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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 invertebrates (Keyword) returned 52 results for the whole karstbase:
Showing 16 to 30 of 52
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Cueva de Villa Luz (a.k.a. Cueva de las Sardinas) in Tabasco, Mexico, is a stream cave with over a dozen H2S-rich springs rising from the floor. Oxidation of the H2S in the stream results in abundant, suspended elemental sulfur in the stream, which is white and nearly opaque. Hydrogen sulfide concentrations in the cave atmosphere fluctuate rapidly and often exceed U.S. government tolerance levels. Pulses of elevated carbon monoxide and depleted oxygen levels also occasionally enter the cave.
Active speleogenesis occurs in this cave, which is forming in a small block of Lower Cretaceous limestone adjacent to a fault. Atmospheric hydrogen sulfide combines with oxygen and water to form sulfuric acid, probably through both biotic and abiotic reactions. The sulfuric acid dissolves the limestone bedrock and forms gypsum, which is readily removed by active stream flow. In addition, carbon dioxide from the reaction as well as the spring water and cave atmosphere combines with water. The resultant carbonic acid also dissolves the limestone bedrock.
A robust and diverse ecosystem thrives within the cave. Abundant, chemoautotrophic microbial colonies are ubiquitous and apparently act as the primary producers to the cave’s ecosystem. Microbial veils resembling soda straw stalactites, draperies, and “u-loops” suspended from the ceiling and walls of the cave produce drops of sulfuric acid with pH values of <0.5-3.0 ±0.1. Copious macroscopic invertebrates, particularly midges and spiders, eat the microbes or the organisms that graze on the microbes. A remarkably dense population of fish, Poecilia mexicana, fill most of the stream. The fish mostly eat bacteria and midges. Participants in an ancient, indigenous Zoque ceremony annually harvest the fish in the spring to provide food during the dry season.
Summary of karst features and karst biology of Christmas Island (Indian Ocean). Limestone caps a basalt volcanic seamont. Coastal caves entered from sea cliffs. Uplifted coastal caves reflect past sea levels. Also plateau caves, fissure caves and one cave in basalt. Subterranean fauna was sampled via caves, boreholes and springs. Fauna includes swiftlets and a diverse assemblage of invertebrates, both terrestrial and aquatic (including anchialine). At least 12 underground species endemic to island.
Investigations of macroinvertebrate communities in the Reka, a karst river, were carried out at three sampling sites. We used the so-called "kick sampling" semi-quantitative method, sampling every three months from July 1995 to June 1996. This method proved to be a suitable sampling procedure for identifying macroinvertebrate community structures and for their further analysis. The differences in physical and chemical factors, which indicated seasonal changes, affected the changes in the living communities of macroinvertebrates and were evaluated using diversity, saprobic and biotic indices. The Chandler biotic score changed in proportion to the saprobic value and qualitative classes, and proved to be the best index for assessing water quality in the Reka. Assessments made using the Shannon-Wiener diversity index corresponded with those made using a modified saprobic index and the average Chandler biotic score. The river, with an actual biological optimum, does not exert any substantial negative impact on the underground streams of Škocjanske Jame, into which it flows.
This ecological study deals with the structure of the fauna in a Karst river, classified into different feeding. From the source to the swallow hole the proportion of suspension feeders, filterer-collectors and shredders diminished, but the proportion of deposit feeders and grazers increased. The proportion of predators was roughly the same at all sampling sites. Biological research showed that in the Reka river optimal food exchange with slightly increased trophic activity takes place, but it does not have a negative effect on the community structure of macroinvertebrates.
