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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 unaltered rock is rock that has not experienced physical or chemical erosion [16].?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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Featured articles from other Geoscience Journals
Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
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Your search for risk assessment (Keyword) returned 16 results for the whole karstbase:
Showing 1 to 15 of 16
Risk assessment methodology for karst aquifers .2. Solute-transport modeling, 1997, Field Ms,
Ground-water flow and solute-transport simulation modeling are major components of most exposure and risk assessments of contaminated aquifers. Model simulations provide information on the spatial and temporal distributions of contaminants in subsurface media but are difficult to apply to karst aquifers in which conduit flow is important. Ground-water flow and solute transport in karst conduits typically display rapid-flow velocities, turbulent-flow regimes, concentrated pollutant-mass discharge, and exhibit open-channel or closed-conduit how Conventional groundwater models, dependent on the applicability of Darcy's law, are inappropriate when applied to karst aquifers because of the (1) nonapplicability of Darcian-flow parameters, (2) typically nonlaminar flow regime, and (3) inability to locate the karst conduits through which most flow and contaminant transport occurs. Surface-water flow and solute-transport models conditioned on a set of parameters determined empirically from quantitative ground-water tracing studies may be effectively used to render fate-and-transport values of contaminants in karst conduits. Hydraulic-flow and geometric parameters developed in a companion paper were used in the surface-water model, TOXI5, to simulate hypothetical slug and continuous-source releases of ethylbenzene in a karst conduit. TOXI5 simulation results showed considerable improvement for predicted ethylbenzene-transport rates and concentrations over qualitative tracing and analytical ground-water model results. Ethylbenzene concentrations predicted by TOXI5 simulations were evaluated in exposure and risk assessment models


Risk assessment methodology for karst aquifers .1. Estimating karst conduit-flow parameters, 1997, Field Ms, Nash Sg,
Quantitative ground-water tracing of conduit-dominated karst aquifers allows for reliable and practical interpretation of karst ground-water flow. Insights into the hydraulic geometry of the karst aquifer may be acquired that otherwise could not be obtained by such conventional methods as potentiometric-surface mapping and aquifer testing. Contamination of karst aquifers requires that a comprehensive tracer budget be performed so that karst conduit hydraulic-flow and geometric parameters be obtained. Acquisition of these parameters is necessary for estimating contaminant fate-and-transport. A FORTRAN computer program for estimating total tracer recovery from tracer-breakthrough curves is proposed as a standard method. Estimated hydraulic-flow parameters include mean residence time, mean flow velocity, longitudinal dispersivity, Peclet number, Reynolds number, and Froude number. Estimated geometric parameters include karst conduit sinuous distance, conduit volume, cross-sectional area, diameter, and hydraulic depth. These parameters may be used to (1) develop structural models of the aquifer, (2) improve aquifer resource management, (3) improve ground-water monitoring systems design, (4) improve aquifer remediation, and (5) assess contaminant fate-and-transport. A companion paper demonstrates the use of these hydraulic-flow and geometric parameters in a surface-water model for estimating contaminant fate-and-transport in a karst conduit. Two ground-water tracing studies demonstrate the utility of this program for reliable estimation of necessary karst conduit hydraulic-flow and geometric parameters


