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Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

Speleology in Kazakhstan

Shakalov on 11 Jul, 2012
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

New publications on hypogene speleogenesis

Klimchouk on 26 Mar, 2012
Dear Colleagues, This is to draw your attention to several recent publications added to KarstBase, relevant to hypogenic karst/speleogenesis: Corrosion of limestone tablets in sulfidic ground-water: measurements and speleogenetic implications Galdenzi,

The deepest terrestrial animal

Klimchouk on 23 Feb, 2012
A recent publication of Spanish researchers describes the biology of Krubera Cave, including the deepest terrestrial animal ever found: Jordana, Rafael; Baquero, Enrique; Reboleira, Sofía and Sendra, Alberto. ...

Caves - landscapes without light

akop on 05 Feb, 2012
Exhibition dedicated to caves is taking place in the Vienna Natural History Museum   The exhibition at the Natural History Museum presents the surprising variety of caves and cave formations such as stalactites and various crystals. ...

Did you know?

That cooling water is water used only for cooling purposes [16].?

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.
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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 variance (Keyword) returned 20 results for the whole karstbase:
Showing 1 to 15 of 20
Diversity and dynamics of microarthropods from different biotopes of Las Sardinas cave (Mexico) , , Jos Palaciosvargas, Gabriela Castaomeneses, Daniel A. Estrada

An ecological study of the microarthropod communities from Las Sardinas cave was undertaken. Four different biotopes were studied over the course of a year: bat guano, litter, soil under the chemoautotrophic bacteria colonies and as a control, plain soil without litter or guano. A total of 27,913 specimens of a total of 169 species were collected. Analysis of Variance (ANOVA) showed that there is a significant effect of biotope on the recorded density, and the post hoc Tukey’s test showed that guano is the most different biotope with the highest value of density recorded. The interaction between season and biotope variables was not significant. In the most extreme case, 99 percent of the microarthropods in soil under chemoautotrophic bacteria were mites, mainly in the family Histiostomidae.

Ecological and biogeographical trends in Harpacticoids., 1976, Jakobi Hans
The majority of harpacticoids show a great dependence on the peculiarities of their habitat. This research attempted to detect the possible existence of biogeographical and ecological trends. The limited biogeographical data is discussed, so this is applied the method of analysis of morpho-ecological correlation (Jakobi, 1962) developed to determine ecological trends. This way, all characteristics of the harpacticoidean body selected were studied to check their adaptative value. Based on those results it was possible to establish and to define ecological units. Data were then subjected to statistical tests of homogeneity for variance and significance. Graphs are used to demonstrate the natural adaptation process. Diagrams permit one to recognize the general tendencies as well as degrees of specific evolution. Nevertheless, quite different principles such as type formation and atomic orbit model analogy, were applied to understand biogeographic trends. The change of the endopodits of the 4th leg of adult males (Enp. P4 male) is utilized as an example.

Some Implications of Competition for Cave Stream Communities., 1981, Culver David C.
Based on recent theoretical work by Robert May and Richard Levins, two hypotheses about time fluctuations in abundance of competing species were generated. Data for isopods and amphipods from four cave stream communities in Virginia and West Virginia were used to test the predictions. First, variance of total abundance should be less than the sum of the variances of individual species' abundances. In three of four communities studied, the prediction was confirmed, but none were statistically significant. Positive correlations among carrying capacities of competing species may explain the poor agreement with predictions. Second, the signs of 19 correlations and partial correlations of species abundances were predicted on the basis of relative magnitudes of direct and indirect effects of competition, and of these predictions, 16 were confirmed by the data, including 5 statistically significant ones. Most interesting was the finding that competitors can be positively correlated.

Double Fourier series models of two doline and two cockpit landscapes in northern Jamaica, each 2 x 2 km in area, explained 92% and 90%, and 73% and 58% of the variance in the topographic data. The ten most significant waves accounted for 74% and 76%, and 61% and 58% of the variance in each model. The greater importance of frequency pairs of longer wavelength in the doline karst models suggests that there are fewer horizontally and vertically persistent bedrock fractures controlling topographic development in the doline areas than in the cockpit terrains-a fact confirmed by fracture-trace mapping. Frequency pair orientations and powers indicate that northwest- and northeast-trending fractures exert a major influence on topographic development in the cockpit terrains and that east-trending fractures are relatively more important in the doline areas. Further studies are needed to determine if Fourier models of the doline, cockpit, and tower karst styles differ in a consistent fashion and to find out to what extent these differences are related to the bedding, fracture, and relief characteristics of the karst bedrock

