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  • 1.
    Adamopoulos, Stergios
    et al.
    Georg-August-University Göttingen, Germany ; Technological Educational Institute of Larissa, Greece.
    Bastani, Alireza
    Georg-August-University Göttingen, Germany.
    Gascón-Garrido, Patricia
    Georg-August-University Göttingen, Germany.
    Militz, Holger
    Georg-August-University Göttingen, Germany.
    Mai, Carsten
    Georg-August-University Göttingen, Germany.
    Adhesive bonding of beech wood modified with a phenol formaldehyde compound2012Ingår i: European Journal of Wood and Wood Products, ISSN 0018-3768, E-ISSN 1436-736X, Vol. 70, nr 6, 897-901 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Untreated (controls) and phenol–formaldehyde (PF)-modified beech wood (10 and 25 % solid content) were glued with phenol resorcinol formaldehyde (PRF) and polyvinyl acetate (PVAc). Shear strength of PRF-bonded specimens was higher than that of PVAc-bonded ones under dry and wet conditions irrespective of the pre-treatment. Under dry conditions, only PVAc-bonded specimens exhibited reduction in shear strength due to PF-modification with 25 % PF concentration as compared to the controls. PF treated wood provided inferior bonding under wet conditions with the exception of 25 % PF concentration specimens glued with PRF adhesive. Modification with PF resulted in a decrease of adhesive penetration into the porous network of interconnected cells, especially at 25 % PF concentration.

  • 2.
    Bonarski, Jan T.
    et al.
    Polish Academy of Sciences.
    Olek, Wiesław
    Poznań University of Life Sciences.
    Pospiech, Jan
    Polish Academy of Sciences.
    Kifetew, Girma
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Application of spatial distribution of cellulose crystallites for determining wood anisotropy2012Ingår i: Workshop micro-characterisation of wood materials and properties: 24–26 October, 2012 Edinburgh, Scotland, UK, 2012, 29-30 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    The anisotropy of wood properties is related to the ultrastructural organization of wood cell walls. The mean microfibril angle (MFA) is the most obvious parameter quantifying the ultrastructure. Various methods for the MFA measurements have been developed. However, the direct microscopic techniques (both light and electron ones) as well as the indirect X-ray methods were dominating. However, the helical arrangement of cellulose fibrils in wood cells around the longitudinal anatomical direction results in spatial changes of orientations of the lattice planes. Such misorientation between the longitudinal anatomical direction and the microfibril axes has a spatial character and therefore, it can not be correctly described by a single parameter only, i.e. by MFA. The most comprehensive description of the spatial distribution of orientations of cellulose crystallites can be obtained when defining a set of parameters consisting of the rotating axis (given by the polar coordinates θ and ψ and referred to the sample framework) as well as the angle of rotation (ω) around the axis. In order to analyze of wood anisotropy a stereographic projection of the rotating axes on the base of the (010) plane of the lattice cell of cellulose is recommended. Regarding the crystallographic system of the monoclinic lattice of cellulose and the two-fold symmetry of the <010> axis, the projection plane corresponded to the a-c plane of the elementary cell [3]. An example of the projection and the distribution of the rotation axis characterizing the spatial organization of wood microfibrils is given in Fig. 1. The θ, ψ and ω parameters were determined with the original computer program SpaceWood. The parameters were determined regarding the crystallographic symmetry and the parameters of the unit-cell of cellulose given by Zugenmaier [3].

