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Enviroscan Ukrainian Institute of Speleology and Karstology

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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 lava karst is a non-karst term. subsurface openings formed in lava flows due to outflow of liquid lava from beneath a solidified crust or due to gas blisters. tubes or tunnels are formed with such pseudokarst features as lava stalactites and also collapse structures and basins of closed drainage. lava karst does not arise through solution of the rock by circulating water and thus is not a true karst [20]. synonyms: (french.) pseudo-karst; (german.) (vulkanischer karst), lava- karst, pseudokarst; (greek.) pseudokarst; (italian.) pseudocarsismo vulcanico; (spanish.) volcanokarst (general), tubo volcanico (tube, tunnel), jameo (collapse structure), malpais (topographic feature similar to lapies); (turkish.) lav karsti, a ldatici karst. see also lava cave; pseudokarst.?

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.
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;
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Your search for baseflow (Keyword) returned 33 results for the whole karstbase:
Showing 1 to 15 of 33
Anomalous behaviour of specific electrical conductivity at a karst spring induced by variable catchment boundaries: the case of the Podstenjšek spring, Slovenia, ,
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Ravbar, N. , Engelhardt, I. , Goldscheider, N.

Anomalous behaviour of specific electrical conductivity (SEC) was observed at a karst spring in Slovenia during 26 high-flow events in an 18-month monitoring period. A conceptual model explaining this anomalous SEC variability is presented and reproduced by numerical modelling, and the practical relevance for source protection zoning is discussed. After storm rainfall, discharge increases rapidly, which is typical for karst springs. SEC displays a first maximum during the rising limb of the spring hydrograph, followed by a minimum indicating the arrival of freshly infiltrated water, often confirmed by increased levels of total organic carbon (TOC). The anomalous behaviour starts after this SEC minimum, when SEC rises again and remains elevated during the entire high-flow period, typically 20–40 µS/cm above the baseflow value. This is explained by variable catchment boundaries: When the water level in the aquifer rises, the catchment expands, incorporating zones of groundwater with higher SEC, caused by higher unsaturated zone thickness and subtle lithologic changes. This conceptual model has been checked by numerical investigations. A generalized finite-difference model including high-conductivity cells representing the conduit network (“discrete-continuum approach”) was set up to simulate the observed behaviour of the karst system. The model reproduces the shifting groundwater divide and the nearly simultaneous increase of discharge and SEC during high-flow periods. The observed behaviour is relevant for groundwater source protection zoning, which requires reliable delineation of catchment areas. Anomalous behaviour of SEC can point to variable catchment boundaries that can be checked by tracer tests during different hydrologic conditions.

Paleohydrology and Streamflow Simulation of three Karst Basins in Southeastern West Virginia, U.S.A., PhD Thesis, 1975,
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Coward, Julian Michael Henry

This study was undertaken to gain a better understanding of karst hydrology. To do this, the present day hydrology and the paleohydrology were determined in three karst basins. The basins chosen were the Swago, Locust and Spring Creek basins in Pocahontas and Greenbrier Counties, West Virginia. A number of conventional field techniques were used successfully in this study, including the following: current meter and dye dilution gauging; dye and lycopodium stream tracing; geological and cave mapping; the setting up of stage recorders; geochemistry; and limestone erosion measurements. The climate of the region was investigated to obtain realistic precipitation, temperature and potential evaporation data over the study basins.
It was found that the mean precipitation over two of the basins was 30% higher than recorded data in the valleys. The karst development of the basins was found to take place in four major stages. These were: A) initial surficial flow, B) strike controlled drainage, C) major piracies from one sub-basin to another, and D) shortening of the flow routes. The major controls on the karst development were found to be: A) the Taggard shale, B) the strike direction, which controlled early basin development, and C) the hydraulic gradient from the sink to rising, which controlled later basin development.
To better assess the quantitative hydrology, and to assist in determining the type of unexplorable flow paths, a watershed model was developed. This modelled the streamflow from known climatic inputs using a number of measured or optimized parameters. The simulation model handled snowmelt, interception, infiltration, interflow, baseflow, overland flow, channel routing, and evaporation from the interception, soil water, ground water, snowpack and channel water. The modelled basin could be split up into 20 segments, each with different hydrological characteristics, but a maximum of 3 segments was used in this study.
A total of 29 parameters was used in the model although only 10 (other than those directly measurable) were found to be sensitive in the three basins. The simulated streamflow did not match the real flows very well due to errors in the data input and due to simplifications in the model. It was found, however, that as the proportion of the limestone in a segment increased the overland flow decreased, the interflow increased, the baseflow and interflow recessions were faster, the soil storages were smaller and the infiltration rate was higher, than in segments with a larger proportion of exposed clastics. The flow characteristics of the inaccessible conduits were inferred from the channel routing parameters and it was postulated that the majority of the underground flow in the karst basins was taking place under vadose conditions.