Linear and nonlinear input/output models for karstic springflow and flood prediction at different time scales, 1999, Labat D. , Ababou R. , Mangin A. ,
Karstic formations function as three-dimensional (3D) hydrological basins, with both surface and subsurface flows through fissures, natural conduits, underground streams and reservoirs. The main characteristic of karstic formations is their significant 3D physical heterogeneity at all scales, from fine fissuration to large holes and conduits. This leads to dynamic and temporal variability, e.g, highly variable flow rates, due to several concurrent flow regimes with several distinct response times. The temporal hydrologic response of karstic basins is studied here from an input/output, systems analysis viewpoint. The hydraulic behaviour of the basins is approached via the relationship between hydrometeorological inputs and outputs. These processes are represented and modeled as random, self-correlated and cross-correlated, stationary time processes. More precisely, for each site-specific case presented here, the input process is the total rainfall on the basin and the output process is the discharge rate at the outlet of the basin (karstic spring). In the absence of other data, these time processes embody all the available information concerning a given karstic basin. In this paper, we first present a brief discussion of the physical structure of karstic systems. Then, we formulate linear and nonlinear models, i.e. functional relations between rainfall and runoff, and methods for identifying the kernel and coefficients of the functionals (deterministic vs. statistical; error minimisation vs. polynomial projection). These are based mostly on Volterra first order (linear) or second order (nonlinear) convolution. In addition, a new nonlinear threshold model is developed, based on the frequency distribution of interannual mean daily runoff. Finally, the different models and identification methods are applied to two karstic watersheds in the french Pyrenees mountains, using long sequences of rainfall and spring outflow data at two different sampling rates (daily and semi-hourly). The accuracy of nonlinear and linear rainfall-runoff models is tested at three time scales: long interannual scale (20 years of daily data), medium or seasonal scale (3 months of semi-hourly data), and short scale or 'flood scale' (2 days of semi-hourly data). The model predictions are analysed in terms of global statistical accuracy and in terms of accuracy with respect to high flow events (floods)

Working with knowledge at the science/policy interface: a unique example from developing the Tongass Land Management Plan, 2000, Shawiii Charles G. , Everest Fred H. , Swanston Douglas N. ,
An innovative, knowledge-based partnership between research scientists and resource managers in the U.S. Forest Service provided the foundation upon which the Forest Plan was developed that will guide management on the Tongass National Forest for the next 10-15 years. Criteria developed by the scientists to evaluate if management decisions were consistent with the available information base were applied to major components of the emerging final management strategy for the Forest. While the scientists remained value neutral on the contents of the Forest Plan and the management directions provided in it, their evaluation indicated that the decisions it contained for riparian and fish sustainability, wildlife viability, karst and cave protection, slope stability, timber resources, social/economic effects, and monitoring achieved a high degree of consistency with the available scientific information. The Forest Plan, revised to conform with existing scientific knowledge, represents a management strategy designed to sustain the diversity and productivity of the ecosystem while producing goods and services commensurate with the agency’s multiple-use mandate. Execution of this research/management partnership highlighted the role of scientific knowledge in forestry decision-making and provided a new mechanism to input such information into the decision making process. The partnership continues as the scientists are addressing high priority information needs generated by the planning effort in order to have additional information available for plan implementation and revision through adaptive management over the next 3-5 years

Regional risk assessment of karst collapse in Tangshan, China, 2001, Hu , Yeung , Lee , Wang , Xiang ,

Regional risk assessment of karst collapsed in Tangshan, China, 2001, Hu R. L. , Yeung M. R. , Lee C. F. , Wang S. J. , Xiang J. X. ,
This paper discusses the reasons why the number of karst collapses has been increasing in Tangshan, China, since 1978. It gives the main factors that influence the regional risk of karst collapse and the method for assessing it. Using the risk assessment method developed, three zones in downtown Tangshan, with different risk levels, were delineated. Based on the risk assessment results, some recommendations are given on the treatment of karst collapse and related urban engineering issues

