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Lipophilic Extractives in Heartwood of European Larch (Larix decidua Mill.)
No full textThe heartwood of two European larch trees was examined for the content of lipophilic extractives. Hexane was used as a solvent for extractions, while gas chromatography with fl ame ionisation detection and gas chromatography coupled to mass spectrometry were applied for analyses. Different lipophilic groups of compounds, such as fatty acids, resin acids, diterpenoids, sterols, steryl esters and triglycerides were identifi ed and quantitatively evaluated as well as individual low molecular mass components. Distribution of heartwood lipophilics in relation to the trunk heights was also determined and their most likely biological function in wood tissues discussed. The content of hexane extract increased with stem height. Various fatty and resin acids as well as diterpenoid alcohols and sterols were characterized. The predominating lipophilic compounds identifi ed were isopimaric acid and diterpenoid alcohol larixyl acetate. Their average concentrations in examined samples was between 2.0 and 2.5 mg/g. Higher molecular mass lipophilics, e.g. steryl esters and triglycerides, were also present with concentrations between 0.5 and 2.2 mg/g
Plasticity in variation of xylem and phloem cell characteristics of Norway spruce under different local conditions
No full textThere is limited information on intra-annual plasticity of secondary tissues of tree species growing under different environmental conditions. To increase the knowledge about the plasticity of secondary growth, which allows trees to adapt to specific local climatic regimes, we examined climate–radial growth relationships of Norway spruce [Picea abies (L.) H. Karst.] from three contrasting locations in the temperate climatic zone by analyzing tree-ring widths for the period 1932–2010, and cell characteristics in xylem and phloem increments formed in the years 2009–2011. Variation in the structure of xylem and phloem increments clearly shows that plasticity in seasonal dynamics of cambial cell production and cell differentiation exists on xylem and phloem sides. Anatomical characteristics of xylem and phloem cells are predominantly site-specific characteristics, because they varied among sites but were fairly uniform among years in trees from the same site. Xylem and phloem tissues formed in the first part of the growing season seemed to be more stable in structure, indicating their priority over latewood and late phloem for tree performance. Long-term climate and radial growth analyses revealed that growth was in general less dependent on precipitation than on temperature; however, growth sensitivity to local conditions differed among the sites. Only partial dependence of radial growth of spruce on climatic factors on the selected sites confirms its strategy to adapt the structure of wood and phloem increments to function optimally in local conditions
Smernice za sonaravno vzgajanje in trajnostno gojenje avtohtonih hitrorastočih drevesnih vrst na projektnem območju kot obnovljivega vira za proizvodnjo energije
No full textPogled na žled: delavnica o Gozdnogospodarskih in gozdnogojitvenih ukrepih po ujmah večjih razsežnosti zbornik povzetkov
Full text linkEUFORIA : European forest research and innovation area : programme and book of abstracts
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Četrto vmesno poročilo projekta ID:WOOD SEE/D/0227/1.2/X: perioda 1. 10. 2012 - 31. 12. 2014: clustering knowledge, innovation and design in the SEE WOOD sector
Full text linkComparison of selected landscape ecological forest metrics in two different landscape types
No full textBy analysing changes in landscape structure we can trace the influence they have on the evaluation of the diversity function of a forest. In the presented research, it was assessed which indices for computing areas, cores and aggregation tendencies that can be calculated with the Fragstats 4.2 programme best meet our needs, what limits they have and what we should pay special attention to. We considered differences in the resolution of incoming data and different rules for the calculation of raster cells. Both were compared for forests in two different landscape types: Kočevje and Slovenska Istra. The basic surface indices CA and PLAND proved to be the most suitable, while for more demanding purposes, AREA_AM can be used as well. For the evaluation of core areas, basic indices proved to be the most suitable, too, specifically TCA and CPLAND. Other important indices were the index of the number of core areas per surface unit DCAD and indices CORE_AM and DCORE_AM for a more detailed spatial evaluation of core areas, whereas most useful for the evaluation of aggregation tendency proved to be the patch density index PD