GEOCHEMICAL MAPPING OF CARBONATE TERRAINS, 1991, Pirc S. , Mcneal J. M. , Lenarcic T. , Prohic E. , Svrkota R. ,
Surface drainage samples, the usual media employed in mapping national territories, cannot be used for the geochemical mapping of carbonate terrains because of the absence of a regular surface-drainage pattern on karst. Suitable sampling media have been studied in Yugoslavia, one-third of which consists of karst terrain. Sampling designs for the work were based on analysis of variance techniques. During initial investigations of various sampling materials in northwest Yugoslavia sediment and aquatic moss from karst springs, along with soil, were established as the most appropriate media. Modified sampling procedures were then carefully applied along the entire Yugoslav karst belt, which includes terrains of contrasting topography, climate, pedology and vegetation. The studies indicate that climate and relief do not systematically influence the geochemical composition of soil. Regional and local variability was assessed for 21 chemical elements and the feasibility of producing stable regional geochemical maps was determined for a number of elements on the basis of sampling aquatic moss and sediment from karst springs and soil

Karst hydrogeology of the Canadian Rocky Mountains, PhD Thesis, 1991, Worthington, Stephen Richard Hurst

An analysis of the discharge and hydrochemical variations of contrasting springs at Crowsnest Pass showed they were part of a vertical hierarchy in the aquifer, in which underflow and overflow components play a dominant role. It was found that karst springs at Crowsnest Pass and elsewhere show a range between two end members. Thermal springs have long, deep flow paths, with high sulphate concentrations, low discharge variance and low flow velocities. Overflow springs have local shallow flow paths, low sulphate, high discharge variance, and high flow velocities. Intermediate between these end members are underflow springs; in the Rocky Mountains these are mostly aggraded, and give the sustained winter flow and high sulphate concentrations found in major rivers. It was found that underflow or overflow behaviour is able to explain most of the contrasts found between karst springs in discharge and sulphate concentrations. Conversely, differences in bicarbonate concentration are principally due to the ratio of allogenic to autogenic recharge to the aquifer. Hydraulic analysis showed that gradients decrease in the downstream direction, and are typically 0.0001-0.05 at maximum discharges, that friction factors vary by a factor of $>$1000, and that most active conduits have closed-channel flow and are in dynamic equilibrium with sediment supply. The analysis of the hydrological data from Crowsnest Pass and elsewhere has led to the development of a new conceptual model for groundwater flow in karst, in which the Hagen-Poiseuille flow net conditions the aquifer for conduit development, and determines where the conduits will be. The model explains why most conduits are in dynamic equilibrium with sediment supply, why temperate karst springs are mostly vauclusian, what the mean time for speleogenesis is, how $>$98% of the solution of limestone is in the surficial zone, and why there are karstic hot springs in the Rocky Mountains and elsewhere. The model enables predictions to be made of sink to resurgence flow velocities, of conduit depth below the water table, of the ratio of beds to joints used by conduits, of the spacing between cave tiers, and of the depth of vauclusian springs. This new understanding of how karstic aquifers develop and function gives a powerful predictive ability to karst hydrogeology.

Counter to intuition, small-scale measurements of hydraulic conductivity do not average to regional values. Instead, mean hydraulic conductivity increases with measurement scale up to a critical distance termed the range, beyond which a constant regional value prevails. Likewise, variance in log hydraulic conductivity increases with separation distance between measurement points as the spatial correlation decreases. As dissolution proceeds in carbonate aquifers, heterogeneity and the volume necessary for an equivalent homogeneous medium (EHM) both increase. As these variables increase, the range of scale increase in both mean hydraulic conductivity and variance increases proportionately. Consequently, the range in scale effects is a reliable measure of the degree of secondary dissolution. By correlating the numeric value of range with independently measured hydraulic properties, the prevalent type of flow system, diffuse, mixed or conduit can be determined

PC-based two-dimensional discrete Fourier transform programs for terrain analysis, 1996, Harrison J. M. , Lo C. P. ,
A two-dimensional Fast Fourier Transform (2D-FFT) program written in C language was developed for the personal computer with the specific purpose of extracting periodicities from digital elevation model (DEM) data. The program generates the individual frequency pairs, the coefficients representing the amplitudes of the cosine and sine waves, the angle the wavefront makes in the terrain, the wavelength, the power of the wave, the percent contribution the wave makes to the overall landscape, and finally the overall percentage of variance accounted for by the model. The landscape can be reconstructed based on the number of significant waveforms extracted. Generalizations on the spatial trends of the terrain therefore can be made. The Fourier analysis provides insight to the nature and complexity of the terrain. An application of the program to the karst landscape of Manati, Puerto Rico is illustrated. Copyright (C) 1996 Elsevier Science Ltd

