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KarstBase a bibliography database in karst and cave science.
Featured articles from Cave & Karst Science Journals
Characterization of minothems at Libiola (NW Italy): morphological, mineralogical, and geochemical study, Carbone Cristina; Dinelli Enrico; De Waele Jo
Chemistry and Karst, White, William B.
The karst paradigm: changes, trends and perspectives, Klimchouk, Alexander
Long-term erosion rate measurements in gypsum caves of Sorbas (SE Spain) by the Micro-Erosion Meter method, Sanna, Laura; De Waele, Jo; Calaforra, José Maria; Forti, Paolo
The use of damaged speleothems and in situ fault displacement monitoring to characterise active tectonic structures: an example from Zapadni Cave, Czech Republic , Briestensky, Milos; Stemberk, Josef; Rowberry, Matt D.;
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 biotope (Keyword) returned 34 results for the whole karstbase:
Showing 16 to 30 of 34
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The new subspecies Stenasellus skopljensis thermalis, from Banja Luka (Bosnie, Yugoslavia) is described. From the ecological point of view this form differs from the others because it inhabits underground waters of elevated temperature (240°C). Another constantly abundant species, St. hungaricus thermalis Mestrov, also occurs in Yugoslavia under the same ecological conditions, in the warm springs of Podsused near Zagreb. This indicates that these underground waters at elevated temperature are not accidental but preferred habitats for these forms, and confirms once again that thermal waters of this type are the biotopes-refuges in which certain relic forms are retained.
The spatial distribution of 113 individuals from the species Meta menardi Latr. (Argiopidae) divided in 10 different populations living in 8 Belgian caves has been studied. A grouping test and the calculation of R according to Clark et Evans (1954), based on the measurement of the distance to the nearest neighbour, have been used. Results show that the individuals are distributed at random inside their biotope.
The spatial distribution of 113 individuals from the species Meta menardi Latr. (Argiopidae) divided in 10 different populations living in 8 Belgian caves has been studied. A grouping test and the calculation of R according to Clark et Evans (1954), based on the measurement of the distance to the nearest neighbour, have been used. Results show that the individuals are distributed at random inside their biotope.
Description of a small warm cave situated along the Mediterranean shore; the temperature of water varies from 14 to 19°C. Inhabiting this cave is Niphargus altagahizi, a new species related to orcinus s.l. group. Description of this species and comparison with the other Lebanese species, N. nadarini.
Description of a small warm cave situated along the Mediterranean shore; the temperature of water varies from 14 to 19°C. Inhabiting this cave is Niphargus altagahizi, a new species related to orcinus s.l. group. Description of this species and comparison with the other Lebanese species, N. nadarini.
Some important morphological features, which are discussed here, point out that the Stenasellids (Crustacea Isopoda Asellota) must be considered as a true family (Stenasellidae), independent from the Asellidae. A definition and a renewed diagnosis of the Stenasellidae Dudich, 1924, are given. Their relationships must be pursued, especially in the marine Parastenetroidea and in the psammic Microcerberidae. Until 1938, the group was known only from subterranean waters of southern Europe. Now, several genera and many thermophile species from north-tropical underground waters have been discovered in Africa (5 gen., 12 sp.), Asia (1 gen., 2 sp.) and Central America (1 gen., 4 sp.). The Stenasellids are very active burrowers. Such a behaviour explains how their phyletic lines had colonized the continental underground waters, by migrations from the littoral gravels to the underflow of rivers, phreatic alluvial waters and fìnally, to the karstic waters. The typical medium for the life of the group is represented by the phreatic zones of African shields arenas. In European phyletic lines, the speciation seems to be linked with tertiary subsidences (within the Tyrrhenian area, for the line of Stenasellus virei). The European species which have survived quaternary glaciations may have diversified themselves (rising of subspecies), recolonizing newly vacant biotopes in postglacial ages.
