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Site-specific Dose Conversion Factors (DCFs) for radon progeny were estimated based on the aerosol measurement results in an outdoor environment and a tourist cave. The Activity Median Diameter (AMD) and unattached fraction were measured and used to calculate the effective dose per unit intake of radon progeny. The AMDs in the outdoor environment was in the range of 0.24–0.71 μm with the unattached fraction of 0.17. In the tourist cave, two peaks were found in the aerosol size distribution at nucleation and accumulation modes and the unattached fraction was measured to be 0.69 with a range of 0.36–0.85. The DCFs at the outdoor environment did not differ from those from the publication of the International Commission on Radiological Protection; however, the DCF in the tourist cave was significantly higher due to the discrepancy in the unattached fraction and the aerosol size distribution. It was found that these two factors would significantly affect the DCF so that we should be aware of it. [ABSTRACT FROM AUTHOR]

San Nicola Island, pertaining to the Tremiti Archipelago (Southern Adriatic Sea, Italy), is widely affected by cliff retreat and gravitational phenomena which severely threaten its monumental historical and natural value. In this study, geomorphological features of the area were derived following a stepwise approach, combining multitemporal stereoscopic aerial photo interpretations with morphometric analyses and detailed field surveys. A rockfall susceptibility map was created following a heuristic approach based on morphometric and geothematic parameters, accounting for slope, slope aspect, outcropping lithologies, structural discontinuities density, distance from landslide scarps, and presence of anthropic caves. Cliff sectors set on dolomitic limestones feature the highest susceptibility values, especially along the southeastern sector; medium values, instead, are found along the island flanks and along scarps located within the inner sectors; and the lowest values are detected on summit tabular surfaces. The achieved results were compared with historical maps and seismic data derived from local and national archives and catalogues, respectively. These analyses allowed us to define the role played by litho-structural and tectonic features on landslide occurrence and distribution, and their interplay in driving landscape evolution over centuries. Finally, this work represents a valuable scientific tool to support geomorphological studies for landslide hazard assessment and proper territorial planning in any other small insular areas, showing similar geological–geomorphological features and landscape values. [ABSTRACT FROM AUTHOR]

In comparison to temperate and arid regions, environmental responses to the Last Glacial Maximum and the Terminal Pleistocene and Holocene boundary remain poorly known for many parts of the tropics, making it challenging to unravel human–landscape interactions across this timeframe. This is particularly the case in insular Near Oceania, where sea‐level fluctuations and potential changes in forest cover may have had major impacts on hunter–gatherer populations. Here, we apply stable carbon and oxygen isotope analyses to small‐mammal teeth from four Pleistocene–Holocene (spanning from 29 000 years ago to the late Holocene) sequences in the Bismarck Archipelago to reconstruct changes in environments directly exploited by human populations in this part of the world. Our results show a subtle response of tropical habitats in Near Oceania to relatively arid conditions during the late‐glacial period, something that has also been observed at sites in South and Southeast Asia, followed by a Terminal Pleistocene–Holocene expansion of tropical forest cover. Nevertheless, site‐based variability in environmental responses across this period highlight the need for more multidisciplinary studies of human occupation sequences in a region that is becoming increasingly central to exploring human adaptations, environmental modifications and social network development over the past 20 000 years. [ABSTRACT FROM AUTHOR]

The low latitude Indian Ocean is warming faster than other tropical basins, and its interannual climate variability is projected to become more extreme under future emissions scenarios with substantial impacts on developing Indian Ocean rim countries. Therefore, it has become increasingly important to understand the drivers of regional precipitation in a changing climate. Here we present a new speleothem record from Anjohibe, a cave in northwest (NW) Madagascar well situated to record past changes in the Intertropical Convergence Zone (ITCZ). U‐Th ages date speleothem growth from 27 to 14 ka. δ18O, δ13C, and trace metal proxies reconstruct drier conditions during Heinrich Stadials 1 and 2, and wetter conditions during the Last Glacial Maximum and Bølling–Allerød. This is surprising considering hypotheses arguing for southward (northward) ITCZ shifts during North Atlantic cooling (warming) events, which would be expected to result in wetter (drier) conditions at Anjohibe in the Southern Hemisphere tropics. The reconstructed Indian Ocean zonal (west‐east) sea surface temperature (SST) gradient is in close agreement with hydroclimate proxies in NW Madagascar, with periods of increased precipitation correlating with relatively warmer conditions in the western Indian Ocean and cooler conditions in the eastern Indian Ocean. Such gradients could drive long‐term shifts in the strength of the Walker circulation with widespread effects on hydroclimate across East Africa. These results suggest that during abrupt millennial‐scale climate changes, it is not meridional ITCZ shifts, but the tropical Indian Ocean SST gradient and Walker circulation driving East African hydroclimate variability. Plain Language Summary: Long term monsoon dynamics in the southern Indian Ocean and Global South are not well constrained due to a lack of observational data. Paleoclimate records generated from archives like speleothems can help us fill gaps in our understanding. Here we use a speleothem record from Madagascar to test whether north‐south shifts in the tropical rain belt or west‐east changes in Indian Ocean temperatures are more important for precipitation in tropical East Africa. We find that ocean temperature gradients are the most important control on precipitation at our study site during previous instances of abrupt climate change linked to variability in the strength of North Atlantic ocean circulation. This work has important implications for how we think about the future of the tropical Indian Ocean sector in a changing climate. Key Points: Speleothem stable isotope and trace metal data agree on a dry Heinrich Stadial 1 and a wet Bølling–Allerød in northwest MadagascarHeinrich Stadial 1 and the Bølling‐Allerød show conditions contrary to responses expected from north‐south Intertropical Convergence Zone shiftsMillennial‐scale tropical East African hydroclimate variability is likely driven by zonal Indian Ocean sea surface temperature gradients [ABSTRACT FROM AUTHOR]

Understanding how El Niño‐Southern Oscillation (ENSO) responds to natural variability is of key importance for future climate projections under a warming climate. However, there is no clear consensus on what drives ENSO's variability on centennial timescales. Here, we find that the epikarst in southeastern Alaska is effective at filtering ENSO and solar irradiance signals from the Aleutian Low regional climate, which are subsequently recorded in speleothem proxy data. By applying a correlation test, we find that ENSO was significantly influenced by solar irradiance over the past ∼3,500 years. This relationship dissolved after ∼1970 CE, with ENSO now being dominated by anthropogenic forcing. This implies a new ENSO mean state that will need to be incorporated into future climate projections. Plain Language Summary: Although El Niño‐Southern Oscillation (ENSO) is one of the most important climate phenomena globally, it is currently unknown how ENSO responds to natural variability on timescales over 100 years. Natural variability refers to periodic changes in climate due to either solar forcing, the circulation of the atmosphere and ocean, volcanic eruptions, and other factors, irrespective of human intervention. Here, we help solve this problem by studying deposits in caves (speleothems) from Alaska. The speleothems are excellent at capturing atmospheric conditions over the past 3,500 years, and show that solar forcing was significantly controlling ENSO variability. However, the speleothems also show that humans have altered this natural variability, with ENSO entering a new mean state after ∼1970 CE. Key Points: Speleothems from southeastern Alaska capture El Niño‐Southern Oscillation (ENSO) variability through a teleconnection with the Aleutian LowENSO variability was strongly influenced by solar forcing before ∼1970 CEENSO significantly changed properties at ∼1970 CE, likely due to anthropogenic forcing [ABSTRACT FROM AUTHOR]

