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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 fissure is an open joint or crack in rocks [16].?

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

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
See all featured articles
Featured articles from other Geoscience Journals
Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
See all featured articles from other geoscience journals

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Your search for dna (Keyword) returned 48 results for the whole karstbase:
Showing 16 to 30 of 48
Filamentous 'Epsilonproteobacteria' dominate microbial mats from sulfidic cave springs, 2003, Engel As, Lee N, Porter Ml, Stern La, Bennett Pc, Wagner M,
Hydrogen sulfide-rich groundwater discharges from springs into Lower Kane Cave, Wyoming, where microbial mats dominated by filamentous morphotypes are found. The full-cycle rRNA approach, including 16S rRNA gene retrieval and fluorescence in situ hybridization (FISH), was used to identify these filaments. The majority of the obtained 16S rRNA gene clones from the mats were affiliated with the 'Epsilonproteobacteria' and formed two distinct clusters, designated LKC group I and LKC group II, within this class. Group I was closely related to uncultured environmental clones from petroleum-contaminated groundwater, sulfidic springs, and sulfidic caves (97 to 99% sequence similarity), while group II formed a novel clade moderately related to deep-sea hydrothermal vent symbionts (90 to 94% sequence similarity). FISH with newly designed probes for both groups specifically stained filamentous bacteria within the mats. FISH-based quantification of the two filament groups in six different microbial mat samples from Lower Kane Cave showed that LKC group II dominated five of the six mat communities. This study further expands our perceptions of the diversity and geographic distribution of 'Epsilonproteobacteria' in extreme environments and demonstrates their biogeochemical importance in subterranean ecosystems

Dental morphology of the Dawenkou Neolithic population in North China: implications for the origin and distribution of Sinodonty, 2003, Manabe Y. , Oyamada J. , Kitagawa Y. , Rokutanda A. , Kato K. , Matsushita T. ,
We compare the incidence of 25 nonmetric dental traits of the people of the Neolithic Dawenkou culture (6300-4500 BP) sites in Shandong Province, North China with those of other East Asian populations. The Dawenkou teeth had an overwhelmingly greater resemblance to the Sinodont pattern typical of Northeast Asia than to the Sundadont pattern typical of Southeast Asia. Multidimensional scaling using Smith's mean measure of divergence (MMD) statistic place the Dawenkou sample near the Amur and the North China-Mongolia populations in the area of the plot indicating typical Sinodonty. The existence of the Sinodont population in Neolithic North China suggests a possible continuity of Sinodonty from the Upper Cave population at Zhoukoudian (about 34,000-10,000 BP) to the modern North Chinese. The presence of Sinodonty in Shandong Province shows that the Japan Sea and East China Sea were strong barriers to gene flow for at least 3000 years, because at this time the Jomonese of Japan were fully Sundadont. In addition, we suggest that the descendants of the Dawenkou population cannot be excluded as one of the source populations that contributed to sinodontification in Japan. (C) 2003 Elsevier Ltd. All rights reserved

Der neue Stammbaum der alpinen Hhlenbren., 2004, Rabeder G. , Hofreiter M.
In the Upper Pleistocene the Alps were inhabited by at least three taxa of cave bear (group) which differ in their mitochondrial DNA as well as in metrical and morphological criteria. The possibilities of distinguishing these evolutionary lineages in the fossil record are described and discussed. Two high Alpine dwarf forms are described as possible subspecies of U. spelaeus (U. s.? ladinicus and U. s.? eremus), the third taxon is separated as an independent species (U. ingressus). By means of numerous diagrams an attempt is made to find metrical and morphological differences in the teeth and limb bones in order to distinguish the three Alpine taxa. A new phylogenetic tree is drawn. [Hhlenbren-Forschung in Europa, DNA-Untersuchungen]