  • 3.
    Blomqvist, Lars
    et al.
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Rowell, Roger
    University of Wisconsin-Madison.
    Bio-based adhesives at laminated veneers2012Ingår i: Proceedings of the 8th meeting of the Northern European Network for Wood Science and Engineering (WSE) / [ed] Antanas Baltrušaitis and Kristina Ukvalbergiené, Kaunas, Lithuania, 2012, 221-225 s.Konferensbidrag (Refereegranskat)
  • 4.
    Bader, Thomas K.
    et al.
    Vienna University of Technology, Austria.
    Hofstetter, Karin
    Vienna University of Technology, Austria.
    Alfredsen, Gry
    Norwegian Forest and Landscape Institute, Norway.
    Bollmus, Susanne
    Georg-August-University of Göttingen, Germany.
    Changes in microstructure and stiffness of Scots pine (Pinus sylvestris L) sapwood degraded by Gloeophyllum trabeum and Trametes versicolor Part II: Anisotropic stiffness properties2012Ingår i: Holzforschung, ISSN 0018-3830, E-ISSN 1437-434X, Vol. 66, nr 2, 199-206 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Fungal decay considerably affects the macroscopic mechanical properties of wood as a result of modifications and degradations in its microscopic structure. While effects on mechanical properties related to the stem direction are fairly well understood, effects on radial and tangential directions (transverse properties) are less well investigated. In the present study, changes of longitudinal elastic moduli and stiffness data in all anatomical directions of Scots pine (Pinus sylvestris) sapwood which was degraded by Gloeophyllum trabeum (brown rot) and Trametes versicolor (white rot) for up to 28 weeks have been investigated. Transverse properties were found to be much more deteriorated than the longitudinal ones. This is because of the degradation of the polymer matrix between the cellulose microfibrils, which has a strong effect on transverse stiffness. Longitudinal stiffness, on the other hand, is mainly governed by cellulose microfibrils, which are more stable agains fungal decay. G. trabeum (more active in earlywood) strongly weakens radial stiffness, whereas T. versicolor (more active in latewood) strongly reduces tangential stiffness. The data in terms of radial and tangential stiffnesses, as well as the corresponding anisotropy ratios, seem to be suitable as durability indicators of wood and even allow conclusions to be made on the degradation mechanisms of fungi.

  • 5. Kielmann, BC
    et al.
    Militz, Holger
    Adamopoulos, Stergios
    Technological Educational Institute of Larissa, Greece.
    Combined N-Methylol melamine-colouring agent modification of hardwoods to improve their performance under use class 32012Ingår i: The Sixth European Conference on Wood Modification: Proceedings / [ed] Dennis Jones, Holger Militz, Marko Petrič, Franc Pohleven, Miha Humar, Matjaž Pavlič, University of Ljubljana , 2012, 437-446 s.Konferensbidrag (Refereegranskat)
  • 6. Poudel, Bishnu Chandra
    et al.
    Sathre, Roger
    Mid Sweden University, Sweden.
    Bergh, Johan
    Swedish University of Agricultural Sciences (SLU).
    Drössler, Lars
    Nordin, Annika
    Nilsson, Urban
    Lundmark, Tomas
    Comparison of biomass production and total carbon balance of continuous-cover and clear-cut forestry in Sweden2012Ingår i: IUFRO Conference, Division 5, Forest Products. 8 - 13 July. Estoril Congress Centre, Lisbon, Portugal, Estoril Conference Center, Lisbon, Portugal: IUFRO , 2012Konferensbidrag (Refereegranskat)
  • 7.
    Füssl, Josef
    et al.
    Vienna University of Technology, Austria.
    Bader, Thomas K.
    Vienna University of Technology, Austria.
    Eberhardsteiner, Josef
    Vienna University of Technology, Austria.
    Computational Mechanics for Advanced Timber Engineering: from material modeling to structural applications2012Ingår i: IACM Expressions, nr 32, 6-11 s.Artikel i tidskrift (Övrigt vetenskapligt)
  • 8.
    Malmqvist, Cecilia
    et al.
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Albrecht, Nina
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Course Reflection as an Improvment Tool with Special Reference to Equality in Forestry Education2012Ingår i: EDULEARN12: 4TH INTERNATIONAL CONFERENCE ON EDUCATION AND NEW LEARNING TECHNOLOGIES, 2012, 896-900 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    Since the start in 2001, approximately 3,000 students have attended courses in Sustainable Smallscale Forestry at the Linnaeus University in Sweden. The majority of students are private forest owners. The courses in Sustainable Small-scale Forestry have been successful in recruiting and educating both men and women, unlike many other Swedish forestry educations. The number of students correspond to the relation between female (38 %) and male (62 %) forest owners. Sociocultural perspectives on learning promotes the importance of social contexts and the idea of sharing thoughts and experiences with other people in order to motivate and confirm knowledge. Therefore cooperation and student focused learning with peer reviews and reflection is often a given element when planning a course. But how do educators work with their own internal course development? What kind of reflection and peer review can be helpful in improving your own course? At the Linnaeus University, a systematic course reflection was introduced to the teachers in the Forestry Department in 2009. The purpose was to help the teaching staff perceive shortcomings and possibilities of amelioration, as well as to systemize and make improvement efforts to courses more efficient. The process was a spin-off from the participation in the National Strategy for Equality within the Forestry Sector that was initiated by the Swedish government in 2009. The Strategy focused on three actions, where Education was one of them. Linnaeus University played an active part in the progress to create and realize the National Strategy for Equality that was introduced in April 2010. The aim of this study was to evaluate the prospect of course reflection to improve university courses and to pay attention to a specific issue. The benefit of course reflection in the improvement work was assessed by having members of the teaching staff reflect over their own use of course reflection (meta-reflection). The study includes twelve persons from the teaching staff, two from each of seven different courses in Sustainable Small-scale Forestry. The education is internet-based distance courses with a blended learning approach. The teachers took notes during and after the course and put the thoughts down in a standardized form. In addition to the general course related issues, they were asked to focus on how equality (between women and men, ethnical background, age etc) has been promoted in the course. The evaluation of the study is in progress. Preliminary results will be presented in the summer of 2012.