Distribution Map of Caves and Cave Animals in the United States, 1999, Culver, D. C. , Hobbsiii, H. H. , Christman, M. C. , Master, L. L.
The distributions of nearly 45,000 caves and 924 obligate cave species and subspecies (stygobites and troglobites) in the 48 contiguous states of the United States were mapped by county. Both maps show a highly clumped distribution. Approximately one-half of the variance in the number of species in a county is explained by variance in the number of caves per county.

The Vazante zinc mine, Minas Gerais, Brazil; constraints in willemitic mineralization and fluid evolution, 1999, Lena Virginia Soares Monteiro, Jorge Silva Bettencourt, Baruch Spiro, Rodnei Graca, And Tolentino Flavio De Oliveira
The Vazante Mine is located in the Vazante District, the largest zinc district in Brazil. The Vazante deposit consists dominantly of an unusual willemitic ore. Small sulfide bodies are tectonically imbricated with the willemitic ore, within the Vazante shear zone. Structural styles of deformation and petrographic and isotopic evidence indicate that willemitic mineralization and deformation occurred synchronously during the Neo-Proterozoic. Various generations of hydrothermal veins and hydraulic breccias may pre-date, accompany and overprint the mineralization. Ore-formation temperatures are deduced from stable isotope geothermometry and mineral chemistry of both sulfide bodies and willemitic ore. Temperatures during the main stage of mineralization range from 206 degrees C to 294 degrees C (willemitic ore) and 317 degrees C (sulfides), and reflect the prevailing metamorphic conditions within the shear zone. The fluid from which the gangue minerals of the sulfide bodies precipitated (at 250 degrees C) had an oxygen isotopic average value of delta 18 O = +19.4 per mil. This value appears to reflect the interaction of metamorphic fluid with the carbonate rocks of the Vazante formation. At 250 degrees C, the fluid in equilibrium with the vein mineral phases and willemitic ore assemblage exhibits a uniform oxygen isotopic composition, with an average value of delta 18 O = +11.5 per mil. The positive linear covariance of delta 18 O and delta 13 C ratios of the carbonates is most likely due to the mixing of metamorphic and meteoric fluids. The delta 34 S values of sulfides indicate a direct crustal origin for the sulfur. It is suggested that the sulfur is largely derived from pre-existing sulfide bodies and has been transported by metamorphic fluids. The willemitic ore may have originated from the precipitation of metal in sulfur-poor fluids under oxidized conditions, within the Vazante shear zone.

Forecasting of turbid floods in a coastal, chalk karstic drain using an artificial neural network, 2001, Beaudeau P, Leboulanger T, Lacroix M, Hanneton S, Wang Hq,
Water collected at the Yport (eastern Normandy, France) Drinking Water Supply well, situated on a karst cavity, is affected by surface runoff-related turbidity spikes that occur mainly in winter, In order to forecast turbidity, precipitation was measured at the center of the catchment basin over two years, while water level and turbidity were monitored at the web site. Application of the approach of Box and Jenkins (1976) leads to a linear model that can accurately predict major floods about eight hours in advance, providing an estimate of turbidity variation on the basis of precipitation and mater level variation over the previous 24 hours. However, this model is intrinsically unable to deal with (1) nonstationary changes in the time process caused by seasonal variations of in ground surface characteristics or tidal influence within the downstream past of the aquifer, and (2) nonlinear phenomena such as the threshold for the onset of runoff. This results in many false-positive signals of turbidity in summer. Here we present an alternative composite model combining a conceptual runoff submodel with a feedforward artificial neural network (ANN), This composite model allows us to deal with meaningful variables, the actioneffect of which on turbidity is complex, nonlinear, temporally variable and often poorly described. Predictions are markedly improved, i.e,, the variance of the target variable explained by 12-hour forward predictions increases from 28% to 74% and summer inaccuracies are considerably lowered. The ANN can adjust itself to new hydrological conditions, provided that on-line learning is maintained