Speleothems, particularly stalagmites are extensively used to reconstruct paleoclimatic and paleomonsoon changes by using stable oxygen and carbon isotopes along the growth profile of a stalagmite sample. Trace and rare earth elements (REEs) variations in stalagmites are widely recognized as indicators of past precipitation and local hydrology. The amalgamation of isotopic and trace element proxies in speleothems has been regarded as an important tool to infer past climate and hydro-chemical fluctuations. Current advancements in geochemical techniques have enabled us to generate high-resolution paleo-records of almost all trace and REEs from stalagmites. However, their assessment is dependent on numerous factors that control the formation of a stalagmite. Here we present a geochemical record from a well dated stalagmite (VSPM1) from a cave located in the southern India. The stalagmite grew between 15,610 and 13,160 yr BP as revealed by its StalAge modelled ages from eight U–Th dates. This study demonstrates significant variations in trace and REEs during the last deglacial time interval of 2100 years and suggests variations in drip water chemistry. The relative amount of trace elements in colloidal solutions originating from the soil organics and weathered particles of host dolomitic rock may have altered with climatic changes. It appears that trace and REEs of VSPM1 stalagmite have responded to fluctuations in Indian Summer Monsoon (ISM) intensity during the time interval of this study. [ABSTRACT FROM AUTHOR]

Different from the goaf formed by normal mining, the goaf formed by the continuous caving of the lower illegal goafs is extremely irregular and unstable, which leads to the difference in the goaf caving characteristics. Taking the complex irregular goaf of the Shirengou Iron Mine in China as the research object, the 3D laser scanning technology is used to detect the goaf shape and analyze the cause of the formation. Then, the caving characteristics of the goaf are analyzed by the methods of the numerical simulation, the monitoring of the crash of the caving rock, and the monitoring of the deformation of the arch foot. The simulation results show that the transverse expansion of the irregular goaf boundary is mainly along the perpendicular to the direction of the ore body strike when the goaf caves upward in the initial stage. Additionally, the monitoring results show that the caving characteristics can be divided into two stages: the paroxysmal caving stage and the periodicity caving stage. The paroxysmal caving characteristics are intense and irregular, while the periodicity caving characteristics have obvious periodicity, which is mainly reflected in the periodic alternation between the mass caving and the temporary stability. The interval period of the goaf mass caving is about 15–30 days and is changed by the progress of filling treatment. The conclusions in this work reveal the particularity of the caving characteristics in the complex irregular goaf and contribute to the improvement of the caving characteristics and the prediction of mass caving. [ABSTRACT FROM AUTHOR]

Bats are excellent bioindicators and are increasingly used to assess ecosystem health and monitor changes in the environment. Due to increased awareness of the potential transmission of pathogens from bats to humans and recognizing the limitations of traditional bat sampling methods, the use of of non-invasive sampling techniques such as bat recorders were recommended for field-based monitoring studies. In the Philippines, however, bat bioacoustics is still a growing field, and the scarcity of acoustic data hinders the use of echolocation calls to conduct accurate inventories and population monitoring of echolocating bats. Here, we recorded and characterized echolocation calls of insectivorous bats from caves and karst areas located in southern Luzon Island, Philippines. In addition, we compared our results with other studies performed within and outside the country to identify possible regional and local variation in acoustic characters for some species. A total of 441 echolocation calls were recorded from six bat families: Hipposideridae (five species), Rhinolophidae (five species), Vespertilionidae (three species), Miniopteridae (two species), Megadermatidae (one species), and Emballonuridae (one species). Discriminant function analyses (DFA) with leave-one-out cross validation correctly classified bats emitting calls dominated with a constant frequency (CF) component (rhinolophids and hipposiderids) with >97% success and those producing frequency modulated (FM) calls (Miniopteridae and Vespertilionidae) with 88.9% success. We report echolocation calls for Philippine population of two species (Megaderma spasma and Hipposideros lekaguli) for the first time. Moreover, we present geographical variations in call frequencies for some species by comparing previously reported acoustic data elsewhere across the species' range. This underscores the importance of establishing a readily accessible and comprehensive local reference library of echolocation calls which would serve as a valuable resource for examining taxonomic identities of echolocating bats, particularly those whose calls exhibit biogeographic variations. [ABSTRACT FROM AUTHOR]

The Astyanax mexicanus complex includes two different morphs, a surface‐ and a cave‐adapted ecotype, found at three mountain ranges in Northeastern Mexico: Sierra de El Abra, Sierra de Guatemala and Sierra de la Colmena (Micos). Since their discovery, multiple studies have attempted to characterize the timing and the number of events that gave rise to the evolution of these cave‐adapted ecotypes. Here, using RADseq and genome‐wide sequencing, we assessed the phylogenetic relationships, genetic structure and gene flow events between the cave and surface Astyanax mexicanus populations, to estimate the tempo and mode of evolution of the cave‐adapted ecotypes. We also evaluated the body shape evolution across different cave lineages using geometric morphometrics to examine the role of phylogenetic signal versus environmental pressures. We found strong evidence of parallel evolution of cave‐adapted ecotypes derived from two separate lineages of surface fish and hypothesize that there may be up to four independent invasions of caves from surface fish. Moreover, a strong congruence between the genetic structure and geographic distribution was observed across the cave populations, with the Sierra de Guatemala the region exhibiting most genetic drift among the cave populations analysed. Interestingly, we found no evidence of phylogenetic signal in body shape evolution, but we found support for parallel evolution in body shape across independent cave lineages, with cavefish from the Sierra de El Abra reflecting the most divergent morphology relative to surface and other cavefish populations. [ABSTRACT FROM AUTHOR]

Atxurra cave has a decorated assemblage composed of more than a hundred engraved animal depictions. All of them are located in deep parts of the cave and most of them are hidden in raised areas, away from the main path. The main sector is the "Ledge of the Horses", located at 330 m from the entrance of the cave. It is a space of 12 m long and 1.5 m wide, elevated 4 m above the cave floor. This area includes almost fifty engraved and painted animals accompanied by a dozen flint tools, three fireplaces, and around one hundred charcoal fragments from torches. This extraordinary archaeological record allows us to value the complexity of the artistic production inside the caves during the Upper Palaeolithic. Our study has confirmed that there is planning prior to artistic production, both in terms of the iconographic aspects (themes, techniques, formats), its location (visibility, capacity), and the lighting systems. Furthermore, the data indicates the panel was decorated to be seen by third parties from different positions and was expressly illuminated for this purpose. This evidence supports the role of rock art as a visual communication system in Upper Palaeolithic societies. [ABSTRACT FROM AUTHOR]

