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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 displacement is 1. the process of replacing one fluid in a porous medium by another [16]. 2. a change in position of a material point. see also miscible displacement.?

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.
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Featured articles from other Geoscience Journals
Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
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Your search for microclimate (Keyword) returned 50 results for the whole karstbase:
Showing 46 to 50 of 50
In situ nitrogen fixation by cyanobacteria at the Andragulla Cave, Spain, 2011, Asencio A. D. , Aboal M.

Andragulla Cave is 2 m high, 6 m wide, and 2 m long (deep). Its lack of depth means that it is not isolated from external influences, and the microclimate is very similar to that experienced externally. The common stress factors on the growth of cyanobacterial communities on walls inside of Andragulla Cave include excess light, dryness, lack of nutrients, and cold temperatures. Nitrogen fixation, photon flux, relative humidity, and temperature in Andragulla Cave were measured hourly over 24 hours in winter. Nitrogen fixation by the reddish-brown mat formed by both cyanobacteria Scytonema mirabile and Gloeocapsa sanguinea in cave-like environments was measured in situ for the first time by acetylene reduction. The mat-specific rates (1.6 to 7.5 nmol C2H4
m22 s21) were lower compared to published values from laboratory measurements of rehydrated samples from different environments. Daytime fixation was slightly higher than nighttime fixation, where nitrogen fixation by Gloeocapsa sanguinea played an important role. The most influential parameters for environmental nitrogen fixation in
Andragulla Cave were photon flux for daytime fixation, temperature for nighttime fixation, and relative humidity for both. Nitrogen fixation by cyanobacteria may be significant in these N-poor ecosystems.

Variances in airflows during different ventilation modes in a dynamic U-shaped cave, 2013, Faimon J. , Lang M.

Airflow dynamics were studied in Císařská Cave (Moravian Karst, Czech Republic) under different seasonal conditions. The dependence of airflows on the difference between external and cave temperatures is nonlinear and roughly obeys the Darcy-Weisbach equation. The upward airflows were found to be systematically higher than the downward airflows under comparable driving forces. The principle reason is nonlinearity between air temperature and air density. U-shaped cave geometry magnifies this effect by feedback between external temperature and airflow driving forces. Whereas this feedback is positive during the upward airflow ventilation mode, it is negative during the downward airflow mode. To discuss the behavior in detail, a simplified model based on balancing the masses of two equivalent air columns of different temperatures and densities is proposed. The results contribute to a better understanding of cave microclimate evolution, cave CO2 dynamics, and speleothem growth.

Microhabitat influences the occurrence of airborne fungi in copper mine in Poland, 2014, Pusz W. , Kita W. , Weber R.

From January to April 2012 we studied the occurrence of air-borne fungi in the Lubin mining site, property of KGHM Polska Miedz´ SA. The research was conducted in three copper-mining shafts: Bolesław, Lubin Zachodni (Lubin West shaft), and Lubin Gło´wny (Lubin Main shaft) at about 610 to 850 meters below ground level. Air samples were collected between 6 and 9 a.m. using the impact method (Air Ideal 3P Sampler) onto Potato Dextrose Agar. The volume of air sampled for each agar plate was 50 liters. We found twenty-seven fungal species, the most numerous being Penicillium notatum, P. urticae, and Aspergillus flavus. As the application of log-linear and correspondence analyses have shown, the population of fungi varied considerably among the copper mine shafts or shaft parts. P. notatum and P. urticae were found to be the best adapted to grow in copper-mine conditions. The significant interaction among the shafts and the sample collection sites suggests a substantial microclimate influence on the population-size variations of studied fungal species in each shaft. The fungal-spore concentration in the majority of the shafts of this copper mine does not present a health risk to the mine workers. But it is enhanced in some portions of the mine, so it may constitute a health hazard locally.

The role of condensation in the evolution of dissolutional forms in gypsum caves: Study case in the karst of Sorbas (SE Spain), 2014, Gazquez F. , Calaforra J. M. , Forti P. , Waele J. D. , Sanna L.

The karst of Sorbas (SE Spain) is one of the most important gypsum areas worldwide. Its underground karst network comprises over 100 km of cave passages. Rounded smooth forms, condensation cupola and pendant-like features appear on the ceiling of the shallower passages as a result of gypsum dissolution by condensation water. Meanwhile, gypsum speleothems formed by capillarity, evaporation and aerosol deposition such as coralloids, gypsum crusts and rims are frequently observed closer to the passages floors. The role of condensation-dissolution mechanisms in the evolution of geomorphological features observed in the upper cave levels has been studied by means of long-term Micro-Erosion Meter (MEM) measurements, direct collection and analysis of condensation waters, and micrometeorological monitoring. Monitoring of erosion at different heights on gypsum walls of the Cueva del Agua reveals that the gypsum surface retreated up to 0.033 mm yr- 1 in MEM stations located in the higher parts of the cave walls. The surface retreat was negligible at the lowest sites, suggesting higher dissolution rates close to the cave ceiling, where warmer and moister air flows. Monitoring of microclimatic parameters and direct measurements of condensation water were performed in the Covadura Cave system in order to estimate seasonal patterns of condensation. Direct measurements of condensation water dripping from a metal plate placed in the central part of the El Bosque Gallery of Covadura Cave indicate that condensation takes place mainly between July and November in coincidence with rainless periods. The estimated gypsum surface lowering due to this condensation water is 0.0026 mm yr- 1. Microclimatic monitoring in the same area shows differences in air temperature and humidity of the lower parts of the galleries (colder and drier) with respect to the cave ceiling (warmer and wetter). This thermal sedimentation controls the intensity of the condensation-evaporation mechanisms at different heights in the cave.

Airborne microorganisms in Lascaux Cave (France), 2014,

Lascaux Cave in France contains valuable Palaeolithic paintings. The importance of the paintings, one of the finest examples of European rock art paintings, was recognized shortly after their discovery in 1940. In the 60’s of the past century the cave received a huge number of visitors and suffered a microbial crisis due to the impact of massive tourism and the previous adaptation works carried out to facilitate visits. In 1963, the cave was closed due to the damage produced by visitors’ breath, lighting and algal growth on the paintings. In 2001, an outbreak of the fungus Fusarium solani covered the walls and sediments. Later, black stains, produced by the growth of the fungus Ochroconis lascauxensis, appeared on the walls. In 2006, the extensive black stains constituted the third major microbial crisis. In an attempt to know the dispersion of microorganisms inside the cave, aerobiological and microclimate studies were carried out in two different seasons, when a climate system for preventing condensation of water vapor on the walls was active (September 2010) or inactive (February 2010). The data showed that in September the convection currents created by the climate system evacuated the airborne microorganisms whereas in February they remained in suspension which explained the high concentrations of bacteria and fungi found in the air. This double aerobiological and microclimate study inLascauxCave can help to understand the dispersion of microorganisms and to adopt measures for a correct cave management.

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