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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. ...

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. ...

Speleology in Kazakhstan

Shakalov on 11 Jul, 2012
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 throw is the vertical displacement of stratum along a fault plane [16].?

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Chemistry and Karst, White, William B.
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Karst environment, Culver D.C.
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Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
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Your search for reduction (Keyword) returned 119 results for the whole karstbase:
Showing 1 to 15 of 119
Sulfate reducing bacteria in microbial mats: Changing paradigms, new discoveries, 0000, Baumgartner Lk, Reid Rp, Dupraz C, Decho Aw, Buckley Dh, Spear Jr, Przekop Km, Visscher Pt,
Sulfate reducing bacteria (SRB) have existed throughout much of Earth's history and remain major contributors to carbon cycling in modern systems. Despite their importance, misconceptions about SRB are prevalent. In particular, SRB are commonly thought to lack oxygen tolerance and to exist only in anoxic environments. Through the last two decades, researchers have discovered that SRB can, in fact, tolerate and even respire oxygen. Investigations of microbial mat systems have demonstrated that SRB are both abundant and active in the oxic zones of mats. Additionally, SRB have been found to be highly active in the lithified zones of microbial mats, suggesting a connection between sulfate reduction and mat lithification. In the present paper, we review recent research on SRB distribution and present new preliminary findings on both the diversity and distribution of [delta]-proteobacterial SRB in lithifying and non-lithifying microbial mat systems. These preliminary findings indicate the unexplored diversity of SRB in a microbial mat system and demonstrate the close microspatial association of SRB and cyanobacteria in the oxic zone of the mat. Possible mechanisms and further studies to elucidate mechanisms for carbonate precipitation via sulfate reduction are also discussed

Tasmanian Cave Fauna: Character and Distribution, 1967, Goede, A.

The geology and nature of the caves is discussed. Cave development has been affected by glacial outwash and periglacial conditions which must be taken into account when considering the development and distribution of cave fauna. The food supply in the caves is limited by the absence of cave-inhabiting bats. Floods while adding to the food supply must be destructive to some forms of terrestrial cave life. The cave fauna consists entirely of invertebrates. The carab genus Idacarabus Lea contains the only troglobites found in Tasmania. A common troglophile throughout the island is Hickmania troglodytes (Higgins and Petterd) which belongs to a very small group of relict spiders. Five species of cave crickets are known from Tasmania and Flinders Island. Three species belong to the genus Micropathus Richards and show an interesting distribution pattern. A single species of glow-worm, Arachnocampa (Arachnocampa) tasmaniensis Ferguson occurs in a number of Tasmanian caves. It is more closely related to the New Zealand species than to glow worms found on the Australian mainland. Other terrestrial cave life is briefly discussed. Aquatic cave life is poorly known. The syncarid Anaspides tasmaniae (Thomson) has been recorded from several caves. It differs from epigean forms in reduction of pigment.


Symposium on Cave Surveying - Some Theoretical Aspects of the Routine Reduction of Cave Survey Data, 1970, Wilcock J. D.

The evolution of the Eastern North American Isopods of the Genus Asellus (Crustacea: Asellidae)., 1973, Fleming Laurence E.
This paper is the second in the three part series dealing with the evolution of the North American isopods of the genus Asellus. The generic status of Asellus is discussed with emphasis placed on the newly proposed genera of Henry and Magniez (1968). Use is made of comparative anatomical and where feasible statistical methods during this investigation. The first, shorter portion of the study deals with the presentation of evidence supporting the viewpoint that if 'Pseudobaicalasellus" is to be considered a valid genus then it must include the members of the Cannulus Group of Steeves (1965). The second portion of the study is concerned with the determination of the generic status of the eastern North American isopods. From the data presented it is felt that it is inadvisable to elevate species; groups of Asellus to the rank of genera. A generic diagnosis of the genus Asellus is presented. A list of North American species of the genus Asellus as well as a key to North American species of Asellus is included. The reduction to synonymy of certain nominal species of the genus Asellus is also given.

