bluuebunny/crossref_metadata_2025 huggingface dataset:
Aspects of the Evolution of an Important Geo-Ecosystem in the Lessinian Mountain (Venetian Prealps, Italy)
Authors: Latella Leonardo , Sauro Ugo
Published: February 2016

The Grotta dell’Arena (476 V/VR), located in the Lessinian Mountain, at the elevation of 1512 m a.s.l., is a very important underground karst system. Although it is only 74 m long, several of the geological, geomorphological and environmental features of the High Lessinian underground karst are present in this cave. The Grotta dell’Arena shares some common geological and faunistic characters with other important and well known karst systems. This cave has also one of the highest number of troglobitic species in all Venetian Prealps and some of them possibly originated in the pre-Quaternary. From the geological point of view the cave is the expression of a contact karst, where different limestone types come in contact both stratigraphically and along tectonic structures. The Grotta dell’Arena is located at the stratigraphic contact between the “Calcari del Gruppo di San Vigilio” and the “Rosso Ammonitico” and it is very close to a fault plane putting in vertical contact the two above formations with the “Biancone”, a kind of limestone closely stratified and densely fractured, very sensible to frost weathering. It is interesting to note the presence of a good number of species of Tertiary, or more generally pre-Quaternary, originate in the Grotta dell’Arena. This presence is possibly related to the geology of caves. In this paper the different kinds of underground karst systems in the Grottta dell’Arena and Lessinian Mountain, are analyzed and the relation with the cave fauna distribution are taken in consideration.
What Does the Distribution of Stygobiotic Copepoda (Crustacea) Tell Us About Their Age?
Authors: Culver David C. , Pipan Tanja
Published: February 2016

Geographic distribution of stygobionts is often used to estimate age of a group by assuming vicariant speciation with little or no subsequent dispersal. We investigated the utility of using distributional data for Slovenian stygobiotic copepods by assuming that dispersal is a way to measure age of a species. We list some species of Copepoda that, on the basis of their range and frequency of occupancy within their range, should be older. Body size is not predictor either of range or frequency of occupancy.
A Review of Coalesced, Collapsed-Paleocave Systems and Associated Suprastratal Deformation
Authors: Loucks Robert G
Published: February 2016

Coalesced, collapsed-paleocave systems and associated suprastratal deformation appear to be prominent diagenetic/structural features in carbonate sections at/near composite unconformities. The basic architecture of the system can be divided into two sections. The lower karsted section, where high-density cave formation took place, is preserved as massive breccias commonly displaying a rectilinear pattern in map view. The overlying suprastratal deformation section is characterized by large, circular to linear sag structures containing faults and fractures. Regional distribution of coalesced, collapsed-cave systems commonly appears as large-scale (hundreds to thousands of square kilometers in area), rectilinear patterns with areas of concentrated, coalesced breccias separated by relatively undisturbed host rock. This pattern may reflect development of the paleocave system along fracture swarms. Collapsed-paleocave systems are large, complex features that show broad-scale organization. The complete paleocave system may need seismic data or large, mountain-scale outcrops to define their architecture and distribution.
How Long Does Evolution of the Troglomorphic Form Take? Estimating Divergence Times in Astyanax Mexicanus
Authors: Porter Megan L. , Dittmar Katharina , Pérez-Losada Marcos
Published: February 2016

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).
Age Estimates for Some Subterranean Taxa and Lineages in the Dinaric Karst
Authors: Trontelj Peter , Gorički Špela , Polak Slavko , Verovnik Rudi , Zakšek Valerija , Sket Boris
Published: February 2016

Using a comparative phylogeographic approach and different independent molecular clocks we propose a timescale for the evolution of troglobionts in the Dinaric Karst that is relatively consistent over a wide taxonomic range. Keystone events seem to belong to two age classes. (1) Major splits within holodinaric taxa are from the mid-Miocene. They present the potential upper limit for the age of cave invasions. (2) Regional differentiation, including speciation, which can at least in part be associated with a subterranean phase, took place from early Pliocene to mid-Pleistocene. We suggest two to five million years as the time when most of the analyzed lineages started invading the Dinaric Karst underground.
The Challenge of Estimating the Age of Subterranean Lineages: Examples from Brazil
Authors: Trajano Eleonora
Published: February 2016

