31. Timeline of autumn phenology in temperate deciduous treesInge Dox, Jožica Gričar, Lorène Julia Marchand, Sebastien Leys, Paolo Zuccarini, Charly Geron, Peter Prislan, Bertold Mariën, Patrick Fonti, Holger Lange, Josep Peñuelas, Jan Van den Bulcke, Matteo Campioli, 2020, izvirni znanstveni članek Povzetek: Cessation of xylem formation or wood growth (CWG) and onset of foliar senescence (OFS) are key autumn phenological events in temperate deciduous trees. Their timing is fundamental for development and survival of trees, ecosystem nutrient cycling, the seasonal exchange of matter and energy between the biosphere and atmosphere and affect the impact and feedback of forests to global change. A large-scale experimental effort and improved observational methods have allowed us to compare the timing of CWG and OFS for different deciduous tree species in Western Europe, in particularly silver birch, a pioneer species, and European beech, a late-succession species, at stands of different latitudes, of different levels of site fertility, and for two years with contrasting meteorological and drought conditions i.e., the low-moderately dry 2017 and the extremely dry 2018. Specifically, we tested whether foliar senescence started before, after or concurrently with CWG. OFS and CWG occurred generally between late September and early November, with larger differences across species and sites for OFS. Foliar senescence started concurrently with CWG in most cases, except for the drier 2018 and, for beech, at the coldest site, where OFS occurred significantly later than CWG. Behavior of beech in Spain, the southern edge of its European distribution, was unclear, with no CWG, but very low wood growth at the time of OFS. Our study suggests that OFS is generally triggered by the same drivers of CWG or when wood growth decreases in late summer, indicating an overarching mechanism of sink limitation as a possible regulator of the timing of foliar senescence. Ključne besede: autumn phenology, xylem formation, foliar senescence, cambium, chlorophyll, radial growth, wood, decidiuous trees, common aspen, common beech, pedunculate oak, silver birch Objavljeno v DiRROS: 10.06.2020; Ogledov: 2130; Prenosov: 1347
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32. Inter-individual variability in spring phenology of temperate deciduous trees depends on species, tree size and previous year autumn phenologyLorène Julia Marchand, Inge Dox, Jožica Gričar, Peter Prislan, Sebastien Leys, Jan Van den Bulcke, Patrick Fonti, Holger Lange, Erik Matthysen, Josep Peñuelas, Paolo Zuccarini, Matteo Campioli, 2020, izvirni znanstveni članek Povzetek: We explored the inter-individual variability in bud-burst and its potential drivers, in homogeneous mature stands of temperate deciduous trees. Phenological observations of leaves and wood formation were performed weekly from summer 2017 to summer 2018 for pedunculate oak, European beech and silver birch in Belgium. The variability of bud-burst was correlated to previous' year autumn phenology (i.e. the onset of leaf senescence and the cessation of wood formation) and tree size but with important differences among species. In fact, variability of bud-burst was primarily related to onset of leaf senescence, cessation of wood formation and tree height for oak, beech and birch, respectively. The inter-individual variability of onset of leaf senescence was not related to the tree characteristics considered and was much larger than the inter-individual variability in bud-burst. Multispecies multivariate models could explain up to 66% of the bud-burst variability. These findings represent an important advance in our fundamental understanding and modelling of phenology and tree functioning of deciduous tree species. Ključne besede: leaf unfolding, wood formation, coloration, Pedunculate oak, European beech, Silver birch Objavljeno v DiRROS: 10.06.2020; Ogledov: 2059; Prenosov: 1220
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33. Growing stock of nectar- and honeydew-producing tree species determines the beekeepers' profitJanez Prešern, Jan Mihelič, Milan Kobal, 2019, izvirni znanstveni članek Ključne besede: beekeeping, forage, environment carrying capacity, non-wood forest products, nectar, honeydew flow Objavljeno v DiRROS: 29.04.2020; Ogledov: 2448; Prenosov: 688
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34. Patterns of tree microhabitats across a gradient of managed to old-growth conditions : a case study from beech dominated forests of South-Eastern SloveniaKristina Sever, Thomas Andrew Nagel, 2019, izvirni znanstveni članek Povzetek: An inventory of tree microhabitats was done in two unmanaged forests (Kobile and Ravna gora forest reserves) and one managed beech forest in SE Slovenia. The purpose of this study was to determine the influence of forest management, natural disturbances, and tree characteristics on microhabitat patterns. Forest structure and microhabitats were recorded in systematically placed plots (500 m2 in size) across each area. In total, we inventoried 849 trees on 54 plots and 1833 tree microhabitats. The results showed that forest management had no significant influence on the abundance of microhabitats per tree, but there were differences regarding microhabitat type between managed and unmanaged sites. There were substantially more microhabitats related to standing dead and live habitat trees in unmanaged forest (e.g. woodpecker cavities, insect galleries and bore holes, branch holes, dead branches and fruiting bodies of fungi), whereas in managed forests there were more tree microhabitats related to management (e.g. exposed heartwood, coarse bark, and epiphytic plants). The results also indicate that disturbance, tree diameter, vitality, and species influence the density, diversity, and occurrence of tree microhabitats. Ključne besede: forest management, biodiversity, tree microhabitats, beech forests, old-growth, veteran tree, natural disturbance, dead wood Objavljeno v DiRROS: 08.07.2019; Ogledov: 7283; Prenosov: 3118
