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1
GAO, YAN, ILAN BEN-YAACOV, UMESH MISHRA, and EVELYN HU. "ETCHED APERTURE GaN CAVET THROUGH PHOTOELECTROCHEMICAL WET ETCHING." International Journal of High Speed Electronics and Systems 14, no. 01 (March 2004): 245–64. http://dx.doi.org/10.1142/s0129156404002326.
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We describe the fabrication of the CAVET (Current Aperture Vertical Electron Transistor) by Photoelectrochemical (PEC) formation of a current aperture. Etch process is quite naturally critical to the achievement of the etched aperture in CAVET. We provide some background on that etch process, and the subsequent modification and optimization of the process for CAVET fabrication.
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Kotzea, Simon, Wiebke Witte, Birte-Julia Godejohann, Mathias Marx, Michael Heuken, Holger Kalisch, Rolf Aidam, and Andrei Vescan. "Comparison of MOCVD and MBE Regrowth for CAVET Fabrication." Electronics 8, no. 4 (March 28, 2019): 377. http://dx.doi.org/10.3390/electronics8040377.
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In this paper, we demonstrate the fabrication of current aperture vertical electron transistors (CAVET) realized with two different epitaxial growth methods. Templates with a p-GaN current blocking layer (CBL) were deposited by metal organic chemical vapor deposition (MOCVD). Channel and barrier layers were then regrown by either molecular beam epitaxy (MBE) or MOCVD. Scanning electron microscope (SEM) images and atomic force microscope (AFM) height profiles are used to identify the different regrowth mechanisms. We show that an AlN interlayer below the channel layer was able to reduce Mg diffusion during the high temperature MOCVD regrowth process. For the low-temperature MBE regrowth, Mg diffusion was successfully suppressed. CAVET were realized on the various samples. The devices suffer from high leakage currents, thus further regrowth optimization is needed.
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Yu, Qingyan, Qi Wang, Pengcheng Liu, Jing Zhang, Qi Zhang, Xiaojuan Deng, and Kai Feng. "Theoretical Study and Application of Rate Transient Analysis on Complex Fractured-Caved Carbonate Reservoirs." Geofluids 2021 (January 23, 2021): 1–15. http://dx.doi.org/10.1155/2021/6611957.
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Carbonate reservoirs are mainly fractured-caved reservoirs with very well-developed dissolved pores, fractures, and caves. They have strong heterogeneity with various types of reservoir pore spaces. Using seismic inversion and reservoir static characterization, the result shows that the fractured-caved carbonate rocks in China are mainly caves with poor connectivity and complex oil-water distribution. Large-scale dissolved caves are mostly discrete and isolated, while the fractures are complex and various. The fracture features are observed either as a single large fractures or as a local fracture network. The characteristics of fluid flow in fracture-caved reservoirs vary as a result of the different combinations of fractures and caves. Currently, the static characterization technology of fractured-caved reservoirs is influenced by the limited resolution of seismic data, leading to large interpretation errors. In contrast, the dynamic method is a more reliable and effective method to determine reservoir parameters. However, traditional seepage equations cannot accurately characterize the flow pattern of fractured-caved carbonate reservoirs. In the case of a single large-scale dissolved fractured-caved reservoir, oil wells are usually connected to large caves through large fractures or directly drilled into large dissolved caves. In this study, the large-scale dissolved caved reservoir is simplified into two cases: (1) a single-cave and single-fracture series model composed of a single-cave and a single-fracture and (2) a composite model of dissolved caves and surrounding fracture networks. Note that the flow in a large cave is considered as free flow due to its large scale. The flow in a large fracture connected to the cave is considered as flow through porous media, and the flow in the reservoir surrounding the fracture network is considered as multiple-porosity model seepage flow. The corresponding seepage-free flow coupling mathematical model of different fractured-caved reservoirs has been established on this basis. We also obtained the rate transient analysis type curves of the oil well, conducted sensitivity analysis of each parameter, constructed the corresponding rate transient analysis curves, analyzed sensitivities of each parameter, and finally designed a dynamic evaluation method of well and reservoir parameters for different types of fractured-caved carbonate reservoirs. This study extensively applies this method in the Halahatang Oilfield of China and evaluates parameters such as reservoir reserves and physical properties to provide rational guidance for developing fractured-caved carbonate reservoirs.
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Verma, Sumit, M. Saqib Akhoon, Sajad A. Loan, and Mana Al Reshan. "A normally OFF GaN CAVET and its thermal and trap analysis." Journal of Computational Electronics 18, no. 3 (June 21, 2019): 941–50. http://dx.doi.org/10.1007/s10825-019-01360-0.
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Ji, Dong, Matthew A. Laurent, Anchal Agarwal, Wenwen Li, Saptarshi Mandal, Stacia Keller, and Srabanti Chowdhury. "Normally OFF Trench CAVET With Active Mg-Doped GaN as Current Blocking Layer." IEEE Transactions on Electron Devices 64, no. 3 (March 2017): 805–8. http://dx.doi.org/10.1109/ted.2016.2632150.
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Liang, Yan, Chao Liu, Tong Lu Li, and Ping Li. "The Effect of the Filling Caves on Loess Slope Stability in Irrigation." Advanced Materials Research 753-755 (August 2013): 648–52. http://dx.doi.org/10.4028/www.scientific.net/amr.753-755.648.
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Landslides are serious geological disasters in loess areas. In order to study the effect of the filling caves in the edge of loess tableland on loess slope stability, the slope stability of sliding from the caves was calculated in irrigation when caves were filled with compacted soil, lime soil, lime-ash soil and non-filled. The results show when caves are filled with lime soil the slope stability is the highest. The effects of variability of the physical and mechanical property indexes of caver filler on loess slope stability were researched further. The results show that (1) the variation coefficients of unit weigh and the shear strength indexes of cave filler lime soil have small effect on the average value of safety reserve, but have big effect on the standard deviation of safety reserve, which explains that the design risks increase while the variation coefficient increasing. (2) with the increase of variation coefficients of unit weigh and the shear strength indexes of cave filler the failure probability increases. Especially when variation coefficient is bigger than 0.3, the failure probability of loess slope is very sensitive to variation coefficient. (3) the effect of correlation coefficient among unit weight and the shear strength indexes of cave filler on failure probability increases with the variation coefficient increasing. It is very important to guarantee filling project. Good quality of filling construction will decrease the variability of cave filler, heighten the stability of loess slope, and decrease the occurrence of loess disasters.
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Ji, Dong, Yuanzheng Yue, Jianyi Gao, and Srabanti Chowdhury. "Dynamic Modeling and Power Loss Analysis of High-Frequency Power Switches Based on GaN CAVET." IEEE Transactions on Electron Devices 63, no. 10 (October 2016): 4011–17. http://dx.doi.org/10.1109/ted.2016.2601559.
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Gao, Y., I. Ben-Yaacov, U. K. Mishra, and E. L. Hu. "Optimization of AlGaN∕GaN current aperture vertical electron transistor (CAVET) fabricated by photoelectrochemical wet etching." Journal of Applied Physics 96, no. 11 (December 2004): 6925–27. http://dx.doi.org/10.1063/1.1806281.
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Chowdhury, Srabanti, Man Hoi Wong, Brian L. Swenson, and Umesh K. Mishra. "CAVET on Bulk GaN Substrates Achieved With MBE-Regrown AlGaN/GaN Layers to Suppress Dispersion." IEEE Electron Device Letters 33, no. 1 (January 2012): 41–43. http://dx.doi.org/10.1109/led.2011.2173456.
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Chowdhury, Srabanti, Brian L. Swenson, and Umesh K. Mishra. "Enhancement and Depletion Mode AlGaN/GaN CAVET With Mg-Ion-Implanted GaN as Current Blocking Layer." IEEE Electron Device Letters 29, no. 6 (June 2008): 543–45. http://dx.doi.org/10.1109/led.2008.922982.