The applicability and effectiveness of different kinds of evidence used to estimate the age of lineages – morphological, molecular, phylogenetic, biogeographical, geological – are discussed. Examples from the Brazilian subterranean fauna are presented, using mainly fishes, one of the best studied groups, as a model. Only three taxa including troglobites are object of molecular studies, all in progress. Therefore, molecular clocks cannot be applied yet, and indirect evidence is used. Few phylogenies are available, e.g. for the catfish families Heptapteridae and Trichomycteridae. Theoretically, basal troglobitic clades are older than apical ones, but the possible existence of extinct epigean taxa belonging to such clades hampers the comparison. As well, the limitations of the use degrees of troglomorphism to estimate phylogenetic ages are analyzed with focus on the complexity of the mechanisms underlying morphological differentiation. Paleoclimatic reconstructions based on dating of speleothems from caves in northeastern and southeastern Brazil are available, but limited up to the last 200,000 years, thus useful for relatively recent lineages. Topographic isolation, probable for some fish groups from Central Brazil, is also within the time range of 105 years. Older dated events (in the order of 106 years or more) that may represent vicariant events affecting aquatic lineages with subterranean derivatives are related to the establishment of the modern South American main river basins. In view of the paucity of data useful for estimating the age of Brazilian troglobitic lineages, combined evidence, including morphology, systematics and biogeography, seems to be the best approach at the moment.
The Role of Condensation Corrosion in Thermal Speleogenesis. Study of a Hypogenic Sulfidic cCve in Aix-les-Bains, France
Authors: Audra Philippe , Hoblea Fabien , Bigot Jean-Yves , Nobecort Jean-Claude
Published: February 2016

Condensation-corrosion is an active speleogenetical process in thermal caves where high thermal gradient drives air convection. Wall retreat rates are greater than in meteoric caves. Conversely, evaporation produces depositional processes by replacement of limestone by gypsum and by aerosol decantation leading to the formation of popcorns. The Chevalley Aven belongs to Aix-les-Bains thermal-sulfidic cave system. Condensation occurs at the contact of cool walls of large spheres; conversely, evaporation occurs at the output of the narrow passages where the air sinks down from the upper sphere. A weathered layer and biofilms are present where slow condensation occurs. Corrosion distribution varies according to thermal rock conductivity and causes the sphere to develop upwards, laterally, and divergent. This mor­phodynamic pattern favors the development of stacked spheres, isolated by narrow necks, and arranged in a bush-like pattern. This development is clearly active in the vadose zone above the thermal water table. We propose that some avens above wa­ter table hypogenic caves, like Villa Luz (Mexico), may be of condensation-corrosion origin instead of phreatic. Future de­velopment will collect physical and chemical data to calculate the condensation-corrosion budget and assess its role in cave development
Rainwater Percolation Dynamics Assessment through the Vadose Karst Zone on the Basis of Discharge Measurements
Authors: Kogovšek Janja
Published: February 2016

Researches based on seasonal and later continuous measurements of precipitation on the surface and discharges of typical trickles in Postojnska Jama, 100 m below the surface, showed the dynamics of percolation in a period of a hydrological year. They registered summer periods lasting several months when all the rainfall, even more abundant, is stored in a vadose zone. After a longer dry period the first discharge reactions of trickles to rainfall strongly differ while there is no substantial difference in a wet period. The water outflow in decreasing parts of water pulses essentially differs among various trickles and we recognised the types of trickles feeding karst aquifers even during low water level or low discahrges of karst springs.
A Steady State Hydraulic Model of a Karst Aquifer
Authors: Turk Janez
Published: February 2016

It is known, that 90 % or even more of underground water flows through large conduits. Restrictions and siphons represent only small percentage of karstic aquifer. But because of them, conduits, which transmit water, are only partly accessible. Difficult access is a reason why many water transmissions have not been explored yet. Because of this, geometry and length of all underground conduits is not known, it can be only predicted. In such a case processes of water flow in karstic conditions are more easily predictable by modeling. Basic physical models are usually used. They are based on the conduit permeability of karst water. We assume conduits with different dimensions, smaller usually presenting areas of full pipe flow (under pressure) and larger open channel flow. We were interested in the hydraulic conditions, when does the change from open channel to full pipe flow occur and when does underground flow from main conduit divide into two neighbouring conduits. The response of a karst aquifer to a flood pulse was not studied in our model, but we observed its behaviour during a constant increase of recharge into the karstic underground.
Karst and World Heritage Status
Authors: Hamilton-Smith Elery
Published: February 2016

Approximately 50 karst sites are now inscribed on the World Heritage Register, but many of these are inscribed on the basis of their non-karst values. Karst systems, of course, have a very wide range of values in themselves, including their remarkable biodiversity and their cultural significance, sometimes spanning many thousands of years. Today, the World Heritage Committee and UNESCO have asked that consideration be given to determining both a strategy for the nomination of new sites and a basis for priority setting in the selection of potential sites. This paper reviews current trends and emerging new patterns in World Heritage selection, assessment and management, then summarises the values of current karst WHAs in the European region.
Physics and Chemistry of Dissolution on Subaerialy Exposed Soluble Rocks by Flowing Water Films
Authors: Dreybrodt Wolfgang , Kaufmann Georg
Published: February 2016

