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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 turbulent flow is 1. type of flow that begins to develop in a dissolutional sub-conduit as its diameter increases to the point where differences between flow velocity at the bounding wall (slowed due to friction and adhesion) and the maximum velocity in the tube's center are sufficient to cause development of eddies within the flowing water [9]. 2. the flow condition in which inertial forces predominate over viscous forces and in which head loss is not linearly related to velocity [22]. it is typical of flow in surface-water bodies and subsurface conduits in karst terranes provided that the conduits have a minimum diameter of approximately 2-5mm although some research has suggested that 5-15 mm may be more appropriate. see also laminar flow; reynolds number; turbulent threshold.?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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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 drip rate (Keyword) returned 28 results for the whole karstbase:
Showing 16 to 28 of 28
Monitoring climatological, hydrological and geochemical parameters in the Pre Nol cave (Belgium): implication for the interpretation of speleothem isotopic and geochemical time-series, 2008, Verheyden S. , Genty D. , Deflandre G. , Quinif Y. And Keppens E.
Pre Nol cave climatology (air and water temperature, PCO2), hydrology (drip rate, conductivity) and geochemistry of water and calcite deposits (?18O, ?13C, Mg/Ca and Sr/Ca) where studied to better interpret stable isotopic and trace element variations of speleothems. Results of an automated monitoring station and of manual sampling between 1991 and 1998 have demonstrated the highly seasonal signal of drip rate, its control by water excess and rainfall, and, at a shorter scale to air pressure changes. The modern calcite deposit study suggests a relationship between cave calcite isotopic composition (?18O and ?13C) and drip rate likely due to variations in degree of isotopic equilibrium during calcite precipitation. ?18O and ?13C of the calcite are therefore, through drip rate, linked to water recharge. Mg/Ca and Sr/Ca ratios of Pre Nol cave calcite, depend closely on the residence time of the water, and therefore are also linked to drip rate and therefore to water recharge. This crossed link of ?18O and ?13C as of Mg/Ca and Sr/Ca to water recharge may explain the very similar variations of these four parameters along the longitudinal axis of a Holocene stalagmite, but it may also be the consequence of kinetic effects during calcite precipitation as suggested by similar variations of the four parameters along a single layer of the Holocene stalagmite.

Hydrogeochemical processes as environmental indicators in drip water: Study of the Cueva del Agua (Southern Spain), 2008, Fernandezcortes A. , Calaforra J. M. , Snchezmartos F.

Karst caves exhibit a wide range of hydrological and hydrochemical responses to infiltration events, due to their physical heterogeneity space and dynamic variability over time, and due to non-Gaussian inputs (rain) and outputs (discharge). This paper reviews different approaches of studying seepage water in caves, in order to understand the infiltration regimen in the non-saturated zone of karst areas. As an illustration, we describe a four-year study of the active carbonate-water system the Cueva del Agua (Granada, southern Spain) that automatically logs the discharge from a stalactite. The results indicate that: (1) the drip water regime is not seasonal, but is linked instead to slow infiltration. Sudden changes in drip water regime occur due to infiltration along preferential flow paths and the draining of water of supersaturated water from reserves in the microfissure and pore system; (2) the drip rate is not linear over time. When dripping is constant, barometric oscillation of the air is the principal factor causing a chaotic a drip flow regime. Over a short period of two to three days, a mean variation in air pressure inside the cave of 10 (±3.7) mbar causes a oscillation the drip rate of 0.5 (±0.2) mm/h. The increase air translates into an the relative thickness of the gaseous phase of the drip water at the cost of the aqueous phase, so leading to a reduction the drip rate from the stalactite.


Report of a three-year monitoring programme at Heshang Cave, Central China, 2008, Hu C. , Henderson G. M. , Huang J. , Chen Z. , Johnson K. R.

