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Ključne besede: gozdovi, varstvo gozdov, informacijski sistem, komunikacija, podatkovna zbirka, znanje, zdravje gozda, internet, medmrežje, kontinuiran vir, statistična analiza, obisk spletnega portala
Objavljeno v DiRROS: 13.04.2022; Ogledov: 123; Prenosov: 108
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Povzetek: Environmental conditions affect tree-ring width (TRW), wood structure, and, consequently, wood density, which is one of the main wood quality indicators. Although studies on inter- and intra-annual variability in tree-ring features or density exist, studies demonstrating a clear link between wood structure on a cellular level and its effect on wood density on a macroscopic level are rare. Norway spruce with its simple coniferous structure and European beech, a diffuse-porous angiosperm species were selected to analyze these relationships. Increment cores were collected from both species at four sites in Slovenia. In total, 24 European beech and 17 Norway spruce trees were sampled. In addition, resistance drilling measurements were performed just a few centimeters above the increment core sampling. TRW and quantitative wood anatomy measurements were performed on the collected cores. Resistance drilling density values, tree-ring (TRW, earlywood width–EWW, transition-TWW, and latewood width–LWW) and wood-anatomical features (vessel/tracheid area and diameter, cell density, relative conductive area, and cell wall thickness) were then averaged for the first 7 cm of measurements. We observed significant relationships between tree-ring and wood-anatomical features in both spruce and beech. In spruce, the highest correlation values were found between TRW and LWW. In beech, the highest correlations were observed between TRW and cell density. There were no significant relationships between wood-anatomical features and resistance drilling density in beech. However, in spruce, a significant negative correlation was found between resistance drilling density and tangential tracheid diameter, and a positive correlation between resistance drilling density and both TWW + LWW and LWW. Our findings suggest that resistance drilling measurements can be used to evaluate differences in density within and between species, but they should be improved in resolution to be able to detect changes in wood anatomy.
Ključne besede: wood structure, Fagus sylvatica, Picea abies, quantitative wood anatomy, xylem anatomy, wood density, increment borer
Objavljeno v DiRROS: 08.04.2022; Ogledov: 119; Prenosov: 139
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Povzetek: Over the last decades the vitality and productivity of European ash trees in Slovenia has been seriously impacted by the onset of canker and dieback disease symptoms on young and old trees, primarily identified as ash dieback caused by Hymenoscyphus fraxineus. Given the limited information available about the aetiology of this emerging disease, a study was carried out to isolate, identify and characterize the fungal species involved in the observed ash symptoms. Field surveys were conducted in five forest sites where 50 symptomatic branch samples were collected. All samples were inspected and used for fungal isolation. Based on morphology, colony appearance and DNA sequence data of the internal transcribed spacer region (ITS), 125 fungal colonies belonging to five species were isolated and identified. Only a few symptomatic ash samples yielded colonies of H. fraxineus, whereas Botryosphaeriaceae species were isolated with a high frequency, with Diplodia fraxini as the dominant species. A pathogenicity test proved that all isolated species were pathogenic on European ash, causing bark lesions and wood discoloration. All Botryosphaeriaceae species isolated in this study are reported for the first time on European ash in Slovenia.
Ključne besede: emerging disease, invasive species, Botryosphaeriaceae, pathogenicity
Objavljeno v DiRROS: 01.03.2022; Ogledov: 182; Prenosov: 152
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Ključne besede: gozdarstvo, gozdovi, okrogli les, grobo obdelan les, Rusija, izvoz, mednarodni trg
Objavljeno v DiRROS: 22.02.2022; Ogledov: 296; Prenosov: 114
Celotno besedilo (225,29 KB)

Ključne besede: gozdarstvo, gozdovi, gozdni lesni sortimenti, odkupne cene, zasebni gozdovi, bukev, iglavci, okrogli les
Objavljeno v DiRROS: 22.02.2022; Ogledov: 267; Prenosov: 115
Celotno besedilo (369,31 KB)