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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 tri-cam is a metalic devise placed in holes or cracks for use as an anchor [25]. compare chock?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
See all featured articles
Featured articles from other Geoscience Journals
Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
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Your search for algae (Keyword) returned 58 results for the whole karstbase:
Showing 46 to 58 of 58
Characterization of cave aerophytic algal communities and effects of irradiance levels on production of pigments, 2008, Mulec J. , Kosi G. , And Vrhovek D.
Aerophytic algae grow on various substrata under favourable ecological conditions. In the illuminated parts of caves, where relative humidity reaches 100%, they colonize sediments, rocky surfaces, and artificial materials. An aerophytic algal community from the cave entrance is composed almost exclusively of cyanobacteria, in contrast to lampenflora where green algae become more dominant. In the later stage of species succession in the lampenflora community, cyanobacteria are more abundant and thus community structure becomes more similar to the community from the cave entrance. Absence of correlation between photon flux density and chlorophyll a concentration indicates that substratum characteristics at the micro level notably influence algal growth. Chl a concentration per surface unit in the case of the epilithic algae from the cave entrance is lower (max. 1.71 mg cm22) compared to that for the lampenflora algae (max. 2.44 mg cm22). At cave temperatures, the light saturation point is quickly reached. At 9.0 uC and frequent low photon flux densities in a cave entrance and around lamps in show caves, biosynthesis of accessory photosynthetic pigments for two typical cave aerophytic organisms, cyanobacterium Chroococcus minutus and green alga Chlorella sp., is considerably elevated.

MICROORGANISMS IN HYPOGEON: EXAMPLES FROM SLOVENIAN KARST CAVES, 2008, Mulec, Janez

In caves microorganisms inhabit distinct habitats where they develop various interactions. As an evidence of microbial activity several features can be identified. Microorganisms are involved both in lithogenic and litholitic processes. Besides heterotrophs in caves autotrophic organisms can be also expected. Some cyanobacteria and microalgae in caves can survive even at photon flux densities lower than their photosynthetic compensation point. In the paper up-to-date identified groups of microorganisms (bacteria, cyanobacteria, microalgae, fungi and protozoa) with their localities in Slovenian caves are presented. Especially bacteria from caves, as the most diverse group, offer immense biotechnological and bioremediation potential. In caves microbial biomass can be considered a considerable food source for cave-dwelling higher organisms. Caves in Slovenia offer great chances to discover new species, as was fungus Mucor troglophilus discovered in association with the cave cricket Troglophilus neglectus.


Lampenflora algae and methods of growth control, 2009, Mulec J. And Kosi G.
Karst caves are unique natural features and habitats where specialized organisms live. Some caves are also important as cultural heritage sites. In recent decades, many caves have experienced intensified tourist visits. To attract visitors, artificial illumination was installed that changed conditions in the caves. As a result, communities of organisms called lampenflora develop in close and remote proximity to lights. These phototrophic organisms are inappropriate from an aesthetic point of view and cause the degradation of colonized substrata, which is a particular problem in caves with prehistoric art. Key factors that allow lampenflora to grow are light and moisture. Illuminated spots in caves can be quickly colonized by algae, some of which have broad tolerances for different substrata. Several phototrophs can survive in caves even at photon flux densities lower than the photosynthetic compensation point. In this paper, the pros and cons of physical, chemical, and biological methods to control phototrophic growth are reviewed and discussed. Experiences in show caves can be helpfulin controlling undesirable algal growth in other environments.

Exploring the secrets of the three-dimensional architecture of phototrophic biofilms in caves, 2009, Roldn M. And Hernndezmarin M.
Caves with dim natural light, and lighted hypogean environments, have been found to host phototrophic microorganisms from various taxonomic groups. These microorganisms group themselves into assemblies known as communities or biofilms, which are associated with rock surfaces. In this work, the phototrophic biofilms that colonise speleothems, walls and floors in three tourist caves (Spain) were studied. Confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM) were used to study these organisms and acquire three-dimensional data on their biofilm structure. CLSM was used in a multi-channel mode whereby the different channels map individual biofilm components. Cyanobacteria, green microalgae, diatoms, mosses and lichens were found to be grouped as biofilms that differed according to the sampling sites. The biofilms were classified into six types regarding their environmental conditions. These types were defined by their constituent organisms, the thickness of their photosynthetic layers and their structure. Light-related stress is associated with lower biofilm thickness and species diversity, as is low humidity, and, in the case of artificially illuminated areas, the duration of light exposure

Communities of photosynthetic organisms developing under artificial lighting conditions in the developed section of the Mramornaya show cave, 2009, Mazina S. E.