Quantification of Macroscopic Subaerial Exposure Features in Carbonate Rocks, 2002, Budd Da, Gaswirth Sb, Oliver Wl,
The macroscopic features that characterize subaerial exposure surfaces in carbonates are well known, but their significance has not been quantitatively evaluated. This study presents such an analysis in the lower Oligocene Suwannee Limestone of west-central Florida. Eleven cores were point counted on a foot-by-foot basis for the abundance of caliche, rhizoliths, karst breccia, open vugs, infiltrated sediment, fractures, and pedogenic alteration. These features occur at and below intraformational exposure surfaces, which represent hiatuses estimated at 104 to 105 years, and an uppermost sequence-bounding unconformity representing 0.5 Myr, as revealed by Sr-isotope data. Statistical analyses of the point-count data reveal only a few significant relationships. (1) The hierarchy of exposure surfaces, and by inference duration of exposure, is differentiated only at a marginally significant level by sediment-filled vugs preferentially associated with the sequence boundary. Duration of exposure did not have a significant impact on the relative abundance of all other features. (2) Proximity (< 5 ft; 1.5 m) to any exposure surface is indicated only by rhizoliths, caliche, and pedogenic alteration, whereas karst breccia is preferentially found distal (> 5 ft) to both types of surfaces. Fractures, open vugs, and infiltrated sediment show no proximal or distal preference for either type of surface. (3) Depositional texture has no statistically significant affect on the presence or abundance of the exposure features, with the exception that rhizoliths and open vugs are preferentially more abundant in packstones relative to grainstones. This is interpreted to be the result of a soil-moisture effect. Factor analysis defines four factors that explain 46% to 52% of the total variance in the abundance data relative to the sequence boundary and the intraformational surfaces, respectively. The loading of each exposure feature on each factor is the same with respect to both types of surfaces, which is further evidence that the abundance of exposure features is independent of duration of exposure. Factor 1 is interpreted to be the amplitude of base-level changes and controls the abundance of karst breccia. Factor 2 is interpreted to be abundance of vegetation and relates to the abundance of rhizoliths and fractures. Factor 3 is interpreted to be a combination of soil-zone PCO2 and the availability of water and affects the abundance of pedogenic overprinting, caliche, and open vugs. Factor 4 is stratigraphic proximity to the sequence boundary, which controls the presence of sediment-filled voids. The amount of uncorrelated unique variance associated with infiltrated sediments, pedogenic overprinting, caliche, and open vugs is large (> 60%), meaning that feature abundance is also influenced by other unidentified site-specific factors. These results demonstrate that quantifying the abundance of macroscopic subaerial exposure features in limestones has the potential to yield more insight into the significance of those features than a mere qualitative assessment. This is particularly true when assessing the potential role of the many variables that can affect the development of these features

The vegetation of the high mountains of Crete - a revision and multivariate analysis, 2002, Bergmeier E,
The vegetation at elevations above 1,400 m in the south Aegean island of Crete (Greece) is studied and revised. By means of phytosociological classification (assisted by TWINSPAN) and ordination (Detrended correspondence analysis, DCA), the plant communities and abiotic (environmental, geographical) factors governing the variance in vegetation are described and discussed. The analyses are based on 492 sample plots from the three major mountain ranges of Crete. All published data available, as well as own unpublished releves are included. Since the plots differ much with respect to species number and plot size, and to combine different subsets and different data properties, various data sets are used for DCA ordination. Data on environmental variables are used supplementarily. Ordination results suggest the following factors to be of major effect on the variance in vegetation: Rock type, soil type, altitude, geographical situation, degree of substrate fixation, and inclination. The representation of local and regional endemics in the vegetation increases with altitude and along the habitat type series: phrygana and woodland - fixed slopes - dolines - screes. A synoptic table of 26 columns (vegetation types and subtypes) is presented. The vegetation consists of the tragacanth formation of fixed slopes (8 columns), swards and scrub of doline grounds (9), scree vegetation (4), and rupicolous chasmophytic vegetation (2). Phrygana (2) and woodland vegetation (1) are marginal. A hierarchical conspectus of the syntaxa is provided which includes the following nomenclaturally relevant new or validated names of various ranks (in alphabetic order): Alysso sphaciotici-Valantion apricae, Arenario fragillimae-Silenetum antri-jovis, Arenarion creticae, Astragalion cretici, Berberido creticae-Astragaletum cretici, Cicero incisi-Silenetum variegatae, Colchico cretensis-Cirsion morinifolii, Fumano paphlagonicae-Helianthemetum hymettii, Gypsophilo nanae-Arenarietum creticae, Hyperico kelleri-Anchusetum cespitosae, Lomelosio sphacioticae-Centranthetum sieberi, Paronychio macrosepalae-Juniperetum oxycedri, Saturejo spinosae-Scutella-rietalia hirtae, Sideritido syriacae-Verbascetum spinosi, Verbascion spinosi

Landscape Evolution and Cave Development in Response to Episodic Incision of the Cumberland River, Tennessee and Kentucky, USA., 2003, Anthony, Darlene M. Ph. D.