Heshang Cave is situated in central China (30º27’N, 110º25’E; 294 m) in the middle reaches of the Yangtze Valley, a region strongly impacted by the East Asian Monsoon. It contains large annually-laminated Holocene and late Pleistocene stalagmites which capture past monsoon behaviour with seasonal resolution, and could enhance understanding of the amplitude and frequency of monsoon behaviour in different climate states. In this paper, we present results of a 3-year monitoring programme at Heshang. T loggers outside the cave agree closely with T data from nearby meteorological stations. T at the site of growth of the largest recovered stalagmite averages 18ºC (identical to mean annual T outside the cave) with a seasonal amplitude of 5ºC (about one fifth of the external cycle). Rainfall measurements from a station 3 km from the cave indicate strong summer monsoon rain in 2004 and 2005, but rather weaker summer rain (by ≈30%) in 2006. Drip rate at the monitoring site has a base flow of 14 drips/minute and shows a sharp increase to ≈40 drips/minute early in the summer rains of 2004 and 2005, followed by a gradual return to base-flow as the monsoon weakens. This abrupt change presumably represents threshold behaviour in the hydrological system. This threshold is not passed in 2006 and there is no abrupt increase in drip rate, indicating the sensitivity of this site (and presumably of speleothem chemistry in this cave) to monsoon rainfall. Results are also reported from a 10-month deployment of a Stalagmate drip counter, and for CO2 levels in Heshang Cave. Overall, this monitoring work represents an essential dataset for interpretation of the chemistry of drip waters, of carbonates grown on glass slides and, ultimately, of long speleothem records of past climate from Heshang Cave.


Palaeoclimate Research in Villars Cave (Dordogne, SW-France), 2008, Genty, D.

Villars Cave is a typical shallow cave from South-West France (45.44°N; 0.78°E; 175 m asl) that has provided several speleothem palaeoclimatic records such as the millennial scale variability of the Last Glacial period and the Last Deglaciation. Monitoring the Villars cave environment over a 13-year period has helped in the understanding of the stable isotopic speleothem content and in the hydrology. For example, it was demonstrated that most of the calcite CaCO3 carbon comes from the soil CO2, which explains the sensitivity of the δ13C to any vegetation and climatic changes. Drip rate monitoring, carried out under four stalactites from the lower and upper galleries, has shown a well marked seasonality of the seepage water with high flow rates during winter and spring. A time delay of about two months is observed between the water excess (estimated from outside meteorological stations) and the drip rate in the cave. A great heterogeneity in the flow rate amplitude variations and in the annual quantity of water between two nearby stalactites is observed, confirming the complexity of the micro-fissure network system in the unsaturated zone. At a daily scale, the air pressure and drip rates are anti-correlated probably because of pressure stress on the fissure network. Cave air CO2 concentration follows soil CO2 production and is correlated with its δ13C content. Since the beginning of the monitoring, the cave air temperature, in both lower and upper galleries, displays a warming trend of ~+0.4°C±0.1/10yrs. This might be the consequence of the outside temperature increase that reaches the Villars Cave galleries through thermal wave conduction. Chemistry monitoring over a few years has shown that the seepage water of the lower gallery stations is significantly more concentrated in trace and minor elements (i.e. Sr, Mg, Ba, U) than the upper stations, probably due to the 10-20 m depth difference between these galleries, which implies a different seepage pathway and different water/rock interaction durations. There is also, in the elemental concentration (i.e. [Ca]), a seasonal signal which causes variation in the speleothem growth rates. Modern calcite deposit experiments conducted for several years have permitted the calculation of vertical growth rates, which are extremely high in Villars (i.e. 1.0 to 1.75 mm/yr). Pollen filter experiments in the cave have demonstrated that most of the pollen grain found in the cave comes from the air and not from the water. The specificity of the Villars Cave records is that the climatic variations were well recorded in the calcite δ13C whereas the δ18O is usually used in such studies. Overall, these results are helpful for the interpretation of speleothem records for palaeoclimatic reconstructions, but more work is needed, especially numerical modelling of the temperature, chemistry and hydrology.