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PHAM, DINH, MINH NGUYEN, THAI PHAM, PHUC LA, NGA HOANG, CAO PHAN, DANG HAI YEN, and HAO TRAN. "PRELIMINARY STUDY ON INVERTEBRATE BIODIVERSITY OF VOLCANIC CAVES IN KRONG NO, DAK NONG PROVINCE, VIETNAM." LIFE OF THE EARTH 42, no. 4 (November 25, 2020): 406–10. http://dx.doi.org/10.29003/m1769.0514-7468.2020_42_4/406-410.
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Survey on invertebrate biodiversity of volcanic caves in Krong No, Dak Nong province, Vietnam was carried in 2018 and 2019. The survey were done in 8 typical caves are Co cave (475 m long), C1 cave (402 m), C2 cave (402 m), C3 cave (716 m), C4 cave (251 m), C6 cave (180 m), C6.1 cave (293 m) and C7 cave (1066 m). The survey result recorded 41 species, 31 families of 5 classes, 13 orders of invertebrate at volcanic caves in Krong No. It is expected that 13 species will become new taxa, for example a scorpion of the Chaerilidae family, Chaerilus chubluk Lourenco, Tran & Pham, 2020 in the Co cave. The large and long caves with a complicated structure with many corners are more valuable in term of biological diversity than the small caves with a simple structure.
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Mao, Wei, Haiyong Wang, Penghao Shi, Cui Yang, Yantao Zhang, Xuefeng Zheng, Chong Wang, Jincheng Zhang, and Yue Hao. "Study of GaN-based step-doping superjunction CAVET for further improvement of breakdown voltage and specific on-resistance." Semiconductor Science and Technology 33, no. 2 (January 12, 2018): 025005. http://dx.doi.org/10.1088/1361-6641/aaa32a.
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Jacobson, Jeffrey. "Configuring Multiscreen Displays with Existing Computer Equipment." Proceedings of the Human Factors and Ergonomics Society Annual Meeting 46, no. 7 (September 2002): 761–65. http://dx.doi.org/10.1177/154193120204600703.
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An immersive multiscreen display (a UT-Cave) may be assembled from common home/office equipment which can be borrowed in most research settings. The simplest design requires two LCD projectors, three personal computers, the corner of a room, a network hub and cables. The required software is an inexpensive but graphically powerful computer game, Unreal Tournament (UT), and a freeware patch called “CaveUT.” Unreal Tournament is partially open source and supports rapid authoring of visually rich virtual worlds, complex animations, and software modifications such as alternative physics or artificial intelligence. PC-based game hardware and game engines such as the one for UT deliver superior real-time graphics at a tiny fraction of the cost for traditional immersive multiscreen displays, such as the CAVE™. While currently having fewer features, the UT-Cave, like the traditional CAVE-like displays, is useful for research in vehicle simulation, human balance, architectural simulation, novel human-computer interfaces and much more. Except for UT's game engine, which is very inexpensive, everything about the UT-Cave is free and open-source at “ www.planetjeff.net/ut ”. UT-Caves with more screens have been assembled using the same basic design principles illustrated here. A sample experiment is presented which uses a four-screen UT-Cave controlled from the control program, “LabView.”
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Maślak, Magdalena, and Gabriela Barczyk. "Oribatid mites (Acari, Oribatida) in selected caves of the Kraków-Wieluń Upland (southern Poland)." Biological Letters 48, no. 1 (January 1, 2011): 107–16. http://dx.doi.org/10.2478/v10120-011-0011-y.
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Oribatid mites (Acari, Oribatida) in selected caves of the Kraków-Wieluń Upland (southern Poland) This paper describes and compares the species composition and community structure of the oribatid mite fauna of 5 caves in the Kraków-Wieluń Upland (Wyżyna Krakowsko-Wieluńska). We also compare oribatid communities in 3 chosen caves with oribatid communities in the soil and litter (leaves, dead wood, bat guano) in the vicinity of the cave entrances. Three hypotheses were tested: (1) oribatid communities from the soil and litter near the caves differ from the communities inhabiting caves; (2) the composition of oribatid communities depends on cave size; (3) the cave communities strongly depend on microhabitat quality and diversity. We collected 1112 adult oribatids from caves and 838 from the soil and litter near the caves. Oribatid communities in the caves were different from the soil communities. Litter, guano and dead wood were the microhabitats that affected oribatid communities significantly. In the other cave microhabitats (soil and mud), oribatids were infrequent. Cave size affected the oribatid community structure.
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Smith, Lisa M., Terry J. Doonan, Andrea L. Sylvia, and Jeffery A. Gore. "Characteristics of Caves Used by Wintering Bats in a Subtropical Environment." Journal of Fish and Wildlife Management 12, no. 1 (April 13, 2021): 139–50. http://dx.doi.org/10.3996/jfwm-20-078.
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Abstract Many cave-roosting bats are declining in number throughout their range because of multiple threats, including disease, disturbance by humans, and habitat loss. Successful conservation of cave-roosting bats requires an understanding of the roles of microclimate, cave structure, and the surrounding landscape on the distribution and abundance of bats, and in particular, the use of winter cave roosts. Cave bats have been well studied in temperate climates, but we know little about these bats in subtropical climates. From 2015 to 2017, we conducted 399 winter surveys of 162 caves in Florida to evaluate factors affecting the presence and abundance of bats at cave roosts. We also determined whether temperatures at these cave roosts were suitable for Pseudogymnoascus destructans, the fungus that causes white-nose syndrome. Across all 3 y, we detected three species of bats: tricolored bat Perimyotis subflavus in 126 (77.8%) caves, southeastern myotis Myotis austroriparius in 51 (31.5%) caves, and a single Rafinesque's big-eared bat Corynorhinus rafinesquii. We analyzed the presence of both tricolored bats and southeastern myotis in caves by using mixed-effects models with a binomial distribution and the number of tricolored bats by using generalized linear mixed-effects models with a Poisson error distribution. Tricolored bat presence was significantly and positively influenced by a cooler cave surface temperature, larger cave entrance size, a single entrance, and the presence of solution holes. Tricolored bat abundance increased in longer, cooler caves that had solution holes, a single, unobstructed entrance, and had no signs of flooding. Southeastern myotis presence was positively associated with longer, domed caves. To be most effective, conservation efforts in subtropical climates should focus on caves with the identified characteristics. More than 90% of caves surveyed each year had a cave interior surface temperature below the upper critical growth limit for P. destructans (19.8°C), indicating that most Florida caves are suitable for growth of P. destructans. Therefore, regular monitoring of winter bat populations in subtropical caves may be important for detecting P. destructans and white-nose syndrome.
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Bradley, J. Gavin, and Perri K. Eason. "Predation risk and microhabitat selection by cave salamanders, Eurycea lucifuga (Rafinesque, 1822)." Behaviour 155, no. 10-12 (2018): 841–59. http://dx.doi.org/10.1163/1568539x-00003505.
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Abstract Habitat selection is driven by many factors, but no one location is likely to be best for all factors; thus, individuals are subject to trade-offs when selecting habitat. Caves provide a clear example of such trade-offs because these habitats are energy deprived. Cave salamanders (Eurycea lucifuga) commonly inhabit caves at least in part because this habitat is cool and wet. We tested the hypothesis that caves also provide cave salamanders with a reduction in predation risk. We used clay models to test for differences in predation risk in caves vs. forests and at low (e.g., ground) vs. elevated (e.g., cave wall) positions, and recorded locations of cave salamanders to assess vertical (i.e., wall) vs. non-vertical (e.g., ground) substrate selection in a cave. Overall, a mean of 3.2 models in caves were damaged and a mean of 8.2 were damaged in forests. Cave salamanders selected vertical substrate more often than non-vertical substrate (, ), and in caves, low-positioned models were more likely to be damaged than models on walls, although there was no effect of model height in forests. This study suggests that caves provide salamanders a refuge from increased predation pressure, a benefit that likely compensates for the costs of moving between caves and the richer foraging grounds outside them.