Evidence for reproductive isolation between cave bear populations, 2004, Hofreiter M. , Rabeder G. , Jaenickedespres V. , Withalm G. , Nagel D. , Paunovic M. , Jambresic G. , Paabo S. ,
The European cave bear (Ursus spelaeus), which became extinct around 15,000 years ago, had several morphologically different forms. Most conspicuous of these were small Alpine cave bears found at elevations of 1,600 to 2,800 m [1-3]. Whereas some paleontologists have considered these bears a distinct form [4, 5], or even a distinct species [6], others have disputed this [7-9]. By a combination of morphological and genetic methods, we have analyzed a population of small cave bears from Ramesch Cave (2,000 m altitude) and one of larger cave bears from Gamssulzen Cave (1,300 m), situated approximately 10 km apart in the Austrian Alps (Figure 1A). We find no evidence of mitochondrial gene flow between these caves during the 15,000 years when they were both occupied by cave bears, although mitochondrial DNA sequences identical to those from Gamssulzen Cave could be recovered from a site located about 200 km to the south in Croatia. We also find no evidence that the morphology of the bears in the two caves changed to become more similar over time. We suggest that the two cave bear forms may have represented two reproductively isolated subspecies or species

Bacterial diversity and ecosystem function of filamentous microbial mats from aphotic (cave) sulfidic springs dominated by chemolithoautotrophic 'Epsilonproteobacteria', 2004, Engel As, Porter Ml, Stern La, Quinlan S, Bennett Pc,
Filamentous microbial mats from three aphotic sulfidic springs in Lower Kane Cave. Wyoming. were assessed with regard to bacterial diversity, community structure, and ecosystem function using a 16S rDNA-based phylogenetic approach combined with elemental content and stable carbon isotope ratio analyses. The most prevalent mat morphotype consisted of while filament bundles, with low C:N ratios (3.5-5.4) and high sulfur content (16.1-51.2%). White filament bundles and two other mat morphotypes organic carbon isotope values (mean delta(13)C = -34.7parts per thousand: 1sigma = 3.6) consistent with chemolithoautotrophic carbon fixation from a dissolved inorganic carbon reservoir (cave water, mean delta(13)C = -7.47parts per thousand for two springs, n = 8). Bacterial diversity was as low overall in the clone libraries, and the most abundant taxonomic group was affiliated with the 'Epsilonproteobacteria' (68%) with other bacterial sequences affiliated with Gammaproteobacteria (12.2%), Betaproteobacteria (11.7%), Deltaproteobacteria (0.8%), and the Acidobacterium (5.6%) and Bacteriodetes/Chlorobi (1.7%) divisions. Six distinct epsilonproteobacterial taxonomic groups were identified from the microbial mats. Epsilonproteobacterial and bacterial group abundances and community structure shifted front the spring orifices downstream. corresponding to changes in dissolved sulfide and oxygen concentrations and metabolic requirements of certain bacterial groups. Most of the clone sequences for epsilonproteobacterial groups were retrieved from areas with high sulfide and low oxygen concentrations, whereas Thiothrix spp. and Thiobacillus spp. had higher retrieved clone abundances where conditions of low sulfide and high oxygen concentrations were measured. Genetic and metabolic diversity among the 'Epsilonproteobacteria' maximizes overall cave ecosystem function, and these organisms play a significant role in providing chemolithoautotrophic energy to the otherwise nutrient-poor cave habitat. Our results demonstrate that sulfur cycling supports subsurface ecosystem through chemolithoautotrophy and expand the evolutionary and ecological views of 'Epsilonproteobacteria' in terrestrial habitats. (C) 2004 Federation of European Microbiological Societies. Published by Elsevier BY. All rights reserved

Der neue Stammbaum der alpinen Hhlenbren, 2004, Rabeder G. , Hofreiter M.
In the Upper Pleistocene the Alps were inhabited by at least three taxa of cave bear (group) which differ in their mitochondrial DNA as well as in metrical and morphological criteria. The possibilities of distinguishing these evolutionary lineages in the fossil record are described and discussed. Two high Alpine dwarf forms are described as possible subspecies of U. spelaeus (U. s.? ladinicus and U. s.? eremus), the third taxon is separated as an independent species (U. ingressus). By means of numerous diagrams an attempt is made to find metrical and morphological differences in the teeth and limb bones in order to distinguish the three Alpine taxa. A new phylogenetic tree is drawn.