The Borra caves, the second largest subterranean karst cave ecosystem in the Indian sub-continent, are located at the Ananthagiri hills of Araku Valley in the Alluri district of Andhra Pradesh, India. The present investigation applied a shotgun metagenomic approach to gain insights into the microbial community structure, metabolic potential, and biosynthetic gene cluster (BGC) diversity of the microbes colonizing the surface of the speleothems from the aphotic zone of Borra caves. The taxonomic analysis of the metagenome data illustrated that the speleothem-colonizing core microbial community was dominated mainly by Alpha-, Beta-, and Gamma-Proteobacteria, Actinobacteria, Firmicutes, and Bacteroidetes. The key energy metabolic pathways analysis provides strong evidence of chemolithoautotrophic and chemoheterotrophic modes of nutrition in the speleothem-colonizing microbial community. Metagenome data suggests that sulfur reducers and sulfur-disproportionating microbes might play a vital role in energy generation in this ecosystem. Our metagenome data also suggest that the dissimilatory nitrifiers and nitrifying denitrifiers might play an essential role in conserving nitrogen pools in the ecosystem. Furthermore, metagenome-wide BGCs mining retrieved 451 putative BGCs; NRPS was the most abundant (24%). Phylogenetic analysis of the C domain of NRPS showed that sequences were distributed across all six function categories of the known C domain, including several novel subclades. For example, a novel subclade had been recovered within the LCL domain clade as a sister subclade of immunosuppressant cyclosporin encoding C domain sequences. Our result suggested that subterranean cave microbiomes might be a potential reservoir of novel microbial metabolites. [ABSTRACT FROM AUTHOR]

Rudimentary structures are variable, which is most impressively demonstrated by the eyes and dark body pigmentation of species evolving in caves. As these can often still be crossed with their ancestral surface sister forms, variability is usually attributed to hybridization. For two invertebrate and two vertebrate cave species, I show here that in spite of genetic separation between surface and cave forms, variability of the rudimentary structures is nonetheless present. This probably results from the loss of stabilizing selection, because neutral deleterious mutations are no longer eliminated. In contrast, compensatory traits in caves do not differ from their surface forms with respect to variability, because both are subject to selection. In the phylogenetically young Astyanax cave populations, traits compensatory to cave life have achieved different stages of adaptation compared to the phylogenetically old populations. They may show the same degree of differentiation, be intermediate or do not differ from the surface ancestor. This is attributed to different intensities of selection. [ABSTRACT FROM AUTHOR]

As a unique ecosystem, Karst caves harbor an impressive diversity of specific fungi. However, the factors and mechanisms that shape fungal biodiversity in caves remain elusive. In this study, we explored the assembly patterns of fungal communities based on our previous research in eight representative Karst caves in Southwest China. Our results indicated that dispersal limitation plays a crucial role in shaping the overall fungal community as well as specific communities in rock, sediment, and water samples. However, "Undominated" processes contributed more than dispersal limitation in air samples. Interestingly, the dominant assembly processes varied between caves. Consistently, environmental selection had a minor impact on the assembly of fungal communities. Among the examined spatial and environmental variables, latitude, longitude, altitude, and temperature were found to significantly influence fungal communities irrespective of substrate type. These findings provide valuable insights into the ecological factors governing fungal community assembly in Karst caves. [ABSTRACT FROM AUTHOR]

Bulk ore sorting is a preconcentration method applied to bulk streams or batches of material. The effectiveness of bulk ore sorting relies on the degree of the naturally occurring in situ grade heterogeneity of an ore deposit. The blending of ore during mining and material handling degrades the in situ grade heterogeneity initially present in an orebody and reduces the potential to apply bulk ore sorting. Block and panel cave mines experience mixing from the establishment of caves to the delivery of the caved ore to concentrators. This study focused on tracking the grade heterogeneity and quantifying the impact of mixing on the sorting potential of the Cadia East panel cave mine via the reconciliation of the grade measurements performed at different locations. The results showed that the copper and gold grades were almost fully homogenized via various mixing events identified for the mine. The tracked grade heterogeneity values revealed that the mixing during material handling, which included ore blending according to mine planning, reduced the grade variability more drastically than the mixing within the caves. As the ore travelled from its original in situ location, the grade distributions gradually transformed, and the grades eventually normalized around the mean values. Only insignificant amounts of low-grade material that could have potentially been discarded were reported to the on-belt sensor located at the surface. The results of this study are significant for cave mines exploring sorting systems for preconcentration as they highlight how mixing can impact the variability in ore grades. [ABSTRACT FROM AUTHOR]

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Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Allyl isothiocyanate (AITC) is a soil biofumigant used for controlling soil‐borne pests that reduce the growth, quality, and yield of food crops. Its effectiveness against pathogens depends largely on its distribution in the soil, which is influenced mainly by the soil water content and application method. The distributions of AITC when injected with different moisture content or drip‐irrigated into soils were compared. RESULTS: AITC injected at 50 g m−2 only diffused 10 cm deep in soil column with 5, 10 or 15% soil moisture content. The gas AITC peak concentration was 0.64 μg cm−3 at 5% moisture content. Diffusion was reduced when moisture content increased to more than 15%. The results of adsorption kinetics and release indicated that AITC's limited distribution was due to its low vapor pressure. AITC applied by drip irrigation at 7.5 g m−2 diffused 15 cm laterally and 30 cm deep where it reached concentrations of 0.022 μg cm−3 and 0.035 μg g−1, respectively. Some soil‐borne pathogens, nematodes and weed seeds closed to the point of AITC release were effectively controlled under drip irrigation, but efficacy decreased with increased distance. AITC applied by drip irrigation at 7.5 g m−2 and covered with PE film for 5 days provided a satisfactory efficacy against soil‐borne pathogens and weeds without any phytotoxicity. CONCLUSION: Our results indicated that AITC applied by drip irrigation was more effective than injection, which will guide applicators on methods to optimize the application of AITC for efficient control of key pests and weeds. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Rapid urban expansion and climate change often bring about loess cave disasters on the Chinese Loess Plateau. It is believed that human activity and rainfall can synergistically alter the hydrogeological conditions and further accelerate the formation of loess caves. However, thus far, few cases or lines of evidence have been reported to support this conclusion. The study provided an example of the formation of loess caves in Weinan city, Loess Plateau, Northwest China, which was related to rainfall and erosion due to pipe breakage and leakage. The precipitation data were collected to examine the effect of rainfall erosion. Moreover, through a field investigation and multi-channel analysis of surface waves (MASW) survey, ten loess caves that were adjacent to aging underground pipes were systematically investigated. The physical and mechanical properties that were affected and unaffected by the loess caves were compared to explore the influence of the pipe breakage and leakage, i.e., the water content, void ratio, and self-weight collapsibility coefficient. The results showed that the spatial variation in these properties could reflect the alteration of the loess caves under the combined action of rainfall and pipe-breakage and leakage erosion. We shed light on this synergistic effect on loess cave formation and proposed a four-stage formation model: formation of the upper negative relief, initiation of the inner cave, upper to lower coalescence, and volume enlarging. New insights were provided on the development process of the loess caves and the synergistic role between human activities and a natural force. The findings can help us to more comprehensively understand the formation mechanisms and development trends of the loess caves to predict and prevent loess cave disasters on the Chinese Loess Plateau. [ABSTRACT FROM AUTHOR]

