21. Questionnaire on poplars and other fast-growing trees sustaining people and the environment 2016 - 2019 : report of the National Poplar CommissionGregor Božič, Andreja Ferreira, Anže Martin Pintar, 2020, elaborat, predštudija, študija Ključne besede: Poplar, Willow, Black Walnut, Black Locust, international commission, FAO, national report, questionnaire, genetics, forest protection, legislation, categorisation, forest products, ecology, Slovenia Objavljeno v DiRROS: 11.12.2020; Ogledov: 1502; Prenosov: 481
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22. 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: 1785; Prenosov: 1055
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23. The influence of abiotic and biotic disturbances on the protective effect of alpine forests against avalanches and rockfallsDomen Oven, Barbara Žabota, Milan Kobal, 2020, pregledni znanstveni članek Povzetek: Abiotic and biotic disturbances in alpine forests can reduce forest cover or change the structure of the forest and consequently reduce the protective effect of forest against natural hazards such as avalanches and rockfalls. In this review article, the effect of the main abiotic (forest fire, windthrow, ice break, snow break, avalanche and rockfall) and biotic (insects and pathogens) disturbances in protection forests are presented along with their potential influence on the protective effect of forest against avalanches and rockfalls. In general, natural disturbances negatively affect the protective effect of forest, especially in the case of large-scale and severe events, which in alpine areas are mostly caused by storms, bark beetle outbreaks, avalanches and forest fires. Climate change induced interactions between disturbances are expected to present challenges in the management of protection forests in the future. Ključne besede: natural disturbances, natural hazards, abiotic disturbances, biotic disturbances, protection forests, protective effect, stand parameters, rockfall, avalanche Objavljeno v DiRROS: 01.04.2020; Ogledov: 4513; Prenosov: 3369
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24. Effect of temperature on the eradication of house longhorn beetle larvae in wood by microwave treatmentMartin Klinc, Franc Pohleven, 2017, izvirni znanstveni članek Povzetek: In repressive protection of cultural/historical woodwork, microwaves have many advantages over conventional heating. The research%s objective was to examine conditions for eradication of house longhorn beetle larvae (Hylotrupes bajulus) in spruce wood (Picea abies) using microwaves. Larvae, inserted at different depths of spruce blocks containing 12% and 42% of moisture, were exposed to microwaves. Two apparatuses were used; a 750W commercial microwave chamber and a newly developed horn antenna microwave device with the power of 800W and a frequency of 2.45GHz, for targeted radiation. We discovered that the inner part of wood warmed up quicker than the surface heated to 65°C. For successful suppression larvae in the wood need to be heated to 54.5°C, for 10 seconds. The necessary exposure time increases with increasing thickness of wood. The surface of wood containing more moisture is heated quicker, but increased moisture slows down the penetration of microwaves into the wood specimen. Therefore, larvae in wood of lower moisture (12%) died faster, both those 20mm under surface (1.5min) and those at 130 mm of depth (10.5min). Ključne besede: wooden objects, repressive wood protection, microwaves, heating, wood moisture content, house longhorn beetle, Hylotrupes bajulus Objavljeno v DiRROS: 25.10.2017; Ogledov: 5256; Prenosov: 3030
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25. Influence of microwave heating in wood preservation on traditional surface coatingsMartin Klinc, Matjaž Pavlič, Marko Petrič, Franc Pohleven, 2017, izvirni znanstveni članek Povzetek: Microwaves are very effective at wood pest eradication. However, elevated temperatures may pose a risk of damaging surface coatings used on cultural and historical artefacts. Therefore, we monitored changes in patterns of the original paint taken from such objects along with newly prepared coatings. We evaluated visual, mechanical, and chemical modifications of coatings when exposed to microwaves (750W, 2.4GHz), at 60°C or 80°C for 10 min. Whether old or new, only water-based coatings have proven to be resistant to elevated temperatures and no damage was observed at 80°C. Blisters have formed on layers of new oil paints and natural resins due to insufficiently cured film. Temperatures above 80°C may cause melting of coniferous wood resin and thus transport of resin to the surface; on the other hand, temperatures up to 60°C are completely harmless. Mechanical and chemical changes of coatings exposed to microwaves were not observed, but the studies showed that colour and gloss exhibited minor changes. Ključne besede: wood, wood coatings, wood protection, microwaves, heating Objavljeno v DiRROS: 03.07.2017; Ogledov: 6121; Prenosov: 3486
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