Acta Carsologica

Sediment load with metallurgical slag admixture under diverse morphological conditions along submerging karst stream

Jan Lenart, Filip Chalupka — Tue, 05 Nov 2024 00:00:00 +0100

This study investigates the clastic fluvial sediments of the Jedovnický submerging stream in the section between the Jedovnice village and Křtinský stream (Moravian Karst, Czechia). A total of 28 samples were collected to analyze clast composition, slag content, grain size, and roundness. The sediment primarily consists of allochthonous Lower Carboniferous material (greywackes, clayey shales) with varying amounts of metallurgical slag, occasionally mixed with autochthonous deposits such as rockfall accumulations and tailings from the excavation of connecting adits. The slag content fluctuates, peaking downstream of the erosive section of the Rudické propadání cave, near the Stará řeka passage connection. Grain size distribution is influenced by both surface and cave morphology, as well as hydraulic conditions. The alternation between erosive and depositional zones, along with the unique karstic and speleorelief features, plays a crucial role in clast mobilization. These features include ponors, erosive and paragenetic corridors, sumps, and rockfalls. Fine particle accumulations are particularly noticeable in front of sumps or dams. Throughout the studied section, the proportion of coarse particles (>10 mm and 5–10 mm) gradually decreases, while finer particle content increases toward the resurgence. The roundness of Carboniferous sediments remains relatively constant, although it is significantly influenced by the presence of well-rounded, weak and ductile slag clasts. Overall, both the slag content and the proportion of well-rounded and rounded clasts in the coarser fractions (>10 mm and 5–10 mm) show a decreasing trend toward the resurgence.

Assessment of diffusive recharge at regional scale in karst systems, Amazon basin, Ecuador

Tue, 05 Nov 2024 00:00:00 +0100

Karst systems play a crucial role in drinking water supply and biodiversity. Therefore, their comprehensive characterization of their recharge mechanisms is essential for safeguard water resource quality and sustainable management. This study utilizes the open-access thematic cartography of Ecuador to analyze the lithological, geomorphological, and hydrographic boundaries of groundwater karst systems. Then, employing the APLIS method, the diffusive recharge for each system is calculated. As a result, five hydrogeological karst systems and twelve small isolated karst bodies were delineated within the Amazon Region of Ecuador, collectively occupying a total area of 11112 km2. The effective infiltration of precipitation within these systems was found to vary between 11.11% and 77.11%, with a predominant low infiltration range (20%-40%) covering 48% of the karst area. One of the multiple parameters used in water balance calculations is defined by this research, serving as the initial step in creating conceptual models for evaluating karst aquifer systems in Ecuador from a hydrological perspective. The findings not only offer insights into the vulnerability and characteristics of these systems but also establish the foundation for informed decision-making in sustainable groundwater resource management and protection efforts.

Characteristics of the micropseudokarst landforms in Pâclele Mari mud volcanic area (Romania)

Janos Moga, Katalin Fehér, Daniela Strat — Tue, 05 Nov 2024 00:00:00 +0100

In this paper, we present the results of the geomorphological study of the micro pseudokarst landfoms developed on Pâclele Mari mud volcanic site that belongs to the famous mud volcanic area Berca-Arbănași, Buzău Subcarpathians, Romania. Different types of pseudokarstic cavity formation can be observed in the area, especially in the sloping periphery of the mud volcanic area, where badlands developed (badland pseudokarst), and rheogene pseudokarst in the mud flows. The liquid mud material gets denser and wimple on the surface of the mud that flows in the trough, it compiles and then covers the liquid mud channel. These micro-size covered tunnels are similarly formed as lava tubes at the lava flows of real volcanic areas. In order to complement the field measurements, we carried out surveys with a DJI Phantom 3 and 4, and Mavic Pro quadcopter to determine the landforms for the photogrammetry. Granular composition tests were carried out on sediment samples collected in the mud volcanic area by a laser diffraction particle analyser.

Cave morphology and moonmilk deposits of Ryongmun Cavern, Democratic People’s Republic of Korea: A Study for the Conservation of Natural Heritage