The basic process active in the formation of subaerial features on karst rocks is chemical dissolution of limestone or gypsum by water films flowing on the rock surface. The dissolution rates of limestone and gypsum into thin films of water in laminar flow are given by F = α(ceq-c), where (ceq-c) is the difference of the actual concentration c in the water film and the equilibrium concentration ceq with respect to the corresponding mineral. Whereas for gypsum α is determined by molecular diffusion the situation is more complex for limestone. Experiments are presented, which show that for high undersaturation, c<0.3ceq, the rate law is F = α( 0.3ceq-c) ,and α becomes higher by about a factor of ten than for the rates at c>0.3ceq. These rate laws are used to calculate denudation rates on bare rock surfaces exposed to rainfall with differing intensity. The estimations are in reasonable agreement to field data. Starting from the experiments on the formation of Rillenkarren on gypsum performed by Glew and Ford (1980), we suggest a new relation between their length from the crest to the “Ausgleichsfläche” and the inclination of the rock surface. This is also applied to field data of Rillenkarren on limestone provided by J. Lundberg and A. Gines. In view of the many parameters influencing the formation of Rillenkarren these correlations can be considered as satisfactory.
Fractal Analysis of the Distribution of Cave Lengths in Slovenia
Authors: Verbovšek Timotej
Published: February 2016

The lengths of the Slovenian caves follow the power-law distribution through several orders of magnitude, which implies that the caves can be considered as natural fractal objects. Fractal dimensions obtained from distribution of all caves are about 1.07, and vary within different tectonic and hydrogeological units. Some deviations from the ideal best fit line in log-log plots (i.e. lower and upper cut-off limits) can be explained by underestimation, as many very short caves are not registered. The study of tectonic and hydrogeological setting indicates that the greatest dimensions occur in the rocks with karstic-fracture and fracture porosity and the lowest in low-permeability rocks. Proximity to major tectonic structures shows a detectable effect on the cave length distribution, and the influence is greatest for the caves closer to the faults and thrust fronts. Dimensions are lower than those of fracture networks and faults, which can be most probably explained by flow channeling along the fracture networks, which causes the decrease of fractal dimension. The physical causes of power law scaling and variations in fractal dimensions (power law exponents) are still poorly understood, but the behaviour of fracture networks is believed to be caused by a scale-independent fractal fragmentation of the blocks, and during the process of forming the caves inherit some fractal geometrical properties of the networks.
Cave Turbidites
Authors: Osborne R. Armstrong L.
Published: February 2016

Turbidites are uncommon in caves, but are more common as palaeokarst deposits. Marine carbonate turbidites, called cay­manites, are the most common cave and palaeokarst turbidites, but marine non-carbonate turbidites, freshwater carbonate turbidites and freshwater non-carbonate turbidites are also de­posited in caves and preserved in palaeokarst sequences. One of the most complex sequences of cave turbidites occurs in the Wellington Caves Phosphate Mine in Australia. Cave turbidites form in ponded water in caves and may be triggered by floods and highintensity rain events. While caymanites are most likely to form during marine transgressions, they can be emplaced by tsunami. Freshwater cave turbidites are most likely to form in flooded hypogene caves located in the seasonally wet tropics and in areas withirregular highintensity rainfall events.
Broken Speleothems as Indicators of Tectonic Movements
Authors: Šebela Stanka
Published: February 2016

In karst caves broken and non-ideal speleothems are very wide­spread. Mostly they develop because of the instability of the ground due to its composition (loose sand or loam). The pres­ence of recent cryoturbation in some caves in higher altitudes suggests that some ancient breaks of the speleotheme can be caused by ice in the cave. And we also have some good proofs for recent and past tectonic activity in karst caves. In many cases it is very difficult to determine the real reason for broken speleothems, because several reasons could be interacting. In Postojna Cave some examples related to tectonics were stud­ied.
The Flow Rate of Fonte Pliniana (Como, Italy): Two Thousands Years of Data
Authors: Cigna Arrigo A.
Published: February 2016

Since the Roman time the Fonte Pliniana attracted the inter­est of many visitors. Here some observations recorded in nearly 2000 years are reported. The measurements made during the XX century allowed also the evaluation of some hydraulic pa­rameters of the spring system.
Groundwater Flow in Crystalline Carbonates (Jeseniky Mts., Chech Rep.): Using Stream Thermometry and Groundwater Balance for Catchment Delineation
Authors: Kukačka Jan , Altová Viola , Bruthans Jiří , Zeman Ondřej
Published: February 2016