Ecological and evolutive aspects of the communities of temperate and tropical caves: observations on the biological cycles of some species of Ptomaphagus (Coleoptera Catopidae)., 1973, Sbordoni Marina Cobolli, Sbordoni Valerio
Differences between tropical and temperate cave communities are an important topic in the actual biospeleological thinking. Among the most striking differences is the paucity of terrestrial troglobites in tropical caves. This fact may depend on the higher energy input into tropical caves which lessens the selection pressures for energy-economizing troglobite adaptations. Consequently evolutionary rates would be slowed in tropical caves and, in a date group, troglobites would appear later in such caves than in temperate ones with lower energy input. In order to investigate this point the authors studied the degree of adaptation to the cave environment in two species of Mexican Ptomaphagus which, being phylogenetically related, probably descend from the same epigean ancestor. Among these species the first one, P. troglomexicanus Peck, lives in a typical temperate cave (i.e. cold, high altitude cave, with scarce food supply) in the Sierra de Guatemala (Tamaulipas), the other one, P. spelaeus (Bilimek), populates tropical caves (i.e. warm, lowland cave, with rich food supply) in the State of Guerrero. In addition a comparison is made with P. pius Seidlitz, an epigean species from southern Europe. The results show a striking difference between P. troglomexicanus on a side and the other two species. Differences chiefly concern morphological features such as relative antenna length, structural complexity (i.e. the number of sensilla) of the antenna chemioreceptor organs in the 70, 90, 100 segments, degree of reduction of eye, wing and pigmentation and physiological ones such as the length of the life cycle. The possible causes of these differences are discussed. According to the authors these differences appear due to the different selection pressures acting in the two types of caves. In addition a comparison between the "tropical cave" species, P. spelaeus, with the epigean one, P. pius, does not point out the differences that one could expect by the diverse ecology of these species. These observations support the idea that evolutionary rates in cavernicoles are strongly affected by the ecology of the cave, mainly depending on the degree of energy input, and are poorly consistent with the hypothesis that mutations affecting degenerative processes are selectively neutral.

Present state of the knowledge on hypogean Histeridae., 1973, Vomero Vincenzo
The author makes some considerations on troglobitic and endogeous world Histeridae. All these species present extreme reduction of eyes or are completely blind; all are wingless and only one is brachipterous. The Histeridae described here belong to the following genera: Speleacritus Jeannel and Spelaeabraeus Moro (Abraeinae), Sardulus Patrizi, Bacanius Le Conte, Troglobacanius Vomero and Geoculus Wenzel. (Dendrophilinae, Bacanius group). Finally some considerations on troglophylic and guanobitic Histeridae are made, reporting the recent discovery of a new genus and of some new species belonging to guanobitic biocoenosis of Mexican tropical caves.

The evolution of the Eastern North American Isopods of the Genus Asellus (Crustacea: Asellidae)., 1973, Fleming Laurence E.
This paper is the second in the three part series dealing with the evolution of the North American isopods of the genus Asellus. The generic status of Asellus is discussed with emphasis placed on the newly proposed genera of Henry and Magniez (1968). Use is made of comparative anatomical and where feasible statistical methods during this investigation. The first, shorter portion of the study deals with the presentation of evidence supporting the viewpoint that if 'Pseudobaicalasellus" is to be considered a valid genus then it must include the members of the Cannulus Group of Steeves (1965). The second portion of the study is concerned with the determination of the generic status of the eastern North American isopods. From the data presented it is felt that it is inadvisable to elevate species; groups of Asellus to the rank of genera. A generic diagnosis of the genus Asellus is presented. A list of North American species of the genus Asellus as well as a key to North American species of Asellus is included. The reduction to synonymy of certain nominal species of the genus Asellus is also given.

Ecological and evolutive aspects of the communities of temperate and tropical caves: observations on the biological cycles of some species of Ptomaphagus (Coleoptera Catopidae)., 1973, Sbordoni Marina Cobolli, Sbordoni Valerio
Differences between tropical and temperate cave communities are an important topic in the actual biospeleological thinking. Among the most striking differences is the paucity of terrestrial troglobites in tropical caves. This fact may depend on the higher energy input into tropical caves which lessens the selection pressures for energy-economizing troglobite adaptations. Consequently evolutionary rates would be slowed in tropical caves and, in a date group, troglobites would appear later in such caves than in temperate ones with lower energy input. In order to investigate this point the authors studied the degree of adaptation to the cave environment in two species of Mexican Ptomaphagus which, being phylogenetically related, probably descend from the same epigean ancestor. Among these species the first one, P. troglomexicanus Peck, lives in a typical temperate cave (i.e. cold, high altitude cave, with scarce food supply) in the Sierra de Guatemala (Tamaulipas), the other one, P. spelaeus (Bilimek), populates tropical caves (i.e. warm, lowland cave, with rich food supply) in the State of Guerrero. In addition a comparison is made with P. pius Seidlitz, an epigean species from southern Europe. The results show a striking difference between P. troglomexicanus on a side and the other two species. Differences chiefly concern morphological features such as relative antenna length, structural complexity (i.e. the number of sensilla) of the antenna chemioreceptor organs in the 70, 90, 100 segments, degree of reduction of eye, wing and pigmentation and physiological ones such as the length of the life cycle. The possible causes of these differences are discussed. According to the authors these differences appear due to the different selection pressures acting in the two types of caves. In addition a comparison between the "tropical cave" species, P. spelaeus, with the epigean one, P. pius, does not point out the differences that one could expect by the diverse ecology of these species. These observations support the idea that evolutionary rates in cavernicoles are strongly affected by the ecology of the cave, mainly depending on the degree of energy input, and are poorly consistent with the hypothesis that mutations affecting degenerative processes are selectively neutral.