The distribution and life history of Arrhopalites caecus (Tullberg): Order: Collembola, in Wind Cave, South Dakota, USA., 2005, Moore J. C. , Saunders P. , Selby G. , Horton H. , Chelius M. K. , Chapman A. , Horrocks R. D.
Individuals of the collembolan species Arrhopalites caecus (Tullberg) were collected from drip pools within Wind Cave, South Dakota, at Methodist Church adjacent to the Natural Entrance Tour Route and Room Draculum near survey marker NP-39. Specimens were identified as A. caecus using direct interference and scanning electron microscopy. Molecular analysis of the D2 region of 28S rDNA was performed and the sequences were deposited in Genbank (accession number AY239037). We determined that our population of A. caecus reproduced parthenogenetically by successively isolating and rearing eggs through the F4 generation on 9:5 plaster:charcoal media maintained at 21C, and by the absence of males. Molecular analysis of 16S rDNA for bacterium within our specimens failed to detect the ?-pro-teobacterium (Rickettseales) Wolbachia. Generation times, fecundity, and molt frequency were consistent with other reports for Collembola.

Bacterial dynamics in spring water of alpine karst aquifers indicates the presence of stable autochthonous microbial endokarst communities, 2005, Farnleitner Ah, Wilhartitz I, Ryzinska G, Kirschner Akt, Stadler H, Burtscher Mm, Hornek R, Szewzyk U, Herndl G, Mach Rl,
Spring water of two alpine karst aquifers differing in hydrogeology but of nearby catchments were investigated for their bacterial population dynamics. Dolomite karst aquifer spring 1 (DKAS 1) represents a dolomitic-limestone karst aquifer spring showing high average water residence time and relative constant flow. Limestone karst aquifer spring 2 (LKAS 2) constitutes a typical limestone karst aquifer spring with a dynamic hydrological regime and discharge. Dolomite karst aquifer spring 1 yielded constantly lower cell counts and biomasses (median of 15 x 10(6) cells l(-1) and 0.22 mu g C l(-1)) as the LKAS 2 (median of 63 x 10(6) cells l(-1) and 1.1 mu g C l(-1)) and distribution of morphotypes and mean cell volumes was also different between the considered systems, indicating the influence of hydrogeology on microbial spring water quality. Molecular bacterial V3 16S-rDNA profiles revealed remarkable constancy within each spring water throughout the investigation period. Time course analysis of a flood event in LKAS 2 further supported the trend of the temporal constancy of the microbial community. Except for one case, retrieval of partial and full length 16S rDNA gene sequences from the relative constant DKAS 1 revealed similarities to presently known sequences between 80% to 96%, supporting the discreteness of the microbial populations. The gathered results provide first evidence for the presence of autochthonous microbial endokarst communities (AMEC). Recovery of AMEC may be considered of relevance for the understanding of alpine karst aquifer biogeochemistry and ecology, which is of interest as many alpine and mountainous karst springs are important water resources throughout the world

Geomicrobiology of cave ferromanganese deposits: A field and laboratory investigation, 2005, Spilde M. N. , Northup D. E. , Boston P. J. , Schelble R. T. , Dano K. E. , Crossey L. J. , Dahm C. N. ,
Unusual ferromanganese deposits are found in several caves in New Mexico. The deposits are enriched in iron and manganese by as much as three orders of magnitude over the bedrock, differing significantly in mineralogy and chemistry from bedrock-derived insoluble residue. The deposits contain metabolically active microbial communities. Enrichment cultures inoculated from the ferromanganese deposits produced manganese oxides that were initially amorphous but developed into crystalline minerals over an 8-month period and beyond; no such progression occurred in killed controls. Phylogenetic analyses of sequences from clone libraries constructed from culture DNA identified two genera known to oxidize manganese, but most clones represent previously unknown manganese oxidizers. We suggest that this community is breaking down the bedrock and accumulating iron and manganese oxides in an oligotrophic environment

Technical impracticability of DNAPL remediation in karst, 2005, Kresic N. , O'laskey R. , Deeb R. Et Al.

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, ...)