Strips of metamorphosed carbonate rocks in a contact-karst area in the Jeseniky Mts, CzechRepublic, act as aquifers, drain­ing broad areas of crystalline rocks, mostly phyllites. Significant groundwater resources that are partly used as a water supply are in carbonate rocks. Detailed temperature and conductivity measurements coupled withdischarge measurements along all streams in the area demonstrate a relatively quick method to lo­cate virtually all important groundwater outflows from carbon­ates. Discharge measurements of streams crossing carbonate strips enabled us to locate and quantify the capacity of ponors and losing parts of streams in various water stages. Thanks to a detailed knowledge of losing and gaining parts of streams, we were able to select appropriate profiles to separate catchments withdiffering hydrologic balances (balanced, gaining, losing). Flow directions in carbonates and recharge and discharge ar­eas were delineated by comparing the specific discharges of individual catchments. Resulting flow directions agree withtracer tests in the area. Our outlined approachcan be used in many other areas to locate hidden inflows into streams and to estimate flow between individual small catchments, and it may partly compensate for tracer tests as it allows flow directions to be estimated from hydrological balance and rock geometry.
Investigations Regarding Bear Cave Massif (Lower Silesia) Long-Term Stability
Authors: Mąkolski Krzysztof , Cacoń Stefan , Jamroz Olgierd , Košták Blahoslav , Kaczałek Mirosław
Published: February 2016

Bear Cave under Mt ¦nie¿nik is located near the Lower Sile­sian Village of Kletno in a wider tectonic fault zone of Sudeten, Klodzko Valley, South Poland. Stability requirements along the visitor’s path in the cave called for permanent checks of pos­sible rock movements in the massif, while mining operations in the neighbouring marble quarry represented major threat to cave stability. Precise levelling network for vertical movements in the cave and its vicinity was established about 20 years ago. Outside the cave in the Kle¶nica River valley levelling traverses were crossing tectonic faults. Periodical measurements have been repeated since 1984. In the cave two fault zones of major risk have been checked also with TM-71 crack gauges and re­cords have been taken with a month frequency. These two were the tectonic crack zones of the Water Corridor and the main fault structure of the cave found in the Cascade Alley. Fourteen years ago after finding that quarry blasts induced increased movements in the cave, quarry operations were stopped. Re­cently, gradual subsidence of some levelling bench-marks was observed, as well as some periods of increased micro-displace­ments on the tectonic crack zones. Such observations are dis­cussed.
Do turloughs occur in Slovenia?
Authors: Sheehy Skeefington Micheline , Scott Nick E.
Published: February 2016

Micheline Shehy Skeffington & Nick. E. Scott: Do turloughs occur in Slovenia? Turloughs are karst basins that fill seasonally with mostly groundwater and drain, usually in summer, to reveal a sedge or grassland community. They are often described as being virtually unique to Ireland. The much larger seasonal poljes of the Slovenian karst are considered different to turloughs. However, a series of small temporary karst lakes in the Slove­nian Pivka valley seem remarkably similar to Irish turloughs. Like turloughs, they fill and empty largely through estavelles connecting to underground water systems, which rise and fall with high seasonal rainfall. The Slovenian sites, however, support less wetland communities than Irish turloughs, prob­ably due to drier summer conditions. The plant communities of both systems occur in zones around the basin, related to flood duration. Relevés taken at five Slovenian sites revealed that Petelinjsko jezero, which floods longest each year, is the most similar to turloughs, with, in the lower basin, Eleocharis palustris, potentilla reptans and the unusual form of Ranuculus repens commonly found in Irish turloughs. The difference in climate and terrain means that the Slovenian sites are managed for hay or silage, while the Irish turloughs are under pasture. However, for both, regular flooding precludes much agricul­tural improvement, so that they are now refuges for flora and fauna. A revised definition for turloughs is proposed and a case made for these Slovenian wetland systems to be recognised as turloughs and for the EU Habitats Directive to be amended to include poljes and other similar temporary karst wetland sys­tems as well as turloughs.
Small-scale Terraces and Isolated Rimstone Pools on Stalagmites in Caves Exhibit Striking Similarity to Large-scale Terrace Landscapes at Hot Springs
Authors: Dreybrodt Wolfgang , Gabrovšek Franci
Published: February 2016

We report on sinter terrace forms on the centimetre scale observed on the top and at the base of a stalagmite in Škocjanske jame (Škocjan caves). These exhibit connected rimstone dams, forming a net-like pattern with active water pools inside. The form is similar to those seen at the large travertine terraces, which form by precipitation of calcite from spring waters highly supersaturated with respect to calcite. In contrast to these patterns we have also found isolated sinter basins with dimensions of a few centimeter on stalagmite-like structures in the cave Dimnice, Slovenia. Similar basins a few meters wide are a tourist attraction in Pamukkale, Denizli, Turkey. The observed features have grown from supersaturated solutions of calcium carbonate in laminar flow. Large-scale landscapes originate under conditions of turbulent flow. Some ideas are presented why, in spite of the clear difference in flow, the shapes are similar on all scales.
Doline Fills - Case Study of the Faverghera Plateau (Venetian Pre-Alps, Italy)
Authors: Sauro Ugo , Francese Roberto , Ferrarese Francesco , Miola Antonella , Mozzi Paolo , Rondo Gualtiero Quario , Trombino Luca , Valentini Gianna
Published: February 2016