Black coating of hard substrates by Mn and Fe oxides has long been reported from shallow, dark, submarine caves. However, these littoral metallic deposits have never been studied in detail, despite expected analogies with deep-sea polymetallic crusts. Submarine caves are characterized by darkness and low rates of exchanges with the open sea. Lack of primary production and confinement of inner water bodies result in marked oligotrophy and extremely reduced biomass, i.e. conditions close to those prevailing in deep-sea habitats. Field evidences suggested that the formation of Mn-Fe coatings was closely tied to these particular environmental conditions. The goal of this study was to examine the detailed features of Mn-Fe coatings from dark caves with different local conditions, and to try to identify the processes responsible for their deposition. Study sites and methods Three sublittoral, single-entrance, caves were sampled by scuba diving along the coasts of Provence (France, Mediterranean Sea) (fig. 1). The first site is a large karstic cave (Tremies Cave, 16 m depth at entrance floor, 60 m long; Marseille-Cassis area) with an ascending profile which results in a buffered thermal regime and markedly oligotrophic conditions due to warm water trapping in its upper part (fig. 1 and 2). Wall fragments were sampled at 30 m (medium confinement : zone B) and 60 in (strong confinement : zone C) from the cave entrance. The second site is a large tubular cavity open in conglomerate formations (3PP Cave, 15 m depth at entrance floor, 120 m long; La Ciotat) with a descending profile which results in relative permanence of winter temperatures within the inner parts, complex water circulation and presumed greater input of sedimented particles than in the preceding cave (fig.1 and 2). Wall samples were taken at 25 m, 70 in and 100 m from entrance. The third site is a small, horizontal, cave open in quartzite formations (Bagaud Cave, 7 in depth at entrance floor, about 10 m long; WNW of Port-Cros Island, bay of Hyeres). Sampling was performed on walls of a narrow corridor between an anterior room and a smaller inner room. A sporadic outflow of continental waters is located in the inner room. The samples were preserved in 50% ethylic alcohol or studied soon after their sampling. Before carbon coating and SEM examination, or microanalyses with SEM-associated spectrometers, they were treated in a 33% Chlorox solution and thereafter washed in demineralized water and dried. Micromorphology At low-medium magnification (<20,000), the aspect of coatings varies between caves and, especially, between inner-cave locations. All the described structures are made up of Mn and Fe oxides. In Tremies Cave, coatings of walls from zone B are composed of irregular erected constructions (height : 10s to 100s μm) formed by the aggregation of roughly ovoid primary concretions of about 10 μm (fig. 3). The surface of those primary concretions displays numerous lacunose to reticulate films (pores, about 0.5 μm in diameter, are often subrounded). Remnants of these films and organomorphic corpuscles occur also within the primary concretions (fig. 4). On younger substrates (broken wall exposed since 1970), primary concretions are poorly developed and no prominent construction is visible (fig. 5). In more confined conditions (zone C), the erected constructions of ancient coatings are smaller and less numerous than in zone B but are well individualized (fig. 6). In this zone: C, besides some remnants of lacunose to reticulate films (fig. 7), there is an appearance of filaments and ovoid corpuscles (height/width : 10-30/5-15 μm), which seem to be linked to filaments by a short stalk (fig. 8). In 3 PP Cave, at 25-70 m from entrance, wall coatings present porous heaps of primary concretions (fig. 9). The surface and the inside of the latter comprise remnants of lacunose to reticulate films that evoke those observed in Tremies Cave (fig. 10 and 11). On younger substrates (hard parts of sessile invertebrates), coatings are restricted to micrometric organomorphic corpuscles with some remnants of lacunose or fibrous films (fig. 12). At 100 in from the entrance, coatings are shaped by numerous erected constructions, more or less coalescing (fig. 13). Besides remnants of lacunose films, the primary concretions contain interlacing filaments (diameter : 0.2-0.3 μm) forming cords or veils (fig. 14). In Bagaud Cave, the primary concretions are aggregated in irregular heaps (fig. 15). Lacunose films are particularly frequent and tend to form three-dimensional mamillated structures that were not observed in the other caves (fig. 16). In particular, there is an appearance of tubular structures (fig. 17) and of numerous hemispheroidal structures (diameter : 4-5 μm) with an upper orifice (fig. 18 and 19). At higher magnification (20,000), whatever the cave and inner-cave location, the aspect of oxide deposits is rather smooth or, especially, microgranular (fig. 20). Mineral composition The composition of coatings is different between caves and according to their inner-cave location. In both large caves (Tremies and 3 PP), the Mn/Fe ratio increases with the distance from the