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Yang, S., and Y. Shi. "Numerical simulation of formation and preservation of Ningwu ice cave, Shanxi, China." Cryosphere Discussions 9, no. 2 (April 14, 2015): 2367–95. http://dx.doi.org/10.5194/tcd-9-2367-2015.
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Abstract. Ice caves exist in locations where annual average temperature in higher than 0 °C. An example is Ningwu ice cave, Shanxi Province, the largest ice cave in China. In order to quantitatively explain the mechanism of formation and preservation of the ice cave, we use Finite Element Method to simulate the heat transfer process at this ice cave. There are two major control factors. First, there is the seasonal asymmetric heat transfer. Heat is transferred into the ice cave from outside, very inefficiently by conduction in spring, summer and fall. In winter, thermal convection occurs that transfers heat very efficiently out of the ice cave, thus cooling it down. Secondly, ice–water phase change provides a heat barrier for heat transfer into the cave in summer. The calculation also helps to evaluate effects of global warming, tourists, etc. for sustainable development of ice cave as tourism resource. In some other ice caves in China, managers installed air-tight doors at these ice caves entrance intending to "protect" these caves, but this prevent cooling down these caves in winters and these cave ices will entirely melt within tens of years.
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Kurniawan, Isma Dwi, Cahyo Rahmadi, Tiara Esti Ardi, Ridwan Nasrullah, Muhammad Iqbal Willyanto, and Andy Setiabudi. "The Impact of Lampenflora on Cave-dwelling Arthropods in Gunungsewu Karst, Java, Indonesia." Biosaintifika: Journal of Biology & Biology Education 10, no. 2 (August 29, 2018): 275–83. http://dx.doi.org/10.15294/biosaintifika.v10i2.13991.
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The development of wild caves into show caves is required an installation of electric lights along the cave passages for illumination and decoration purposes for tourist attraction. The presence of artificial lights can stimulate the growth of photosynthetic organisms such as lampenflora and alter the typical cave ecosystem. The study was aimed to detect the effect of lampenflora on cave-dwelling arthropods community. Four caves were sampled during the study, 2 caves are show caves with the existence of lampenflora and 2 others are wild caves without lampenflora. Arthropods sampling were conducted by hand collecting, pitfall trap, bait trap and berlese extractor. Lampenflora comprises of algae (Phycophyta), moss (Bryophyta) and fern (Pteridophyta) grow mostly around white light lamps. Richness, diversity, and evenness indices of Arthropods are higher in caves with the existence of lampenflora compared to caves without lampeflora. This study clearly shows that the presence of lampenflora can increase Arthropods diversity and suppress dominancy of common Arthropods species in caves, also increasing the relative abundance of predators. This condition will shift the ecosystem equilibrium and lead to cave ecosystem destruction. The results of this study should be a scientific consideration for show cave development and management. Lampenfloras have to be removed from all caves and preventive efforts should be taken to minimize their growth.
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Xu, Chao, Bangrang Di, and Jianxin Wei. "A physical modeling study of seismic features of karst cave reservoirs in the Tarim Basin, China." GEOPHYSICS 81, no. 1 (January 1, 2016): B31—B41. http://dx.doi.org/10.1190/geo2014-0548.1.
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On seismic migration sections, anomalous bright spots, called the string of beads response (SBR), are common features of carbonate karst reservoirs at the seismic scale in the Tarim Basin, China. To understand the SBR features of different karst caves, which is an important issue for local exploration, we conducted a physical modeling experiment. Within the physical model, we included various single caves with different scales, velocities, shapes, and fluids, as well as multiple caves in different spatial distributions. SBRs of all caves were extracted and summarized from the migration sections. First, we investigated effects of the cave scale, velocity, spatial distribution, shape, and fluids on SBRs. The relative amplitude of SBRs increased with the cave width ranging from 25 to 400 m and decreased with the cave velocity. The SBR split into two new SBRs when the cave height was larger than 100 m. Spatially distributed multiple caves resulted in some special SBRs, such as long SBRs, inclined SBRs, waved SBRs, and chaotic SBRs. The cave shape contribution to SBRs could be neglected in deep strata practically. The relative amplitude of SBRs of caves filled with gas and oil was stronger than those filled with water. Then, we established an interpretation chart of the corresponding relationship between six types of SBRs and their potential caves. Short SBRs were the responses of caves with a height of less than 60 m. Long SBRs corresponded to two kinds of cave units: (1) a single cave with a height between 70 and 100 m and (2) two caves (height less than 60 m) vertically distributed with a small distance (less than 60 m). Chop-shaped SBRs indicated caves with a width of more than 100 m. Inclined SBRs, waved SBRs, and chaotic SBRs corresponded to multiple caves spatially distributed in triangles, rhombuses, and clusters, respectively.
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Zortéa, M., NA Bastos, and TC Acioli. "The bat fauna of the Kararaô and Kararaô Novo caves in the area under the influence of the Belo Monte hydroelectric dam, in Pará, Brazil." Brazilian Journal of Biology 75, no. 3 suppl 1 (August 2015): 168–73. http://dx.doi.org/10.1590/1519-6984.00414bm.
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Abstract Brazil’s large territory displays significant richness in caves with about 12 thousand caves already recorded. Nevertheless, studies on bats in these environments are extremely scarce and fragmented. This study characterized the chiropteran fauna from two sandstone caves under the influence of the Belo Monte hydroelectric dam (Belo Monte UHE) in Pará, Brazil. The Kararaô and Kararaô Novo caves are located on the same ridge, 250 m apart. Three expeditions were carried out in 2013 and 2014, with a 4- to 5-month interval in between. A total of 589 animals were caught, 246 in the Kararaô cave and 343 in the Kararaô Novo cave. Fifteen species were recorded (13 in each cave) representing 79% similarity. With the exception of Vampyrum spectrum, which is not a cave species, the remaining recorded species were mostly cave bat species. Some species seemed to use the caves seasonally, although the basis of this pattern is still unknown. The most commonly observed species were Pteronotus personatus (dominant in the Kararaô cave), P. parnellii (dominant in the Kararaô Novo cave), and Lionycteris spurrelli, which accounted for 65% of all captures recorded for the two caves. Natalus macrourus is a species recorded in the Kararaô cave that is regionally threatened with extinction. Both caves are less than 500 m from the future reservoir; however, because the Kararaô cave entry is in an area that is lower than the reservoir, it can suffer alterations that would affect its dynamics. This raises great concern about the cave’s associated fauna.
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Ji, Dong, Anchal Agarwal, Haoran Li, Wenwen Li, Stacia Keller, and Srabanti Chowdhury. "880 V/ $2.7~\text{m}\Omega\cdot\text{cm}^{\text{2}}$ MIS Gate Trench CAVET on Bulk GaN Substrates." IEEE Electron Device Letters 39, no. 6 (June 2018): 863–65. http://dx.doi.org/10.1109/led.2018.2828844.
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Martí, Ruth, Maria J. Uriz, Enric Ballesteros, and Xavier Turon. "Benthic assemblages in two Mediterranean caves: species diversity and coverage as a function of abiotic parameters and geographic distance." Journal of the Marine Biological Association of the United Kingdom 84, no. 3 (May 24, 2004): 557–72. http://dx.doi.org/10.1017/s0025315404009567h.
