The article discusses avalanche occurrence in the Slovenian Alps (SE Alps) in the context of climate change. It analyses the relationship between the North Atlantic Oscillation and maximum snow depth ...over the last two centuries, and the relationships between maximum snow depth and avalanches over the last three decades. We argue that higher temperatures lead to precipitation in the form of rain at higher elevations even in winter, so that major wet avalanches occur already in winter rather than in early spring, as was more common in the past. A case study of extreme avalanches in January 2021 is presented to support the hypothesis.
The study of tourism carrying capacity in the municipalities of Tolmin, Kobarid and Komen has shown that the infrastructural and economic carrying capacity is the most problematic, as most indicator ...limits are already exceeded in the summer season. The most favourable is the spatial-ecological carrying capacity, where none of the studied indicator limits were exceeded. The results of the carrying capacity assessment for tourism in these municipalities should not be used as a tool to restrict tourism development, but rather as expert recommendations to promote more sustainable tourism development. Infrastructure identified as deficient cannot be improved immediately. Improvements require large financial investments that municipalities are not able to ensure quickly. We need a tourism development strategy that, in addition to all the necessary improvements, comprehensively addresses the problems that municipalities face from overtourism, especially during the high season.
We conducted a phytosociological study of the communities hosting the rare and endangered fern Adiantum capillus-veneris in the foothills of the Julian Alps, in Karst and in Istria. Based on a ...comparison with similar communities elsewhere in the southern Alps (northern Italy) we classified most of the recorded stands into the syntaxa Eucladio-Adiantetum eucladietosum and -cratoneuretosum commutati. Releves from the southern Julian Alps, located in comparatively slightly colder and moister local climate and the dolomite bedrock are classified into the new subassociation -hymenostylietosum recurvirostri subass. nova. Stands with the abundant occurrence of the liverwort Conocephalum conicum, are classified in to the new subassociation -conocephaletosum conici subass. nova. Stands in conglomerate rock shelters along the Soča at Solkan are classified into the new association Phyteumato columnae-Adiantetum ass. nova, a community of transitional character between the classes Adiantetea capilli-veneris and Asplenietea trichomanis.
Fitocenološko smo raziskali združbe, v katerih v prigorju Julijskih Alp, na Krasu in v Istri uspeva redka in ogrožena praprot Adiantum capillus-veneris. Na podlagi primerjav s podobnimi združbami drugod v južnih Alpah (severna Italija) smo večino popisanih sestojev uvrstili v sintaksona Eucladio-Adiantetum eucladietosum in -cratoneuretosum commutati. Popise iz južnih Julijskih Alp, ki smo jih naredili v nekoliko hladnejšem in bolj vlažnem krajevnem podnebju in na dolomitni podlagi uvrščamo v novo subasociacijo -hymenostylietosum recurvirostri subass. nova. Sestoje, kjer je obilno uspeval jetrenjak Conocephalum conicum, smo uvrstili v novo subasociacijo -conocephaletosum conici subass. nova. Sestoje v konglomeratnih spodmolih ob Soči pri Solkanu uvrščamo v novo asociacijo Phyteumato columnae-Adiantetum ass. nova, saj kažejo na stik združb dveh razredov Adiantetea capilli-veneris in Asplenietea trichomanis.
Deciphering deformation mechanisms within Quaternary sediments in a highly dynamic environment such as the southeast European Alps is often a challenging task that requires the use of a variety of ...methods. Due to the geohazards involved, the interpretation of deformation mechanisms can have a major impact on society and may enable the preparation of appropriate engineering solutions. We present an example of how deformation structures can be studied by integrating geomorphological, sedimentological and structural geological mapping using photogrammetric and leveling surveys, paleoseismological techniques, optically stimulated luminescence dating and ground penetrating radar surveys. Quaternary deposits on the slopes of the formerly glaciated Soča Valley near Most na Soči are tilted and dissected along numerous faults within the deformation zone of the Idrija Fault, a large, active, dextral strike-slip fault. Reconstruction of deformation history indicates that at least five deformation events occurred during deposition of the glaciofluvial succession interbedded with glaciolacustrine deposits, dated to Penultimate Glaciation. Ground penetrating radar profiles and outcrop observations reveal NE – SW striking faults, which are approximately perpendicular to the primary Idrija Fault. Based on the local geologic setting, we considered glaciotectonics, gravitational faulting due to ice-decay collapse or slope instability, and tectonic faulting as possible deformation mechanisms. Based on detailed documentation and analysis of the geometry and kinematics of the deformations, we interpret the observed deformations as secondary structures that result from paleoseismic activity of the Idrija Fault, and some structures resulting from glaciotectonics and gravitational faulting. The transtensional type of deformations at the studied site shows the local character of the main fault, which occurs here due to geometrical and kinematical changes of the Idrija Fault causing local transtension in the Most na Soči area. The complexity of the fault and the first paleoseismic evidence dating back to Penultimate Glaciation provide valuable new data for understanding the seismic hazard in the region.
