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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. ...
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,
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. ...
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 temperature efficiency is an efficiency factor defined by thornthwaite for different climates. see also thornthwaite.?
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Search KARSTBASE:
KarstBase a bibliography database in karst and cave science.
Featured articles from Cave & Karst Science Journals
Bacterial metabolism, involving redox reactions with carbon, sulfur, and metals, appears to have been important since the dawn of life on Earth. In the Archean, anaerobic bacteria thrived before the Proterozoic oxidation of the atmosphere and the oceans, and these organisms continue to prosper in niches removed from molecular oxygen. Both aerobes and anaerobes have profound effects on the geochemistry of dissolved metals and metal-bearing minerals. Aerobes can oxidize dissolved metals and reduced sulfur, as well as sulfur and metals in sulfide minerals can contribute to the supergene enrichment of sulfide ores, and can catalyze the formation of acid mine drainage. Heterotrophic anaerobes, which require organic carbon for their metabolism, catalyze a number of thermodynamically favorable reactions such as Fe-Mn oxyhydroxide reductive dissolution (and the release of sorbed metals to solution) and sulfate reduction. Bacterial sulfate reduction to H2S can be very rapid if reactive organic carbon is present and can lead to precipitation of metal sulfides and perhaps increase the solubility of elements such as silver, gold, and arsenic that form stable Me-H2S aqueous complexes. Similarly, the bacterial degradation of complex organic compounds such as cellulose and hemicellulose to simpler molecules, such as acetate, oxalate, and citrate, can enhance metal solubility by forming Me organic complexes and cause dissolution of silicate minerals. Bacterially induced mineralization is being used for the bioremediation of metal-contaminated environments. Through similar processes, bacteria may have been important contributors in some sedimentary ore-forming environments and could be important along the low-temperature edges of high-temperature systems such as those that form volcanogenic massive sulfides
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.
Recognition and understanding of the important role of sulfur redox processes in developing karst has grown over the last25 years with the discovery of remarkable sulfur-rich caves worldwide and advances in geomicrobiology. Recent work hasshown that microbes interact with hydrocarbons, calcium sulfate bedrock, magmatic fluids, and sulfide ore minerals toreduce gypsum/anhydrite to calcite, produce hydrogen sulfide and sulfuric acid, convert limestone to gypsum, in crease porosity in carbonate bedrocks, precipitate massive sulfur, and deposit Mississippi Valley-Type (MVT) ores. These processesare most active in the shallow phreatic and vadose-phreatic subsurface, where transitions between aerobic and anaerobicconditions exist.