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Benthic assemblages of two Mediterranean submarine caves were compared. Species coverage and number of species were lower in internal (dark) communities than external. This feature was specially marked in the less illuminated cave. Ordination analyses performed on species coverage per community for each cave separately, distinguished several benthic communities from the outermost to the innermost zone of each cave. Cluster analyses on species coverage, taking into account all communities in both the caves, established similarities among communities: algal-dominated communities clustered according to the level of light received independently of the cave they inhabited, while animal-dominated communities were more similar within each cave than between the caves. Moreover, among the abiotic parameters measured irradiance was the only factor that clearly diminished from the entrance to the innermost zone in both the caves. In contrast, water movement and particulate organic matter varied differently in each cave. Results indicate that the different topography, depth and geographic location of the two caves determine water movement, light penetration and nutrient availability along the caves. These factors are responsible for determining species abundance and diversity, as well as species growth habit in each community.
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Graybill, Rhiannon, and Peter J. Sabo. "Caves of the Hebrew Bible: A Speleology." Biblical Interpretation 26, no. 1 (February 5, 2018): 1–22. http://dx.doi.org/10.1163/15685152-00261p01.
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This paper engages the five cave narratives of the Hebrew Bible: Lot and his daughters (Genesis 19), the cave of Machpelah (Genesis 23), Joshua and the five Amorite Kings (Joshua 10), Saul and David’s cave encounter (1 Samuel 24), and Elijah’s theophany at Horeb (1 Kings 19). Biblical caves are significant and symbolic places. Frequently, the cave is associated with concealment, providing a hiding place for people and taboo practices and things. The cave is also a space of resistance, both within the text and as part of a larger critique of futurity. Biblical caves are likewise significant to the analysis of gender. While the caves of Genesis simultaneously imitate and displace the female body, other biblical caves are wholly masculine spaces, acting as both shelters and prisons for men. Attending to the caves thus yields insight to questions of gender, futurity, and the function of space in literary reading.
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Reinhart, Hilary, Mohammad Ainul Labib, and Eko Haryono. "Speleogenetic process of Suaran Block, karst of Sangkulirang–Mangkalihat, East Kalimantan." E3S Web of Conferences 200 (2020): 06011. http://dx.doi.org/10.1051/e3sconf/202020006011.
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Karst of Sangkulirang Mangkalihat is one of the greatest karst areas in Indonesia and has hundreds of caves. Some of those caves are located at Suaran Block, one of the main karst block at this karst. This paper aims to study the speleogenesis process, as the fundamental process on karst landscape and cave development in that area. Speleogenetic process can be examined from the shape of the cave passage using uniformitarianism approach. That principle creates speleomorphology as the study of cave passage form and the factors that affect it. The examination of the cave passages uses cave maps to see the form and direction of them. As the result, caves at Suaran Block are formed mainly driven by geological structures such as fault – fissures and bedding plane which is indicated by linear form of the cave passage and water flow which shows sinusoidal form of the cave passage. Some caves are shaped by the combination of geological structure and water flows make them have mixed-induced speleogenesis.
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Souza Silva, Marconi, Luiz Felipe Moretti Iniesta, and Rodrigo Lopes Ferreira. "Invertebrates diversity in mountain Neotropical quartzite caves: which factors can influence the composition, richness, and distribution of the cave communities?" Subterranean Biology 33 (February 13, 2020): 23–43. http://dx.doi.org/10.3897/subtbiol.33.46444.
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Twenty caves located in a high altitudinal quartzite area in Brazil were examined for invertebrate richness and composition and in terms of environmental factors that determine community structure. We evaluate how distance, altitude, cave extension, environmental stability, number and size of cave entrances and stream presence can act on species composition and richness. The caves presented a high richness of troglophilic (463 spp.) and troglobitic species (6 spp.) in relation to other siliciclastic caves around the world. The average richness was 39.55 species per cave (sd = 21.87), the quantitative similarity among caves was 41% and turnover was βrepl. = 0.769. Araneae (20% of the sampled species), Diptera (18%) and Coleoptera (14%) were the dominant orders regarding species richness. Only twenty percent of the caves were placed out of the confidence interval of the average taxonomic distinctness (∆+); however, the ∆+ decreased with the increase of environmental stability. Cave extension and stream presence were the main factors determining the variation of species composition among caves. Cave extension also influenced species richness variations. Furthermore, the total richness and richness of troglobitic species increased with cave extension. The threats to these habitats further revealed that the fauna is at risk due to tourism, trampling and natural soil erosion that can promote microhabitat alterations. Therefore, quartzite caves also require special attention regarding conservation actions in order to keep their natural biological dynamics.
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Plăiaşu, Rodica, Arpat Ozgul, Benedikt R. Schmidt, and Raluca I. Băncilă. "Estimation of apparent survival probability of the harvestman Paranemastoma sillii sillii (Herman, 1871) from two caves." Animal Biology 67, no. 2 (2017): 165–76. http://dx.doi.org/10.1163/15707563-00002529.
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Reliable estimates of population parameters are lacking for most cave-dwelling species. This lack of knowledge may hinder the appropriate management of caves and populations of cave-dwelling species. Using monthly capture-recapture data and Cormack-Jolly-Seber models, we (i) estimated the apparent survival of individuals in two cave populations of the harvestman Paranemastoma sillii sillii (Herman, 1871) from the Mehedinti Mountains in south-western Romania; (ii) investigated temporal variation in apparent survival; (iii) tested if surface weather conditions affect apparent survival of cave-dwelling harvestmen through their influence upon cave environmental conditions and (iv) tested for sex differences in apparent survival. Our results show that the apparent monthly survival estimates were high for both studied cave populations and there was a significant sex effect on survival. Males had lower survival than females, and the survival difference between caves was larger in males than in females. Temporal (i.e., monthly) variation in apparent survival was low and the weather conditions at the surface had little influence on apparent survival as the environment inside the caves is well buffered against weather fluctuations outside the caves. Our results indicate that caves stabilize survival of facultative cave-dwelling species and may serve as microrefugia for epigean species. We suggest that caves should be considered for conservation because they may serve as a refuge for some epigean species during harsh weather conditions.
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Waring, Chris, Stuart Hankin, Stephen Solomon, Stephen Long, Andrew Yule, Robert Blackley, Sylvester Werczynski, and Andrew Baker. "Cave radon exposure, dose, dynamics and mitigation." Journal of Cave and Karst Studies 83, no. 1 (March 18, 2021): 1–19. http://dx.doi.org/10.4311/2019es0124.
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Many caves around the world have very high concentrations of naturally occurring 222Rn that may vary dramatically with seasonal and diurnal patterns. For most caves with a variable seasonal or diurnal pattern, 222Rn concentration is driven by bi-directional convective ventilation, which responds to external temperature contrast with cave temperature. Cavers and cave workers exposed to high 222Rn have an increased risk of contracting lung cancer. The International Commission on Radiological Protection (ICRP) has re-evaluated its estimates of lung cancer risk from inhalation of radon progeny (ICRP 115) and for cave workers the risk may now (ICRP 137) be 4–6 times higher than previously recognized. Cave Guides working underground in caves with annual average 222Rn activity > 1,000 Bq/m3 and default ICRP assumptions (2,000 workplace hours per year, equilibrium factor F = 0.4, dose conversion factor DCF = 14 µSv/(kBq h m-3) could now receive a dose of > 20 mSv/y. Using multiple gas tracers (d13 C--CO2, Rn and N2O), linked weather, source gas flux chambers, and convective air flow measurements a previous study unequivocally identified the external soil above Chifley Cave as the source of cave 222Rn. If the source of 222Rn is external to the cave, a strategy to lower cave 222Rn by passively decreasing summer pattern convective ventilation, which draws 222Rn into caves, is possible without harming the cave environment. A small net annual average temperature difference (warmer cave air) due to geothermal heat flux produces a large net annual volumetric air flow bias (2–5:1) favoring a winter ventilation pattern that flushes Rn from caves with ambient air. Rapid anthropogenic climate change over decades may heat the average annual external temperature relative to the cave temperature that is stabilized by the thermal inertia of the large rock mass. Relative external temperature increases due to climate change (Jenolan Caves, 2008–2018, 0.17°C) reduces the winter pattern air flow bias and increases Rn concentration in caves.