  • 9.
    Gloimüller, Stefan
    et al.
    Vienna University of Technology, Austria.
    de Borst, Karin
    Vienna University of Technology, Austria.
    Bader, Thomas K.
    Vienna University of Technology, Austria.
    Eberhardsteiner, Josef
    Vienna University of Technology, Austria.
    Determination of the linear elastic stiffness and hygroexpansion of softwood by a multilayered unit cell using poromechanics2012Ingår i: Interaction and Multiscale Mechanics, An International Journal, ISSN 1976-0426, Vol. 5, nr 3, 229-265 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Hygroexpansion of wood is a known and undesired characteristic in civil engineering. When wood is exposed to changing environmental humidity, it adsorbs or desorbs moisture and warps. The resulting distortions or - at restrained conditions - cracks are a major concern in timber engineering. We herein present a multiscale model for prediction of the macroscopic hygroexpansion behavior of individual pieces of softwood from their microstructure, demonstrated for spruce. By applying poromicromechanics, we establish a link between the swelling pressure, driving the hygroexpansion of wood at the nanoscale, and the resulting macroscopic dimensional changes. The model comprises six homogenization steps, which are performed by means of continuum micromechanics, the unit cell method and laminate theory, all formulated in a poromechanical framework. Model predictions for elastic properties of wood as functions of the moisture content closely approach corresponding experimental data. As for the hygroexpansion behavior, the swelling pressure has to be back-calculated from macroscopic hygroexpansion data. The good reproduction of the anisotropy of wood hygroexpansion, based on only a single scalar calibration parameter, underlines the suitability of the model. The multiscale model constitutes a valuable tool for studying the effect of microstructural features on the macroscopic behavior and for assessing the hygroexpansion behavior at smaller length scales, which are inaccessible to experiments. The model predictions deliver input parameters for the analysis of timber at the structural scale, therewith enabling to optimize the use of timber and to prevent moisture-induced damage or failure.

  • 10.
    Adamopoulos, Stergios
    et al.
    Technological Educational Institute of Larissa, Greece.
    Voulgaridis, Elias
    Aristotle University of Thessaloniki, Greece.
    Effect of hot-water extractives on water sorption and dimensional changes of black locust wood2012Ingår i: Wood research, ISSN 1336-4561, Vol. 57, nr 1, 69-78 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The hygroscopicity and the dimensional changes of black locust heartwood were investigated in relation to the progressive removal of hot-water extractives. Extraction in the original specimen form removed only part of the total 8.434 % hot-water extractives, 3.601 % in first extraction and 4.642 % in second extraction. As a result, the adsorption and desorption behaviour of black locust wood was little affected by the extraction and only a small increase was observed in dimensional changes at every RH from 0 % to 97 %. The mean hysteresis coefficient was also little affected by extraction and increased from 0.75 at the unextracted stage to 0.77 at the second extraction. The initial dimensional change 3.76 % of unextracted black locust wood corresponding to RH changes between 43 % and 80 % increased after the first and second extraction to the respective values of 3.96 % and 3.97 %. Extraction had no effect on the significant, very strong linear relationships between swelling or shrinkage and equilibrium moisture content (EMC).

