements to check the heavy metal content that are especially suitable for showing the levels of anthropogenic contamination will be added to these studies. Investigations on the flora based on the examination of water balance, soil reaction and determination of the rank according to the categories of nature conservation value offer a support to the claim of being protected. The results show that indirect anthropogenic effects can be detected by the pH shift towards lower values, but the same tendency of turning acidic is less characteristic in dolines which are the most sensitive points of karstic fields. However, the relatively high carbonate content favours the resistance against felling pH values. Examining the vegetation, and paying special attention to the ranking into nature conservation categories, a significantly high ratio of association - forming and accompanying species and the presence of protected species in relatively high numbers can be seen that proves the nature conserving feature of the territory. On the basis of the investigations carried out the maintenance of the present state of the territory is a desirable objective and in order to realize it the protection of the area is absolutely justified.


Conduit fragmentation, cave patterns, and the localization of karst ground water basins: the Appalachians as a test case., 2001, White W. B. , White E. L.
Because conduit systems in maturely developed karst aquifers have a low hydraulic resistance, aquifers drain easily and karst aquifers are subdivided into well-defined ground water basins. Ground water elevations arc highest at basin boundaries; lowest at the spring where the ground water is discharged. Parameters that control the type of conduit development are (1) the effective hydraulic gradient, (2) the focus of the drainage basin, and (3) the karstifiability of the bedrock. Moderate to highly effective hydraulic gradients permit the runaway process that leads to single conduit caves and well ordered branchwork systems. Low hydraulic gradients allow many alternate flow paths and thus a large degree of fuzziness in the basin boundaries. Low gradient ground water basins also tend to merge due to rising water tables during periods of high discharge. Focus is provided by geological constraints that optimize discharge at specific locations that can evolve into karst springs. Karstifiability is a measure of the bulk rate at which aquifer rocks will dissolve. Fine grained, pure limestones and shaley dolomites mark the opposite ends of the range. The cave surveys of the Appalachian Highlands provide a data base that can be used to classify the lateral arrangements of conduit systems and thus determine the relative importance of the factors defined above.

Altered lignin structure and resistance to pathogens in spi 2-expressing tobacco plants, 2002, Elfstrand M, Sitbon F, Lapierre C, Bottin A, Von Arnold S,

Conduit fragmentation, cave patterns, and the localization of karst ground water basins: the Appalachians as a test case, 2003, White W. B. , White E. L.

Because conduit systems in maturely developed karst aquifers have a low hydraulic resistance, aquifers drain easily and karst aquifers are subdivided into well-defined ground water basins. Ground water elevations are highest at basin boundaries; lowest at the spring where the ground water is discharged. Parameters that control the type of conduit development are (1) the effective hydraulic gradient, (2) the focus of the drainage basin, and (3) the karstifiability of the bedrock. Moderate to highly effective hydraulic gradients permit the runaway process that leads to single conduit caves and well ordered branchwork systems. Low hydraulic gradients allow many alternate flow paths and thus a large degree of fuzziness in the basin boundaries. Low gradient ground water basins also tend to merge due to rising water tables during periods of high discharge. Focus is provided by geological constraints that optimize discharge at specific locations that can evolve into karst springs. Karstifiability is a measure of the bulk rate at which aquifer rocks will dissolve. Fine grained, pure limestones and shaley dolomites mark the opposite ends of the range. The cave surveys of the Appalachian Highlands provide a data base that can be used to classify the lateral arrangements of conduit systems and thus determine the relative importance of the factors defined above.