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Yang, S., and Y. Shi. "Numerical simulation of formation and preservation of Ningwu ice cave, Shanxi, China." Cryosphere 9, no. 5 (October 22, 2015): 1983–93. http://dx.doi.org/10.5194/tc-9-1983-2015.
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Abstract. Ice caves exist in locations where annual average air temperature is higher than 0 °C. An example is Ningwu ice cave, Shanxi Province, the largest ice cave in China. In order to quantitatively investigate the mechanism of formation and preservation of the ice cave, we use the finite-element method to simulate the heat transfer process at this ice cave. There are two major control factors. First, there is the seasonal asymmetric heat transfer. Heat is transferred into the ice cave from outside very inefficiently by conduction in spring, summer and fall. In winter, thermal convection occurs that transfers heat very efficiently out of the ice cave, thus cooling it down. Secondly, ice–water phase change provides a heat barrier for heat transfer into the cave in summer. The calculation also helps to evaluate effects of global warming, tourists, colored lights, climatic conditions, etc. for sustainable development of the ice cave as a tourism resource. In some other ice caves in China, managers have installed airtight doors at these ice caves' entrances with the intention of "protecting" these caves, but this in fact prevents cooling in winter and these cave ices will entirely melt within tens of years.
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Gavish-Regev, Efrat, Shlomi Aharon, Igor Armiach Steinpress, Merav Seifan, and Yael Lubin. "A Primer on Spider Assemblages in Levantine Caves: The Neglected Subterranean Habitats of the Levant—A Biodiversity Mine." Diversity 13, no. 5 (April 23, 2021): 179. http://dx.doi.org/10.3390/d13050179.
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Caves share unique conditions that have led to convergent adaptations of cave-dwelling animals. In addition, local factors act as filters on regional species-pools to shape the assemblage composition of local caves. Surveys of 35 Levantine caves, distributed along a climate gradient from the mesic in the north of Israel to hyper-arid areas in the south of Israel, were conducted to test the effect of cave characteristics, location, climate, bat presence, and guano level on the spider assemblage. We found 62 spider species and assigned four species as troglobites, 28 as troglophiles, and 30 as accidentals. Precipitation, elevation, latitude, minimum temperature, and guano levels significantly affected the composition of cave-dwelling spider assemblages. Caves situated in the Mediterranean region had higher species richness and abundance, as well as more troglobite and troglophile arachnids. These discoveries contribute to the knowledge of the local arachnofauna and are important for the conservation of cave ecosystems. By comparing spider assemblages of Levantine caves to European caves, we identified gaps in the taxonomic research, focusing our efforts on spider families that may have additional cryptic or yet to be described cave-dwelling spider species. Our faunistic surveys are crucial stages for understanding the evolutionary and ecological mechanisms of arachnid speciation in Levantine caves.
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Alexandrowicz, Zofia, Jan Urban, and Viacheslav Andreychouk. "Crystal Caves in the ‘Wieliczka’ Salt Mine – unique cave site." Zeitschrift für Geomorphologie, Supplementary Issues 62, no. 3 (March 12, 2021): 235–54. http://dx.doi.org/10.1127/zfg_suppl/2021/0696.
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Dhamorikar, Amruta, Dhanusha Kawalkar, and Shirish Manchi. "Distribution of crickets (Subfamily: Phalangopsinae) in caves of Baratang Island, Andaman and Nicobar Islands, India." International Journal of Speleology 49, no. 3 (September 2020): 221–28. http://dx.doi.org/10.5038/1827-806x.49.3.2341.
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Cave-dwelling organisms share different ecological and evolutionary relationships with caves. Based on these interactions, they are categorized as troglobites, troglophiles, and trogloxenes. In India, caves are meagerly explored, and thus cave study is in its infancy in India. Through the present study, we attempted to understand and model the distribution of crickets (Family Phalangopsidae), a critical group of insects - being the primary consumers in the cave ecosystems. We sampled seven caves using belt transects (N = 184; total area covered = 1294.9 m2) with 1 m width. During the survey, we encountered 818 individual crickets (116.85 ± 47.16 SD per cave). Of these, 87.7% encounters were on walls, 7.09% were on the ceiling, and 5.13% were on the cave floor. We used the Single-species Multi-season occupancy model to calculate the overall, zone-wise, and cave-specific occupancy. Cricket occupancy in Baratang caves is seasonal and highly zonal, with detectability ≤1. The cave with less distinct zones has more consistent occupancies and zero chances of extinction and colonization. Hence, these caves serve as suitable habitat for the source population. A negative correlation of cave morphometric features (cave volume, wall surface area, and floor surface area), and density of crickets (p < 0.05), might need further validation. The study shows the need for detailed studies regarding cricket taxonomy and ecology towards establishing the conservation importance of the species and their habitat in the islands.
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Gomell, Annika, Daniel Austin, Marc Ohms, and Andreas Pflitsch. "Air pressure propagation through Wind Cave and Jewel Cave: How do pressure waves travel through barometric caves?" International Journal of Speleology 50, no. 3 (September 2021): 263–73. http://dx.doi.org/10.5038/1827-806x.50.3.2393.
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In barometric caves, air pressure gradients between the outside atmosphere and the cave induce strong bidirectional compensating currents, which control almost all elements of speleoclimatology, including air temperature, humidity, and CO2 dynamics. Therefore, this study set out to investigate air pressure propagation through Wind Cave and Jewel Cave – two major barometric cave systems in the Black Hills of South Dakota, USA. Based on high-resolution air pressure data from both the surface and several measurement sites inside the caves, four systematic changes of pressure waves during their journey through the caves and their related speleoclimatological processes were identified and discussed: Compared to the outside atmosphere, the pressure signals within Wind Cave and Jewel Cave showed (1) an absolute displacement due to different altitudes of the measuring sites, (2) a delay related to the travel times of the pressure wave to the measuring sites, (3) a smoothing effect, and (4) a damping effect due to long response times of the caves to external pressure changes. The spatial distribution of the changes observed in this study shows that for Wind Cave, the cave opening and the narrow entrance area represent the main obstacle for pressure propagation, while for Jewel Cave, the deep areas have the greatest influence on the development of air pressure gradients. Our analyses provide completely new insights into the processes and mechanisms inside barometric caves, which will significantly contribute to the understanding of pressure-related airflow dynamics and all related elements of speleoclimatology.
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Raji, Ramat Onyeneoyiza, Oluwafemi Adebayo Oyewole, Omeiza Haruna Ibrahim, Yetunde Noimot Tijani, and Mordecai Gana. "Microbial communities and activities in caves." Brazilian Journal of Biological Sciences 6, no. 14 (2019): 557–64. http://dx.doi.org/10.21472/bjbs.061407.
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Caves are natural aperture and oligotrophic extreme environment for psychrophilic and psychrotolerant microorganisms. Microorganisms found in caves can be indigenous to the caves or introduced by humans, animals, water flow and wind action. Group of microorganisms found in caves are bacteria, fungi, protozoa, algae and viruses. However, bacteria and fungi are the dominant microorganisms. Cave microorganisms are metabolically diverse and are able to acquire energy independently through photoautotrophic, chemoautotrophic or heterotrophic activities. Different microbial groups also interact in the formation of cave and as part of the biogeochemical cycling of elements. Cave microbiology has allowed the detection of microorganisms with the potentials to produce different biomolecules for industrial, pharmaceutical, environmental and biotechnological purposes.