Episodic incision punctuated by periods of base level stability during the Plio-Pleistocene left the Upper Cumberland River in Tennessee and Kentucky deeply entrenched into the unglaciated Appalachian Plateaus. The relative chronology of episodic river incision and base level stability is well documented thanks to over a century of careful mapping of upland surfaces, inset straths, and terrace gravels. Constraining the timing of these incision events has been difficult, however, primarily due to a lack of suitable dating methods for terrace materials ranging from several hundred thousand to several million years of age, and reworking of upland gravels onto lower terraces. These problems are solved by dating the burial age of undisturbed cave sediments in place of terrace deposits, using the differential decay of cosmogenic 26Al and 10Be in quartz exposed to cosmic radiation at the surface. This study offers a new chronology of river incision beginning with initial incision into the Highland Rim after ~3.5 Ma; development of the Parker strath between ~3.5 and ~2 Ma; incision of the Parker strath at ~2 Ma; development of a major terrace beneath the Parker strath between ~2 and ~1.5 Ma; incision into this terrace at ~1.3 Ma; and the development of several discontinuous terraces above the modern flood plain between ~1.3 Ma and the present.
Large caves on tributaries of the Upper Cumberland River record a headward wave of incision in the Pliocene and Early Pleistocene. The passage of a knickpoint in the system is modeled as a perturbation to steady-state incision according to the stream power law, which is tested against the abandonment dates in seven caves. Model results for m/n = 0.68 are within previously published theoretical and empirical values of 0.5 to 1.0, but suggest that values for the drainage-area exponent m are several times higher
than previous studies. This may be caused by a stronger variance of discharge to drainage area in fluviokarst reaches compared with non-karst watersheds. Knickpoint migration rates in limestone bedrock channels of fluviokarst tributaries to the Cumberland River are calculated between 10-18 cm/year during the Plio-Pleistocene, with m = 1.91 and m/n = 0.79.

Geochemistry of red residua underlying dolomites in karst terrains of Yunnan-Guizhou Plateau II. The mobility of rare earth elements during weathering, 2004, Ji H. B. , Wang S. J. , Ouyang Z. Y. , Zhang S. , Sun C. X. , Liu X. M. , Zhou D. Q. ,
The aim of this study is to characterize the evolution of the rare earth elements (REE) in the Pingba red residua on karst terrain of Yunnan-Guizhou Plateau. The in-situ weathering and the two-stage development of the profile had been inferred from REE criterions. The REE were significantly fractionated, and Ce was less mobilized and separated from the other REEs at the highly enriched top of the profile. This is consistent with the increase of oxidation degree in the regolith. And it is also suggested that the wet/dry climate change during chemical weathering caused Ce alternative change between enrichment and invariance in the upper regolith. Chondrite-normalized REE distribution patterns for samples from dolomites and the lower regolith are characteristic of MREE enrichment and remarkable negative Ce-anomalies patterns (similar to the convex-up REE patterns). The following processes are interpreted for the patterns in this study: (1) the accumulation of MRRE-rich minerals in dolomite dissolution, (2) water-rock interaction in the weathering front, and (3) more leaching MREE from the upper part of the profile. The latter two explanations are considered as the dominant process for the formation of the REE patterns. Samples from the soil horizon exhibit typical REE distribution patterns of the upper crust, i.e., La-N/Yb-N = 10 and Eu/Eu* = 0.65. All data indicate that the leaching process is very important for pedogenesis in this region. The experiments demonstrating that abnormal enrichment of REE at the upper regolith-bedrock interface is caused by a combination of volume change, accumulation of REE-bearing minerals, leaching of REE from the upper regolith, and water-rock interaction during rock-soil alteration processes. Our results support the conclusion that the weathering profile represents a large, continental elemental storage reservoir, whereas REE enrichment occurs under favorable conditions in terms of stable tectonics, low erosion and rapid weathering over sufficiently long time. (C) 2003 Elsevier B.V. All rights reserved

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