Thanks to intensive exploration and to new methods for capturing aquatic underground fauna. 117 localities are now known for Stenasellus virei. The description of some typical biotopes suggests that the species lives as well in karstic waters as in phreatic ones, inside the different environment of the hydrogeological classification of subterranean waters. St. virei buchneri and St. v. hussoni are almost cavernicolous. St. v. angelieri is distributed in the underground waters of Catalonia. St. v. boui is located in the underflow of Salat river basin. St. v. virei is widely distributed in the alluvial water-level of Garonne and Ebro rivers basins. The dispersion of St. virei into the alluvial environment explains the process of colonization of continental underground waters. It explains also the existence of an apparently insulated population into the sink-hole of Padirac. The actual distribution of the five subspecies is explained by important restrictions of the area in quaternary glacial ages, followed by local (in the water-level of the tributaries of Garonne river) spreading during postglacial time. The postglacial reconquest of the Salat river underflow by this species seems to have been responsible for the latest subspeciation (St. v. boui). The endemic populations of fossil karstic systems seem to have an abnormal composition. They include unusually large adults, juvenile stages being rare. They differ from the phreatic populations, which exhibit a normal distribution is size groups, with a formal percentage of juveniles. These differences between karstic and interstitial populations may result from the fact that in caves, Sr. virei is often insulated from its original phreatic biocoenosis: an intraspecific competition between size classes has taken the place of normal heterospecific struggle for existence.
P. walteri, an eyeless species of tiny size and thin body, shows numerous original characters. By its general morphology, it is one form of Asellid best adapted to the phreatic waters where it exists in large settlements. It is also able to live in the psammic biotope in a manner similar to Microparasellids. The females lay only 6 to 10 normal sized eggs. There is no indication of oostegits outside the breeding period. In some populations, the small number of eggs, correlated with the small size, seems to be compensated by a sex-ratio favorable so the females.
An analysis of the population in the hyporheic medium of the Drava river shows that Proasellus slavus ssp. n. is one of the smallest known Asellids. It is living in an interstitial biotope as a permanent population in which density varies in space and time. Our observations show that reproduction takes place throughout the year, however with a maximum rate at the beginning of summer. Females may produce a relatively great number of offspring, notwithstanding the smallness of the species.
19 species of ciliates were found in interstitial biotopes of the Fulda Headwater. Two of these were new: Haplocaulus hengsti, n.sp. and Epistylis rotti, n.sp. (Peritrichida). The number of ciliate species decreases from the surface down so deeper layers; in a depth of 50 cm, only three species were found: Haplocaulus hengsti and Epistylis rotti and another small ciliate Trachelophyllum apiculatum. There was little detritus in this layer, and so, the abundance of the ciliates was low. On the other hand, there is little predation in deeper layers of stygorhithral sand and gravel. Small, long and thin ciliates seem so be specially adapted to life in deeper regions of the stygornithral Stygorhithral ciliates are related to custygal species with respect to several characteristics of their morphology and general biology.
The locomotory activity of adult cave fishes Astyanax jordani was recorded in isolation in the following light and temperature conditions: constant conditions (100 Lx; 200C), in a light cycle (LD:11/11 -10 Lx -100 Lx) and in a temperature cycle (11/11; 17/20, 19/22, 20/23, 27/30 °C). All longitudinal time series extended for a minimum of 30 days. Results show: (1) That no circadian regulation appears in constant conditions; (2) that passive entrainment occurs in LD (Amplitude: 90 Lx) and in periodic temperature conditions (Amplitude: 3°C). The entrainment effect damps out and varies individually; (3) that the mean activity increases with temperature; (4) The adjustment of activity to periodic signals is individually stable. These results suggest that A. Jordani is devoid of any endogenous oscillator of the circadian type. The observed thermal adaptation could have the following functions: (1) To increase the level of activity in function of the thermal level under the form of passive entrainment; (2) To enhance the exploratory behaviour of the fish in search of a thermal preference allowing the animal to keep inside a well defined zone of the subterranean biotope in relation to small local temperature changes.