Won–Sok Jon, To-Jun Ryang, Hyon Hwangbo — Tue, 05 Nov 2024 00:00:00 +0100

The Ryongmun Cavern, registered on the World Heritage Tentative List, is the largest and most beautiful karst cave on the Korean peninsula. The characteristics of the cave morphology and moonmilk deposits in the Ryongmun Cavern were studied. A cross section of the main direction of the cave shows that the Ryongmun Cavern is made up mainly of four strata and this caused 4 stages of decline in underground waterline in the course of cave formation. The cave is mainly characterized by NW–SE-trending, NWW–SEE-trending and NNE– SSW-trending passages. The horizontal passages usually have large and wide spaces, whereas the inclined ones are relatively small and narrow. The cave minerals in the Ryongmun Cavern are mainly calcite and aragonite. In the cave, stalactites, stalagmites, limestone columns, cave pearls, etc. Are calcite; and, anthodites are aragonite. In the cave, speleothems display a wonderful underground landscape in harmony with the cave bedrock and groundwater (streams, waterfalls and ponds). The main scenes of the underground karst landscape in the cave are stalactites, stalagmites, limestone columns, stone waterfalls anthodites, underground waterfalls, and underground ponds.The deposits that have been formed recently on the surface of speleothems and walls in the cave are mainly moonmilk composed of hydromagnesite (Mg₅(CO₃)₄(OH)₂•4H₂O) with an average particle size of 0.55 μm and chemical composition of MgO–29.43% and CaO–6.28%. The moonmilk is present in a white, fine powder form, a hand-rubbed smooth, and a moisture content of 42.0%. Also, the pH is 10.09, which is alkaline. In the Ryongmun Cavern, moonmilk was formed at sites with very low supply of karst water and relatively high wind speeds. The unique underground karst features provide sufficient evidence for geoheritage value of the cave and the characteristics of moonmilk provide a significant implication for management and preservation of the cave environment.

Afforestation of common land in the Classical Karst: relations between the authorities, the local population, and the economic consequences of afforestation

Nikita Peresin Meden — Tue, 05 Nov 2024 00:00:00 +0100

The findings of environmental history are in the service of ecology and represent an important contribution to the understanding of the sustainable management of land. The aim of this article is to shed light on the relations between the local population and the authorities regarding the afforestation of common land in Komen in the second half of the 19th century and the beginning of the 20th century, placing them in a broader Mediterranean context. The local population was not opposed to afforestation per se, but to the prohibition of usufruct on afforested land, which had major economic consequences for the local population. Authorities did not always take into consideration the annual agricultural processes, local customs, and natural resource needs in their afforestation decisions. The prohibition of usufruct was followed by a shortage of fodder and firewood, which led to forest violations to satisfy demands. Thus, afforestation has undermined the basis of agriculture. In addition, already afforested land remained under common ownership for a relatively long time.

The diversity and morphology of the genus Luticola D.G.Mann (Bacillariophyta) from subaerial biofilms of caves in Serbia

Tue, 05 Nov 2024 00:00:00 +0100

Research of cave-dwelling diatoms is lacking. In these extreme environments, diatoms are restricted to illuminated zones, and are found at the entrance zone and in the lampenflora community. However, the number of identified species is constantly increasing, and new species are being discovered. The genus Luticola is one of the most widely studied genera worldwide and many representatives are characterized as aerophilous and are found in terrestrial habitats. For the first time, Luticola species identified from phototrophic subaerial biofilms of 10 caves in Serbia (cave entrances and lampenflora) based on detailed light microscopy (LM) and scanning electron microscopy (SEM) observations were summarized and discussed. In total 11 representatives of the genus were identified at the species level, and morphological features of Luticola acidoclinata, L. angusta, L. frequentissima, L. dismutica, L. nivalis, L. triundulata, and L. quinquenodis were characterized in detail. For Luticola angusta, electron microscopy images are shown for the first time. Additionally, four new taxa (L. angusta, L. frequentissima, L. kopanjae, and L. poulickovae) were recorded for the diatom flora of Serbia. The study fills an important gap regarding the occurrence and characteristics of Luticola representatives in subaerial habitats.

Interview with Professor Colin Murrell

Janez Mulec — Tue, 05 Nov 2024 00:00:00 +0100

Prof. Colin Murrell, a distinguished microbiologist and Emeritus Professor at the University of East Anglia, UK, is well known for his contributions to various areas of environmental microbiology and microbial ecology. Prof. Murrell has received several awards, including election to membership of the European Molecular Biology Organisation, the European Academy of Microbiology, the Chinese Academy of Sciences Distinguished Professor (Einstein) Award. He was awarded a highly prestigious European Research Council Advanced Grant and has been member of many editorial boards of leading microbiological journals including Environmental Microbiology and the ISME Journal. He has graduated over 60 PhD students and supervised around 150 researchers throughout his career. His research interests are immense, extending from the development of analytical tools in molecular microbial ecology to their testing in the field, which is reflected in his extensive publication list of over 350 highly cited papers in prestigious journals. His pioneering research has significantly improved our understanding of microbial processes in diverse environments, from soil to aquatic and marine ecosystems. More recently, he has extended his scientific curiosity to karst and caves, in particular to the Movile Cave in Romania, which represents a cornerstone for understanding the role of chemolithoautotrophy in caves.