  • 11. Olek, Wiesław
    et al.
    Kifetew, Girma
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Bonanski, Jan T.
    Marklund, Erik
    Effects of cell wall ultrastructure on the transverse anisotropy of wood shrinkage2012Ingår i: Experimental and Computational Micro-Characterization Techniques in Wood Mechanics –COST Action FP0802, 2012Konferensbidrag (Refereegranskat)
  • 12.
    Jensen, Anna M.
    et al.
    Swedish University of Agricultural Sciences.
    Löf, Magnus
    Swedish University of Agricultural Sciences.
    Witzell, Johanna
    Swedish University of Agricultural Sciences.
    Effects of competition and indirect facilitation by shrubs on Quercus robur saplings2012Ingår i: Plant Ecology, ISSN 1385-0237, E-ISSN 1573-5052, Vol. 213, nr 4, 535-543 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Indirect facilitation by shrubs has been suggested as a cost-effective way of regenerating oaks in forests of conservation interest. In this study, we tested whether shrubs can enhance growth in pedunculate oak (Quercus robur) by suppressing herbaceous competitors. We studied interactions between young oaks, shrubs, and/or herbaceous vegetation in an open-field experiment, in southern Sweden, over the first 3 years after planting. Oak saplings were grown in four competition treatments: no competing vegetation; with herbaceous vegetation; with shrubs; and with both herbaceous vegetation and shrubs. Competition from shrubs and herbaceous vegetation both reduced stem diameter and biomass accumulation, but they affected biomass partitioning differently. Saplings grown with competition from shrubs partitioned biomass primarily into height growth, while those saplings exposed to competition from herbaceous vegetation invested a relatively higher proportion in root growth. Competition between shrubs and herbaceous vegetation reduced the above-ground biomass of the herbaceous vegetation, resulting in an indirect facilitative effect for the oaks during the first 2 years after planting. However, during the third year, shrubs had a negative effect on biomass accumulation. In summary, results from this study suggest that shrubs indirectly facilitate biomass accumulation of oak saplings by suppressing herbaceous vegetation, possibly by reducing competition for below-ground resources. However, owing to the relatively short duration of positive net outcome for the oak, we recommend that a longer-term assessment of the interaction between oak regeneration and neighboring shrubs be made before the outcome of this study is applied to practical forestry.

  • 13.
    Bader, Thomas K.
    et al.
    Vienna University of Technology, Austria.
    Wikete, Christoph
    de Borst, Karin
    Elastic Properties of Hardwood at Different Length Scales Predicted by Means of a Micromechanical Model2012Ingår i: Proceedings of the 6th European Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2012), Vienna University of Technology, Vienna, Austria, Vienna, Austria, 2012Konferensbidrag (Övrigt vetenskapligt)
  • 14.
    Gellerich, Antje
    et al.
    Georg-August-University Göttingen, Germany.
    Röhl, Kay
    Georg-August-University Göttingen, Germany.
    Adamopoulos, Stergios
    Georg-August-University Göttingen, Germany.
    Militz, Holger
    Georg-August-University Göttingen, Germany.
    Evaluation of fungal infestation and decay in a simulated use class 3 situation (block test) after some years of exposure2012Ingår i: The 43rd Annual Meeting of IRG: Abstracts of documents, Stockholm, 2012Konferensbidrag (Refereegranskat)
    Abstract [en]

    The so named “block test” was designed as part of the assessment methodology for testing the behaviour of natural and modified wood used under use class 3 (EN 335-2) conditions. The test was developed to expose the wood close to the ground to an environment with high humidity and high biological activity, but not in soil contact. The present study describes the evaluation of fungal infestation and decay of untreated samples in different blocks depending on their exposure time, positioning within the block and wood species. After 4 years outside exposure samples showed visible signs of decay. The highest rate of decay was visible in the middle layers of the block. After 7 and 8 years outside exposure, samples of all layers were infested with a similar intensity of different types of decay. The results have shown that in the bottom layer close to ground the major type of decay is white rot as well as white rot in combination with soft rot. In contrast, samples from the middle layers and top layer were infested mainly by brown and white rot but also soft rot was observed. The test setup is according the definition of use classes a method for use class 3 applications because the samples are out of ground contact. But the infestation of samples in all layers by soft rot indicated that under use class 3 test conditions but with elevated moisture conditions soft rot attack can occur and should make part of a proper test design.