The sedimentary fills of two dolines in the Faverghera plateau in the Venetian Pre-Alps, south of Belluno, have been investigated. This small plateau is a sub-horizontal surface about 0.5 km2 wide, located on the northeastern slope of Mt. Faverghera (1640 m a.s.l.) hosting nearly 40 karst dolines partially filled by periglacial slope deposits. Topographic survey, electric resistivity tomography (ERT), soil and pollen analyses have been carried on. The structure of the dolines and the characters of the filling deposits indicate that the evolution of these forms has been controlled by the alternation of different climatic and environmental conditions during the Pleistocene. The results indicate that the dolines are “filters” for the sediments, more than good traps, archiving only some of the climatic and environmental changes.
Distribution and Character of Karst in the Lao PDR
Authors: Kiernan Kevin
Published: February 2016

The extensive karst areas of the Lao PDR are poorly documented but are known to include extensive limestone mountain plateaus; isolated ridges including towerkarst; hillslopes that are locally underlain by limestone; and alluvium-covered limestone plains. Palaeokarst phenomena attest to a very long history of karstification while sediments in some caves offer insight into environmental change during the Quaternary. Limited financial and technical resources, political factors and the dangers posed by massive volumes of unexploded ordnance that remain after decades of war are major impediments to karst area documentation, analysis, planning and management. Assessment of karst extent based on aerial photographs and other remote sensing techniques is complicated by very extensive pseudokarst formed due to bombardment during past military conflicts, including hundreds of thousands of closed depressions formed in both carbonate and non-carbonate rocks. Notwithstanding such practical difficulties, the extent and importance of the karst is such that improved inventory at the national, provincial and local levels is required if satisfactory environmental management and sustainable social and economic development are to be achieved.
Small Terrestrial Mammals (Soricomorpha, Chiroptera, Rodentia) from the Early Holocene lLyers of Mala Triglavca (SW Slovenia)
Authors: Toškan Borut
Published: February 2016

At least 132 specimens belonging to no less than 21 species of small terrestrial mammals from the Boreal were identified within the finds from the Early Holocene sediments from Mala Triglavca (the Kras Plateau, SW Slovenia), namely Crocidura suaveolens, Sorex alpinus / araneus, S. minutus, Talpa cf. europaea, Barbastella barbastellus, Sciurus vulgaris, Cricetulus migratorius, Arvicola terrestris, Microtus agrestis / arvalis, M. subterraneus / liectensteini, Chionomys nivalis, Myodes glareolus, Dinaromys bogdanovi, Glis glis, Muscardinus avellanarius and Apodemus flavicollis / sylvaticus / agrarius / uralensis. This small mammal assemblage indicates that their habitat was presumably a mosaic of a mixed, predominantly deciduous forest, dotted with small meadows and some rocky substrate. A comparison of allochronous microfaunas from the Kras Plateau indicated a rapid faunistic change in the last 5,000 years.
Hydrogeochemistry of Coastal Carbonate Aquifer in Lucija–Portorož (Gulf of Trieste, Northern Adriatic Sea, Slovenia)
Authors: Brenčič Mihael
Published: February 2016

The 801 m deep artesian borehole Lu-1 in Lucija near Portorož (SW Slovenia) was drilled in 1994 on the coast. The borehole is constructed in flysch in the upper 257 m and continues in limestone below that depth. The groundwater has a very distinct chemistry. High concentrations of iron (10.4 mg/l), sulphide (15 mg/l), and chloride (6700 mg/l) are representative showing that mixing of seawater (31%) and groundwater (69%) under highly reducing conditions is present in the confined carbonate aquifer. Groundwater flow is extensive and deep, fed by higher elevation precipitation to the northeast.
Ancient Greek Hydromyths About the Submarine Transport of Terrestrial Fresh Water Through Seabeds Offshore of Karstic Regions
Authors: Clendenon Cindy
Published: February 2016

This study examined the relationship between ancient Greek texts and the physical possibility of focused, distal flow of terrestrial fresh water through the seabed, particularly offshore of karstic coasts. The four ancient texts which were analyzed describe powerful discharges from submarine springs in the eastern Black Sea; the local transport of groundwater through the bed of Turkey’s Bay of Miletus; alleged subterranean–submarine connections between coastal western Turkey and the Greek northeast Peloponnese; and alleged connections between the coastal western Peloponnese and southeastern coastal Sicily. The plausibility or implausibility of these legends was assessed in the context of modern reports indicating that seabed pathways can transport continental fresh water up to 60 km offshore. Other reports identify fresh water in the seabed as far as 160 km offshore, presumably due to marine-induced forces. These documented cases validated ancient claims of nearshore groundwater transport and legitimized transoceanic claims as mythologized extrapolations of local karstic hydrogeology. As submarine fresh groundwater becomes increasingly important in understanding material transport and in identifying potentially exploitable coastal water supplies, ancient stories from past civilizations may give clues to offshore sites meriting further exploration.
Spatial and temporal hydrochemical variations of the spring-fed travertine-depositing stream in the Huanglong Ravine, Sichuan, SW China
Authors: Wang Haijing , Liu Zaihua , Zhang Jinliu , Sun Hailong , An Dejun , Fu Ruxian , Wang Xiaoping
Published: February 2016