Monitoring climatological, hydrological and geochemical parameters in the Pre Nol cave (Belgium): implication for the interpretation of speleothem isotopic and geochemical time-series, 2008, Verheyden S. , Genty D. , Deflandre G. , Quinif Y. , Keppens E.

Père Noël cave climatology (air and water temperature, PCO2), hydrology (drip rate, conductivity) and geochemistry of water and calcite deposits (δ18O, δ13C, Mg/Ca and Sr/Ca) where studied to better interpret stable isotopic and trace element variations of speleothems. Results of an automated monitoring station and of manual sampling between 1991 and 1998 have demonstrated the highly seasonal signal of drip rate, its control by water excess and rainfall, and, at a shorter scale to air pressure changes. The modern calcite deposit study suggests a relationship between cave calcite isotopic composition (δ18O and δ13C) and drip rate likely due to variations in degree of isotopic equilibrium during calcite precipitation. δ18O and δ13C of the calcite are therefore, through drip rate, linked to water recharge. Mg/Ca and Sr/Ca ratios of Père Noël cave calcite, depend closely on the residence time of the water, and therefore are also linked to drip rate and therefore to water recharge. This crossed link of δ18O and δ13C as of Mg/Ca and Sr/Ca to water recharge may explain the very similar variations of these four parameters along the longitudinal axis of a Holocene stalagmite, but it may also be the consequence of kinetic effects during calcite precipitation as suggested by similar variations of the four parameters along a single layer of the Holocene stalagmite.


δ13C profiles along growth layers of stalagmites: Comparing theoretical and experimental results, 2008, Romanov D. , Kaufmann G. , Dreybrodt W.

The isotopic carbon ratio of a calcite-precipitating solution flowing as a water film on the surface of a stalagmite is determined by Rayleigh distillation. It can be calculated, when the -concentration of the solution at each surface point of the stalagmite and the fractionation factors are known. A stalagmite growth model based entirely on the physics of laminar flow and the well-known precipitation rates of a supersaturated solution of calcite, without any further assumptions, is employed to obtain the spatial distribution of the -concentration, which contributes more than 95% to the dissolved inorganic carbon (DIC). The δ13C profiles are calculated along the growth surface of a stalagmite for three cases: (A) isotopic equilibrium of both CO2 outgassing and calcite precipitation; (B) outgassing of CO2 is irreversible but calcite precipitation is in isotopic equilibrium. (C) Both CO2 outgassing and calcite precipitation are irreversible. In all cases the isotopic shift δ13C increases from the apex along the distance on a growth surface. In cases A and B, calcite deposited at the apex is in isotopic equilibrium with the solution of the drip water. The difference between δ13C at the apex and the end of the growth layer is independent of the stalagmite’s radius, but depends on temperature. For case A, it is about half the value obtained for cases B and C. In case C, the isotopic composition of calcite at the apex equals that of the drip water, but further out it becomes practically identical with that of case B. The growth model has been applied to field data of stalagmite growth, where the thickness and the δ13C of calcite precipitated to a glass plate located on the top of a stalagmite have been measured as function of the distance from the drip point. The calculated data are in good agreement to the observed ones and indicate that deposition occurred most likely under conditions B, eventually also C. A sensitivity analysis has been performed, which shows that within the limits of observed external parameters, such as drip rates and partial pressure of carbon dioxide PCO2 in the cave, the results remain valid.


Impacts of Alterations of Organic Inputs on the Bacterial Community within the sediments of Wind Cave, South Dakota, USA, 2009, Chelius M. K. , Beresford G. , Horton H. , Quirk M. , Selby G. , Simpson R. T. , Horrocks R. , Moore J. C.