Karst aquifers are vulnerable to contamination, especially in the context of heavy rainfall events. Contamination is often associated with turbidity that can originate from the soil zone, infiltrating surface waters or resuspension of previously deposited sediments within the aquifer. While turbidity events can be well monitored at karst springs, related information about the sediment origin and the spatiotemporal input function usually remain unknown. Thus, the mobility and attenuation of the particulate matter and associated pollutants can hardly be determined quantitatively. A tracer test with suspended cave sediments and solute tracers for comparison has hence been performed in a karst aquifer at the Blue Spring (Blautopf) in Southern Germany. The tracers were injected in the cave system, at the beginning of a fully phreatic karst conduit, and monitored at the spring after a travel distance of 1250 m. The particle‐size distribution was monitored using a particle counter and sediment samples were filtered with 0.45‐μm cellulose acetate filters. Particles on the filter were analysed for major and trace elements as well as rare earth elements (REE) by ICP‐MS after acid digestion. Results show that (1) sediment particles were transported faster than solutes, which was interpreted as a transport in the main flow path of the conduit, whereas conservative tracers tend to diffuse into smaller fissures as well. (2) All measured particles sizes were transported at similar flow velocities. (3) A transport associated to sediment particles could be shown for all measured elements. This study presents a methodological improvement of comparative sediment tracer tests as well as deeper insights into particle and element transport processes in karst aquifers, originating from previously deposited cave sediment. Results provide deeper knowledge into transport processes of sediment‐associated contaminants, such as heavy metals which may strongly be affected by the particle size. This knowledge contributes to a better management of karst water resources in the context of turbidity events. [ABSTRACT FROM AUTHOR]

El Olivo Cave (Pruvia de Arriba, Llanera, Asturias, Spain) is a small karst cave located in the Aboño River basin and formed in the Cretaceous limestone of the Mesozoic cover of the Cantabrian Mountains (north of the Iberian Peninsula). It contains an important upper Pleistocene sedimentary, archaeological, and paleontological record, with abundant technological evidence and faunal remains. The archaeological record shows a first occupation that could correspond to the Middle Paleolithic and a second occupation in the Middle Magdalenian. The stratigraphic sequence inside and outside the cave was studied with geoarchaeological methodology. In this paper, the lithostratigraphic sequence is analyzed, and the data from the granulometric, mineralogical, edaphological, and radiometric analyses are presented. The results of these analyses enable an accurate interpretation of both the lithostratigraphy of the deposit and the processes responsible for its formation and subsequent evolution. The available numerical dates allow us to locate the first sedimentation episode in the cave in OIS 7a, in the Middle Pleistocene, the base of the outer fluvial sedimentation in the cold OIS 3a stage of the Upper Pleistocene and the Magdalenian occupation in the Last Glacial Maximum (OIS 2) at the end of the Late Pleistocene. [ABSTRACT FROM AUTHOR]

The paper focuses on the Pleistocene deposits in Perspektywiczna Cave, southern Poland, related to cave hyena (Crocuta crocuta). We used direct radiocarbon dating of hyena fossils supported by genetic and stable isotope analyses to infer the paleobiology of this population. Radiocarbon dating of 19 hyena remains suggests long inhabitation of the region during early MIS 3, around 50–34 ky cal BP. The youngest among our dates, 34,355–33,725 cal BP (1σ, combined of two dates for the same specimen) points out the latest appearance of a cave hyena north to Carpathians. Beside this long period of occupation, the Perspektywiczna Cave hyenas stayed ecologically stable, but their genetic structure changed. Two mtDNA haplogroups were present, one typical for other Late Pleistocene European populations and the other one known so far only from recent African populations. [ABSTRACT FROM AUTHOR]

Carbonic acid and sulfuric acid speleogenesis describe a dichotomy between epigenetic and hypogenetic caves and carbon and sulfur cycling in karst, but do not acknowledge the global spectrum of cave formation. This paper, part one of a two-part investigation, tests and revises speleogenetic models from a classic karst landscape using dissolved ion concentrations δ13CDIC, and δ34S in water samples collected at four sites across the Bluespring and Lost River karst basins in the Mitchell Plateau, Indiana, USA. Analyses revealed elevated sulfur in both karst basins but differently sourced; H2S (δ34S = −14.2‰) evolved from petroleum seeps in Bluespring Caverns accounted for up to 61% of sulfur in the cave stream, while evaporite beds (δ34S = [+14.50‰, +17.91‰]) of the St. Louis Limestone contributed up to 100% of sulfur at Orangeville Rise, a terminal spring of the Lost River karst basin. These results have implications for carbon–sulfur cycle linkages, particularly the potential acceleration of carbon flux from sulfuric acid dissolution in otherwise epigenetic settings. We suggest a new paradigm for speleogenesis in the North American midcontinent—speleogenesis in the Mitchell Plateau and similar settings is not epigenetic or hypogenetic, but instead polygenetic with competing chemical processes varying across space and time. [ABSTRACT FROM AUTHOR]

To study the effect of soil water and salt environment factors on the root growth of cotton under different moisture control, three different emergence water volumes（60, 105, and 150 m³/hm²）, two different frequencies（high frequency and low frequency） and one double film cover winter irrigation control treatment（CK: 2 250 m³/hm²） were set up to analyze the spatial distribution patterns of soil water and salt environment and root density in dry sown and wet emerged cotton fields under diffe-rent moisture control conditions. The results show that the soil water content and water infiltration range gradually become larger with the increase of seedling water quantity, and the larger the seedling water quantity, the higher the soil water content. With the same seedling water quantity, the soil water content of the high-frequency（HF） treatment becomes obviously larger. The soil conductivity of each treatment tends to decrease gradually with the increase of seedling water and drip frequency, among which the distribution of soil conductivity of S6 treatment is closest to that of CK. With the increase in soil depth, the soil conductivity tends to increase first and then decrease. Compared with the low-frequency（LF） treatment, the high-frequency treatment shows a significantly deeper soil salt accumulation layer. The root length density（RLD） of cotton gradually increases with the amount of seedling water and the frequency of dripping. The soil layer of root distribution gradually deepens with the amount of seedling water in the vertical direction, and the RLD value in the horizontal direction is significantly greater in the mulched area than that in the bare area between films. This research can serve as a solid scientific foundation for the use of dry sowing and wet emergence techniques in cotton fields in southern Xinjiang. [ABSTRACT FROM AUTHOR]