cave entrance, i.e. when exchanges with the open sea diminish (fig. 21a). This trend is particularly clear in Tremies Cave, where the confinement gradient is strongly marked. Besides, the Mn/Fe ratio also seems to increase when films are present in the analysed volume (some cubic micrometers) (fig. 21b). In Bagaud Cave, the Mn/Fe ratio reaches high values despite the small size of this cave and its low confinement level. Discussion and conclusions SEM observations suggest that in each studied cave, the Mn-Fe coatings are biosedimentary deposits. Genesis of these deposits is assumed to result mainly from the replacement of biofilms (composed of cells and slime, i.e, of extracellular polymeric substance produced by microorganisms) generated by microbial populations colonizing the cave walls. Considering the darkness of the cave-locations, microbes consist mainly in bacteria, but fungi are probably responsible for the filaments and ovoids corpuscules (evoking sporocysts) occurring in innermost parts. Observations at different scales of the morphological features of oxide deposits reveal a structured organisation which varies along the strong environmental gradients (particularly the confinement level) that occur from the entrance to the innermost parts : erected constructions made up of primary concretions become more and more defined and acquire a pseudo-columnar shape. The aspect of biofilms appears to be controlled by the same environmental parameters. In open or relatively open environments, they frequently show a three-dimensional development (with frequent skullcape-like shapes), while in more confined conditions they exhibit a planar layout. These changes reflect either the adaptation of the slime-producing bacteria to the local trophic resources (correlated to the rate of exchange with the open sea) and water movements, or spatial replacement of taxa. It is assumed that slime (mainly composed of water and exopolysaccharides) induces a local increase of the concentration in dissolved Mn and acts as an ion exchange resin that allows the retention of Mn on the functional groups of EPS. These conditions promote the nucleation of Mn oxide crystallites in the slime. Then. the anionic character of Mn oxides in seawater, and their capacity to catalyse the oxydation of Mn2 to Mn4, allow the process to go on without any other biological intervention; thus, the process of crystal growth becomes possible. In caves where Mn is only supplied by seawater (Tremies and 3 PP), the average value of the Mn/Fe ratio of coatings is negatively correlated to the local availability of nutrients. This trend is probably linked to changes in the selectivity of slimes towards the processes of retention of cations, because this ratio is clearly influenced by the occurrence of biofilms. However, independently from trophic resources, the Mn/Fe ratio can be notably increased when additional Mn is provided by the seeping or flowing of continental waters (Bagaud Cave)
The subterranean environment of Christmas Island is diverse and includes freshwater, marine, anchialine, and terrestrial habitats. The cave fauna comprises swiftlets, and a diverse assemblage of invertebrates, both terrestrial and aquatic, which includes a number of rare and endemic species of high conservation signicance. At least twelve species are probably restricted to subterranean habitats and are endemic to Christmas Island. Previously poorly known, the cave fauna of Christmas Island is a signicant component of the island's biodiversity, and a signicant cave fauna province in an international context. The cave fauna and habitats are sensitive to disturbance from a number of threatening processes, including pollution, deforestation, mining, feral species and human visitors.
In 1998-1999 The Nature Conservancy conducted a bioinventory of caves in Monroe and St. Clair counties in southwestern Illinois. This karst area comprises a small section of the Ozark Plateau isolated from the Missouri Ozarks by the Mississippi River. In the 71 sites that were sampled, 41 species thought to be globally rare were found and were assigned state (S) and global (G) ranks of rarity for conservation use. The list includes 10 species considered to be new to science and 12 species previously unreported from Illinois. Twenty four taxa were classified as obligate subterranean species, including four endemic species: the pseudoscorpion Mundochthonius cavernicolus, the amphipod Gammarus acherondytes, the milliped Chaetaspis sp. (undescribed), and the dipluran Eumesocampa sp. (undescribed). Gammarus acherondytes, recently listed as an endangered species, was found in six previously unsampled caves. All sites were rank-ordered according to the number of global and state rare species. The greatest single site diversity was found in Fogelpole Cave with 18 global and 20 state rare species. The highest subterranean drainage system diversity was found in the Danes/Pautler Cave System with 20 globally rare species. Fogelpole Cave also had the highest number of troglobites with 14 species. The Danes/Pautler Cave System again had the highest number of troglobites found in a groundwater system with 16 species.