Père Noël cave climatology (air and water temperature, PCO2), hydrology (drip rate, conductivity) and geochemistry of water and calcite deposits (δ18O, δ13C, Mg/Ca and Sr/Ca) where studied to better interpret stable isotopic and trace element variations of speleothems. Results of an automated monitoring station and of manual sampling between 1991 and 1998 have demonstrated the highly seasonal signal of drip rate, its control by water excess and rainfall, and, at a shorter scale to air pressure changes. The modern calcite deposit study suggests a relationship between cave calcite isotopic composition (δ18O and δ13C) and drip rate likely due to variations in degree of isotopic equilibrium during calcite precipitation. δ18O and δ13C of the calcite are therefore, through drip rate, linked to water recharge. Mg/Ca and Sr/Ca ratios of Père Noël cave calcite, depend closely on the residence time of the water, and therefore are also linked to drip rate and therefore to water recharge. This crossed link of δ18O and δ13C as of Mg/Ca and Sr/Ca to water recharge may explain the very similar variations of these four parameters along the longitudinal axis of a Holocene stalagmite, but it may also be the consequence of kinetic effects during calcite precipitation as suggested by similar variations of the four parameters along a single layer of the Holocene stalagmite.


Epikarst hydrology and implications for stalagmite capture of climate changes at Grotta di Ernesto (NE Italy): results from long-term monitoring, 2010, Miorandi Renza, Borsato Andrea, Frisia Silvia, Fairchild Ian J. , Richter Detlev K.

Grotta di Ernesto is a cave site well suited for palaeoclimate studies because it contains annually laminated stalagmites and was monitored from 1995 to the end of 2008 for microclimate, hydrology and hydrochemistry. Long-term monitoring highlighted that cave drips show three different hydrological responses to rainfall and infiltration: (1) fast seasonal drips in the upper part of the cave, which are mostly fed by fractures, (2) slow seasonal drips, located at mid-depth in the cave characterized by mixed feeding and (3) slow drips, mostly located in the deeper gallery, which are fed by seepage flow from bulk porosity with a minor fracture-fed component. The slow drips display daily cycles during spring thaw. Monitoring also indicated that drip waters are only slightly modified by degassing within the soil zone and aquifer and by prior calcite precipitation. Hydrochemical studies show a clear seasonality in calcite saturation index, which results in most cave calcite precipitation occurring during late autumn and winter with similar amounts of precipitated calcite on most stalagmites, regardless of drip rate (discharge) differences. Drip rate, and drip rate variability, therefore, has a minor role in modulating the amount of annual calcite formation. In contrast, drip rate, when associated with moderate reduction in calcite saturation index, clearly influences stalagmite morphology. Increasing drip rate yields a passage from candle-, to cone- to dome-shaped stalagmites. Very high drip rates feed speleothems with flowstone morphology. In summary, monitoring provides information about the karst aquifer and how hydrology influences those physical and chemical characteristics of speleothems which are commonly used as climate proxies.


Hypogean microclimatology and hydrogology of the 800-900 m asl level in the Monte Corchia cave (Tuscany, Italy): Preliminary considerations and implications for paleoclimatological studies, 2011, Ilaria Baneschi, Leonardo Piccini, Eleonora Regattieri, Ilaria Isola, Massimo Guidi, Licia Lotti, Francesco Mantelli, Marco Menichetti, Russell N. Drysdale & Giovanni Zanchetta:

The Monte Corchia Cave is one of the most promising sites for studying the paleoclimate of the Mediterranean basin, but its hydrology and hydrogeochemistry are still poorly known. In this paper, we report some meteoclimatic and hydrochemical data for different parts of the cave. Conductivity and water level data from La Gronda channel show that this system reacts rapidly to external meteoric events, indicating the presence of a conductive epikarst. Data on two different drips indicate that the physicochemical parameters, such as conductivity, pH, δ13CDIC and drip rate depend on the local structural setting and water path length. The data presented show that Galleria delle Stalattiti (the focus of the paleoclimate research) has the most stable conditions in terms of temperature, and the dripwaters show constant pH, electrical conductivity, alkalinity, calcium and magnesium content and δ18O. Drip rate is not affected by rain events and displays long-term trends that require a longer period of monitoring for elucidating their nature. The preliminary data presented here corroborate the hypotheses suggesting Galleria delle Stalattiti as a good example of a “deep” hypogean system of Fairchild et al. (2007).