Automatic hydrochemical logging and in situ titration com­bined withlaboratory analysis were used to understand the spatial and temporal hydrochemical variations of the spring-fed, travertine-depositing stream in celebrated Huanglong Ravine, Sichuan, SW China. This is essential for protection of the Huanglong World Natural Heritage travertine land­scape. It was found that the deposition of travertine was due to very strong CO2 degassing from the water, leading to de­crease in pCO2 and specific conductivity (SpC), and increase in pH and SIc downstream from the Spring. However, regular downstream hydrochemical evolution was interrupted by di­lution withsnow-melt water and by renewed CO2 from some downstream springs. The chemistry of Huanglong Spring itself was stable at a diurnal scale thoughit was altered by the great Wenchuan earthquake of May 12 2008. However, in spring-fed pools downstream, pCO2 and SpC were lower, and pH and SIc were higher in daytime than at night, whichindicates that the deposition of travertine was faster during the daylight hours. This was due to the combined effects of higher water tempera­tures and higher aquatic algae photosynthesis. In addition, it was found that the phosphate concentration in the stream in­creased remarkably downstream in the tourist midseason, in­dicating water pollution by tourism activities. The increase of phosphate (an inhibitor of calcite precipitation) may be one of the reasons for the decrease in travertine deposition rates and accelerated propagation of discoloration by diatoms during the past decades, whichneeds to be given more comprehensive study and tackled in future for the protection of these world famous travertine deposits.
Oxygen Isotopes in Different Recession Subregimes of Karst Springs in the Brezovské Karpaty Mts. (Slovakia)
Authors: Malík Peter , Michalko Juraj
Published: February 2016

Karst spring hydrograph separation method based on quick iterative solution of several simple exponential and linear equations, was developed for linking small datasets of sam­ples to various hydrologic situations. The method is based on a presumption, that a spring’s discharge depends on the level of aquifer saturation by groundwater, and that the same dis­charge reflects the same groundwater saturation (piezometric level) in the aquifer. Every spring can be described by unique sets of constant starting discharges, Q0 values, recession coef­ficients α (laminar flow components in exponential equations), and β (turbulent flow components in linear equations). Eachsubregime can be detected by recession curve analyses of the complete spring’s discharge time series. In this hydrographseparation, every measured discharge value, Qt, is then deter­mined by a representative time, t; i.e., theoretical elapsed time t from the total maximum discharge value Qmax. The aim of the iteration process is to obtain this representative time t for eachdischarge. The individual flow components are calculated us­ing the same t value. These variances in subregime discharges in a certain moment can be linked to the components analysed in the same moment, in order to obtain the end members of the theoretical mixture. This technique was developed and ap­plied on the discharge time series of the four karstic springs in the Brezovské Karpaty Mts. (Slovakia), built mainly by karsti­fied Middle and Upper Triassic dolomites and limestones. Groundwater of individual springs were characterised by δ18O (SMOW) and groundwater temperature values and end mem­bers of two laminar and one turbulent subregimes were calcu­lated. Results were based on sparsely populated datasets and manual discharge records, but represent a perspective method for future development and interpretations on limited dataset results.
Dynamic climatologic processes of barometric cave systems using the example of Jewel Cave and Wind Cave in South Dakota, USA
Authors: Pflitsch Andreas , Wiles Mike , Horrocks Rodney , Piasecki Jacek , Ringeis Julia
Published: February 2016

Jewel and Wind Cave are two big barometric cave systems in SouthDakota, USA. The entrances of Jewel and Wind Cave are roughly 50 km apart, and until now it is unknown whether their entrances belong to two separate caves or to one muchlarger cave system. One possibility for testing these two competing hypotheses is to measure and analyse the climatic conditions in the vicinity of these entrances and within the caves in detail. In this context, the thermal conditions and air currents are crucial. These in turn can be characterised by the spatial and temporal patterns of the dynamics of air entering and leaving throughthe respective entrances; even thoughthese dynamics are coupled to atmospheric pressure fluctuations outside the caves, they differ for different cave systems and provide a “fingerprint” that has implications for the size and structure of individual cave systems. To give an example, Jewel and Wind Cave as the second and fourth-largest cave systems on earthshow some similarities, but many more noticeable differences regarding their climatological behaviour, despite their close proximity to eachother. The last big measurement campaigns on the climatic systems of the two barometric caves were carried out by Herb and Jan Conn in the 1960s, (Conn 1966). Despite their elementary work, the technical possibilities were very limited in those days. The self-constructed mechanical measurement equipment could only be used for basic measurements. Herb Conn was still able to identify the basic mechanism very clearly. He also carried out a number of different calculations on barometric air flow that remain important up to the present day. During the last 40 years, rapid electronic development has enabled us to use instruments that are far more precise and sensitive. The use of ultrasonic anemometers and dataloggers enables us to take more exact long term measurements. An extensive measurement programme was started in 2001 to fulfil several researchaims, and we are now in a position to decipher the different fingerprints of the caves muchmore reliably.
The role and importance of cave microclimate in the sustainable use and management of show caves
Authors: De Freitas Chris R.
Published: February 2016

