11. New data on lower Permian rugose corals from the Southern Karavanke Mountains (Slovenia)Olga L. Kossovaya, Matevž Novak, Dieter Weyer, izvirni znanstveni članek Povzetek: Studies of upper Palaeozoic corals from the Southern Alps (Karavanke Mountains in Slovenia and Carnic Alps along the Austrian/Italian border) started at the end of the 19th century. Since the mid-20th century, corals of the Karavanke Mountains have been studied in detail by several authors. Recently, several coral type localities and the coral groups occurring therein have been einvestigated. This paper deals in particular with the study of Carinthiaphyllum Heritsch, 1936 and all previously known data have been revised within this study. Most specimens of Carinthiaphyllum originate from museum collections and from new findings in the Dovžanova Soteska area of northern Slovenia. Additional material is represented by newly found samples from the locality of Mt. Boč in eastern Slovenia. The stratigraphic position and age of the Carinthiaphyllum occurrences are determined by fusulinid and conodont assemblages. Two species, Carinthiaphyllum crasseseptatum Gräf & Ramovš, 1965 and C. ramovsi n. sp., are described herein. New morphological features, including root-like protrusions and connecting stereoplasmic tubes, have been found for the first time in gregaria growth mode. Therefore, these new observations provide evidence of a solitary gregaria growth mode: individuals are invariably separated with contact and reciprocal support only by root-like, sometimes channeled tubes occurring as outgrowths of the archaeothecal wall. An emended diagnosis of Carinthiaphyllum is proposed herein. The studied collection is housed in the Museum für Naturkunde (Leibniz-Institut) at the Humboldt University in Berlin.
Ključne besede: Gregaria corals, Carinthiaphyllum, Asselian-Sakmarian, Southern Alps
Objavljeno v DiRROS: 04.03.2022; Ogledov: 621; Prenosov: 227
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12. Assessing the protective role of alpine forests against rockfall at regional scaleChristian Scheidl, Micha Heiser, Sonja Vospernik, Elisabeth Lauss, Frank Perzl, Andreas Kofler, Karl Kleemayr, Francesco Bettella, Emanuele Lingua, Matteo Garbarino, Mitja Skudnik, Daniel Trappmann, Frédéric Berger, 2020, izvirni znanstveni članek Povzetek: Worldwide, mountain forests represent a significant factor in reducing rockfall risk over long periods of time on large potential disposition areas. While the economic value of technical protection measures against rockfall can be clearly determined and their benefits indicated, there is no general consensus on the quantification of the protective effect of forests. Experience shows that wherever there is forest, the implementation of technical measures to reduce risk of rockfall might often be dispensable or cheaper, and large deforestations (e.g. after windthrows, forest fires, clear-cuts) often show an increased incidence of rockfall events. This study focussed on how the protective effect of a forest against rockfall can be quantified on an alpine transregional scale. We therefore estimated the runout length, in terms of the angle of reach, of 700 individual rockfall trajectories from 39 release areas from Austria, Germany, Italy and Slovenia. All recorded rockfall events passed through forests which were classified either as coppice forests or, according to the CORINE classification of land cover, as mixed, coniferous or broadleaved dominated high forest stands. For each individual rockfall trajectory, we measured the forest structural parameters stem number, basal area, top height, ratio of shrub to high forest and share of coniferous trees. To quantify the protective effect of forests on rockfall, a hazard reduction factor is introduced, defined as the ratio between an expected angle of reach without forest and the back-calculated forest-influenced angles of reach. The results show that forests significantly reduce the runout length of rockfall. The highest reduction was observed for mixed high forest stands, while the lowest hazard reduction was observed for high forest stands dominated either by coniferous or broadleaved tree species. This implies that as soon as one tree species dominates, the risk reduction factor becomes lower. Coppice forests showed the lowest variability in hazard reduction. Hazard reduction due to forests increases, on average, by 7% for an increase in the stem number by 100 stems per hectare. The proposed concept allows a global view of the effectiveness of protective forests against rockfall processes and thus enable to value forest ecosystem services for future transregional assessments on a European level. Based on our results, general cost%benefit considerations of nature-based solutions against rockfall, such as protective forests as well as first-order evaluations of rockfall hazard reduction effects of silvicultural measures within the different forest types, can be supported.
Ključne besede: protection forests, rockfall, European Alps, rockfall hazard
Objavljeno v DiRROS: 13.07.2020; Ogledov: 1608; Prenosov: 948
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