Epigean and cave populations of A. fasciatus (Characidae, Pisces) differ in a series of morphological physiological, and ethological features. The interfertility of these populations made possible a genetic analysis of organs characteristic of interspecific divergence. The study of the regressive organs "eye" and "melanophore system" on the one hand and that of the constructively improved "gustatory equipment and feeding behaviour" on the other yielded identical principles of genetic manifestation: (1) All features have a polygenic basis with an at least di- to hexahybrid inheritance. (2) All polygenes have the same amount of expressivity. (3) After recombination of a minimum number of genes, discontinuous distributions (threshold effects) develop. (4) All features are independently inherited. (5) The genes responsible for a feature are unspecific. In the case of the eye this means that no "lens-" or "retinagenes" are analyzed; due to developmentally physiological interdependence within complex structures, only so-called "eye-genes" have as yet been described. Because of the developmentally physiological interdependence of complex organs, the process of reduction proceeds as a diminution in size, that of constructive evolution as enlargement. In both cases different allometric correlations of the single structures can be found. The convergent reduction of eyes in cave animals is caused by the loss of stabilizing selection which normally keeps the eye in its appropriate adapted form. It is not directional selection pressure, like f. ex. energy economy, but mutation pressure that causes eye reduction. By this, random mutations, which are mostly of deleterious character, are accumulated. The principles of regressive evolution are not restricted to the development of cave species. The absence of stabilizing selection regularly occurs during transitional evolutionary phases. These are f. ex. initial stages of speciation which may be observed when biotopes with little or no interspecific competition are colonized by an invader. Genotypic and phenotypic variability now arise and equilibria become punctuated, because stabilizing selection for a specific ecological niche which has once been acquired by the invading species is no longer acting. Examples include the evolution of species flocks in geologically young lakes or oceanic islands. Rapidly increasing variability now secondarily provides the material for directional selection which radiates such species into vacant niches. Genetic threshold effects as described above may accelerate this process. Variability will finally become lower again under the influence of inter- and intraspecific competition. A new equilibrium is attained.
The mountain shelters in the karst regions of Greece, Crete, Turkey and Iran - The concept of mountain shelters in karst region exists from the Prehistory, especially with rock-shelters and karstic caves. In the high karsts of Greece, Crete, Taurus (Turkey) and Zagros (Iran), the highlanders have survived during the invasions and wars because of their natural bastions. At the junction of civilisations and religions (Christians and Moslems), the karst biotope, one of the natural environment the most used by human people to guard against enemy and to breed (sheep-farming). Because of grazing and destruction of forests (particularly by Byzantine people and Venitians), the mediterranean karst mountain grew poorer.
A multidisciplinary approach has produced an exceptional chronological log of climatic patterns for the Upper Pleistocene sequence of Gigny Cave (Jura, France) covering the Pre-Eemian, Eemian Interglacial, Middle Glacial and Upper Pleniglacial, as well as a part of the Holocene. Multivariate analysis (correspondence and component analysis) of rodent associations from the sequence is used here to characterize the different climatic stages in terms of relative temperature, plant cover and moisture. Faunal analysis establishes: (1) positive and negative correlations among the variations of the different species; (2) the significance of axis 1 (component analysis) which, in terms of temperature, opposes cold environments with contrasted continental biotopes; (3a) the significance of axis 2 (component analysis), which reflects vegetation patterns ranging from open to closed habitats; (3b) the significance of axis 3 (component analysis), which expresses trends in moisture; (4) various correlations between faunal and climatic parameters (temperature, plant cover and moisture); (5) evaluation of faunal diversity (Shannon index ranging from 0.74 to 2.27) showing that diversity increases with temperature and the complexity of vegetation, but is not sensitive to moisture. Lastly, the comparison of multivariate methods with the weighted semi-quantitative Hokr method shows the complementarity of the two approaches, the first methods quantifying climatic parameters while the second seems to provide more precise evaluations of the main seasons of rainfall
After the successful colonization of a single ancestral species in the Hawaiian Islands, planthoppers of the cixiid genus Oliarus underwent intensive adaptive radiation resulting in 80 described endemic species. Oliarus habitats range from montaneous rain forests to dry coastal biotopes and subterranean environments. At least 7 independant evolutionary lines represented by different species have adapted to lava tubes on Molokai (1), Maui (3), and Hawaii Island (3). Behavioral and morphological studies on one of these evolutionary lines on Hawaii Island, the blind, flight- and pigmentless Oliarus polyphentus have provided evidence for reproductive isolation between allopatric populations which may in fact be separate species. Significant differences in song parameters were observed even between populations from neighbouring lava tubes, although the planthoppers are capable of underground migration through the voids and cracks of the mesocavernous rock system which is extant in young basalt: after a little more than 20 years, lava tubes within the Mauna Ulu 1974 flow had been colonized by O. 'polyphenius" individuals, most probably originating from a near-by forestkipuka. Amazingly, this species complex is found on the youngest of the Hawaiian Islands, with probably less than 0.5 m.y., which suggests rapid speciation processes. Field observations have led to the development of a hypothesis to match underground speciation with the dynamics of vegetational succession on the surface of active volcanoes. Planthopper range partitioning and geographic separation of populations by young lava flows, founder events and small population size may be important factors involved in rapid divergence.
Results 16 to 30 of 34
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