Cave microclimate is important in the study of cave flora and fauna, certain karst processes underground and hydrogeologic aspects of speleothems; thus an understanding of microclimat­ic processes is especially important in the management of show caves. Here, examples are drawn from researchon New Zea­land caves and examined in the context of sustainable cave use management practices. The work considers that the cave man­ager is concerned, firstly, withdefining the desired or optimal level or range of environmental conditions that should prevail and, secondly, withmaintaining them. To do this requires an appropriate and reliable monitoring system. It involves select­ing key indicators to be monitored and setting target standards. Selection of an appropriate monitoring system, however, re­lies on having a good understanding of the climate processes operating, essentially how they work and how they might be appropriately managed. Unlike microclimates in the atmo­sphere-land boundary layer, whichare characterized by verti­cal exchanges, processes determining climate in all but nearly closed caves are dominated by advection of heat and moisture. It is this process that may give rise to distinct spatial and tem­poral patterns of climates in caves. Thermoadynamic aspects of external air-cave air interaction are assessed to explain spatial as well as short term and seasonal variations of thermal and moisture states of the cave atmosphere. The relevance of all this to cave management is discussed. It is argued that cave man­agement is not simply a matter of determining usage levels or carrying capacity of caves; rather, it involves determining en­vironmental management techniques that are appropriate to a particular cave condition or environmental state that should prevail.
Shore grykes along the western Istrian coast
Authors: Furlani Stefano , Chersicla Davide , Bressan Guido , Biolchi Sara , Cucchi Franco
Published: February 2016

We provided new data on topography, morphology and physical/chemical parameters (pH, T, NO2-, Ca2+, PO43-, NaCl) collected in several shore grykes along the Northwestern Istrian coast, between Savudrija and Zambratija. Six transects, eachcontaining four to five pools, have been surveyed. Three morphological zones have been identified along the selected profiles. Morphological features of the shore grykes along the western Istrian coast are, in fact, closely related to the local tide. High-level pools are affected by karstic processes, and the surface is usually smooth. At their bottom, terrigenous deposits, mainly terra rossa, occur. Seaward, bioerosion prevails and at the bottom of the grykes, sand and rounded pebbles have been found. Chemical/physical parameters suggest that grykes located at lower altitudes are affected by seawater factors, while pools located at increasing altitudes are affected mainly by rainfall and consequentially freshwater or saltwater remaining from rainfalls or storm events. Shore gryke genesis is strongly controlled by geological weakness, along whichthey develop. Their origin is in fact due to local tectonics, while their development is related to the active vertical tectonic subsidence of the study area. Pools located at higher altitudes are mainly affected by solution karst processes, but due to the tectonic downdrop of the area, when the grykes come in contact withsea, they are gradually shaped by marine processes.
The study of karstic aquifers by geodetic measurements in Bus de la Genziana station – Cansiglio plateau (Northeastern Italy)
Authors: Grillo Barbara , Braitenberg Carla , Devoti Roberto , Nagy Ildikò
Published: February 2016

We propose an interdisciplinary study of karstic aquifers using tiltmeters and GPS observations. The study region is located in northeastern Italy, in the seismic area of the Cansiglio Plateau. The Zöllner type Marussi tiltmeters are installed in a natural cavity (Bus de la Genziana) that is part of an interesting karstic area of particular hydrogeologic importance. The Livenza river forms from a number of springs at the foothills of the karstic massif and flows throughthe Friuli-Veneto plain into the Adriatic Sea. Comparing the tiltmeter signal recorded at the Genziana station withthe local pluviometrical series and the hydrometric series of the Livenza river, a clear correlation is recognized. Moreover, the data of a permanent GPS station located on the southern slopes of the Cansiglio Massif (CANV) show also a clear correspondence withthe water runoff. Here we present the hydrologic induced deformations as observed by tiltmeter and GPS. After heavy rain events we record rapid deformations bothby tiltmeters and GPS corresponding to the rainfall duration. In the following days a slow geodetic motion recovers the accumulated deformation witha distinctive pattern bothin tilt and GPS data, whichcorrelates withthe runoff of the karstic aquifer. The purpose of this researchis to open a new multidisciplinary frontier between geodetic and karstic systems studies to improve the knowledge of the underground fluid flow circulation in karstic areas. Furthermore a better characterization of the hydrologic effects on GPS and tilt observations will have the benefit that these signals can be corrected when the focus of the study is to recover the tectonic deformation.
Potential impact of a proposed railway tunnel on the karst environment: The example of Rosandra valley, Classical Karst region, Italy-Slovenia
Authors: Zini Luca , Visintin Luca , Cucchi Franco , Boschin Walter
Published: February 2016