Application of matrix analysis in delineating sinkhole risk areas along highway (I-70 near Frederick, Maryland), 2003, Zhou W. F. , Beck B. F. , Adams A. L. ,
Sinkhole collapse in the area of Maryland Interstate 70 (I-70) and nearby roadways south of Frederick, Maryland, has been posing a threat to the safety of the highway operation as well as other structures. The occurrence of sinkholes is associated with intensive land development. However, the geological conditions that have been developing over the past 200 million years in the Frederick Valley control the locations of the sinkholes. Within an area of approximately 8 km(2), 138 sinkholes are recorded and their spatial distribution is irregular, but clustered. The clustering indicates the existence of an interaction between the sinkholes. The point pattern of sinkholes is considered to be a sample of a Gibbsian point process from which the hard-core Strauss Model is developed. The radius of influence is calculated for the recorded sinkholes which are most likely to occur within 30 m of an existing sinkhole. The stochastic analysis of the existing sinkholes is biased toward the areas with intensive land use. This bias is adjusted by considering (1) topography, (2) proximity to topographic depressions, (3) interpreted rock formation, (4) soil type, (5) geophysical anomalies, (6) proximity to geologic structures, and (7) thickness of overburden. Based on the properties of each factor, a scoring system is developed and the average relative risk score for individual 30-m segments of the study area is calculated. The areas designated by higher risk levels would have greater risk of a sinkhole collapse than the areas designated by lower risk levels. This risk assessment approach can be updated as more information becomes available

Roadway construction in karst areas: management of stormwater runoff and sinkhole risk assessment, 2005, Zhou Wanfang, Beck Barry F. ,

Sinkholes and the Engineering and Environmental Impacts of Karst, 2005, Beck B. F.

Conference Proceedings

Sinkholes and the Engineering and Environmental Impacts of Karst Contains over 70 papers addressing karst topography which impacts water resources, waste disposal, foundation stability, and a multitude of other geotechnical and environmental issues. These papers were presented at the 10th Multidisciplinary Conference held September 24-28, 2005 in San Antonio, Texas and Sponsored by the Geo-Institute of ASCE, P. E. LaMoreaux & Associates, Inc. and Edwards Aquifer Authority. The goal of this conference was to share knowledge and experience among disciplines by emphasizing practical applications and case studies. This proceedings will benefit environmental and geotechnical engineers, and others involved in water resources, water disposal, and foundation stability issues.


Application of Geophysical Logging Techniques for Multi-Channel Well Design and Installation in a Karst Aquifer (by Frank Bogle, ...)

Case Studies of Massive Flow Conduits in Karst Limestone (by Jim L. Lolcama)

A Case Study of the Samanalawewa Reservoir on the Walawe River in an Area of Karst in Sri Lanka (by K. Laksiri, ...)

Characterization and Water Balance of Internal Drainage Sinkholes (by Nico M. Hauwert, ...)

Characterization of Desert Karst Terrain in Kuwait and the Eastern Coastline of the Arabian Penninsula (by Waleed Abdullah, ...)

Characterization of a Sinkhole Prone Retention Pond Using Multiple Geophysical Surveys and Closely Spaced Borings (by Nick Hudyma, ...)

Combining Surface and Downhole Geophysical Methods to Identify Karst Conditions in North-Central Iowa (by J. E. Wedekind, ...)

Complexities of Flood Mapping in a Sinkhole Area (by C. Warren Campbell, P.E.)

Conceptualization and Simulation of the Edwards Aquifer, San Antonio Region, Texas (by R. J. Lindgren, ...)

Database Development and GIS Modeling to Develop a Karst Vulnerability Rating for I-66, Somerset to London, KY (by Michael A. Krokonko, ...)

Design and Construction of the Foundations for the Watauga Raw Water Intake Facility in Karstic Limestone near the City of Johnson City, TN (by Tony D. Canale, P.E., ...)

Detection of Three-Dimensional Voids in Karstic Ground (by Derek V. Morris, P.E., ...)

Development and Evolution of Epikarst in Mid-Continent US Carbonates (by Tony L. Cooley, P.E.)

Dye Tracing Sewage Lagoon Discharge in a Sandstone Karst, Askov, Minnesota (by Emmit Calvin Alexander, Jr., ...)

The Effectiveness of GPR in Sinkhole Investigations (by E. D. Zisman, P.E., ...)

Effects of Anthropogenic Modification of Karst Soil Texture on the Water Balance of ?Alta Murgia? (Apulia, Italy) (by F. Canora, ...)