Hydrology and hydrochemistry of the Caves Branch karst, Belize, 1983,
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Miller T. ,
A large conduit spring issuing from Cretaceous limestones in Belize, Central America, displays a positive relation of discharge to solute concentration. Beneath a maturely-dissected cockpit karst, the hydrologic system combines allogenic surface water from an invasion polje with authigenic karst water. Dynamic mixing produces three climatically-induced discharge phases: baseflow, normal, and high-stage flow. Each has an associated hydrochemical regime, predominantly diffuse-flow karst water. An areal solute concentration of ~80 mg l-1 Ca2 is estimated, with a “denudation rate” of 100 mm per 1000 yr

The role of the subcutaneous zone in karst hydrology, 1983,
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Williams Paul W. ,
The subcutaneous zone is the upper weathered layer of rock beneath the soil, but above the permanently saturated (phreatic) zone. It is of particular hydrological importance in karst because of its high secondary permeability, arising from the considerable chemical solution in this zone. However, corrosional enlargement of fissures diminishes with depth; thus permeability decreases in the same direction with the result that percolation is inhibited, except down widened master joints and faults. Storage of water consequently occurs in this zone, particularly after storms. The upper surface of this suspended saturated layer in the subcutaneous zone is defined by a perched water table, which slopes towards points of rapid vertical percolation. The potential induces lateral water movement converging on the most permeable areas such as beneath dolines. Leakage from the subcutaneous store sustains slow percolation in the vadose zone. Cross-correlation of rainfall with percolation rates in caves in New Mexico, U.S.A., and New Zealand reveal response lags of 2-14 weeks with no apparent relationship to depth below the surface. Other percolation sites show no correlation with rainfall; interpreted as being a consequence of considerable friction in tight fissure networks. The recognition of storage and rapid as well as very slow percolation from the subcutaneous zone requires re-interpretation of the components of hydrographs from karst springs and of some conceptual models of karst aquifers. The importance of subcutaneous storage in sustaining baseflow discharge at some sites must be recognised, as must the contribution of subcutaneous water to flood hydrographs. Methods of estimating the volumes of subcutaneous and phreatic components of karst-spring flood hydrographs are presented. The paper concludes with a discussion of the significance of subcutaneous hydrologic processes for an understanding of karst geomorphology. The desirability of explaining karst landform evolution in terms of hydrologic processes is stressed

Further Studies at the Blue Waterholes, Cooleman Plain, N.S.W., 1969-77, Part I, Climate and Hydrology, 1983,
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Jennings, J. N.

Previous study of the temporal and spatial distribution of limestone solution at Cooleman Plain rested on monthly discharges and water analyses of the Blue Waterholes over 4 years. For this study automatic recording of discharge (8 years), rainfall (8 years), evaporation (7 years) and temperature (4 years) was attended by variable success in the face of interference, rigorous climate and inaccessibility. The most important aspect of the climatic data was the support obtained for the earlier assumption of similar water balances in the forested igneous frame and the grassland limestone plain. Runoff was again shown to be highly variable from year to year and to have an oceanic pluvial regime, with a summer-autumn minimum owing much to evapo-transpiration. The flow duration curve from daily discharges puts this karst amongst those where neither extremely high nor low flows are important. The stream routing pattern offsets the effect of 71% of the catchment being on non-karst rocks, damping flood events. An inflection of 700 l/s in a flow duration plot based on discharge class means is interpreted as the threshold at which surface flow down North Branch reaches the Blue Waterholes. Storages calculated from a generalised recession hydrograph parallel Mendip data where baseflow (fissure) storage provides most of the storage and quickflow (vadose) storage only a secondary part. Water-filled conduit storage (the phreas) could not be determined but is considered small. The baseflow storage seems large, suggesting that it can develop independently of caves in some measure. A quickflow ratio for floods derived by Gunn's modification of the Hewlett and Hibbert separation line method appears relatively low for a mainly non-karst catchment and is again attributed to the routing pattern. For analysis of variation of the solute load over time, estimates of daily discharge during gaps in the record where made for the author by Dr. A.J. Jakeman and Mr. M.A. Greenaway (see Appendix). A small number of discharge measures of two contrasted allogenic catchments of the igneous frame shows a unit area yield close to that for the whole catchment. Together with the guaging of most of the allogenic inputs, this supports the idea that the water yield is much the same from the forested ranges and the grassland plain. This is important for the estimation of limestone removal rates.