•Origin of deformations within Quaternary sediments in a highly dynamic environment unraveled.•Glaciofluvial and glaciolacustrine deposits record recurrent faulting and non-tectonic deformations.•First paleoseismological evidence on the major Idrija Fault extending back to Penultimate Glaciation.•Local scale fault complexities reflect fault geometric and kinematic changes.
Located at the northeastern corner of the Adria microplate, the Alps‐Dinarides junction represents a key region for understanding how the Adria microplate interacts with stable Europe. However, ...little is known on how the present‐day deformation imposed by the rotation of the Adria microplate is absorbed across the Dinarides. Using morphotectonic analysis based on satellite and aerial images, accurate topographical maps, and digital elevation models combined with field investigations, we mapped in detail the three main active faults of the Northern Dinarides. Geomorphic and geological cumulative displacements ranging from a few meters to several kilometers have been identified on those faults and dated for the most recent ones using 36Cl exposure dating. Those results yielded a total right‐lateral motion of 3.8 ± 0.7 mm/yr oriented N317. Comparing our results with the motion expected from Adria rotation models suggests that the Northern Dinarides absorbs most of the predicted Adria‐Eurasia motion, thus representing the eastern boundary of the microplate. However, a significant E‐W component is lacking, suggesting that part of the stress imposed by the microplate rotation is transferred farther to the east. Finally, bounds placed on the Plio‐Pleistocene kinematics confirm that faulting onset occurred during the Early Pliocene and evidence a significant kinematic change at the Early/Middle Pleistocene boundary.
Key Points
Pleistocene slip rates of the Dinaric faults are derived from displaced markers and 36Cl CRE ages
Chronological bounds are placed on the kinematic evolution of the Dinarides over the Plio‐Pleistocene
Deformation in the Dinarides absorbs most of the Adria microplate rotation (versus stable Eurasia)
We present a paleoenvironmental reconstruction for the mountain fringe between the South-Eastern Alps and the Northern Dinarides (NE-Italy/W-Slovenia) during the Last Glacial Maximum. We focused on a ...new sedimentary and paleoecological archive spanning the LGM acme, located in an aggrading, permanently flooded and ponded plain, dammed by an active fluvioglacial megafan. The ecosystem reconstruction, based on two high resolution pollen records, is supported by a rich plant macrofossil flora and constrained by a robust radiocarbon chronology between 26 and 22calka BP. We show evidence for persistence of boreal trees and of different open boreal forest types throughout the LGM at the south-eastern mountain fringe of the Alps and the Northern Dinarides. Fire frequency is responsible for high, oscillating forest openness. The paleobotanical record is discussed in the light of the ecogeographic diversity of the region. A belt formed by Swiss stone pine, larch and dwarf mountain pine on limestone bedrock, and accompanied by Spruce in the floodplain, extended uphill, while proximal outwash plain supported Scots pine and dwarf mountain pine. These differences arise from groundwater regimes rather than from local climate variability. A steep moisture gradient from the semiarid pedoclimatic regime prevailing in the Adriatic alluvial plain to the forested mountain fringe is related to the orographic rainout triggered by southern air circulation. Mesophytic broad-leaved forest trees did not withstand the LGM temperature extremes in zonal ecosystems at the Alpine–Dinaric fringe; however, the fossil evidence suggests a number of microrefugia in karstic and thermal spring habitats of the northern Adriatic.
•Paleoenvironmental reconstruction at Alps–Dinarides fringe during the Last Glacial Maximum•Relationships between regional geological frame, sedimentary environments, and forest history•Persistence of trees and of different types of open boreal forest throughout the LGM
The effects of local geology on ground-motion amplification and building damage were studied in the Upper Soča valley (western Slovenia), which was struck by an earthquake (
M
LV=5.6) on 12 April ...1998 with an epicentre in the Krn mountains. Nakamura's method of microtremor analysis and one-dimensional modelling based on geophysical data (seismic refraction method, seismic velocity measurements in boreholes and DC electrical sounding) were applied in this study. Both methods showed significantly higher amplification in the frequency range of building vulnerability (2–10 Hz) in the Mala vas area of Bovec than in the central part of the town. This finding is consistent with the distribution of the earthquake damage in the area. In Koritnica, large differences in amplification were observed between the eastern rim of the village, built on carbonate bedrock and its central part lying on glacial deposits. In Čezsoča, where the thickness of fluvial deposits is about 20 m, amplifications between 2 and 3 in the frequency range of 2–10 Hz were obtained. In Plužna, which is located on flysch rocks covered with a thin layer of soil, the amplification in the same frequency range was low. In Sp. Drežniške Ravne, one of the most damaged villages during this earthquake, the amplification function has two distinctive peaks at 2 and 10.5 Hz. In Drežnica, however, where only slight damage was reported, the amplification level in the frequency range 2–10 Hz is low. The findings of this study indicate that large differences in damage to the buildings in the Upper Soča valley could be attributed to variations in the thickness and physical properties of Quaternary deposits, which appear to be rather heterogeneous.
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