Morphology and origin of coastal karst landforms in Miocene and Quaternary carbonate rocks along the central-western coast of Sardinia (Italy), 2009, De Waele Jo, Mucedda Mauro, Montanaro Luca

In the area of Punta Funtanas (Arbus, Central-West Sardinia) somesmall surfaces ofMiocene limestones crop out, partially covered with Quaternary calcarenites and Plio-Quaternary basalts. The biggest of these outcrops forms a fossilwave-cut shore platformof up to 50m wide with an altitude above sea level of approximately 4–5m. On this platformawide variety of dissolution landforms can be observed. Thesemorphologies are related to the influence of the seawater (zone of wave action, marine splash and spray zone, up to progressively more continental environments) and to biokarst processes (erosional action ofmarine organisms, algae andmicro-organisms) and are arranged in bands parallel to the coast, corresponding to different morphological zones.

This paper describes all the karst landforms observed in this coastal area from a morphological and genetic point of view.


Exploring the secrets of the three-dimensional architecture of phototrophic biofilms in caves, 2009, Roldn M. , Hernndezmarin M.

Caves with dim natural light, and lighted hypogean environments, have been found to host phototrophic microorganisms from various taxonomic groups. These microorganisms group themselves into assemblies known as communities or biofilms, which are associated with rock surfaces. In this work, the phototrophic biofilms that colonise speleothems, walls and floors in three tourist caves (Spain) were studied. Confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM) were used to study these organisms and acquire three-dimensional data on their biofilm structure. CLSM was used in a multi-channel mode whereby the different channels map individual biofilm components. Cyanobacteria, green microalgae, diatoms, mosses and lichens were found to be grouped as biofilms that differed according to the sampling sites. The biofilms were classified into six types regarding their environmental conditions. These types were defined by their constituent organisms, the thickness of their photosynthetic layers and their structure. Light-related stress is associated with lower biofilm thickness and species diversity, as is low humidity, and, in the case of artificially illuminated areas, the duration of light exposure.


SPATIAL AND TEMPORAL HYDROCHEMICAL VARIATIONS OF THE SPRING-FED TRAVERTINE DEPOSITING STREAM IN THE HUANGLONG RAVINE, SICHUAN, SW CHINA, 2010, Wang H. , Liu Z. , Zhang J. , Sun H. , An D. , Fu R. , Wang X.
Automatic hydrochemical logging and in situ titration combined with laboratory 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 with snowmelt water and by renewed CO2 from some downstream springs. The chemistry of Huanglong Spring itself was stable at a diurnal scale though it 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, which indicates that the deposition of travertine was faster during the daylight hours. This was due to the combined e?ects of higher water tempera-tures and higher aquatic algae photosynthesis. In addition, it was found that the phosphate concentration in the stream in-creased remarkably downstream in the tourist midseason, in-dicating water pollution by tourism activities. ?e 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, which needs to be given more comprehensive study and tackled in future for the protection of these world famous travertine deposits.Keywords: hydrochemical var

First Records of Polychaetous Annelids from Cenote Aerolito (Sinkhole and Anchialine Cave) in Cozumel Island, Mexico, 2011, Frontanauribe S. C. , Sollsweiss V.

In this study, polychaetous annelids are recorded for the first time in Mexican cenotes and anchialine caves. These organisms were collected in the Cenote Aerolito (Cozumel Island, on the Caribbean coast of Quintana Roo) during three sampling events from February 2006 to April 2008, among algae, roots of mangroves, and in karst sediments. A total of 1518 specimens belonging to five families (Paraonidae, Capitellidae, Nereididae, Dorvilleidae, and Syllidae), ten genera, and eleven species were collected. In the cave system, two specimens of the amphinomid Hermodice carunculata were found. This cenote and its biota are now in danger of disappearing because of a marina construction project in its western shore.


Development of a Specific Quantitative Real-Time PCR Assay to Monitor Chlorella DNA: A Case Study from Mammoth Cave National Park, Kentucky, USA , 2011, Fowler, Richard F.