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36. 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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37. Assessing maximum loads when skidding wood uphill with tractorsBoštjan Košir, Jurij Marenče, 2008, izvirni znanstveni članek Povzetek: The results of measuring maximum loads on different slopes when skidding uphill with WOO DY 110 cable skidder and adapted 4WD agricultural tractor AGT 835 are described in the article. Both tractors are very different and were chosen for the purpose of finding the limits of uphill skidding. Besides the slope, the pre-designated loads of different sizes and log orientation (butt-end or top-end forward) have been main variables. The trial was conducted on two concave shaped test skid trails in the forest. On the lower altitudes, the skid trails had small inclination, which slowly increased to 42% on the track where WOODY 110 was tested, and 27% where AGT 835 was measured. First the loads were skidded uphill with butt-end and then with top-end forward. The purpose was to choose too heavy loads, as we wished to stop tractors due to overload, but on different slopes. The proper load formation (butt-end forward if possible) in uphill skidding is most important on steeper skid trails. The dependency between maximum load and slope is linear. The calculated theoretical maximum load on horizontal surface enables us to make similar assessment for any other tractor weighing between 2 and 7 tons. For this purpose, John Deere 6220 and LIMB 80 LUXS adapted agricultural tractors for forest use were chosen and compared. The ratio between the tractor load on different slopes and tractor weight was calculated for all four tractors included in our comparison. Apart from the weight, tractor's engine torque (power) has the decisive influence on the load size. Maximum loads on different slope categories were calculated according to different engine powers. Ključne besede: tractor, skidding wood, maximum slope, maximum load Objavljeno v DiRROS: 12.07.2017; Ogledov: 4572; Prenosov: 1887
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38. Internal and external moisture transport resistance during non-stationary adsorption of moisture into woodBojan Bučar, 2007, izvirni znanstveni članek Povzetek: The assumption that non-stationary sorption processes associated with wood canbe evaluated by analysis of their transient system response to the disturbance developed is undoubtedly correct. In general it is, in fact, possible to obtain by time analysis of the transient phenomenon - involving the transition into an arbitrary new state of equilibrium - all data required for a credible evaluation of the observed system. Evaluation of moisture movement during drying or moistening requires determination of external moisture transfer resistance from or to wood surfaces, as well as internal resistance. Time-dependent changes in the moisture content of the spruce (Picea abies Karst.) samples of different thickness were monitored gravimetrically, during which the frequency of weighing was in accord with thespeed of moistening. It was assumed that quasi-isothermal sorption processes associated with wood could be evaluated as first order systems. The characteristic time constant ? determines, wholly and uniformly, the time dependence of the sorption process for the relevant sorption range of wood tissue. The connection between the time constant and the thickness of the sample measured in the direction of the material flux is potential, with the power depending solely on the relationship between the external mass transfer convection and internal diffusion resistance. To determine the said resistances or coefficients of mass transfer convection and diffusivity, the experiment must be carried out on samples of varying thickness. It is only in this way that the external mass transfer convection and internal diffusion resistance can be correctly distinguished. Ključne besede: wood sorption, first order system, time constant, mass transfer, diffusivity Objavljeno v DiRROS: 12.07.2017; Ogledov: 4687; Prenosov: 1952
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39. Inclusion of consumers in the forming of wood fuel trade market on the pattern of questionnaired householdsBenjamin Leskovec, Iztok Winkler, 2007, izvirni znanstveni članek Povzetek: The research of wood fuel trade is market management oriented at household level. We devoted our attention to determine the key questions, market segmentation and market potentials. 909 households, which took part in the questionnaire and received financial support to purchase a wood biomass boilerfrom 2003 until 2006, represented our data source. The analysed pattern of questionnaired households indicates a vast unrealized developmental potential at placing additional quantities of chunkwood and forest chips on the market. Own forests still represent the most important heating source in households. Switching to wood biomass heating is practiced particularly by fuel oil consumers. Since the consumer has been placed into the centre of our research, we present some fundamental findings on product making and product development, its price, sale, promotion and management control. Our findings indicate that right business decisions and the ability to adjust to the marketfluctuation enable us good developmental possibilities. Ključne besede: wood biomass, wood fuel trade, households, market management, chunkwood, forest chips, pellets, Slovenia Objavljeno v DiRROS: 12.07.2017; Ogledov: 4583; Prenosov: 2020
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40. Organisational model of a globally oriented wood industry companyJože Kropivšek, Rudi Rozman, 2007, pregledni znanstveni članek Povzetek: The paper provides an answer to the question as to in what way and with which organizational steps a wood industry company can be (more) adaptable and successful in a rapidly changing (global) business environment. The purpose ofthe article is to form an organizational model of a globally oriented wood industry company, considering the three required model properties: repeatability, efficiency and productiveness, as well as practical applicability. Research is limited to actual state in Slovenian wood industry practice with some specifics that should be considered by other implications of the research. Practical applicability of the model is based on these findings and is ensured by making guidelines on the basis of which companies can organise their businesses. These guidelines include suggested measures forindividual areas of business organization with the intention of increasing adaptability and innovativeness of business operation, improving competitive ability, and the ability of constant improvement. The paper provides a new organizational approach, specialized for making wood industry companies successful in the changing business environment. Ključne besede: adaptability, globalisation, model, organization, wood industry company Objavljeno v DiRROS: 12.07.2017; Ogledov: 4512; Prenosov: 1989
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