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Speleology in Kazakhstan

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

New publications on hypogene speleogenesis

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

The deepest terrestrial animal

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

Caves - landscapes without light

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

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That pressure is the force exerted across a real or imaginary surface divided by the area of that surface.?

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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 optimization (Keyword) returned 8 results for the whole karstbase:
The cricket fauna of Chiapanecan caves (Mexico): systematics, phylogeny and the evolution of troglobitic life (Orthoptera, Grylloidea, Phalangopsidae, Luzarinae), 1993, Desuttergrandcolas Laure
The present study deals with the cavernicolous Grylloidea of Chiapas. It details the composition of this fauna, which belongs exclusively to the Phalangopsid group Amphiacustae, and considers its troglobitic evolution in the methodological framework of Comparative Biology. This method consists in analysing the evolution of biological features in reference to phylogeny, using character state optimization. The material studied comes mostly from Italian biospeological expeditions, but also from the authors work in Mexico, from North American biospeological expeditions achieved in Central America and the West Indies, and from the collections of the Academy of Natural Sciences of Philadelphia, the Museum National d'Histoire naturelle de Paris and the University of Michigan Museum of Zoology. I first present a systematic and phylogenetic analysis of Amphiacustae. Six new genera are defined and the genus Amphiacusta Saussure, 1874 is clearly delimited; twenty-three of the twenty six species considered in the paper are new and described. A key for genera and species groups is given. Phylogenetic relationships among genera are established using cladistics (implicit enumeration of Hennig 86 program). The evolution of troglobitic Amphiacustae is then analyzed. Available data on the biology of Amphiacust genera are presented and compared with what is known on other Phalangopsidae. Three biological attributes are moreover defined (troglobitic versus non troglobitic; cavernicolous versus non cavernicolous; leaf litter foraging versus leaf litter not foraging). The mapping of the attributes upon our cladogram has shown that Amphiacustae evolved twice toward cave life and that their ancestral habitat could be characterized by cavernicolous habits and leaf litter foraging. The results are discussed in reference to theories on troglobitic taxa evolution, and to the exaptation concept of Gould & Vrba (1982). This leads to three main conclusions: 1/ Amphiacust adaptation to caves could be the result of a tentative to exploit karstic resources in Central America; 2/ An epigean dispersion by cave living species can be hypothesized; 3/ For Grylloidea, having cavernicolous habits at ground level appears to be exaptative to troglobitic life.

Spatialized morphological analysis: A method of detecting faults, a necessity for hydrodynamic and karstologic studies of cracked aquifers. Examples of the chalky aquifers of Northern France, 1999, Bonnet T, Colbeaux Jp,
Spatialized Morphological Analysis is a new method of detecting faults which uses the morphometric relief data (slope, aspect, elevation) taken from a precise Digital Elevation Model by a computer program. This program, taking the principles of the evolution of relief into account (rock type, climate, chronology), allows the statistical identification of morphometric standards for each type of morphology and the extraction of anomalies to these standards. Some of these anomalies, after a processing of spatial classification, are considered as tectonic tracks. The actual existence of faults, corresponding with anomalies, is verified by classical methods of structural geology. By a better localisation and geometrical definition of faults, this method can allow the optimization of hydrodynamical studies of cracked aquifers, and in case of calcareous ones, a spatial approach to karstification. This method is applied to the north of France chalky aquifer, where, associated with detailed hydrogeological records, it allowed the identification of rapid transfers of groundwater at the level of faults. Even so, exokarstic phenomena are uncommon in this area. Some chemical and textural particularities of Quaternary chalk cover may be the cause of rainwater inhibition, and it is possible that the karstic responses observed are due to considerable mechanical dissolution in the saturated area where tectonic activity (neotectonic faults have been observed) creates environments of preferential flow. (C) Elsevier, Paris