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Gurgen, Gurcan. "Caves and cave art." New Trends and Issues Proceedings on Humanities and Social Sciences 6, no. 4 (September 24, 2019): 100–105. http://dx.doi.org/10.18844/prosoc.v6i4.4403.
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This paper aims to discuss the impact and importance of the karstic caves, which are effective on the emergence and development of cave art and the rocks that generate them. The origin of cave traces to 40 thousand years and the creation of many more works of art and the importance of the rocks to the present day is very important. In particular, carbonate rocks such as limestone and marble became important spaces and raw materials in terms of art history and development. Carbonate deposits placed in the large ocean bowls during geological periods have been elevated and altered land during orogenesis periods. The fact that the carbonate rocks are soluble due to environmental conditions has led to the formation of a large number of caves depending on the size and distribution of the masses forming them. These karstic caves, which constitute a significant part of the caves in the world, have been the habitat of old people for almost 1-1.5 million years. The caves have been very important shelters for life, which became difficult due to the cold climatic conditions during the glacial periods, which were effective during the last 2 million years (Pleistocene). Under the challenging conditions of the Paleolithic period, human societies have tried to survive on the one hand and, on the other hand, achieved their symbolic thinking skills with their developing brain capacities 100,000 years ago. In the following period, the human communities that continued to develop have left very important ruins, which dates back to 40-10 thousand years ago and are regarded as works of art. Structural features of the caves and the rocks forming them are of great importance in the emergence of these works, which are interesting in their techniques as well as their thought style. Karst caves are very suitable for processing in terms of scraping, embossing and various painting techniques depending on the mineral structure of limestone. Besides, since these caves are difficult to access and are prevented from external dangers and risks, they are of great importance for the emergence of this art and reaching to the present day.
Keywords: Cave, Karstic rock, Cave art
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Szczygieł, Jacek, and Maciej J. Mendecki. "Preliminary results of fractal analysis of the poligonal survey from cave: case study of Małołączniak area (Tatra Mts.)." Contemporary Trends in Geoscience 2, no. 1 (September 1, 2013): 95–100. http://dx.doi.org/10.2478/ctg-2014-0014.
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Abstract Traverses (polygons) from two caves have been tested: Wielka Śnieżna Cave System (2858 vectors) and Śnieżna Studnia cave (742). The box counting technique was applied to evaluate the fractal analysis of spatial orientation of traverses. The polygonal survey of Wielka Śnieżna Cave, Śnieżna Studnia and both caves merged together have a fractal geometry. It may be concluded that these caves are close to the full recognition of passages forming by a hydrological system and they could have close relation with geological structures. The usual explanation of fractal dimension D higher than 1 indicates that caves with such dimension fill more space than those with ideal dimension of 1.00 (for example a straight line), and the geological constraints limit the dimension to be lower than 2 (Verbovsek 2007). It may suggest that systems can be developped into more complicated passages in future. The fact that both caves merged together also have showed fractal geometry indicates that they are belonging to the same hydrological system. It was noticed that D-value of merged caves is slightly larger than individual cave. It can be explained by “occupying” more space in rock mass.
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Perry, Roger W. "A review of factors affecting cave climates for hibernating bats in temperate North America." Environmental Reviews 21, no. 1 (March 2013): 28–39. http://dx.doi.org/10.1139/er-2012-0042.
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The fungal pathogen Geomyces destructans, which causes white-nose syndrome in bats, thrives in the cold and moist conditions found in caves where bats hibernate. To aid managers and researchers address this disease, an updated and accessible review of cave hibernacula and cave microclimates is presented. To maximize energy savings and reduce evaporative water loss during winter, most temperate vespertilionid bats in North America select caves with temperatures between 2 and 10 °C, with 60%–100% relative humidity. Generally, the temperature in caves is similar to the mean annual surface temperature (MAST) of a region, which varies by latitude, altitude, and topography. However, MAST for most areas where caves are found in eastern North America is well above 10 °C. Thus, various factors cause cold-air infiltration that reduces temperatures of these caves during winter. These factors include depth of cave, topographic setting, airflow patterns, cave configuration, and water infiltration. Factors affecting humidity, condensation, and evaporation are also addressed. In areas where MAST is above or below the thermal requirements of Geomyces destructans, many caves used by bats as hibernacula may still provide favorable sites for optimal growth of this fungus.
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Ficetola, Gentile Francesco, Roberta Pennati, and Raoul Manenti. "Do cave salamanders occur randomly in cavities? An analysis with Hydromantes strinatii." Amphibia-Reptilia 33, no. 2 (2012): 251–59. http://dx.doi.org/10.1163/156853812x638536.
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Underground environments are increasingly recognised as important habitats for the distribution of certain amphibians. However, very few analyses tested whether amphibians occur randomly in underground environments, or they select cavities with specific environmental features. We assessed the distribution of the cave salamander Hydromantes (Speleomantes) strinatii in an area of NW Italy during summer, and analysed relationships between salamander distribution and multiple cave features, considering parameters describing both the biotic and the abiotic environment. Using visual encounter surveys, species’ detection probability was high, indicating that this technique provides reliable information on distribution. Salamanders were associated to caves with cold and humid microclimate, presence of wet walls, and hosting large numbers of Meta spiders. The association with less luminous caves was close to significance. Distribution data were not affected by spatial autocorrelation, suggesting that cave features are more important than the proximity to other occupied caves in determining the pattern of occupancy. Caves are heterogeneous environments: cave salamanders are strongly related to the features of underground environments. Food availability and abiotic features are major determinants of suitability for cave salamanders. Inter-correlation among biotic and abiotic cave features makes it complex identifying the role of factors determining species distribution, but quantitative analyses and PCA help to unravel the cave habitat requirements for amphibians.
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Pate, Dale L., and Ronal C. Kerbo. "Understanding and preserving caves and karst landscapes." Earth Sciences History 36, no. 2 (January 1, 2017): 318–36. http://dx.doi.org/10.17704/1944-6178-36.2.318.
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ABSTRACT Beginning in 1903 with the creation of Wind Cave National Park, ten National Park Service units have been created because of the caves they contained. Since the establishment of the National Park Service in 1916, over 5,360 caves are known to exist within at least 99 park units. These caves are found in different types of rocks and were formed by several different mechanisms. The most prolific landscapes that have formed caves are those in soluble rocks such as limestone. Known as karst landscapes, at least 114 park units contain some amount of karst. In the early days, cave parks were developed for their commercial and recreational values. Little was known of the processes that created caves or the many resources that encompassed these entire landscapes. With the help of cave and karst enthusiasts and researchers, and the advent of cave and karst resource managers, the National Park Service has made great strides in understanding these resources. This has led to increased educational opportunities and better management decisions that will enhance long-term preservation of these resources.
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Diedrich, Cajus G. "Steppe lion remains imported by Ice Age spotted hyenas into the Late Pleistocene Perick Caves hyena den in northern Germany." Quaternary Research 71, no. 3 (May 2009): 361–74. http://dx.doi.org/10.1016/j.yqres.2008.12.006.
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AbstractUpper Pleistocene remains of the Ice Age steppe lion Panthera leo spelaea (Goldfuss, 1810) have been found in the Perick Caves, Sauerland Karst, NW Germany. Bones from many hyenas and their imported prey dating from the Lower to Middle Weichselian have also been recovered from the Perick Cave hyena den. These are commonly cracked or exhibit deep chew marks. The absence of lion cub bones, in contrast to hyena and cave bear cub remains in the Perick Caves, and other caves of northern Germany, excludes the possibility that P. leo spelaea used the cave for raising cubs. Only in the Wilhelms Cave was a single skeleton of a cub found in a hyena den. Evidence of the chewing, nibbling and cracking of lion bones and crania must have resulted from the importation and destruction of lion carcasses (4% of the prey fauna). Similar evidence was preserved at other hyena den caves and open air sites in Germany. The bone material from the Perick and other Central European caves points to antagonistic hyena and lion conflicts, similar to clashes of their modern African relatives.