Val Rosandra is a unique geomorphological environment located on the western side of the Classical Karst Plateau (NE Italy). This deep limestone gorge is crossed by a stream that is fed by a large basin located in Slovenia. Val Rosandra is the only example of a karst river valley withsurface hydrography in the Classical Karst Plateau. The torrent that crosses it digs a deep gully into the rock, richin rapids, swirl holes, small waterfalls, enclosed meanders and basins; here, the first seepage phenomena occur, and part of the water feeds the underground aquifer.Val Rosandra is characterised by a complex structural situation. The NE slope culminates in the structure of Mt. Stena, a limestone tectonic wedge between two faults, firmly rooted in the karst platform. Bothits external morphology and its caves are influenced by the structure, i.e. by the attitude of bedding planes, fault planes and master joints. Mt. Stena, in particular, hosts a comprehensive net of articulated and diversely shaped caves, basically organised on several levels. This network stretches over a total of 9,000 metres, bearing testimony to ancient geological and hydrogeological origins.The deepest areas of the system reacha suspended aquifer that is probably sustained by an overthrust and placed about 100 meters above the underground aquifer of the Rosandra torrent.A series of feasibility studies on the Trieste-Divača high-speed railway link concentrated on the potential interaction between the project and karst features. In line withthe project requirements, risk of voids intersection and water contamination were analyzed as Mt. Stena’s suspended aquifer partially feeds the Rosandra torrent, whichflows in a protected natural area. We therefore suggest that further investigations ought to be performed to integrate the existing knowledge on karst and on the hydrogeological aspects of the massif.
Distribution of authigenic and allogenic fractions in recent lake sediment: Isotopic and chemical compositions
Authors: Barešić Jadranka , Horvatinčić Nada , Vreča Polona , Sironić Andreja
Published: February 2016

Recent sediments in Lake Kozjak, in the Plitvice Lakes National Park, Croatia, were used to study the impact of the material delivered to the lake sediment via Rječica Brook. Sediment cores, top 40 cm, were taken near the mouth of the Rječica Brook at three locations in the lake at different distances from the shore, water depth 2-9 m and analyzed using different isotopic and chemical methods. Sediment depth profiles of the following parameters were obtained: organic and carbonate fraction, C/N analyses of organic fraction, 14C activity (a14C) and d13C values of carbonate (d13Ccarb) and organic fraction (d13Corg) and d15N of total nitrogen. The results were compared with sediment core collected in the middle of Lake Kozjak, water depth 21 m. Distribution of organic matter, C/N values, d13Corg and d13Ccarb in sediment profiles showed strong influence of terrestrial organic and carbonate fraction run-off via Rječica Brook which decreased rapidly in the direction of the open lake. The sedimentation rate as well as the ratio of allogenic and authigenic fraction in sediments was estimated. Lower d13Corg values in surface sediments might be a consequence of the increase in algal productivity but might also be a contribution of fossil fuel combustion. The anthropogenicaly induced 14C in the atmosphere in 1963/64 is visible though shadowed in sediments.
A Mysterious Karst: the “Chocolate Hills” of Bohol (Philippines)
Authors: Salomon Jean Noel
Published: February 2016

A public showcase by the Philippine tourism authorities, and rightly so, are the “Chocolate Hills” of Bohol (Philippines), the strangest karst landform known. These numerous residual relief forms are so perfectly symmetrical that, in order to explain their existence, natural explanations are systematically sidelined by legends, myths and many so-called “scientific” explanations. The object of many television broadcasts related to travel, these karst hills are a particularly original example of mogotes tropical karst; their almost “perfect” aspect had intrigued those who have studied their formation and have given birth to many hypotheses. The genesis of the “Chocolate Hills” is due to the emergence of the Pliocene limestone coralline platform, then to its karstification in a particularly homogeneous tropical climate conditions: rainfall, temperature, wind, pedologic and vegetable covers. In other aspects, their good overall porosity explains their mass impregnation by the runoffs as well as the appearance of important aquifers, exploited for the development of irrigated rice fields. Karst models are present, notably the caves and underground networks of which very few have been explored. Finally this original context (insularity, virgin tropical forest undisturbed for a long time) permitted the sustainability of a particularly original endemic fauna including the famous Bohol tarsier. In June 1998 the “Chocolate Hills” were declared the National Geologic Monument and this national park definitely merits a visit.