A reconnaissance isotope study of waters in the karst of the Western Tatra mountains, 1988,
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Rozanski K. , Dulinski M. ,
Presented are results of isotope investigations of waters collected in the karstic area of the Western Tatra Mts. Altogether 35 groundwater samples have been analysed (tritium content, [delta]D, [delta]18O). They represent groundwaters collected on the earth surface (springs, streams, exurgences) as well as waters found in caves. Parallel, systematic isotope analyses of monthly precipitation collected at the Ornak station located in the center of the investigated area were also carried out. The results of isotope investigations fully confirm earlier suggestions that the karst system of the Western Tatra Mts consists of separate independent subsystems exhibiting weak (if any) hydraulic interconnections. Tritium data allow a semi-quantitative assessment of the mean residence time of the baseflow component in the investigated system. It is equal to at least 7/8 years. Eventual further measurements of tritium content should allow a more precise determination of this parameter. [delta]D and [delta]18O analyses of the investigated waters provide a basis for assessment of the Is/I ratio i.e. the ratio of infiltration originating from summer precipitation to the total yearly infiltration. It appears that groundwaters collected in caves exhibit on the average significantly higher D and 18O content compared to groundwaters collected on the surface. Possible reasons of this effect are discussed thoroughly in the paper

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Padilla A. , Pulidobosch A. , Mangin A. ,
Evaluation of recession hydrographs, from four karst springs in Europe, provides important information concerning the flow process operating in karst aquifer systems. Three analytic equations are used to evaluate the hydrographs: Mangin's equation, that assumes the recession is composed of both quickflow and baseflow; Coutagne's equation which considers the recession to be the response of a single reservoir; and a new function, H(t) (which is derived from Coutagne's equation), that refers to the whole recession curve. Using Mangin's equation it is apparent that the saturated zone and thus baseflow exerts nearly complete control over the discharge of La Villa spring and is fairly important at Fuente Mayor and Baget springs, but is much less significant at Aliou spring. The saturated zone accounts for 100%, 90%, 91%, and 40% respectively for these springs. Using Coutagne's equation and H(t) it is concluded that for Aliou and Baget springs, water flows freely in the high transmissive zones, but in the poorly transmissive zones, there is little continuity of connection in the system. At Fuente Mayor spring the differences in these zones are not so apparent and a gradual transition occurs. However, at La Villa spring, the karst aquifer is evidently much more homogeneous and the discharge is similar to that of a porous intergranular aquifer

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Pulidobosch A. , Padilla A. , Dimitrov D. , Machkova M. ,
The discharge variability of some karst springs in Bulgaria has been investigated in detail within a region situated in the semiarid zone where most of the principal processes controlling spring outflow (evapotranspiration, snow accumulation, karstic functioning) are significant. While the karstification was notable in the Kotel and Bistretz springs with a predominance of quickflow, in the Beden system the baseflow was higher and had a behaviour similar to a porous aquifer. Univariate and bivariate spectral analyses were applied as a suitable tool in preparation for a further application of precipitation-discharge relationship models

Discussion on 'The Chalk as a karstic aquifer: evidence from a tracer test at Stanford Dingley, Berkshire, UK': Quarterly Journal of Engineering Geology, 28, S31-S38, 1996,
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Banks D, Davies C, Davies W,
M. Price writes: Banks et al. (1995) address the nature of the permeability of parts of the Chalk aquifer, provide useful data from a tracer test, and draw attention to the potential dangers of disposing of agricultural and road run-off to swallow holes. The paper includes a calculation of fissure conductivity and aperture from the results of the tracer test. In this it has to be emphasized that the calculations relate to Darcian flow in an equivalent smooth, plane, parallel-plate opening, not the more likely turbulent flow in a natural fissure. The true average aperture of the fissure is therefore likely to be significantly greater than that calculated (Price 1987, 1996). The situation described at Stanford Dingely is one where drainage originating from impermeable Tertiary strata flows onto the Chalk and sinks into the aquifer. The majority of active Chalk sinks appear to be of this type; the drainage sinking into them originates as run-off from other strata. Rain falling anywhere on the outcrop of the Chalk is normally able to infiltrate, so water flowing across the Chalk outcrop is almost invariably allogenic drainage or water that has infiltrated the Chalk and emerged as baseflow. Drainage to sinks is therefore a minor component of recharge to the Chalk. The tracer test undertaken into at Stanford Dingley involved introducing tracer into a known point of entry in the aquifer, and observing its arrival at a known point of emergence. Such tests almost inevitably measure the speed of groundwater movement along a ... This 250-word extract was created in the absence of an abstract