Testing for reach-scale adjustments of hydraulic variables to soluble and insoluble strata: Buckeye Creek and Greenbrier River, West Virginia, 2003, Springer G. S. , Wohl E. E. , Foster J. A. , Boyer D. G. ,
An open question exists as to whether channel geometries and hydraulics are adjusted in bedrock streams with stable, concave profiles in a manner analogous to alluvial rivers. As a test of this problem, a comparison was undertaken of channel geometries and hydraulics among reaches with substrates that are of high mechanical resistance, but of variable chemical resistance. Reaches were selected from Buckeye Creek and Greenbrier River, West Virginia, USA because these streams flow over sandstones, limestones, and shales. The limestones have Selby rock resistance scores similar to those of the sandstones. A total of 13 reaches consisting of between 6 and 26 cross sections were surveyed in the streams. HEC-RAS was used to estimate unit stream power (omega) and shear stress (tau) for each reach. The reaches were selected to evaluate the null hypothesis that that omega and tau are equal atop soluble versus insoluble bedrock. Hypothesis tests consisted of paired t-tests and simultaneous, multiple comparisons. Geomorphic setting was included for Greenbrier River because previous studies have suggested that bedrock streams are intimately coupled with hillslopes. Holding geomorphic setting constant, three separate comparisons of omega and tau reveal that these variables are lowest atop soluble substrates in Greenbrier River (significance less than or equal to 0.05) and that changes in and tau are mediated by changes in channel geometry. Similarly, headwater reaches of Buckeye Creek developed atop shale and sandstone boulders are statistically distinguishable from downstream reaches wherein corrosion of limestone is the primary means of incision. However, comparisons in each stream reveal that channel geometries, omega and tau, are not strictly controlled by bed solubility. For constant substrate solubility along the Greenbrier River, omega and tau are consistently higher where a bedrock cutbank is present or coarse, insoluble sediment enters the channel. The latter is also associated with locally high values of omega and tau in Buckeye Creek. Assuming that incision by corrosion requires lower values of omega and tau because the channel need not be adjusted for block detachment and tool acceleration, we posit that the statistically lower values of omega and tau are tentative evidence in favor of differential geometric and hydraulic adjustments to substrate resistance. We observe that these adjustments are not made independent of geomorphic setting. (C) 2003 Elsevier Science B.V. All rights reserved

Simulation of the development of karst aquifers using a coupled continuum pipe flow model - art. no. 1057, 2003, Liedl R. , Sauter M. , Huckinghaus D. , Clemens T. , Teutsch G. ,
[1] This paper is intended to provide insight into the controlling mechanisms of karst genesis based on an advanced modeling approach covering the characteristic hydraulics in karst systems, the dissolution kinetics, and the associated temporal decrease in flow resistance. Karst water hydraulics is strongly governed by the interaction between a highly conductive low storage conduit network and a low-conductive high-storage rock matrix under variable boundary conditions. Only if this coupling of flow mechanisms is considered can an appropriate representation of other relevant processes be achieved, e.g., carbonate dissolution, transport of dissolved solids, and limited groundwater recharge. Here a parameter study performed with the numerical model Carbonate Aquifer Void Evolution (CAVE) is presented, which allows the simulation of the genesis of karst aquifers during geologic time periods. CAVE integrates several important features relevant for different scenarios of karst evolution: (1) the complex hydraulic interplay between flow in the karst conduits and in the small fissures of the rock matrix, (2) laminar as well as turbulent flow conditions, (3) time-dependent and nonuniform recharge to both flow systems, (4) the widening of the conduits accounting for appropriate physicochemical relationships governing calcite dissolution kinetics. This is achieved by predefining an initial network of karst conduits ('protoconduits'') which are allowed to grow according to the amount of aggressive water available due to hydraulic boundary conditions. The increase in conduit transmissivity is associated with an increase in conduit diameters while the conductivity of the fissured system is assumed to be constant in time. The importance of various parameters controlling karst genesis is demonstrated in a parameter study covering the recharge distribution, the upgradient boundary conditions for the conduit system, and the hydraulic coupling between the conduit network and the rock matrix. In particular, it is shown that conduit diameters increase in downgradient or upgradient direction depending on the spatial distribution (local versus uniform) of the recharge component which directly enters the conduit system

Hydraulic Resistance of Different-Type River Channels with Manifestations of Karst and Suffosion Processes, 2003, Antropovskii Vi,

Comparative estimate of resistance to drought for selected karstic aquifers in Bulgaria, 2004, Orehova Tatiana
Effective management of water resources requires adequate knowledge of groundwater system including the influence of climate variability and climate change. The drought of 1982-1994 in Bulgaria has led to important decrease of springflow and lowering of water levels. Therefore, groundwater demonstrated its vulnerability to drought. The purpose of this paper is to determine relative resistance of selected aquifers in Bulgaria to a prolonged decrease of recharge to groundwater. The drought resistance indicator has been defined for some karstic aquifers based on the method proposed in report of BRGM. The data from National Hydrogeological Network located in the National Institute of Meteorology and Hydrology were processed. For the aim of this study, time-series of discharge for karstic springs were used. Stations with significant impact of human activity on groundwater were eliminated. The results show that most of studied aquifers in Bulgaria have moderate and weak resistance to the drought. They are vulnerable to droughts and need good management for effective use of groundwater resources.