Present state of the knowledge on hypogean Histeridae., 1973, Vomero Vincenzo
The author makes some considerations on troglobitic and endogeous world Histeridae. All these species present extreme reduction of eyes or are completely blind; all are wingless and only one is brachipterous. The Histeridae described here belong to the following genera: Speleacritus Jeannel and Spelaeabraeus Moro (Abraeinae), Sardulus Patrizi, Bacanius Le Conte, Troglobacanius Vomero and Geoculus Wenzel. (Dendrophilinae, Bacanius group). Finally some considerations on troglophylic and guanobitic Histeridae are made, reporting the recent discovery of a new genus and of some new species belonging to guanobitic biocoenosis of Mexican tropical caves.

Use of a Computer Program for Cave Survey Data Reduction, 1974, Rutherford John M. , Amundson Robert M.

Size and growth of the eyes of the troglobitic Salamander Typhlotriton spelaeus., 1974, Besharse Joseph C. , Brandon Ronald A.
The eyes of larval T. spelaeus grow by negative allometry, but in allometric coefftcients they are not greatly different from E. lucifuga. The major differences in eye size, both absolute and relative to body size, between T~ spelaeus and E. lucifuga are established prior Io the larval growth period. The eyes of T. spelaeus cease to grow at metamorphosis and are reduced in size thereafter. In addition, there is increased individual variability and bilateral asymmetry of eye size in adult T spelaeus compared to both adulI E lucifuga and larval T. spelaeus. This variability, expressed as relative dispersion about mean eye size, is significantly greater than in E luci.fuga, and appears to result from three factors: 1) postmetamorphic cessation of eye growth, 2) wide variation in body size and eye size al metamorphosis, and 3) postmetamorphic shape changes and reduction of eye size.

Millipedes in the collection of the AMCS. III. Reddellobus troglobius, n. gen., n. sp., an unusual troglobite from Puebla, Mexico, and other records of the Family Spirobolellidae (Order Spirobolida, Class Diplopoda)., 1975, Causey Nell B.
During the past several years, members of the Association for Mexican Cave Studies have made some surprising additions to the knowledge of the invertebrate fauna of Mexico. None of their finds is more exciting than the species described here, a millipede much larger than the nearest epigean relative in an order outstanding for its scarcity of troglobitic adaptations. The absence of ocelli and the reduction of body pigment in the known epigean typhlobolellids suggest that they are deep humus dwellers preadapted for cave life.

Sulfate reduction and sulfur deposition in the Lower Fars Formation, northern Iraq, 1977, Alsawaf Fds,

Genesis of paleokarst and strata-bound zinc-lead sulfide deposits in a Proterozoic dolostone, northern Baffin Island, Canada, 1984, Olson R. A. ,
Society Cliffs Formation; episodes of karstification since its deposition. During the first karst episode an evaporite solution-collapse breccia formed ubiquitously on the western Borden Peninsula. During the second karst episode a holokarst developed and an integrated cave system was formed. The caves subsequently were filled with sulfides and carbonate minerals; several interesting sedimentary structures exist in the zinc-lead sulfide deposits. The ore fluid and contained metals are postulated to have been derived during a late-stage dewatering of the black shale that underlies the Society Cliffs Formation. Sulfide deposition may have been caused by chemical reduction of sulfate that existed in the ore fluid when the fluid entered hydrocarbon-filled caves. During the third and fourth episodes of karstification, only merokarst developed in the Society Cliffs Formation. Karst effects which formed during these episodes include oxidized sulfide deposits and surface solution corridors.--Modified journal abstract

Evolutionary Reduction by Neutral Mutations: Plausibility Arguments and Data From Amblyopsid Fishes and Linyphiid Spiders, 1985, Poulson, Thomas L.

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