Simulated effect of vadose infiltration on water levels in the Northern Guam Lens Aquifer, 2000, Contractor Dn, Jenson Jw,
Regional-scale hydrology of the fresh water lens in the Northern Guam Lens Aquifer has been simulated in the past using a finite element, sharp interface computer model, SWIG2D. Systematic differences exist between observed and computed water levels. Computed seasonal peak water levels are higher, and the computed seasonal lows are lower than the respective observed levels. It is hypothesized that vadose storage must store a substantial amount of water during the wet season and release it gradually into the lens during the dry season. Flow through the vadose zone was simulated with a one-dimensional finite element, unsaturated flow program UNSATID, in which the van Genuchten model is used to characterize unsaturated diffuse flow through the matrix of the vadose zone. An additional parameter (SINK) was added to the van Genuchten set to account for rapid infiltration down open pathways (fractures) associated with the closed depressions of the karst terrain. A global-optimization technique (Shuffled Complex Evolution or SCE-UA Method) was used to obtain the parameters that minimized the difference between simulated and observed water levels. Simulations incorporating the van Genuchten model were accomplished by combining the two programs, UNSATID and SWIG2D, into a single program. The sum-of-squared-errors (SSE) between computed and observed water levels in four observation wells was minimized using SCE-UA, reducing the arithmetically averaged SSE of the four wells by 30% compared with the SSE obtained when the vadose zone was not modeled. These results suggest that vadose storage is significant. On the other hand, the fact that the best fit obtained with an optimum parameter set was able to reduce the SSE by no more than 30% suggests that additional phenomena have yet to be accounted for to mon fully explain differences between simulated and observed well water levels. (C) 2000 Elsevier Science B.V. All rights reserved

Comparison of immunofluorescence assay and immunomagnetic electrochemiluminescence in detection of Cryptosporidium parvum oocysts in karst water samples, 2003, Kuczynska E. , Boyer D. G. , Shelton D. R. ,
Immunofluorescence assay (IFA) and immunomagneticelectrochemiluminescence (IM-ECL) were used for comparison of the percent recovery of Cryptosporidium parvum in environmental water samples obtained from a spring draining a karst basin. The monoclonal antibodies to C. parvum, isotype IgG3 were used for optimization of the IM-ECL protocol. The combination of biotinylated and TAG-labeled anti-C. parvum antibodies with the streptavidin beads gave a linear regression slope for log ECL vs. log fresh oocysts of 0.79 (from 5 to 5000 oocysts), which indicates a constant ECL signal per oocyst. Standard curves gave a dynamic range of 5 to 5000 oocysts/ml (fresh) and 10 to 100,000 cells/ml (4-month-old oocysts) with the maximum limit of linear detection higher than 100,000. The linear slope of 4-month-old oocysts decreased to 0.62, which indicates that ECL signal is a function of oocyst age. The experiment associated with bead storage time shows that even after 4 months of storage of the biotinylated antibodies, the complex retains the ability for binding the oocysts and generating the ECL signal. Based on the IFA results in the experiment evaluating different protocols for oocysts recovery from karst water samples, the most efficient protocol involved dispersion, followed by flotation and immunomagnetic separation (IMS) (24% recovery). The ECL results obtained in that experiment were very similar to the results obtained in the IFA method, which indicates that the IM-ECL method is accurate. Results of the IFA in the study of the prevalence of C. parvum in the groundwater showed that oocysts were present in 78% of 1 L water samples with average number of oocysts of 6.4 5.5 and ranged from 0 (13 samples) to 23.3 (2 samples). The ECL signal generated from these water samples ranged from 3771 to 622 (average 1620 465). However, the background value estimated in groundwater samples with low number of oocysts detected by IFA was highly variable and elevated (from 3702 to 272, average 1503 475). The background value as a result of nonspecific binding to beads by unidentified organic components in the water can inhibit or even completely mask the signal generated by oocysts. Our investigations showed that the IM-ECL method appears to be promising for the qualitative and quantitative detection of C parvum from the environmental water; however, the method requires further development to improve sensitivity and account for background signals. Published by Elsevier Science B.V

Linear model describing three components of flow in karst aquifers using O-18 data, 2004, Long A. J. , Putnam L. D. ,
The stable isotope of oxygen, 180, is used as a naturally occurring ground-water tracer. Time-series data for 5 180 are analyzed to model the distinct responses and relative proportions of the conduit, intermediate, and diffuse flow components in karst aquifers. This analysis also describes mathematically the dynamics of the transient fluid interchange between conduits and diffusive networks. Conduit and intermediate flow are described by linear-systems methods, whereas diffuse flow is described by mass-balance methods. An automated optimization process estimates parameters of lognormal, Pearson type III, and gamma distributions, which are used as transfer functions in linear-systems analysis. Diffuse flow and mixing parameters also are estimated by these optimization methods. Results indicate the relative proximity of a well to a main conduit flowpath and can help to predict the movement and residence times of potential contaminants. The three-component linear model is applied to five wells, which respond to changes in the isotopic composition of point recharge water from a sinking stream in the Madison aquifer in the Black Hills of South Dakota. Flow velocities as much as 540 m/d and system memories of as much as 71 years are estimated by this method. Also, the mean, median, and standard deviation of traveltimes; time to peak response; and the relative fraction of flow for each of the three components are determined for these wells. This analysis infers that flow may branch apart and rejoin as a result of an anastomotic (or channeled) karst network. Published by Elsevier B.V