Environmental Isotope Study on Recharge and Groundwater Residence Time in a covered Ordovician Carbonate Rock (by Zhiyuan Ma, ...)

Error and Technique in Fluorescent dye Tracing (by Chris Smart)

Essential Elements of Estimating Engineering Properties of Karst for Foundation Design (by Ramanuja Chari Kannan, P.E., Fellow, ASCE)

Estimating Grout Quantities for Residential Repairs in Central Florida Karst (by Larry D. Madrid, P.E., ...)

Evaluation of Groundwater Residence Time in a Karstic Aquifer Using Environmental Tracers: Roswell Artesian Basin, New Mexico (by Lewis Land)

Experience of Regional Karst Hazard and Risk Assessment in Russia (by A. L. Ragozin, ...)

Experimental Study of Physical Models for Sinkhole Collapses in Wuhan, China (by Mingtang Lei, ...)

Fractal Scaling of Secondary Porosity in Karstic Exposures of the Edwards Aquifer (by Robert E. Mace, ...)

The Geological Characteristics of Buried Karst and Its Impact on Foundations in Hong Kong, China (by Steve H. M. Chan, ...)

Geophysical Identification of Evaporite Dissolution Structures Beneath a Highway Alignment (by M. L. Rucker, ...)

Geotechnical Analysis in Karst: The Interaction between Engineers and Hydrogeologists (by R. C. Bachus, P.E.)

The Gray Fossil Site: A Spectacular Example in Tennessee of Ancient Regolith Occurrences in Carbonate Terranes, Valley and Ridge Subpovince, South Appalachians U.S.A. (by G. Michael Clark, ...)

Ground-Water Basin Catchment Delineation by Bye Tracing, Water Table Mapping, Cave Mapping, and Geophysical Techniques: Bowling Green Kentucky (by Nicholas C. Crawford)

Groundwater Flow in the Edwards Aquifer: Comparison of Groundwater Modeling and Dye Trace Results (by Brian A. Smith, ...)

Grouting Program to Stop Water Flow through Karstic Limestone: A Major Case History (by D. M. Maciolek)

Highway Widening in Karst (by M. Zia Islam, P.E., ...)

How Karst Features Affect Recharge? Implication for Estimating Recharge to the Edwards Aquifer (by Yun Huang, ...)

Hydrogeologic Investigation of Leakage through Sinkholes in the Bed of Lake Seminole to Springs Located Downstream from Jim Woodruff Dam (by Nicholas C. Crawford, ...)

The Hydrologic Function of the soil and Bedrock System at Upland Sinkholes in the Edwards Aquifer Recharge Zone of South-Central Texas (by A. L. Lindley)

An Integrated Geophysical Approach for a Karst Characterization of the Marshall Space Flight Center (by Lynn Yuhr, ...)

Integrated Geophysical Surveys Applied to Karstic Studies Over Transmission Lines in San Antonio, Texas (by Mustafa Saribudak, ...)

Judge Dillon and Karst: Limitations on Local Regulation of Karst Hazards (by Jesse J. Richardson, Jr.)

Karst Groundwater Resource and Advantages of its Utilization in the Shaanbei Energy Base in Shaanxi Province, China (by Yaoguo Wu, ...)

Karst Hydrogeology and the Nature of Reality Revisited: Philosophical Musings of a Less Frustrated Curmudgeon (by Emmit Calvin Alexander, Jr.)

Karst in Appalachia ? A Tangled Zone: Projects with Cave-Sized Voids and Sinkholes (by Clay Griffin, ...)

Karstic Features of Gachsaran Evaporites in the Region of Ramhormoz, Khuzestan Province, in Southwest Iran (by Arash Barjasteh)

Large Perennial Springs of Kentucky: Their Identification, Base Flow, Catchment, and Classification (by Joseph A. Ray, ...)