The Lithuanian karst region covers about 1000 km(3) in the northern part of the country. This is the most vulnerable area from a pollution point of view. The structure of the total dissolved solids (TDS) shows that the flow of rivers in the karst region is from hydraulically interconnected aquifers. For the last decade (1991-2000) TDS has varied considerably, from 529 to 732 mg/l. The predominant sources of nitrogen and phosphorus within the headwaters of the monitored rivers were diffuse and agricultural in nature. Downstream from the towns nitrogen and especially phosphorus showed both diffuse and point source signals. Contributions of point sources to the stream pollution by nutrients prevail. The time series of monthly dissolved oxygen (O-2) in the main karst region river - the Musa - shows the existence of multiplicative seasonality. The trend cycle (1991-1999) shows low levels of dissolved oxygen in 1991-1993, with a similar fluctuation in 1994, 1995 and 1996 (due to point pollution from the town of Siauliai) and a gradually improving situation since 1997. The general multiplicative trend of dissolved oxygen in the lower reaches of the Musa river (near the border with Latvia) is decreasing (within the accuracy limits). The abundance and species of zoo benthos are suitable criteria (biotic index - 131) for evaluation of a river's biological water quality. Zoo benthos demonstrates tolerances that vary among species, the oxygen regime and the pollution with nitrogen. The best living conditions for invertebrates are in the riverhead of the karst region rivers - 131 = 5.62-6.74 (1991-1999), where pollution with nutrients is caused mostly by agricultural activity. Rare and asynchronous data of biological water quality shows up tendencies that invertebrates prefer less contaminated reaches of rivers
Tropical caves of southeast Asia are often home to a wide range of cave fauna, ranging from microscopic invertebrates through to snakes and bats at the top of the food chain.. This food chain is dependant on the bats. Larger mammals, such as porcupine, goats and elephants may visit caves for shelter or food. Animals such as bats are useful to man, whilst the nests of cave swiftlets are harvested and fetch high prices on the market. Studies on cave fauna began at the end of the 19th century in Malaysia and Thailand.
A total of 13 ceiling drips in Organ Cave, West Virginia, USA, were sampled for fauna for three consecutive 10 day intervals. A total of 444 individuals from 10 copepod genera were found. Incidence functions revealed that 90 percent of the genera were found in eight samples, and that estimates of total diversity indicated only one or two genera had yet to be found. The overall rate of false negatives for different drips was 0.39 and the overall rate for different time intervals was 0.31, also suggesting that the sampling scheme was sufficient. Compared to nearby pools which serve as collection points for epikarst water, the drip samples were significantly different and more diverse. In addition to copepods, a wide variety of other invertebrates were found in drips, including many terrestrial insects that serve as part of the food base for the cave community. Direct sampling of drips is the preferred method at present for sampling the epikarst fauna.
The present contribution deals with aquatic fauna of the Pivka intermittent lakes. Due to their intermittent character some interesting crustaceans from the groups of fairy shrimps (Anostraca), water fleas (Cladocera) and copepods (Copepoda) are found there. Petelinjsko jezero is the only known location in the world for the endemic species Chirocephalus croaticus. Copepod species Diaptomus cyaneus and Diacyclops charon are relatively abundant in Europe, but Petelinjsko jezero and Veliko Drskovško jezero are the only two locations known in Slovenia for both species. All the species are threatened due to destruction of their natural habitats.
The subterranean amphipod crustacean Niphargus aquilex Schiödte is reported from Anglesey, Wales, for the first time. This record extends its known range in Britain and is farthest into the area covered by the Devensian ice, possibly supporting the theory that subterranean aquatic invertebrates survived within the glaciated area. The groundwater-inhabiting diving beetles Hydroporus longulus Mulsant & Rey and H. ferrugineus Stephens (Dytiscidae) were found at the same site, the first records of these species from Anglesey.
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