The karstic cave Križna jama in the South Western part of Slovenia is one of the largest, well known and most beautiful Slovene water caves. The cave consists of more than 8 km of corridors with ...impressive halls, colossal dripstone formations, a subterranean river and numerous lakes. Considering the subterranean fauna, Križna jama has been identified amongst the richest caves in the world. So far, 60 troglobionts, the obligate subterranean species among them 32 aquatic and 28 terrestrial taxa have been recorded and documented. Križna jama has scientific importance, as well as ten subterranean taxa, which have been described based on specimens from this cave. Despite Križna jama is relatively well-studied, new recent unexpected findings are promising. Thus, further discoveries of specialized subterranean species in the cave are expected.
V ekološki študiji smo obravnavali sestav favne na dnu kraškega vodotoka, klasificiran po načinu prehranjevanja. Od izvira proti ponoru reke se je delež suspenziofagov, filtratorjev in drobilcev ...zniževal, naraščal pa je delež detritivorov in strgačev. Delež plenilcev je bil na vseh vzorčnih mestih približno enak. Biološke raziskave so pokazale, da v reki Reki poteka optimalen prehranjevalni pretok z rahlo povečano trofično aktivnostjo, ki se ne odraža negativno v sestavi združbe velikih nevretenčarjev. 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.
Za raziskavo epikraške favne so bili v Zahodni Virginiji v 17 jamah pobrani vzorci iz curkov ter luž napolnjenih s preniklo vodo. V lužah je bilo ugotovljenih 20 rodov ceponožcev, med njimi 11 ...harpaktikoidov in 9 ciklopoidov. Za razumevanje strukturnih ter fizikalnih in kemijskih lastnosti epikrasa je bil poudarek na raziskavi epikraške favne v curkih prenikajoče vode. Izbrana so bila tri vzorčna mesta v Organ jamskem sistemu: Lipps, Sively 2 in Sively 3. V curkih je bilo najdenih 13 rodov ceponožcev, med njimi 8 harpaktikoidov in 5 ciklopoidov. Epikraška favna si je med bližnji curki bolj podobna, kot favna med oddaljenimi curki. Epikraška favna bo pomemben prispevk k pestrosti podzemeljske favne v jamah Apalačev, kot tudi k biodiverziteti ameriške favne. Drip pools and trickles of percolation water in 17 caves in West Virginia were sampled for epikarstic species. A total of 20 genera of copepods were found. 11 different genera of harpacticoids and 9 of cyclopoids were recognized in the samples collected from pools. For understanding of the structure and physico-chemistry of epikarst, the focus was specially on trickles rather than pools. Three sampling sites of the Organ cave system were chosen: the Lipps, Sively 2 and Sively 3 streams. All together in drips 13 genera of copepods, from which 8 of harpacticoids and 5 of cyclopoids have been found. Nearby drips have more similar fauna composition than distant drips. The epikarstic fauna will add significantly to the overall species richness found in Appalachian caves, and likely elsewhere in the U.S. as well.
The decomposition of diversity into within site (α) and between site (β) components is especially interesting in subterranean communities because of their isolated nature and limited dispersal ...potential The aquatic epikarst fauna, sampled from water drips in caves affords a unique opportunity to provide comparable, quantitative samples of a portion of the obligate subterranean dwelling fauna in multiple hierarchical levels. We focused on three interrelated questions-(1) what is the spatial pattern of epikarst species diversity; (2) how does species diversity partition between local, and regional components (nested and replacement); and (3) whether epikarst hotspots are subterranean hotspots in general. We analyzed the geographic pattern of species richness of 30 species of obligate subterranean copepods found in 81 drips in Slovenian caves in three karst regions-Alpine, Dinaric, and Isolated. Comparison of Chao1 and observed (Mao-tau) estimates of species richness indicated sampling in most drips was complete, but species accumulation curves indicated roughly half of the sites in the Dinaric karst had not reached an asymptote. Overall, within drip diversity accounted for three species, different drips in a cave another three, different caves in a region six species, and different regions accounted for the remaining 18 species. Sites in the Dinaric karst had much higher species richness than the other sites, which is in agreement with studies of other components of the subterranean fauna. The fauna associated with drips in Županova jama (jama = cave), in the east-central Dinaric karst was the richest found. While turnover explained the majority of β-diversity, nestedness in the form of hotspot drips was important as well. A consequence is that a small number of drips largely determine cave and regional species diversity.
Since the start of mass production of plastic materials more than a century ago, the problem of accumulating plastic waste in the environment has reached epic proportions. Recently, the problem of ...smaller plastic particles (microplastic, MP) in the environment has become a widely studied topic, but the amount and types of MP in karst environments are still poorly known. Thus, the objective of this study was to collect and analyse samples from various karst habitats and to try and determine the scope of pollution in karst springs that are in part used as sources for drinking water. Of the potential pollution sources, we sampled rainwater, two discharges from wastewater treatment plants, and a leachate from a landfill. We conducted polymer analyses of potential MP particles using FTIR-ATR. The results showed that eight samples from the Postojna region (Postojna–Planina Cave System, rainfall sample and surface streams) contain up to 444 MP particles per m3. However, 32 samples taken from the Škocjan–Kačna–Jama 1 v Kanjaducah Cave System contain up to 60,000 MP particles per m3, with the bulk of particles found in the sediment samples from Škocjan Caves – Kačna Cave System. Samples from Postojna region contained mostly PET, PU and PA polymers, with a minor inclusion of polymers of plastic sponge used for cleaning. Samples from Škocjan region contained mostly PP, PET and PE polymers, with some of PA and PU polymers. Sediment samples contained much less MP particles compared to water samples, which indicates fast transport through karst aquifer.