DNA barcoding represents a handy tool for species identification. In addition, it serves as a complementary approach that improves the characterisation of evolutionary lineages and facilitates the detection of potentially undescribed and cryptic species. Based on the case study in the Western Carpathians, which belong to the Carpathian biodiversity hotspot, we have compiled the first DNA barcode reference library for molecular identification of invertebrates associated with epikarst, a unique, yet understudied, shallow subterranean aquatic habitat that extends at the interface between the soil and carbonate rocks. We analysed invertebrates collected in 2019-2020 from epikarst water that continuously seeps into four caves of the Demänovský Cave System in northern Slovakia. The standard barcode marker of the mitochondrial COI gene was amplified in more than 920 individuals of aquatic, semi-aquatic, and terrestrial invertebrates. The final data set consisted of 784 barcode sequences representing 36 morphospecies, the majority (98.3%) belonging to Arthropoda. Automated cluster delineation using the Barcode of Life Data System (BOLD) revealed 60 Barcode Index Numbers (BINs), of which 43 BINs were new to BOLD, representing mostly typical subterranean species. Almost 20% of the morphospecies displayed high intraspecific variation (>2.2%), suggesting the need for further investigation to assess potential taxonomic problems or cryptic diversity. Our results also indicated the existence of several yet undescribed invertebrate species and possible heteroplasmy or COI numts in the collembolan Megalothorax sp. (incertus species group). The resulting DNA barcode library represents a significant advance not only in the characterisation of epikarst biodiversity but also in the understanding of subterranean biodiversity in general, paving the way for future complex evolutionary and biogeographical studies. [ABSTRACT FROM AUTHOR]

The Prokletije Mountains/Albanian Alps are the highest part of the Dinaric Mountains. Paradoxically, these mountains and their cave areas remain among the most enigmatic in Europe, having only recently become subjects of scientific research and cave exploration. This paper focuses on the Kolata and Greben massifs, where the highest, and thus the oldest, cave systems are located. Through the analysis of heavy mineral composition, the apatite-tourmaline index, and cluster analysis for mineralogical composition and uranium isotopic data, it becomes possible to identify the source areas for the cave clastic deposits. It also allow to distinguish multiple paleoflow directions, each corresponding to different stages of cave development. The older paleoflow was probably from south to north, whereas the younger one is inferred to have flown from east to west. The change in the paleodirection of sediment transportation was probably caused by Neogene tectonic movements. In the later period, because of the subsequent uplift of the Prokletije Mts. and their fragmentation into individual massifs, the transport to the caves was local and related to deglaciations. The deposition of the speleothem from the oldest caves of the Prokletije Mts. took place in the periods c. 381 and 308 ka (MIS 11 and MIS 9), which suggests that these levels had already passed from the phreatic to the vadose stage. Considering the morphology of the caves studied, we believe that these caves may have begun to form at least in the Middle Pleistocene. There are two generations of younger speleothems first at 163 ± 4 ka (MIS 6) and second from 92 ± 2 to 39.4 ± 2 ka (Weichselian age).

At the Last Glacial Maximum (LGM), records suggest drier conditions in the northwest United States and wetter conditions in the southwest United States relative to present-day as well as widespread changes in the isotopic composition of water. However, the mechanisms responsible for these changes remain ambiguous. Here, we explore differences in western United States hydroclimate between the LGM and preindustrial with a water isotope tracer enabled Earth System Model. We then use proxy forward models to compare simulated and recorded δ18O in speleothems. We find that the pattern of hydroclimate response in the western United States at the LGM relates to a combination of 1) increased frequency and southward shifted wintertime extratropical cyclones in the North Pacific, 2) greater rainout of moisture as it moves over the continent, and 3) reduced evaporation in the cooler LGM climate. The simulated lower δ18O of precipitation at the LGM relates predominantly to an increase in cool season moisture removal efficiency, with a secondary contribution from relatively more cool season precipitation. Both surface temperatures and North American ice sheets contribute to these hydroclimate changes at the LGM. Comparisons between δ18O from proxy forward models and speleothem records in the western United States show general agreement at the LGM, with increasing depletion moving towards the continental interior. This study highlights the similarities and differences between hydrologic and δ18O changes at the LGM and emphasizes the utility of model-proxy comparison for interpretation.

Àngel Ginés was a highly respected scientist and speleologist who dedicated his career to the study and dissemination of karst knowledge. He explored unknown caves in Mallorca in the late 60s and collaborated with local and international speleological communities throughout his career. He published numerous scientific articles and authored reference books on karst, and also served as a teacher and professor in biology and geology. His sudden passing is a great loss to Mallorcan speleological research. The provided text includes a list of references to scientific articles and books written by Àngel Ginés and his colleagues, covering topics such as sea-level changes, radon surveys in caves, karst development, and the impact of deforestation on karst terrains. These publications offer valuable insights into the geological and environmental history of Mallorca and are a valuable resource for researchers studying these topics. [Extracted from the article]

The carbon isotopic composition of dissolved organic carbon (δ13CDOC) in speleothems, based on high-precision U-Th ages, has great potential to reconstruct past ecology, microbial activity, and carbon cycling. Identifying the reliability of the pretreatment and measurement of speleothem δ13CDOC is therefore essential to putting it into practice. Actually, we have previously verified the reliability of the method for speleothem δ13CDOC measurements. However, it was only based on the final δ13CDOC values of homogeneous speleothem powder and is unable to evaluate the effects of different experimental conditions and the impacts of adding acid on δ13CDOC if using speleothem as the study samples. In this study, we used an organic reagent (potassium sorbate) as the study sample and designed a conditional experiment that simulates the protocols for speleothem δ13CDOC analysis and presented the resulting data to inspect the effects of the experimental processes on the analysis of δ13CDOC. The results show that the standard deviation of duplicate samples is 0.1‰, which is close to that of the previous work for organic reagents and water samples, and the results were not affected by different experimental conditions and operation steps (such as adding orthophosphoric acid, digestion time, and storage duration of resulting CO2 in storage vessels), suggesting that this method is robust to detect the speleothem δ13CDOC. Considering the range and standard deviation of results, we proposed that the δ13CDOC record could be used in various studies when the amplitudes of the δ13CDOC record are larger than 0.1‰, especially greater than 0.4‰.

The article highlights the significance of well-preserved perishable organic materials, such as wood, plant fibers and skins, in studying past societies and understanding human adaptations, technology and ecological knowledge. It specifically examines the plant-based artifacts found in Cueva de los Murciélagos, providing insights into the evolution of plant-based technologies during the Early-Middle Holocene in Europe, shedding light on cultural traditions.