Large Plot Tracing of Subsurface Flow in the Edwards Aquifer Epikarst (by P. I. Taucer, ...)
Lithology as a Predictive Tool of Conduit Morphology and Hydrology in Environmental Impact Assessments (by George Veni)

Metadata Development for a Multi-State Karst Feature Database (by Yongli Gao, ...)

Micropiling in Karstic Rock: New CMFF Foundation Solution Applied at the Sanita Factory (by Marc Ballouz)

Modeling Barton Springs Segment of the Edwards Aquifer Using MODFLOW-DCM (by Alexander Y. Sun, ...)

Multi-Level Monitoring Well Completion Technologies and Their Applicability in Karst Dolomite (by Todd Kafka, ...)

National-Scale Risk Assessment of sinkhole Hazard in China (by Xiaozhen Jiang, ...)

New Applications of Differential Electrical Resistivity Tomography and Time Domain Reflectometry to Modeling Infiltration and Soil Moisture in Agricultural Sinkholes (by B. F. Schwartz, ...)

Non-Regulatory Approaches to Development on Karst (by Jesse J. Richardson, Jr., ...)

PA State Route 33 Over Bushkill Creek: Structure Failure and Replacement in an Active Sinkhole Environment (by Kerry W. Petrasic, P.E.)

Quantifying Recharge via Fractures in an Ashe Juniper Dominated Karst Landscape (by Lucas Gregory, ...)

Quantitative Groundwater Tracing and Effective Numerical Modeling in Karst: An Example from the Woodville Karst Plain of North Florida (by Todd R. Kincaid, ...)

Radial Groundwater Flow at Landfills in Karst (by J. E. Smith)

Residual Potential Mapping of Contaminant Transport Pathways in Karst Formations of Southern Texas (by D. Glaser, ...)

Resolving Sinkhole Issues: A State Government Perspective (by Sharon A. Hill)

Shallow Groundwater and DNAPL Movement within Slightly Dipping Limestone, Southwestern Kentucky (by Ralph O. Ewers, ...)

Sinkhole Case Study ? Is it or Isn?t it a Sinkhole? (by E. D. Zisman, P.E.)

Sinkhole Occurrence and Changes in Stream Morphology: An Example from the Lehigh Valley Pennsylvania (by William E. Kochanov)

Site Characterization and Geotechnical Roadway Design over Karst: Interstate 70, Frederick County, Maryland (by Walter G. Kutschke, P.E., ...)

Soil Stabilization of the Valley Creek Trunk Sewer Relief Tunnel (by Jeffrey J. Bean, P.E., ...)

Some New Approaches to Assessment of Collapse Risks in Covered Karsts (by Vladimir Tolmachev, ...)

Spectral Deconvolution and Quantification of Natural Organic Material and Fluorescent Tracer Dyes (by Scott C. Alexander)

Springshed Mapping in Support of Watershed Management (by Jeffrey A. Green, ...)

Sustainable Utilization of Karst Groundwater in Feicheng Basin, Shandong Province, China (by Yunfeng Li, ...)

Transport of Colloidal and Solute Tracers in Three Different Types of Alpine Karst Aquifers ? Examples from Southern Germany and Slovenia (by N. Göppert, ...)

Use of the Cone Penetration Test for Geotechnical Site Characterization in Clay-Mantled Karst (by T. C. Siegel, ...)

The Utility of Synthetic Aperture Radar (SAR) Interferometry in Monitoring Sinkhole Subsidence: Subsidence of the Devil?s Throat Sinkhole Area (Nevada, USA) (by Rana A. Al-Fares)

Void Evolution in Soluble Rocks Beneath Dams Under Limited Flow Condition (by Emmanuel S. Pepprah, ...)