Prispevek opisuje vodno favno presihajočih Pivških jezer. Zaradi presihajočega značaja jezer so bili na tem območju najdeni zanimivi predstavniki nižjih rakov, predvsem iz skupin škrgonožcev ...(Anostraca), vodnih bolh(Cladocera) ter ceponožcev (Copepoda). Petelinjsko jezero je edini kraj na svetu, kjer še lahko najdemo endemne rakce vrste Chirocephalus croaticus. Vrsti ceponožnih rakov Diaptomus cyaneus in Diacyclops Charon sta relativno pogosti vrsti v Evropi, vendar sta Petelinjsko in Veliko Drskovško jezero v Sloveniji trenutno edini znani nahajališči obeh vrst. Vrste so ogrožene zaradi uničevanja njihovih naravnih habitatov. 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 study of subterranean life in general and cave life in particular has been given several names, most especially biospeleology and speleobiology. Historically, biospeleology came first, and ...signalled that biological study was part of speleology, the science of caves. Speleology itself has come to have several meanings beyond the science of caves, but as a discipline it has not fully developed. Speleobiology emphasizes the connection with biology, especially ecology and evolutionary biology. Biospeleology can be construed as the taxonomic and distributional aspects of the biology of caves while speleobiology can be construed as the aspects pertaining to general biological principles such as evolution.
Hourly temperature was measured for approximately one year at 17 stations in three caves in Quintana Roo, Mexico. Thirteen of these stations were in the extensive twilight zones of all three caves. ...All seventeen stations showed seasonality in temperature with a 3°C drop during the Nortes season. Two of the caves, Muévelo Sabrosito and Muévelo Rico, showed greater variability during the winter months while in Río Secreto (Tuch) variability was greatest during the rainy season. Río Secreto is less open to the surface than the other two. All sites also showed a daily temperature cycle, although it was very faint in some Río Secreto (Tuch) sites. While temperature variability is diminished relative to surface variation, its temporal pattern is worthy of further study.
Relative humidity (RH) was measured at hourly intervals for approximately one year in two caves at seven stations near Playa del Carmen in Quintana Roo, Mexico. Sistema Muévelo Rico is a 1.1 km long ...cave with 12 entrances and almost no dark zone. Río Secreto (Tuch) is a large river cave with more than 40 km of passages, and an extensive dark zone. Given the need for cave specialists to adapt to saturated humidity, presumably by cuticular thinning, the major stress of RH would be its deviation from saturation. RH in Río Secreto (Tuch) was invariant at three sites and displayed short deviations from 100% RH at the other four sites. These deviations were concentrated at the end of the nortes and beginning of the rainy season. Three of the sites in Sistema Muévelo Rico showed a similar pattern although the timing of the deviations from 100% RH was somewhat displaced. Four sites in Sistema Muévelo Rico were more variable, and were analyzed using a measure of amount of time of deviation from 100% RH for each 24 hour period. Strong seasonality was evident but, remarkably, periods of constant high humidity were not the same at all sites. In most Sistema Muévelo Rico sites, there was a detectable 24 hour cycle in RH, although it was quite weak in about half of them. For Río Secreto (Tuch) only one site showed any sign of a 24 hour cycle. The troglomorphic fauna was more or less uniformly spread throughout the caves and did not concentrate in any one area or set of RH conditions. Compared to temperature, RH is much more constant, perhaps even more constant than the amount of light. However, changes in RH as a result of global warming may have a major negative effect on the subterranean fauna.
Throughout the evolutionary tree, there are gains and losses of morphological features, physiological processes, and behavioral patterns. Losses are perhaps nowhere so prominent as for subterranean ...organisms, which typically show reductions or losses of eyes and pigment. These losses seem easy to explain without recourse to natural selection. Its most modern form is the accumulation of selectively neutral, structurally reducing mutations. Selectionist explanations include direct selection, often involving metabolic efficiency in resource poor subterranean environments, and pleiotropy, where genes affecting eyes and pigment have other effects, such as increasing extra-optic sensory structures. This dichotomy echoes the debate in evolutionary biology in general about the sufficiency of natural selection as an explanation of evolution, e.g., Kimura’s neutral mutation theory. Tests of the two hypotheses have largely been one-sided, with data supporting that one or the other processes is occurring. While these tests have utilized a variety of subterranean organisms, the Mexican cavefish,
Astyanax mexicanus
, which has eyed extant ancestral-like surface fish conspecifics, is easily bred in the lab, and whose whole genome has been sequenced, is the favored experimental organism. However, with few exceptions, tests for selection versus neutral mutations contain limitations or flaws. Notably, these tests are often one sided, testing for the presence of one or the other process. In fact, it is most likely that both processes occur and make a significant contribution to the two most studied traits in cave evolution: eye and pigment reduction. Furthermore, narrow focus on neutral mutation hypothesis versus selection to explain cave-evolved traits often fails, at least in the simplest forms of these hypotheses, to account for aspects that are likely essential for understanding cave evolution: migration or epigenetic effects. Further, epigenetic effects and phenotypic plasticity have been demonstrated to play an important role in cave evolution in recent studies. Phenotypic plasticity does not by itself result in genetic change of course, but plasticity can reveal cryptic genetic variation which then selection can act on. These processes may result in a radical change in our thinking about evolution of subterranean life, especially the speed with which it may occur. Thus, perhaps it is better to ask what role the interaction of genes and environment plays, in addition to natural selection and neutral mutation.
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