In this paper, we described fossils from six mammal taxa (Coendou magnus Cuvier, 1823; Nothrotherium maquinense (Lund, 1839); Tamandua tetradactyla (Linnaeus, 1758); Leopardus wiedii (Schinz, 1821); Didelphis sp.; and Dicotyles tajacu (Linnaeus, 1758)) found in Toca da Barriguda cave (Campo Formoso, Bahia, Brazil). To better understand the isotopic paleoecology of these taxa, AMS radiocarbon dating and carbon and oxygen isotopic analyses were performed. The radiocarbon ages indicate the occurrence of Condou magnus at 33,171–33,765 Cal yr BP, Tamandua tetradactyla at 43,944–44,496 Cal yr BP, Leopardus wiedii at 45,475–46,157 Cal yr BP, and Didelphis sp. at ∼50,227 cal yr BP. Of these taxa, five were carnivorous/omnivorous, only Coendou magnus was herbivorous and lived in low-density forest and arboreal savanna habitats (δ 13C = −12.8‰ to −8.4‰; p i C 3 = 80–90%) during the late Pleistocene. An increase in a dry climate in the region between 50 cal kyr BP (δ 18O = 27.1‰) and 27 cal kyr BP (δ 18O = 34.0‰) was suggested based on the oxygen isotopic values found in the mammalian bone fossils, which presents similarity and good correlation with the oxygen isotopic values recorded in stalagmites from two caves in Brazil. [ABSTRACT FROM AUTHOR]

In order to comprehend the dynamic disaster mechanism induced by overburden rock caving during the advancement of a coal mining face, a physical simulation model is constructed basing on the geological condition of the 21221 mining face at Qianqiu coal mine in Henan Province, China. This study established, a comprehensive monitoring system to investigate the interrelations and evolutionary characteristics among multiple mechanical parameters, including mining-induced stress, displacement, temperature, and acoustic emission events during overburden rock caving. It is suggested that, despite the uniformity of the overburden rock caving interval, the main characteristic of overburden rock lies in its uneven caving strength. The mining-induced stress exhibits a reasonable interrelation with the displacement, temperature, and acoustic emission events of the rock strata. With the advancement of the coal seam, the mining-induced stress undergoes four successive stages: gentle stability, gradual accumulation, high-level mutation, and a return to stability. The variations in other mechanical parameters does not synchronize with the significant changes in mining-induced stress. Before the collapse of overburden rock occurs, rock strata temperature increment decreases and the acoustic emission ringing counts surges with the increase of rock strata displacement and mining-induced stress. Therefore, the collaborative characteristics of mining-induced stress, displacement, temperature, and acoustic emission ringing counts can be identified as the precursor information or overburden rock caving. These results are in good consistent with on-site situation in the coal mine. [ABSTRACT FROM AUTHOR]

In this article, we present the results for an analysis of charcoal remains from Klasies River main site cave 1. The analysis was done to understand the environmental conditions of the Tsitsikamma Coast during the late Holocene, approximately 2300 cal BP. A high-resolution reflective light microscope (Olympus BX51) with up to 500X magnification was used to analyse the microanatomy of archaeological and comparative wood charcoal, as well as following standard Anthracology procedures. Common woody species from the contemporary Klasies River landscape along with many others from other parts of southern Africa were used to identify archaeological charcoal samples to species. The vascular structures of archaeological and contemporary woody species from Klasies River were also measured and compared so that wood Vulnerability Indices could be calculated. Two species, Protorhus longifolia and Hibiscus cf. tiliaceus, from the archaeological charcoal assemblage indicate that environmental conditions in the Tsitsikamma Coast are no longer suited for their growth. These species currently grow in the east coastal areas and minimally in the eastern highlands of southern Africa where they tolerate a warm climatic setting. Overall, the taxonomic results indicate that more than 80% of the 17 archaeological species identified here are adapted to year-round and summer rainfall conditions. This is in contrast with the present environmental setting at Klasies River that includes, predominantly, species that prefer year-round and winter rainfall with fewer summer rainfall adapted species. A comparison of the vascular structure of the archaeological woody species against that of contemporary species indicates that the archaeological Klasies River landscape received relatively higher rainfall levels in the Late Holocene than it does presently. We conclude that the Klasies River landscape, located in the year-round rainfall region of southern Africa, supported differing amounts of winter and summer rainfall-adapted woody vegetation through time. During the late Holocene, c. 2300 cal BP, environmental or climatic conditions were more favourable for summer rainfall-adapted woody species to thrive better than at present. The same woody vegetation was also less adapted to aridity than that found in the area today. [ABSTRACT FROM AUTHOR]

Hydraulic fracturing is an efficient technology to extract hydrocarbon within natural caves. However, these caves can markedly affect the fracture propagation behavior. This paper proposes a novel hydraulic fracturing model to simulate the fracture propagation in poroelastic media containing the natural cave, utilizing the strengths of the phase-field method. By coupling the Reynolds flow with cubic law in fracture domain, free flow in cave domain, and low-permeability Darcy flow in reservoir domain, the fracture-cave-reservoir flow governing equations are established. The Biot poroelasticity theory and fracture width are the links of hydro-mechanical coupling. The smooth phase-field is introduced to diffuse not only the sharp fracture but also the sharp cave edge. The fully coupling model is solved by a staggered scheme, which independently solves the pressure field and displacement field in inner cycle, and then independently solves the phase field in outer cycle. The proposed model is verified by comparing with the Khristianovic–Geertsma–de Klerk (KGD) model and Cheng's hydraulic fracturing model. Then, the interaction between hydraulic fracture and natural cave is investigated through several two-dimensional and three-dimensional cases. The result shows that the cave effect can make the hydraulic fracture deflect and raise its propagation velocity. Increasing the fracture-cave distance, injection rate, and in situ stress difference can all decline the cave effect. The displayed cases also substantiate the capability and efficiency of the proposed model. [ABSTRACT FROM AUTHOR]

We inferred the annual isotopic diet (δ13C) of an individual of the giant ground sloth Eremotherium laurillardi found in Toca dos Ossos (Ourolândia, Bahia, Brazil) through the extension of its third inferior molar. This individual lived in the region at 40,779-39,617cal yr BP. One year of its life was recorded in a length of 67 mm in the tooth. Two years were recorded in this molariform, during which the diet and climate did not change much, and substantial precipitation occurred during the middle of the year, which is in opposition to the modern pattern. The mean carbon (μδ13C=-13.9 ± 1.8‰) and oxygen (μδ18O = 22.5 ± 2.9‰) isotopic values were similar to values for other individuals of the species found in the same cave but different from the values found in other localities of the Brazilian Intertropical Region, which allows us to suggest that this region had more precipitation and lower temperatures in comparison to today. The oxygen isotopic values found in dated fossils of E. laurillardi and from two other taxa found in the same cave (Toxodon platensis, and Notiomastodon platensis) could help in the understanding of the climatic variation that occurred in the region. [ABSTRACT FROM AUTHOR]

Karst cave was revealed in the construction of the Laobishan Tunnel of the new Chengdu-Kunming Railway, involving the risks of falling blocks from the top of the cave and flooding by karst water pouring backwards, which needs appropriate crossing scheme. Some investigation methods were used to determine the type of karst cave, and a scheme of arch bridge with protective structure was proposed to cross the karst cave, with specific structural design. To support the engineering design of the arch bridge and the retaining bridge structure, the three-dimensional space simulation analysis model of the bridge structure was established by using the finite element method. For the construction stage and the completion stage, the static performance of the main arch ring of the arch bridge was systematically analyzed from the angles of deformation and stress, and the strength and cracks of the most unfavorable section under stress were discussed. Results show that, the water supply in the karst cave is mainly bedrock fissure water, and the karst cave is stable. At the stage of construction, the maximum compressive stress and maximum tensile stress of the main arch ring are 5.94 MPa and 2.74 MPa respectively, and the position of occurrence is at the lower and upper edge of the arch foot of the main arch ring. At the stage of completion, the midspan arch crown section and arch foot section are the most unfavorable section positions under different load combinations. The maximum normal stress of concrete and reinforcement are 11.88 MPa and 189.07 MPa respectively, and the maximum width of crack is 0.19 mm. The stress and crack meet the requirements of relevant specifications. [ABSTRACT FROM AUTHOR]