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Ereskovsky, Alexander, Oleg A. Kovtun, Konstantin K. Pronin, Apostol Apostolov, Dirk Erpenbeck, and Viatcheslav Ivanenko. "Sponge community of the western Black Sea shallow water caves: diversity and spatial distribution." PeerJ 6 (May 8, 2018): e4596. http://dx.doi.org/10.7717/peerj.4596.
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Marine caves possess unique biocoenotic and ecological characteristics. Sessile benthic species such as sponges associated with cave habitats typically show a marked zonation from the cave entrance towards the end of the cave. We describe three semi-submerged karstic caves of 50 to 83 m length and 936 to 2,291 m3volume from the poorly explored cavernicolous fauna of North-East Bulgaria. We surveyed sponge diversity and spatial variability. Eight demosponge species were identified based on morphological and molecular data, of which six are known from the adjacent open sea waters of the Black Sea. Two species,Protosuberites denhartogivan Soest & de Kluijver, 2003 andHalichondria bowerbankiBurton, 1930, are reported from the Black Sea for the first time. The spatial sponge distribution inside the caves is in general similar, but shows some differences in species composition and distribution depending on cave relief and hydrodynamics. The species composition of sponges of Bulgarian caves is found to be different from Crimean caves. An updated checklist of the Black Sea sponges is provided.
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Moldovan, O. T., A. Mihevc, L. Mikó, S. Constantin, I. Meleg, A. Petculescu, and P. Bosák. "Invertebrate fossils from cave sediments: a new proxy for pre-Quaternary paleoenvironments." Biogeosciences Discussions 8, no. 2 (March 30, 2011): 3403–34. http://dx.doi.org/10.5194/bgd-8-3403-2011.
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Abstract. Five samples of clastic sediments from interior cave facies taken in three Slovenian relic caves (Trhlovca, Račiška pečina, and a cave in Črnotiče Quarry, Classical Karst, SW Slovenia) provided invertebrate fossil remains. Most of them belong to Oribatida but sparse individuals of Cladocera and insects were also identified. They represent the first pre-Quaternary invertebrate fossils found in sediments of continental temperate climate. The Pliocene/Pleistocene age of the sediments was determined by paleomagnetic dating chronologically calibrated by micromammal biostratigraphy. Invertebrate fossils could be validated as new proxy for the study of cave sediments due to their suitability for ecological and paleogeographic correlations in caves and outside the caves. They also bring additional information about cave formation and karst hydraulic regime in the area. Even if the number of remains was very low, it represents evidence that climatic conditions in caves allow a better preservation of fossil remains of some groups as compared to most of the surface habitats. This may open a new direction in the study of cave sediments.
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Moldovan, O. T., A. Mihevc, L. Miko, S. Constantin, I. N. Meleg, A. Petculescu, and P. Bosák. "Invertebrate fossils from cave sediments: a new proxy for pre-Quaternary paleoenvironments." Biogeosciences 8, no. 7 (July 11, 2011): 1825–37. http://dx.doi.org/10.5194/bg-8-1825-2011.
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Abstract. Five samples of clastic sediments from interior cave facies taken in three Slovenian relic caves (Trhlovca, Račiška pečina, and a cave in Črnotiče Quarry, Classical Karst, SW Slovenia) provided invertebrate fossil remains. Most of them belong to Oribatida but sparse individuals of Cladocera and insects were also identified. They represent the first pre-Quaternary invertebrate fossils found in sediments of continental temperate climate. The Pliocene/Pleistocene age of the sediments was determined by paleomagnetic dating chronologically calibrated by micromammal biostratigraphy. Invertebrate fossils could be validated as new proxy for the study of cave sediments due to their suitability for ecological and paleogeographic correlations in caves and outside the caves. They also bring additional information about cave formation and karst hydraulic regime in the area. Although the number of remains was very low, it is evidence that climatic conditions in caves allow a better preservation of fossil remains of some groups as compared to most of the surface habitats. This may open a new direction in the study of cave sediments.
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Bejec, Gilbert A., Lilibeth A. Bucol, Tomas D. Reyes, Reizl P. Jose, Agustin B. Angcog, Albert C. Pagente, Josie M. Rodriguez, Anna Lee N. Bejec, and Neri Fretz P. Paglinawan. "Abundance and Species Composition of Cave Bats (Mammalia: Chiroptera) in Selected Key Biodiversity Areas (KBAs) of Central Visayas, Philippines." JURNAL ILMIAH SAINS 21, no. 1 (April 27, 2021): 73. http://dx.doi.org/10.35799/jis.21.1.2021.31238.
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This study assessed the abundance and species richness of bats (Order Chiroptera) inhabiting caves in three KBAs (Key Biodiversity Areas) of Central Visayas: Mt. Bandilaan in Siquijor (13 caves), Mabinay, Negros Oriental (11 caves), and Rajah Sikatuna Protected Landscape(RSPL) in Bohol (31 caves). The study was conducted between February 14 to September 20, 2019. Of the 55 caves surveyed, 35 caves were inhabited by bats. Field survey methods included mist-netting at the cave entrances and direct observations of roosting sites in each cave. This study captured 754 individuals of bats belonging to 16 species, majority of which are insectivorous species (13 species) and only three species are fruitbats (Pteropodidae). Mabinay caves had the highest number of species (11) and captured bats (271 individuals) while RSPL had 9 species (221 individuals) while Mt. Bandilaan only had five species but relatively high captured bats (262 individuals). Five species are Philippine endemics (Hipposideros obscurus, Hipposideros pygmaeus, Ptenochirus jagori, Rhinolophus inops, and R. rufus) and three Near-threatened species (H. lekaguli, M. schreibersii, and R. rufus). The rare bat species (Dobsonia chapmani) may be locally extirpated in Mabinay, where it last documented at Mambajo cave in the 1960s. The survey also noted the absence of fruit bats (observed in 2011 study) in all of the caves in Mt. Bandilaan, probably due to on-going anthropogenic activities (treasure hunting, bat hunting, guano extraction, land conversion, locals illegal entry, graffiti, etc) in caves surveyed. Large colonies of fruitbats and insect bats in RSPL may have been affected by anthropogenic activities inside the caves. Most of the caves surveyed have been promoted for ecotourism activities.Keywords: cave; chiropteran; extraction; karst; limestone
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Xu, Wei Wu, and Qiu Xiang Gu. "Lower-Middle Ordovician Cave-Reservoir Characters and Dominant Factors in Southern Tahe Oil Field." Advanced Materials Research 1010-1012 (August 2014): 1408–12. http://dx.doi.org/10.4028/www.scientific.net/amr.1010-1012.1408.
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It is discussed characteristic and dominant factors of lower-middle Ordovician cave-reservoir in southern Tahe oilfield by analyzing data such as core, well drilling, logging, and seismic systematically, and by applying reservoir identifying, wells comparing, section of seismic analyzing, and ancient physiognomy recovering technology in this article. Three cave layers effected by the early hercynian karstification have been discovered in the study area. In single well section, the cave layer with strong heterogeneity corresponds with the Karst cycle with six combinations. The cave layers dominated by the early hercynian unconformity concentrate under0-200metre of the unconformity surface. The nearer to the unconformity surface, the more caves are filled. With effecting of fracture, the caves layers, especially larger cave, are often discovered in fractures concentrated zone. With effecting of ancient physiognomy, the caves layers are often in gentle carbonate slope. The unconformity, regional fractures and ancient physiognomy are the dominant factors of lower-middle Ordovician cave-reservoir in southern Tahe oil field.