Aufeis of the Firth River basin, Northern Yukon Canada: Insights into permafrost hydrogeology and Karst, 1997,
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Clark Id, Lauriol B,
The 31-km(2) aufeis ice sheet of the upper Firth River holds a wealth of information on groundwater hydrology in periglacial environments. Baseflow recession calculations, corrected for aufeis storage (12% of basin discharge), indicate specific groundwater recharge rates of up to 100 mm yr(-1) (up to 50% of runoff), suggesting a significant proportion of drainage from karst. The upper Firth River aufeis is a composite aufeis, with discrete baseflow contributions from different watersheds. Since the late Pleistocene, annual growth of the aufeis has exerted a strong control on lateral erosion and the local river channel geomorphology. Two groundwater recharge processes are distinguished on the basis of carbonate geochemistry and 8(13)C: (1) Methanogenic groundwaters, with C-13(DIC) up to -3.3 parts per thousand, are recharged through saturated soils underlain by permafrost; conditions which support anaerobic consumption of dissolved organic carbon (DOC) and produce up to 700 mu g-CH4 L-1 (calculated), and (2) Karst groundwaters, with C-13-depleted DIC, recharged through unsaturated soils and circulate through fissured talik in the carbonate bedrock. Most drainage from the region shows varying contributions of these two groundwaters, although a greater contribution from the methanogenic groundwaters occurs in north-facing watersheds. The 8(13)C values far cryogenic calcite precipitates in the ice indicate that the karst groundwaters are the major contribution to aufeis growth. The combined use of 8(13)C(DIC) and geochemistry may be a useful tool to quantify methanogenesis in northern watersheds

Numerical simulation as a tool for checking the interpretation of karst spring hydrographs, 1997,
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Eisenlohr L, Kiraly L, Bouzelboudjen M, Rossier Y,
A schematic representation of karst aquifers may be that of a high hydraulic conductivity channel network with kilometre-wide intervals, surrounded by a low hydraulic conductivity fractured limestone volume and connected to a local discharge area, the karst spring, The behaviour of the karst spring (hydrographs, chemical or isotopic composition, etc.) represents the global response of the karst aquifer to input events. The available data an karst aquifer hydraulic parameters are limited, Global response is therefore more easily obtained and is commonly used to make inferences on the recharge and groundwater How processes, as well as on the hydraulic parameter fields. Direct verification of these interpretations is, obviously, very difficult. We have used an indirect method of verification, consisting of introducing well-defined theoretical karst structures into a finite element model and then analysing the simulated global response according to presently accepted interpretation schemes. As we know what we put into the numerical model, the validity of any interpretation may be checked. The first results indicate that some of the generally accepted interpretations are not necessarily true. In particular: (i) separation of simulated recession hydrographs into several components shows that different exponential components do not necessarily correspond to aquifer volumes with different hydraulic conductivities: (ii) non-exponential parts of recession hydrographs do not always give information about the infiltration process: and (iii) the recession coefficient of the baseflow (i.e. the last, nearly exponential part of the recession hydrograph) depends on the global configuration of the whole karst aquifer, not just on the hydraulic properties of the low hydraulic conductivity volumes. (C) 1997 Elsevier Science B.V

Hydrologic analysis of discharge sustainability from an abandoned underground coal mine, 2000,
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Burbey Tj, Younos T, Anderson Et,
Discharge from flooded abandoned subsurface coal mines is considered a potential source for water supplies where other acceptable water sources are not available. The objective of this study was to develop procedures for determining sustainability of mine-water discharge using rainfall and discharge data for a case study site. The study site is located in southwest Virginia where Late Paleozoic sequences of sandstone, coal, and shale predominate. A rain gauge and a flow rate monitoring system were installed at the site and data were collected for a period of 100 days. The recording period corresponded with one of the driest periods in recent years and, therefore, provided valuable information regarding the flow sustainability during baseflow conditions. From available data on underground mining patterns, geology, and ground water flow regimes, it was determined that a coal mine aquifer exhibits hydraulic characteristics very similar to the extremely heterogeneous systems observed in karst aquifers, and the mine discharge is analogous to springflow. Thus, techniques commonly used in karst-water systems and springflow analysis were used to develop rainfall/mine-discharge relationships. Springflow recession analysis was performed on five rainfall recessions and the coefficient for each recession was compared and interpreted in light of known geologic information. It was found that the recession coefficients described the mine discharge adequately and the mine aquifer response to a rainfall pulse was very similar to the response from certain ts;pes of karst aquifers. A cross-correlation analysis was performed to verify the results of the recession analysis and to develop a 'black box' statistical model for discharge data. The correlation analysis proved the validity of springflow recession analysis for mine discharge. The recorded data length was not adequate to create a statistical model, however, but a procedure was proposed for a statistical model that could be used with large flow records. For the study site, the mine discharge was found to be sustainable for a prolonged period of time