Current issues and uncertainties in the measurement and modelling of air-vegetation exchange and within-plant processing of POPs, 2004, Barber Jl, Thomas Go, Kerstiens G, Jones Kc,
Air-vegetation exchange of POPs is an important process controlling the entry of POPs into terrestrial food chains, and may also have a significant effect on the global movement of these compounds. Many factors affect the air-vegetation transfer including: the physicochemical properties of the compounds of interest; environmental factors such as temperature, wind speed, humidity and light conditions; and plant characteristics such as functional type, leaf surface area, cuticular structure, and leaf longevity. The purpose of this review is to quantify the effects these differences might have on air/plant exchange of POPs, and to point out the major gaps in the knowledge of this subject that require further research. Uptake mechanisms are complicated, with the role of each factor in controlling partitioning, fate and behaviour process still not fully understood. Consequently, current models of air-vegetation exchange do not incorporate variability in these factors, with the exception of temperature. These models instead rely on using average values for a number of environmental factors (e.g. plant lipid content, surface area), ignoring the large variations in these values. The available models suggest that boundary layer conductance is of key importance in the uptake of POPs, although large uncertainties in the cuticular pathway prevents confirmation of this with any degree of certainty, and experimental data seems to show plant-side resistance to be important. Models are usually based on the assumption that POP uptake occurs through the lipophilic cuticle which covers aerial surfaces of plants. However, some authors have recently attached greater importance to the stomatal route of entry into the leaf for gas phase compounds. There is a need for greater mechanistic understanding of air-plant exchange and the 'scaling' of factors affecting it. The review also suggests a number of key variables that researchers should measure in their experiments to allow comparisons to be made between studies in order to improve our understanding of what causes any differences in measured data between sites. (C) 2003 Elsevier Ltd. All rights reserved

River backflooding into a karst resurgence (Loiret, France), 2004, Alberic P,
The group of springs located in the west part of the Val d'Orleans exemplifies a type of karstic emergence which has the particularity to get most of its recharge water from a single surface water source, which in this particular case is the River Loire. Hence the flow of this group of springs is known to fluctuate in a close relationship with the water level of the River Loire. Since the second half of the 1990s, the conduit of the upstream spring of the Loiret river (so-called Le Bouillon) has been periodically seen to be invaded by the turbid waters of a small surface tributary (Le Dhuy) flowing back from the confluence to the spring, which then functioned as a swallow-hole. Plotted in a Dhuy versus River Loire diagram, stages of backflooding days describe a domain limited by a curve of the form HDhuy = c e((aH Loire)). The exponential form of the relation corresponds to the increasing resistance of the emerging flow of the spring to the backflooding of the tributary waters, as the River Loire stages rise. The equation above was used to compute a daily backflow index enabling the effective reconstruction of all occurrences effectively counted during the regular period of observation of the spring. Extended to 1985, one can observe that the early 1990s do not appear as a favorable period to backflow events but some may have occurred during the years 1986 to 1989. The observation of rainfall intensity preceding backflooding shows that in a short time span there is no necessity to evoke intrinsic changes inside the Val d'Orleans basin to explain what might appear as a troublesome new phenomenon. In conclusion backflooding has probably existed for a long time and is simply under the control of local heavy rainfall during low River Loire stages. (C) 2003 Elsevier B.V. All rights reserved

Rock coast morphology in relation to lithology and wave exposure, Lord Howe Island, southwest Pacific, 2005, Dickson Me, Woodroffe Cd,
The morphology of rock coastlines appears primarily to be a function of the eroding force of waves and the resistance of rocks, but a number of local factors complicate determination of the relative significance of these as opposed to other factors. Lord Howe Island, a small, basaltic mid-oceanic island in the northern Tasman Sea, presents a unique opportunity to differentiate the roles of rock resistance and wave exposure. The island occurs at the southern limit of coral growth and there is a fringing coral reef and lagoon on a portion of the western coastline. The reef markedly attenuates wave energy and there is an impressive contrast between the sheltered lagoonal coastline, which consists largely of depositional sandy beaches and vegetated hillslopes, and the exposed coastline which is bold and rugged having been eroded by waves into precipitous plunging cliffs, cliffs with talus slopes, and cliffs with basal shore platforms. There is a clear contrast between the development of basalt shore platforms along the sheltered and exposed coastlines: exposed platforms are wider, backed by a higher and steeper cliff, and are without talus deposits, as opposed to sheltered platforms that are veneered by talus. Calcarenites, deposited in the Late Pleistocene, hence precluding significant rock coast inheritance, have been eroded into platforms that are approximately twice as wide on the exposed coastline than the sheltered coastline. Further evidence as to the efficacy of wave erosion around Lord Howe Island is provided by a suite of landforms that appear to have developed as a result of localised wave-quarrying of highly jointed dykes (sea caves, arches, blowholes, and gulches)

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