The protection of karst waters. A comprehensive Slovene Approach to vulnerability and contamination risk mapping, 2007, Nataš, A Ravbar
A general approach for karst water vulnerability and contamination risk assessment has been proposed, taking into account the special characteristics of Slovene karst landscapes, suiting Slovene environmental legislation and enabling comparison across European countries. The so-called Slovene Approach has been developed on the basis of work accomplished by the European COST Action 620. It incorporates the strongly modified COP method for intrinsic vulnerability assessment by integrating temporal hydrological variability, offering a new possibility to combine surface and groundwater protection, as well as by adapting it to source vulnerability mapping. The methodology provides also comprehensive risk analyses based on the intrinsic vulnerability, hazard and (re)source importance assessments. The proposed Slovene Approach has been first applied to the Podstenjšek water source catchment. Different other methods have been applied (EPIK, PI, COP, Simplified method) and compared. For the catchment area delineation, application of different vulnerability and risk methods a holistic research of the test site has been done by means of tracer tests, detail structural-lithological and geomorphological mapping, electrical resistivity imaging, as well as detail hazard mapping. Continuous monitoring of the springs? physico-chemical characteristics has been performed for the hydrograph analyses, water balance calculation and aquifer behaviour comprehension. The resulting Slovene Approach intrinsic vulnerability, hazard and risk maps are justified and validation with tracer tests has proved the method to give plausible results. The resulting maps provide improved source protection zones determination and identification of land mismanagement, as well as reorganisation and better practices for future planning.


On the basis of work accomplished by the European COST Action 620, a comprehensive approach to groundwater vulnerability and contamination risk assessment is proposed, taking into account the special characteristics of Slovene karst aquifer systems. The Slovene Approach is consistent with national environmental legislation and enables comparison across European countries. The method integrates temporal hydrological variability in the concept of groundwater vulnerability and offers a new possibility to combine surface and groundwater source and resource protection, which required the development of a new K factor (karst groundwater flow within the saturated zone). The risk analysis considers intrinsic vulnerability, contamination hazards and the importance of the source or resource. It has been first applied to the Podstenjšek springs catchment in southwestern Slovenia and validated by means of two multi-tracer tests with a total of six injection points. The resulting vulnerability, hazard and risk maps are plausible, and the validation confirmed the vulnerability assessment at the representative sites that were selected for tracer injection. The maps provide improved source protection zones and make it possible to identify land mismanagement and to propose better practices for future planning.

Effectiveness and adequacy of well sampling using baited traps for monitoring the distribution and abundance of an aquatic subterranean isopod, 2009, 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.

KARST HAZARDS, 2013, Andreychouk Viacheslav, Tyc Andrzej

Karst hazards are an important example of natural hazards. They occur in areas with soluble rocks (carbonates, mostly limestone, dolomite, and chalk; sulfates, mostly gypsum and anhydrite; chlorides, mostly rock salt and potassium salt; and some silicates, quartzite and amorphous siliceous sediments) and efficient underground drainage. Karst is one of the environments in the world most vulnerable to natural and human-induced hazards. Karst hazards involve fast-acting processes, both on the surface and underground (e.g., collapse, subsidence, slope movements, and floods) and their effects (e.g., sinkholes, degraded aquifers, and land surface). They frequently cause serious damage in karst areas around the world, particularly in areas of intense human activity. Karst threat is the potential hazard to the life, health, or welfare of people and infrastructure, arising from the particular geological structure and function of karst terrains. The presence of underground cavities in the karst massif masks the threat from the hazards of collapse. This means that in some instances, the potential threats from karst, which are inherent features of the karst environment, become hazards. They range in category from potential to real. The term (karst hazards) is related to two other terms, used mostly in applied geosciences, particularly engineering geology – risk assessment and mitigation. Risk is the probability of an occurrence, and the consequential damages are defined as hazards. Risk assessment is the determination of quantitative or qualitative value of risk related to a concrete situation and a recognized hazard. Quantitative risk assessment requires calculations of two components: the magnitude of the potential loss and the probability that the loss will occur. Risk assessment is a step in a risk management. Mitigation may be defined as the reduction of risk to life and the environment by reducing the severity of collapse or subsidence, building subsidence-resistant constructions, restricting land use, etc.

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