Estimates of phytoplankton abundance are important parameters
watched by stewards of water quality and freshwater ecology in rivers, streams, and reservoirs. A targeted phytoplankton assay
for Chlorella DNA was developed to estimate the abundance of the predominant species of green algae in surface waters of Mammoth Cave National Park (MACA) in Kentucky, USA. The phytoplankton community in the Green River in MACA has been shown to consist of 95% Chlorella sp. (Wullschlegger et al., 2003). Chlorella 18S rRNA gene sequences were amplified and quantified using Quantitative Real-Time PCR (qPCR) with primers
specific for the family Chlorellaceae in the class Trebouxiophyceae,
order Chlorellales. Concentrations of Chlorella DNA in river water samples were measured by comparison to a standard curve generated by DNA extracted from a live laboratory culture of C. vulgaris. DNA isolated from other sources including bacteria,
amoebae, fungi, decapods, insects, cave sediment, and a different
green alga, Chlamydomonas, produced no PCR products and thus did not interfere with the detection and quantification of Chlorella DNA. The assay proved quantitative over more than four orders of magnitude with a method detection limit (MDL) of approximately 2.3 x104 cells/L. Presence or absence of Chlorella
DNA could be demonstrated at concentrations ten to 100 times lower than the calculated MDL. Chlorella was detected in lampenflora samples from three tourist trails, and Chlorella was absent from sediment samples off tourist trails that were known to contain high concentrations of bacterial DNA. Demonstration of the utility of the technique was illustrated by a case study in Mammoth Cave National Park to determine Chlorella concentrations
at various sampling sites of karst surface streams where invasive zebra mussels are a threat to native species.


Flora of a small lava cave near Laki, Iceland, 2012, Pentecost, Allan

Twenty nine phototrophic taxa are reported from a small volcanic cave. These included five cyanobacteria, two of which are heterocystous nitrogen-fixers, and nine diatoms, several of which have previously been reported from caves. Of the five lichen taxa, two are foliose nitrogen-fixers, suggesting that combined nitrogen was in short supply. The aerophytic flora show similarities with communities from limestone caves suggesting that low light and high humidity are of overriding importance for some taxa.


La Serreta endokarst (SE Spain): a sustainable value?, 2013, Asencio A. D. , Espinosa T.

La Serreta endokarst (SE Spain), which UNESCO declared a World Heritage Site in 1998, was considered a sanctuary with cave art and one of the most important archaeological sites in the Mediterranean region for both the remains it hosts and the spectacular karstic landscape at the site.

To coincide with the 40th anniversary of its discovery, the La Serreta cave-chasm was adapted for public use with the intention of showing visitors the remains, which date back to prehistoric times. The solution included attempts to minimize contact with the valuables in the cave in order to alter the existing remains as little as possible and to make good use of the magnificent interpretative conditions of such a unique place by showing the spectacular views over the Los Almadenes canyon, where the Segura River flowed, which is now a viewpoint over the void.

In order to determine the sustainability of the endokarst, the Karstic Sustainability Index (KSI) was applied as a standard measure of sustainable development practices in karstic environments, which employs indicators for the three domains: use of social, economic and environmental resources. By applying this index, La Serreta endokarst was found to be progressing towards the sustainable management of karst resources.

 
 

The influence of light attenuation on the biogeomorphology of a marine karst cave: A case study of Puerto Princesa Underground River, Palawan, the Philippines, 2015, Coombes Martin A. , La Marca Emanuela C. , Naylor Larissa A. , Piccini Leonardo, De Waele Jo, Sauro Francesco

Karst caves are unique biogeomorphological systems. Cave walls offer habitat for microorganisms which in-turn have a geomorphological role via their involvement in rock weathering, erosion and mineralisation. The attenuation of light with distance into caves is known to affect ecology, but the implications of this for biogeomorphological processes and forms have seldom been examined. Here we describe a semi-quantitative microscopy study comparing the extent, structure, and thickness of biocover and depth of endolithic penetration for samples of rock from the Puerto Princesa Underground River system in Palawan, the Philippines, which is a natural UNESCO World Heritage Site.

Organic growth at the entrance of the cave was abundant (100% occurrence) and complex, dominated by phototrophic organisms (green microalgae, diatoms, cyanobacteria, mosses and lichens). Thickness of this layer was 0.28 ± 0.18 mm with active endolith penetration into the limestone (mean depth = 0.13 ± 0.03 mm). In contrast, phototrophs were rare 50 m into the cave and biofilm cover was significantly thinner (0.01 ± 0.01 mm, p b 0.000) and spatially patchy (33% occurrence). Endolithic penetration here was also shallower (b0.01mm, p b 0.000) and non-uniform. Biofilm was found 250 m into the cave, but with a complete absence of phototrophs and no evidence of endolithic bioerosion.

We attribute these findings to light-induced stress gradients, showing that the influence of light on phototroph abundance has knock-on consequences for the development of limestone morphological features. In marine caves this includes notches, which were most well-developed at the sheltered cave entrance of our study site, and for which variability in formation rates between locations is currently poorly understood.


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