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Tičar, J., N. Tomić, M. Breg Valjavec, M. Zorn, S. B. Marković, and M. B. Gavrilov. "Speleotourism in Slovenia: balancing between mass tourism and geoheritage protection." Open Geosciences 10, no. 1 (August 11, 2018): 344–57. http://dx.doi.org/10.1515/geo-2018-0027.
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Abstract Slovenia is considered as the cradle of karst geotourism as cave tourism started there as early as the Middle Ages. To date more than 12,000 caves were discovered from which 22 have the status of tourist caves. From these, 10 were assessed using the M-GAM model (Modified Geosite Assessment Model) to gain information for better future management strategies. The results show that visitors of Slovenian tourist caves mostly appreciate their natural values, as they prefer caves without major tourism infrastructure and they pay attention to their protection status. The model also confirmed that the two most important tourist caves (Postojna Cave and Škocjan Caves) have the leading geotourism role and that the management of tourist caves via a regional park as is the case of Škocjan Caves is an example of good practice.
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Paksuz, Serbülent, and Beytullah Özkan. "The protection of the bat community in the Dupnisa Cave System, Turkey, following opening for tourism." Oryx 46, no. 1 (January 2012): 130–36. http://dx.doi.org/10.1017/s0030605310001493.
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AbstractThe aim of this study was to protect the bat community and roosting sites in the Dupnisa Cave System in the Yıldız (Istranca) Mountains in Thrace, the European part of Turkey, following the opening of the caves to tourism. We investigated the seasonal population dynamics and use of the cave system by bats, carrying out 15 surveys before (2002–2003) and 38 surveys after (2004–2008) the cave system was opened to tourism. We recorded 15 species of bats; the highest numbers recorded in a single survey were 54,600 hibernating and 11,000 breeding/nursing. Different parts of the cave system are used by bats to various degrees according to season. To protect the bats and the cave system the visitor schedule took into consideration the differences in seasonal use of the caves by bats. There was a significant increase in the total number of bats recorded in the cave system after opening for tourism, possibly because the gating of two entrances helped to control visitation. The results of our surveys of this cave system show that gating of entrances and visits by tourists are not necessarily incompatible with the use of caves by bats for both hibernating and nursing. Understanding how the three caves are used seasonally by the bat community, and for what purposes (hibernation vs nursing), was critical for the establishment of an appropriate management plan for tourism.
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Dáttilo, Wesley. "Influence of Cave Size and Presence of Bat Guano on Ant Visitation." Sociobiology 59, no. 2 (September 26, 2014): 549. http://dx.doi.org/10.13102/sociobiology.v59i2.617.
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This is the first study which evaluated the influence of cave size and presence of bat guano in ant visitation in Brazilian caves. We provide a list of the ants associated with 27 caves in northeastern Brazil, an area situated in the transition between Cerrado (Brazilian savanna) and Amazon Domain. The study was conducted between January and August 2010. We recorded 24 ant species inserted into 12 genera, 10 tribes, and six subfamilies. The size of the cave and the presence of guano did not influence the richness of ants, and most of the caves had single species. Camponotus atriceps was the species with the larger distribution, being collected in five caves. In addition, we discuss geographic distribution of records and possible ecological roles of ants in cave environments.
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Qinglin, Guo, Hiromi Takabayashi, Toshio Nakamura, Chen Gangquan, Ken Okada, Su Bomin, Fan Yuquan, and Hiroshi Nishimoto. "Radiocarbon Chronology for Early Caves of the Mogao Grottoes at Dunhuang, China." Radiocarbon 52, no. 2 (2010): 500–510. http://dx.doi.org/10.1017/s0033822200045537.
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The Mogao Grottoes site at Dunhuang is one of the largest stone cave temples in China. The site features 735 caves with Buddhist mural paintings. To investigate the chronology of early caves of the Mogao Grottoes, radiocarbon dates were measured by accelerator mass spectrometry (AMS) on plant remains collected from 4 caves: 268, 272, 275, and 285. Caves 268, 272, and 275 are regarded (by archaeological analysis) to be the earliest existing caves in the Mogao Grottoes. The fourth cave, 285, features inscriptions on the north wall mentioning the oldest dates of the Chinese Mogao era. Plant materials, taken from the plaster layer of mural paintings and core materials from statues, were collected as samples (n = 11) for AMS 14C dating at Nagoya University. Two samples from cave 275 gave calibrated 14C ages of cal AD 380–430 (1 σ). The other samples resulted in a time interval of cal AD 400–550. The calibrated 14C ages obtained for the samples taken from painted murals and the statues in cave 285 are consistent with the date given by the inscription remaining on the cave's north wall.
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Iliffe, Thomas M., and Fernando Calderón-Gutiérrez. "Bermuda’s Walsingham Caves: A Global Hotspot for Anchialine Stygobionts." Diversity 13, no. 8 (July 30, 2021): 352. http://dx.doi.org/10.3390/d13080352.
Full textAbstract:
Bermuda is an Eocene age volcanic island in the western North Atlantic, entirely capped by Pleistocene eolian limestone. The oldest and most highly karstified limestone is a 2 km2 outcrop of the Walsingham Formation containing most of the island’s 150+ caves. Extensive networks of submerged cave passageways, flooded by saltwater, extend under the island. In the early 1980s, cave divers initially discovered an exceptionally rich and diverse anchialine community inhabiting deeper sections of the caves. The fauna inhabiting caves in the Walsingham Tract consists of 78 described species of cave-dwelling invertebrates, including 63 stygobionts and 15 stygophiles. Thus, it represents one of the world’s top hotspots of subterranean biodiversity. Of the anchialine fauna, 65 of the 78 species are endemic to Bermuda, while 66 of the 78 are crustaceans. The majority of the cave species are limited in their distribution to just one or only a few adjacent caves. Due to Bermuda’s high population density, water pollution, construction, limestone quarries, and trash dumping produce severe pressures on cave fauna and groundwater health. Consequently, the IUCN Red List includes 25 of Bermuda’s stygobiont species as critically endangered.
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Gullberg, Steven R., and J. McKim Malville. "Caves, Liminality, and the Sun in the Inca World." Culture and Cosmos 21, no. 1 and 2 (2017): 193–214. http://dx.doi.org/10.46472/cc.01221.0221.
Full textAbstract:
Caves were liminal features of the Inca sacred landscape, connecting this world with the underworld. They were places for making contact with ancestors and the powers of creation. In this paper we examine caves in southeastern Peru for solar orientations and cosmological context, with recourse to the concept of liminality that appears central to cave use. The cave within Kenko Grande has ceremonial steps adjacent to an altar upon which sunlight climbs at midday in June. A rear entrance and altar are illuminated at the time of the solar equinox sunrises. Lacco has three caves which have one solsticial orientation and two light-tubes. A primary opening in the cave at Lanlakuyok faces sunrise at the time of the equinoxes. Tambomachay contains a major fountain and a cave with a platform oriented to December solstice sunrise. Rumiwasi Bajo contains a number of niches and a nine-meter-long passageway oriented close to the June solstice sunset, while the other door opens to December solstice sunrise. Choquequilla is a complex cave opening to December solstice sunrise. The Royal Mausoleum is one of the major shrines of Machu Picchu and opens to June solstice sunrise. Intimachay is a cave with a constructed opening for the December solstice sunrise. The Temple of the Condor contains a cave approximately open to the anti-zenith sunrise. The Gran Caverna includes both an upper and a lower cave oriented for June solstice sunset. There are two caves at the River Intihuatana that, while part of an astronomically oriented complex, don’t have solstitial nor equinoctial orientations, nor do they have interior carvings. We end the paper by considering the role of caves and liminality in Inca cosmology.