Caves evolution is controlled by lithological properties, discontinuities, water, climate, and physicomechanical properties of soluble rocks, vegetation and human impact. This study investigates the cave formation in Upper Miocene-Pliocene clastic rock in Menteşe town of Muğla. The lithology, physico-mechanical properties and hydrogeologic factors of host rocks and morphology of the caves in Asar Hill and Damlam Stream valley were examined. The caves are 1.47-9.71 m long, 2.24-19.36 m wide and 1.38-27 m high. Four joint sets and bedding planes affect the clastics in the Asar Hill area. Mudstones (low plasticity clay, sandy clay) are in soft-very soft rock, while conglomerate is in moderate-hard rock class. The mudstone removal has started the formation of the caves. The vegetation roots act as groundwater circulation paths in the Damlam Stream area. Water has eroded mudstone and muddy matrix of conglomerate following cracks and led to the formation of the caves. Water infiltration may have led to stalactite, flowstone and travertine formation in Damlam Stream caves. Possible cave collapse could threaten life and property in the Asar Hill area, and may cause the destruction of internal structures of the caves in the Damlam Stream. Thus, precautionary measures such as continuous monitoring and protection must be taken in both cave areas. [ABSTRACT FROM AUTHOR]

The southern coast of South Africa displays a highly dynamical climate as it is at the convergence of the Atlantic and Indian oceans, and it is located near the subtropical/temperate zone boundary with seasonal influence of easterlies and westerlies. The region hosts some key archeological sites with records of significant cognitive, technological and social developments. Reconstructions of the state and variability of past climate and environmental conditions around sites of archeological significance can provide crucial context for understanding the evolution of early humans. Here we present a short but high-resolution record of hydroclimate and temperature in South Africa. Our reconstructions are based on trace elements, calcite and fluid inclusion stable isotopes, as well as fluid inclusion microthermometry, from a speleothem collected in Bloukrantz cave, in the De Hoop Nature Reserve in the southern Cape region of South Africa. Our record covers the time period from 48.3 to 45.2 ka during marine isotope stage 3. Both δ18 O c and δ13 C c show strong variability and covary with Sr/Ca. This correlation suggests that the control on these proxies originates from internal cave processes such as prior carbonate precipitation, which we infer to be related to precipitation amount. The hydroclimate indicators furthermore suggest a shift towards overall drier conditions after 46 ka, coincident with cooling in Antarctica and drier conditions in the eastern part of South Africa corresponding to the summer rainfall zone (SRZ). Fluid inclusion-based temperature reconstructions show good agreement between the oxygen isotope and microthermometry methods, and results from the latter display little variation throughout the record, with reconstructed temperatures close to the present-day cave temperature of 17.5 ∘ C. Overall, the BL3 speleothem record thus suggests relatively stable temperature from 48.3 to 45.2 ka, whereas precipitation was variable with marked drier episodes on sub-millennial timescales. [ABSTRACT FROM AUTHOR]

Shelter caves serve as crucial repositories that provide valuable insights into Late Pleistocene–Holocene depositional mechanisms and environmental changes. In this study, we conducted a stratigraphic analysis of the easternmost cave-fill succession within the Santuario della Madonna cave, located along the Tyrrhenian coasts of southern Italy. By examining the cave-fill deposits and their relationship with archaeological successions from previous excavation campaigns, we aimed to enhance our understanding of sedimentary evolution, specifically, the interplay between local and global environmental factors. A comprehensive sedimentological analysis was conducted, enabling the identification of three distinct sedimentary facies within the clastic succession that overlays the calcareous cave roof. Our findings reveal a noticeable shift in cave sedimentation processes, characterized by a gap in detritus accumulation followed by the deposition of flowstones. Furthermore, the presence of oversized boulders within the succession was attributed to failures from the cliffs that overhang the cave opening. We interpret these boulders as possible evidence of cave collapses induced by earthquakes, similarly to rockfall phenomena observed in the archaeological test pits within the shelter, which show a strong correlation with paleoseismic events. [ABSTRACT FROM AUTHOR]

We integrate 10 new with five published 40Ar/39Ar age determinations, both on primary volcanic deposits and on detrital sanidine, which provide precise geochronologic control on the Marine Isotope Stage (MIS) 5.5 and MIS 5.3 sea‐level indicators that occur at three coastal caves in a tectonically stable region of the central Tyrrhenian Sea of Italy. The age of a Strombus‐bearing bioclastic conglomerate, associated with a tidal notch occurring at 9.5 m a.s.l. at Cape Circeo, is constrained to between 121.5 ± 5.8 and 116.2 ± 1.2 ka. Moreover, backbeach deposits intercalated in the sedimentary filling of Guattari and Capre coastal caves are directly correlated with a tidal notch at ∼2.5 m associated with another bioclastic conglomerate at Cape Circeo and dated to 110.4 ± 1.4–104.9 ± 0.9 ka. The latter deposit is also correlated with the adjacent marine terrace, occurring at 3–5 m on the coast between Capes Circeo and Anzio, for which a maximum age of 100.7 ± 6.6 ka was previously reported. These data provide evidence for a maximum sea level around 9.5 m above the present sea level and a duration of MIS 5.5 highstand until 116 ka, in agreement with estimates from other regions in the world. In contrast, they suggest a maximum sea level during MIS 5.3 highstand that is similar to the present level, and only ∼7 m lower than the MIS 5.5 highstand, challenging the reconstructions of the MIS 5 ice‐sheet volumes and derived global sea levels that are based on benthic oxygen isotope records. Key Points: We present 10 40Ar/39Ar ages on the Marine Isotope Stage (MIS) 5.5 and MIS 5.3 sea‐level indicators on the Tyrrhenian Sea coastMIS 5.5 paleo‐sea level at ∼9.5 m a.s.l. is dated 121.5 ± 5.8 through 116.2 ± 1.2 kaWe find a MIS 5.3 sea level ca. 20 m higher than the δ18O‐derived values [ABSTRACT FROM AUTHOR]

