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Ključne besede: gozdarstvo, gozdovi, gozdni lesni sortimenti, merjenje, razvrščanje, uporaba standardov
Objavljeno v DiRROS: 27.07.2023; Ogledov: 362; Prenosov: 119
Celotno besedilo (2,78 MB)

Povzetek: Non-native pests, climate change, and their interactions are likely to alter relationships between trees and tree-associated organisms with consequences for forest health. To understand and predict such changes, factors structuring tree-associated communities need to be determined. Here, we analysed the data consisting of records of insects and fungi collected from dormant twigs from 155 tree species at 51 botanical gardens or arboreta in 32 countries. Generalized dissimilarity models revealed similar relative importance of studied climatic, host-related and geographic factors on differences in tree-associated communities. Mean annual temperature, phylogenetic distance between hosts and geographic distance between locations were the major drivers of dissimilarities. The increasing importance of high temperatures on differences in studied communities indicate that climate change could affect tree-associated organisms directly and indirectly through host range shifts. Insect and fungal communities were more similar between closely related vs. distant hosts suggesting that host range shifts may facilitate the emergence of new pests. Moreover, dissimilarities among tree-associated communities increased with geographic distance indicating that human-mediated transport may serve as a pathway of the introductions of new pests. The results of this study highlight the need to limit the establishment of tree pests and increase the resilience of forest ecosystems to changes in climate.
Ključne besede: mycology, insects, fungus, community of organisms, influence of the host, influence of climate, influence of geography
Objavljeno v DiRROS: 19.07.2023; Ogledov: 368; Prenosov: 210
Celotno besedilo (2,72 MB)
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Povzetek: European forests are becoming increasingly threatened by climate change and more frequent droughts. The likely responses of species to climate change will vary, affecting their competitiveness, their existence, and consequently, forest management decisions and measures. We determined the influence of climate on the radial growth of European beech and silver fir along the Carpathians to find similarities between the two species and the main differences. Along the Carpathian Mountains, seven sites with mature fir–beech stands above 800 m above sea level were selected and analyzed. Our study confirmed different responses depending on species and location. A more pronounced response of tree growth to climate was observed on the eastern side of the Carpathians, while it was less expressed or even absent on the southern sites. Both beech and fir show better radial growth with higher precipitation in July and slower growth with higher average and maximum temperatures in June of the current year. Fir demonstrates a positive correlation between radial growth and temperature in winter, while beech demonstrates a negative correlation between radial growth and temperature in summer. In the 1951–1960 decade, the average tree ring widths in fir and beech were largest at the southern sites compared to the other sites, but since 2011, the southern sites have had the lowest increase while northern sites have had the largest. Both species respond differently to climate and are likely to follow different competitive paths in the future.
Ključne besede: climate change, dendrochronology, radial growth response, meteorological parameters
Objavljeno v DiRROS: 28.06.2023; Ogledov: 491; Prenosov: 318
Celotno besedilo (7,44 MB)
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Povzetek: We investigated several aspects of windthrow that are relevant to our understanding and management of forest ecosystems. As an example, we used an extreme event in December 2017, when the strongest storm in recent history occurred in the Slovenian Dinaric High Karst. We examined influential factors such as soil properties, wind speed, precipitation and ecological consequences for the affected forests. Soil properties were measured around standing and fallen silver fir trees at all three research sites. Tree species composition in the regeneration was observed on plots with chemical and acoustic ungulate deterrents and on control plots without deterrents. Economic estimates of yield loss due to damage were calculated at the national level. A model of the potential threat from windthrow was also developed based on data collected from windthrow events and meteorological data over the past 20 years. Our results indicate that soil depth and mineral fraction depth were similar at sites with and without damaged trees and were not the determining factors for tree toppling. Plots with acoustic deterrents showed the most effective regeneration development, the least decline in silver fir and the greatest increase in noble hardwood seedlings, while plots with chemical deterrents showed the least browsing damage. The estimated economic loss of €16.1 million is 6.6% less than the harvest under normal conditions. The economic loss was relatively low due to the nature of the storm, with the predominant type of damage being uprooted trees with no damaged trunks. The windthrow hazard model revealed that a large number of consecutive events with strong winds in each section weakened the stand, which was subsequently knocked down during the next extreme wind and rainfall event.
Ključne besede: natural forest regeneration, windthrow, economic loss, browsing, ungulate deterrents, forest soil properties, potential threat model
Objavljeno v DiRROS: 27.06.2023; Ogledov: 1176; Prenosov: 546
Celotno besedilo (2,26 MB)
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Povzetek: Riparian forests are particularly vulnerable to environmental change and anthropogenic influences because they are highly dynamic ecosystems, thus proper adaptation measures are crucial. The implementation of these measures, however, strongly depends on the actors’ perceptions of the specific problems occurring in such forests. For understanding the constraints of specific interest groups toward different adaptation activities, information in this field is essential. By conducting a questionnaire survey we explore how different types of forest managers, i.e., forestry professionals, forest owners, and conservation managers, perceive the effects of environmental change on forest management in the recently established Transboundary Biosphere Reserve Mura-Drava-Danube. We show that these forest managers are highly aware of ongoing environmental changes and appraise deteriorating forest conditions, especially after observing changes themselves. Abiotic damage is expected to increase the most, followed by biotic damage, the spread of non-native species, and tree dieback. Nearly 80% of the survey respondents expect further changes and almost all of them intend to adapt their management of forests to mitigate or prepare for these changes. Nevertheless, we show differences in sensitivity to change and willingness to initiate adaptation actions by assessing adaptation thresholds: conservation managers appear generally more tolerant to changes, which results in higher thresholds to initiate management adaptation than forestry professionals
Ključne besede: biosphere reserve Mura-Drava-Danube, forest management, sensitivity to environmental change, stakeholder perception, adaptation thresholds, riparian forest tree species
Objavljeno v DiRROS: 31.05.2023; Ogledov: 373; Prenosov: 288
Celotno besedilo (2,00 MB)
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