Water quality modelling of Jadro spring, 2004, Margeta J. , Fistanic I. ,
Management of water quality in karst is a specific problem. Water generally moves very fast by infiltration processes but far more by concentrated flows through fissures and openings in karst. This enables the entire surface pollution to be transferred fast and without filtration into groundwater springs. A typical example is the Jadro spring. Changes in water quality at the spring are sudden, but short. Turbidity as a major water quality problem for the karst springs regularly exceeds allowable standards. Former practice in problem solving has been reduced to intensive water disinfection in periods of great turbidity without analyses of disinfection by-products risks for water users. The main prerequisite for water quality control and an optimization of water disinfection is the knowledge of raw water quality and nature of occurrence. The analysis of monitoring data and their functional relationship with hydrological parameters enables establishment of a stochastic model that will help obtain better information on turbidity in different periods of the year. Using the model a great number of average monthly and extreme daily values are generated. By statistical analyses of these data possibility of occurrence of high turbidity in certain months is obtained. This information can be used for designing expert system for water quality management of karst springs. Thus, the time series model becomes a valuable tool in management of drinking water quality of the Jadro spring

Seawater intrusion in complex geological environments, 2005, Abarca Cameo, Elena

Modelling seawater intrusion (SWI) has evolved from a tool for understanding to a water management need. Yet, it remains a challenge. Difficulties arise from the assessment of dispersion coefficients and the complexity of natural systems that results in complicated aquifer geometries and heterogeneity in the hydraulic parameters. Addressing such difficulties is the objective of this thesis. Specifically, factors that may affect the flow and transport in coastal aquifers and produce heterogeneous salinity distributions are studied.

First, a new paradigm for seawater intrusion is proposed since the current paradigm (the Henry problem) fails to properly reproduce observed SWI wedges. Mixing is represented by means of a velocity dependent dispersion tensor in the new proposed problem. Thereby, we denote it as "dispersive Henry problem". SWI is characterized in terms of the wedge penetration, width of the mixing zone and influx of seawater. We find that the width of the mixing zone depends basically on dispersion, with longitudinal and transverse dispersion controlling different parts of the mixing zone but displaying similar overall effects. The wedge penetration is mainly controlled by the horizontal permeability and by the geometric mean of the dispersivities. Transverse dispersivity and the geometric mean of the hydraulic conductivity are the leading parameters controlling the amount of salt that enters the aquifer.

Second, the effect of heterogeneity was studied by incorporating heterogeneity in the hydraulic permeability into the modified Henry problem. Results show that heterogeneity causes the toe to recede while increases both the width and slope of the mixing zone. The shape of the interface and the saltwater flux depends on the distribution of the permeability in each realization. However, the toe penetration and the width of the mixing zone do not show large fluctuations. Both variables are satisfactorily reproduced, in cases of moderate heterogeneity, by homogeneous media with equivalent permeability and either local or effective dispersivities.

Third, the effect of aquifer geometry in horizontally large confined aquifers was analyzed. Lateral slope turned out to be a critical factor. Lateral slopes in the seaside boundary of more than 3% cause the development of horizontal convection cells. The deepest zones act as preferential zones for seawater to enter the aquifer and preferential discharging zones are developed in the upwards lateral margins. A dimensionless number, Nby, has been defined to estimate the relative importance of this effect.

All these factors can be determinant to explain the evolution of salinity in aquifers such as the Main aquifer of the Llobregat delta. Finally, a management model of this aquifer is developed to optimally design corrective measures to restore the water quality of the aquifer. The application of two different optimization methodologies, a linear and a non-linear optimization method, allowed (1) to quantify the hydraulic efficiency of two potential corrective measures: two recharge ponds and a seawater intrusion barrier; (2) to determine the water necessary to be injected in each of these measures to restore the water quality of the aquifer while minimizing changes in the pumping regime and (3) to assess the sustainable pumping regime (with and without the implementation of additional measures) once the water quality has been restored. Shadow prices obtained from linear programming become a valuable tool to quantify the hydraulic efficiency of potential corrective measures to restore water quality in the aquifer

Optimization of nutrient medium for submerged cultivation of Ganoderma lucidum (Curt.: Fr.) P. Karst, 2006, Avtonomova A, Krasnopol T, Maksimov V,

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