Simulation of daily and monthly stream discharge from small watersheds using the SWAT model, 2000,
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Spruill C. A. , Workman S. R. , Taraba J. L. ,
The Soil and Water Assessment Tool (SWAT) was evaluated and parameter sensitivities were determined while modeling daily streamflows in a small central Kentucky watershed over a two-year period. Streamflow data from 1996 were used to calibrate the model and streamflow data from 1995 were used for evaluation. The model adequately predicted the trends in daily streamflow during this period although Nash-Sutcliffe R-2 values were -0.04 and 0.19 for 1995 and 1996, respectively The model poorly predicted the timing of some peak flow values and recession rates during the last half of 1995. Excluding daily peak flow values from August to December improved the daily R-2 to 0.15, which was similar to the 1996 daily R2 value. The Nash-Sutcliffe R-2 for monthly total flows were 0.58 for 1995 and 0.89 for 1996 which were similar to values found in the literature. Since very little information was available on the sensitivity of the SWAT model to various inputs, a sensitivity analysis/calibration procedure was designed to evaluate parameters that were thought to influence stream discharge predictions. These parameters included, drainage area, slope length, channel length, saturated hydraulic conductivity, and available water capacity. Minimization of the average absolute deviation between observed and simulated streamflows identified optimum values/ranges for each parameter. Saturated hydraulic conductivity alpha baseflow factor; drainage area, channel length, and channel width were the most sensitive parameters in modeling the karst influenced watershed. The sensitivity analysis process confirmed die trace studies in the karst watershed that a much larger area contributes to streamflow than can be described by the topographic boundaries. Overall, the results indicate that the SWAT model can be an effective tool for describing monthly, runoff from small watersheds in central Kentucky that have developed on karat hydrology however calibration data are necessary to account for solution channels draining into or out of the topographic watershed

Hydrogeological characteristics of a karst mountainous catchment in the northwest of Vietnam, 2001,
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Tam V. T. , Vu T. M. N. , Batelaan O. ,
This paper presents a preliminary assessment of the hydrogeological characteristics of a karst mountainous catchment, the Suoi Muoi River catchment, in the northwest of Vietnam. The catchment is located at 600 -700 in a.s.l. and covers an area of 284 kin. Exposed limestone occupies 32% of the total catchment area. Various types of assessments have been carried out, including geological and hydrogeological. field surveys, cave surveys, dye-tracer tests, meteorological and surface water monitoring. Geological studies and cave surveys have identified the most important active cave/conduit systems within the catchment. Although these data are essential, they are insufficient to make a comprehensive appraisal of the hydrologic nature of the catchment under interest. An attempt was made to calculate a global water balance of the catchment, based on short-term (15 months) meteorological and streamflow records. The results show that, despite the existence of a number of substantial cavern conduit systems, the groundwater system of the catchment is governed by the fracture/fissure matrix. The cavern conduit systems only collect groundwater from the adjacent fracture matrix and/or connect topographically isolated surface watercourses. The groundwater storage of the cavern conduit systems appears to be regionally insignificant in comparison with the governed fracture matrix groundwater system

Spatial and temporal patterns of bacterial density and metabolic activity in a karst aquifer, 2001,
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Simon K. S. , Gibert J. , Petitot P. , Laurent R. ,
Karst aquifers are heterotrophic ecosystems fueled by organic matter imported from the surface. The temporal pattern of floods influences organic matter import and the spatial distribution of organic matter and biofilms in aquifer structural zones. We investigated spatial and temporal patterns of bacterial density and activity as indicators of energy availability and microbial dynamics in a karst aquifer. During baseflow, bacterial density and microbial hydrolytic activity were similar in the upper and lower zones of the aquifer. Floods apparently scoured aquifer biofilms and trans ported soil bacteria into the aquifer, increasing inactive bacterial density in the water column. Respiring bacterial density did not respond to floods and changed little over time. The overall proportion of total bacteria that were respiring was very high on some dates, resulting from a reduction of inactive cell density during flood recession. Floods appear to be key events in scouring senescent microbial assemblages in karst aquifers and stimulating microbial recolonization of the aquifer matrix. We conclude that a conceptual model of karst aquifer structure and function should incorporate changes caused by alternation between flooding and drying in the aquifer

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