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Sandy dolomite, being a soluble rock, is prone to dissolution and erosion caused by groundwater, leading to the formation of underground caves and fractures. This may result in geological disasters such as ground subsidence and collapse. In this paper, the changes and mechanical properties of black sandy dolomite after hydrochemistry are studied. A semi-immersion test with different concentrations of iron sulfate solution was carried out to simulate the water-rock interaction in different water environments. After that, scanning electron microscope (SEM) results could reflect the dissolution and pore development of rock by the effect of water-rock interaction from the microscopic. Water-rock interaction enlarges cracks in rocks and dissolves pyrite, carbonate minerals, and other components, reducing the cementation between particles. The change in the mechanical properties of black sandy dolomite under water-rock chemical interaction was revealed by uniaxial compression test. The mechanical properties of the samples exhibit varying degrees of deterioration, with strain increased ranging from 4.96 to 29.58%. The brittleness index modified (BIM) values for each sample ranged from 5.20 to 6.20%, all of which are larger than 4.70% in the natural state. [ABSTRACT FROM AUTHOR]

In order to reveal the community characteristics and trophic structure of oribatid mites in different moss habitats in karst caves, the oribatid mites in the moss habitats of ground (GD), understory (US), cave wall (CW), surface shrub (SB) and farmland (FL) outside the cave were collected in October 2021. Through the identification and data analysis of oribatid mites, 2352 oribatid mites were found, belonging to 45 families and 72 genera, most of which were Gymnonota. The family number, genus number, individual number, individual density, dominant genus composition, community diversity, community similarity, MGP (Analysis methods for ecological groups of oribatid mites) ecological group of oribatid mites and trophic structure of oribatid mites in different moss were analyzed. The results showed that: (1) The number of families, genera, individuals, and individual density of SB and FL are higher than those of the other three habitats; (2) Platyliodes, Oppiella, Tectocepheus, Scutovertex, Scheloribates and Trichogalumna are the dominant genera of the oribatid mites in the cave moss habitat, among them, Tectocepheus and Trichogaluna have the most obvious advantages; (3) The diversity index of shrub (SB) was higher than that of other four habitats; Similarity between ground and cave wall, shrub and farmland is high; (4) The MGP ecological group of oribatid mites in different habitats is dominated by O type (Overall type belongs to MGP analysis results, 20%≤M,G,P≤50%), and a total of 42 genera of oribatid mites preliminarily constitute the trophic structure of oribatid mites in the cave moss habitat. Based on the above results, it can be concluded that there are differences in the community structure of oribatid mites in different moss habitats in the study area, and the use of dominant genera of mites can preliminarily indicate the environmental conditions of different moss habitats. This study enriches the study of mites in karst cave mosses, and can provide theoretical significance for the protection of cave biodiversity in karst areas. [ABSTRACT FROM AUTHOR]

Complex patterns of acoustic communication exist throughout the animal kingdom, including underwater. The river-dwelling and the Pachón cave-adapted morphotypes of the fish Astyanax mexicanus are soniferous and share a repertoire of sounds. Their function and significance is mostly unknown. Here, we explored whether and how sounds produced by blind cavefishes inhabiting different Mexican caves may vary. We compared "Clicks" and "Serial Clicks" produced by cavefish in six different caves distributed in three mountain ranges in Mexico. We also sampled laboratory-bred cavefish lines originating from four of these caves. Sounds were extracted and analyzed using both a manual method and a machine learning-based automation tool developed in-house. Multi-parametric analyses suggest wild cave-specific acoustic signatures, or "accents". An acoustic code also existed in laboratory cavefish lines, suggesting a genetic basis for the evolution of this trait. The variations in acoustic parameters between caves of origin did not seem related to fish phenotypes, phylogeography or ecological conditions. We propose that the evolution of such acoustic signatures would progressively lead to the differentiation of local accents that may prevent interbreeding and thus contribute to speciation. [ABSTRACT FROM AUTHOR]

The present study focuses on the microvertebrate fossil material retrieved from the three fossiliferous units of Kalamakia cave dating from ca. 90–25 kya BP, to identify the accumulation agents of the assemblage and the processes that affected it post-depositionally. This was done through the quantification of specific indices described in the literature concerning breakage, digestion and other types of modifications observed upon the surface of the specimens. Furthermore, the Taxonomic Habitat Index was calculated to reconstruct the possible habitat types in the surrounding area. Regarding the results on taphonomy, significant amounts of post-depositional breakage were observed, possibly resulting from trampling and, secondarily, modifications from the occasionally naturally occurring high humidity within a cave. The main accumulators of the microvertebrate assemblage seem to have been barn owls either independently or jointly with long-eared owls and/or owlets. Concerning the habitats possibly present in the area, the existence of mixed habitats varying between relative expansions of shrublands, grasslands, rocky areas and (limited) deciduous forests was identified, while the occasional presence of water bodies was also revealed. Shifts between the percentages of different habitats were not great but could be correlated with climatic events within a geochronological context. [ABSTRACT FROM AUTHOR]

China is a country short of water resources, and improving the water use efficiency (WUE) in agriculture has become the only way to ensure sustainable development. In this article, subsurface drip irrigation (SDI) experiments of cucumber were implemented with a randomized block design comprising two factors and three levels, and the two factors were depth of drip belt buried and irrigation amount, which were determined by a 20 cm diameter pan's water evaporation times its coefficient (Kp). The effects of schedule of SDI on soil evaporation (Es), evapotranspiration (ET), Kp, root dry matters, yield, and WUE of cucumber were studied. The results indicated that the Es and the ET decreased along with increasing depth of drip belt buried or decreasing amount of irrigation water applied. The relationships between ET and its total irrigation amount were significant linear positive correlations. Proportions of plant transpiration accounting for the ET were about 41~69% in two years, and it became bigger along with the increase of ET within a year. The Kp became smaller along with the reducing of ET. The roots of cucumber were mainly concentrated in the soil layer of 0~20 cm, and the two factors could only influence root dry weights of 0~60 cm soil layers significantly. The relationships between yield and ET were quadratic polynomial correlations. At last, an ultimate SDI scheduling mode based on water evaporation was established. [ABSTRACT FROM AUTHOR]

Interactions of karst aquifer sediments with organic contaminants or microplastics (MPs) have received relatively little attention even though the susceptibility of karst aquifers to contamination and their ability to store and transport sediment are well documented. Studies using polystyrene microspheres as surrogate tracers for bacteria transport in karst systems have generally observed low recovery of microspheres and attributed this to microsphere adsorption onto aquifer sediments. In addition to being used as surrogate tracers for bacteria, microspheres have the potential to be used as surrogate material for organic contaminants and MPs. Using cave sediments as a proxy for karst aquifer sediments, the adherence of two types of microspheres (carboxylated and non-functionalized) was measured in three different types of solutions: deionized water (DI), a calcium carbonate solution, and a karst spring water. Both types of microspheres adhered to the sediments; the most influential factor in adherence was solution type not microsphere type. Average adherence ranged from 51 to 94 percent with average adsorption coefficients (KD) ranging 11.8-442. Average estimated organic carbon-water partition coefficients (KOC) and retardation factors (RF) ranged from 1.64 3 103 to 6.13 3 104 and from 6.20 3 101 to 2.29 3 103, respectively. KD, KOC, and RF were an order of magnitude higher in the karst water than in DI or CaCO3 solution. The results illustrate the importance of sediment interactions with potential organic or MP contaminants in karst systems. [ABSTRACT FROM AUTHOR]