Oxygen isotopes in calcite grown under cave-analogue conditions, 2011, Day C. C. , Henderson G. M.

Speleothem oxygen isotopes and growth rates are valuable proxies for reconstructing climate history. There is debate, however, about the conditions that allow speleothems to grow in oxygen isotope equilibrium, and about the correct equilibrium fractionation factors. We report results from a series of carbonate growth experiments in karst-analogue conditions in the laboratory. The setup closely mimics natural processes (e.g. precipitation driven by CO2-degassing, low ionic strength solution, thin solution film) but with a tight control on growth conditions (temperature, pCO2, drip rate, calcite saturation index and the composition of the initial solution). Calcite is dissolved in water in a 20,000 ppmV pCO2 environment. This solution is dripped onto glass plates (coated with seed-carbonate) in a lower pCO2 environment (and rapid depletion of the dissolved inorganic carbon reservoir (rapid DIC-depletion). The impact of evaporation can be large so caves with high relative humidity are also preferable for palaeoclimate reconstruction. Even allowing for the maximum offsets that may have been induced by evaporation and rapid DIC-depletion, d18O measured in some of our experiments remain higher than those predicted by Kim and O’Neil (1997). Our new results are well explained by equilibrium at a significantly higher acalcite–water, with a kinetic-isotope effect that favours 16O incorporation as growth rate increases. This scenario agrees with recent studies by Coplen (2007) and Dietzel et al. (2009). Overall, our results suggest that three separate processes cause d18O to deviate from true isotope equilibrium in the cave environment. Two of these drive d18O to higher values (evaporation and rapid DIC-depletion) while one drives d18O to lower values (preferential incorporation of 16O in the solid carbonate at faster growth rates). While evaporation and DIC-depletion can be avoided in some settings, the third may be inescapable in the cave environment and means that any temperature to d18O relationship is an approximation. The controlled conditions of the present experiments also display limitations in the use of the Hendy test to identifying equilibrium growth.


Spatially dense drip hydrological monitoring and infiltration behaviour at the Wellington Caves, South East Australia, 2012, Jex Catherine N. , Mariethoz Gregoire, Baker Andy, Graham Peter, Andersen Martin S. , Acworth Ian, Edwards Nerilee, Azcurra Cecilia

Despite the fact that karst regions are recognised as significant groundwater resources, the nature of groundwater flow paths in the unsaturated zone of such fractured rock is at present poorly understood. Many traditional methods for constraining groundwater flow regimes in karst aquifers are focussed on the faster drainage components and are unable to inform on the smaller fracture or matrix-flow components of the system. Caves however, offer a natural inception point to observe both the long term storage and the preferential movement of water through the unsaturated zone of such fractured carbonate rock by monitoring of drip rates of stalactites, soda straws and seepage from fractures/micro fissures that emerge in the cave ceiling. Here we present the largest spatial survey of automated cave drip rate monitoring published to date with the aim of better understanding both karst drip water hydrogeology and the relationship between drip hydrology and surface climate. By the application of cross correlation functions and multi-dimensional scaling, clustered by k-means technique, we demonstrate the nature of the relationships between drip behaviour and initial surface infiltration and similarity amongst the drip rate time series themselves that may be interpreted in terms of flow regimes and cave chamber morphology and lithology.


Layer-bounding surfaces in stalagmites as keys to better paleoclimatological histories and chronologies, 2013, Railsback L. B. , Akers P. D. , Wang L. , Holdridge G. A. , Riavo Voarintsoa N.