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

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

Dominant Microbial Populations in Limestone-Corroding Stream Biofilms, Frasassi Cave System, Italy, 2006, Macalady Jennifer L. , Lyon Ezra H. , Koffman Bess, Albertson Lindsey K. , Meyer Katja, Galdenzi Sandro, Mariani Sandro,
Waters from an extensive sulfide-rich aquifer emerge in the Frasassi cave system, where they mix with oxygen-rich percolating water and cave air over a large surface area. The actively forming cave complex hosts a microbial community, including conspicuous white biofilms coating surfaces in cave streams, that is isolated from surface sources of C and N. Two distinct biofilm morphologies were observed in the streams over a 4-year period. Bacterial 16S rDNA libraries were constructed from samples of each biofilm type collected from Grotta Sulfurea in 2002. {beta}-, {gamma}-, {delta}-, and {varepsilon}-proteobacteria in sulfur-cycling clades accounted for [≥]75% of clones in both biofilms. Sulfate-reducing and sulfur-disproportionating {delta}-proteobacterial sequences in the clone libraries were abundant and diverse (34% of phylotypes). Biofilm samples of both types were later collected at the same location and at an additional sample site in Ramo Sulfureo and examined, using fluorescence in situ hybridization (FISH). The biomass of all six stream biofilms was dominated by filamentous {gamma}-proteobacteria with Beggiatoa-like and/or Thiothrix-like cells containing abundant sulfur inclusions. The biomass of {varepsilon}-proteobacteria detected using FISH was consistently small, ranging from 0 to less than 15% of the total biomass. Our results suggest that S cycling within the stream biofilms is an important feature of the cave biogeochemistry. Such cycling represents positive biological feedback to sulfuric acid speleogenesis and related processes that create subsurface porosity in carbonate rocks

Barka depression, a denuded shaft in the area of Snez?nik Mountain, southwest Slovenia, 2007, Zupan Hajna N.
On the southern slope of Dedna gora, Slovenia, at an elevation of 1147 m, an interesting large closed depression referred to as Barka (Barge) is developed. It is about 40 m long, 25 m wide and 20 m deep, with smooth, almost polished precipitous walls. It is developed in Upper Cretaceous limestones and affected by several faults and fissure zones. The feature lies within a large karren field (about 104 m2) with many closed depressions of various dimensions. In the winter time, snow accumulates in the bottoms giving the appearance of snow-kettles, such as those found in the Alps. The size and especially the shape of the walls suggests that these features are the remains of shafts. After their primary genesis as the inner vadose shafts of one or more caves, their upper parts would have been denuded. Walls and bottoms were subsequently remodeled by snow and ice action during the last glaciations, and this continues today as winter snow accumulates at their bottoms. This is indicated by silt fragments (gelifraction) and frost rubble accumulated in portions of the depression, and the development of sorted and nonsorted polygons. Shafts that have been exposed at the surface are a potentially important morphological element of karst topography. They can represent a significant portion of closed depressions of different sizes, including many snow-kettles.

How long does evolution of the troglomorphic form take? Estimating divergence times in Astyanax mexicanus, 2007, Porter M. L. , Dittmar K. , Pé, Rezlosada M.

Features including colonization routes (stream capture) and the existence of both epigean and cave-adapted hypogean popula­tions make Astyanax mexicanus an attractive system for investi­gating the subterranean evolutionary time necessary for acqui­sition of the troglomorphic form. Using published sequences, we have estimated divergence times for A. mexicanus using: 1) two different population-level mitochondrial datasets (cyto­chrome b and NADH dehydrogenase 2) with both strict and relaxed molecular clock methods, and 2) broad phylogenetic approaches combining fossil calibrations and with four nuclear (recombination activating gene, seven in absentia, forkhead, and α-tropomyosin) and two mitochondrial (16S rDNA and cytochrome b) genes. Using these datasets, we have estimated divergence times for three events in the evolutionary history of troglomorphic A. mexicanus populations. First, divergence among cave haplotypes occurred in the Pleistocene, possibly correlating with fluctuating water levels allowing the coloni­zation and subsequent isolation of new subterranean habitats. Second, in one lineage, A. mexicanus cave populations expe­rienced introgressive hybridization events with recent surface populations (0.26-2.0 Ma), possibly also correlated with Pleis­tocene events. Finally, using divergence times from surface populations in the lineage without evidence of introgression as an estimate, the acquisition of the troglomorphic form in A. mexicanus is younger than 2.2 (fossil calibration estimates) – 5.2 (cytb estimate) Ma (Pliocene).

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