Petrographic recognition of layer-bounding surfaces in stalagmites offers an important tool in constructing paleoclimate records. Previous petrographic efforts have examined thickness of layers (a possible proxy for annual rainfall) and alternation of layers in couplets (a possible indicator of seasonality). Layer-bounding surfaces, in contrast, delimit series of layers and represent periods of non-deposition, either because of exceptionally wet or exceptionally dry conditions.

Two types of layer-bounding surfaces can be recognized according to explicitly defined petrographic criteria. Type E layer-bounding surfaces are surfaces at which layers have been truncated or eroded at the crest of a stalagmite. Keys to their recognition include irregular termination of layers otherwise present on the stalagmite’s flank, dissolutional cavities, and coatings of non-carbonate detrital materials. Type E surfaces are interpreted to represent wet periods during which drip water became so undersaturated as to dissolve pre-existing stalagmite layers, and thus they necessarily represent hiatuses in the stalagmite record. Type L layer-bounding surfaces are surfaces below which layers become thinner upward and/or layers have lesser lateral extent upward, so that the stalagmite’s layer-specific width decreases. They are thus surfaces of lessened deposition and are interpreted to represent drier conditions in which drip rate slowed so much that little deposition occurred. A Type L surface may, but does not necessarily, represent a hiatus in deposition. However, radiometric age data show that Type L surfaces commonly represent significant hiatuses.

These surfaces are significant to paleoclimate research both for their implications regarding climate change (exceptionally wet or dry conditions) and in construction of chronologies in which other data, such as stable isotope ratios, are placed. With regard to climate change, recognition of these surfaces provides paleoclimatological information that can complement or even substitute for geochemical proxies. With regard to chronologies, recognition of layer- bounding surfaces allows correct placement of hiatuses in chronologies and thus correct placement of geochemical data in time series. Attention to changing thickness of annual layers and thus to accumulation rate can also refine a chronology. A chronology constructed with attention to layer-bounding surfaces and to changing layer thickness is much more accurate than a chronology in which hiatuses are not recognized at such surfaces.


Using hydrogeochemical and ecohydrologic responses to understand epikarst process in semi-arid systems, Edwards plateau, Texas, USA, 2013, Schwartz Benjamin F. , Schwinning Susanne, Gerrard Brett, Kukowski Kelly R. , Stinson Chasity L. , Dammeyer Heather C.

The epikarst is a permeable boundary between surface and subsurface environments and can be conceptualized as the vadose critical zone of epigenic karst systems which have not developed under insoluble cover. From a hydrologic perspective, this boundary is often thought of as being permeable in one direction only (down), but connectivity between the flow paths of water through the epikarst and the root systems of woody plants means that water moves both up and down across the epikarst. However, the dynamics of these flows are complex and highly dependent on variability in the spatial structure of the epikarst, vegetation characteristics, as well as temporal variability in precipitation and evaporative demand. Here we summarize insights gained from working at several sites on the Edwards Plateau of Central Texas, combining isotopic, hydrogeochemical, and ecophysiological methodologies. 1) Dense woodland vegetation at sites with thin to absent soils (0-30 cm) is in part supported by water uptake from the epikarst. 2) However, tree transpiration typically becomes water-limited in dry summers, suggesting that the plant-available fraction of stored water in the epikarst depletes quickly, even when sustained cave drip rates indicate that water is still present in the epikarst. 3) Flow paths for water that feeds cave drips become rapidly disconnected from the evaporation zone of the epikarst and out of reach for plant roots. 4) Deep infiltration and recharge does not occur in these systems without heavy or continuous precipitation that exceeds some threshold value. Thresholds are strongly correlated with antecedent potential evapotranspiration and rainfall, suggesting control by the moisture status of the epikarst evapotranspiration zone. The epikarst and unsaturated zone in this region can be conceptualized as a variably saturated system with storage in fractures, matrix porosity, and in shallow perched aquifers, most of which is inaccessible to the root systems of trees, although woody vegetation may control recharge thresholds.


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