  • 15.
    Altgen, Michel
    et al.
    Georg-August-University, Germany.
    Adamopoulos, Stergios
    Georg-August-University, Germany.
    Ala-Viikari, Jukka
    International ThermoWood Association, Finland.
    Hukka, Antti
    International ThermoWood Association, Finland.
    Tetri, Timo
    Jartek Oy, Finland.
    Militz, Holger
    Georg-August-University, Germany.
    Factors Influencing the Crack Formation in Thermally Modified Wood2012Ingår i: The Sixth European Conference on Wood Modification: Proceedings / [ed] Dennis Jones, Holger Militz, Marko Petrič, Franc Pohleven, Miha Humar, Matjaz Pavlič, University of Ljubljana , 2012, 149-158 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    Wood anatomical changes during a thermal modification process are likely to adverselyaffect the properties of the final product. Therefore, an anatomical investigation was performed on Scots pine and Norway spruce material coming from different steps of the regular production of ThermoWood. A macroscopic evaluation using an evaluation scale between 1 and 3 revealed typical drying defects in some of the kiln dried boards. Nevertheless, at least 50 % of the unmodified boards were defect free (CR = 1), while at least 90 % of the thermally modified boards were not defect free (CR = 2 and CR = 3), thus indicating that surface cracks become more frequent and severe after the modification process. However there was no evidence of an impact of the conditioning stage on the crack formation. Even though most of the surface cracks were removed by planing, microscopic analysis by means of light and scanning electron microscopy revealed that there might still be micro-defects within the ThermoWood. Such micro-defects were mainly associated with parenchyma or epithelial cells of the rays or the resin canals. Furthermore, longitudinal cracks within the tracheids were observed within the earlywood latewood interface or within the earlywood. During repeated drying and wetting cycles, the crack formation was higher for thermally modified wood than for unmodified, despite a lower water uptake and a better dimensional stability. After the third cycle, the average crack rating of thermally modified wood was at least twice as high as for the unmodified wood. It was concluded that this increase in the crack formation might be caused by the presence of micro-defects that potentially act as a starting point for more severe cracks during swelling and shrinkage.

  • 16.
    Poudel, Bishnu Chandra
    Mid Sweden University.
    Forest Biomass Production Potential and its Implications for Carbon Balance2012Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    An integrated methodological approach is used to analyse the forestbiomass production potential in the Middle Norrland region of Sweden, and itsuse to reduce carbon emissions. Forest biomass production, forest management,biomass harvest, and forest product use are analyzed in a system perspectiveconsidering the entire resource flow chains. The system-wide carbon flows as wellas avoided carbon emissions are quantified for the activities of forest biomassproduction, harvest, use and substitution of non-biomass materials and fossil fuels.Five different forest management scenarios and two biomass use alternatives aredeveloped and used in the analysis. The analysis is divided into four main parts. Inthe first part, plant biomass production is estimated using principles of plantphysiologicalprocesses and soil-water dynamics. Biomass production is comparedunder different forest management scenarios, some of which include the expectedeffects of climate change based on IPCC B2 scenario. In the second part, forestharvest potentials are estimated based on plant biomass production data andSwedish national forest inventory data for different forest managementalternatives. In the third part, soil carbon stock changes are estimated for differentlitter input levels from standing biomass and forest residues left in the forestduring the harvest operations. The fourth and final part is the estimation of carbonemissions reduction due to the substitution of fossil fuels and carbon-intensivematerials by the use of forest biomass. Forest operational activities such asregeneration, pre-commercial thinning, commercial thinning, fertilisation, andharvesting are included in the analysis. The total carbon balance is calculated bysumming up the carbon stock changes in the standing biomass, carbon stockchanges in the forest soil, forest product carbon stock changes, and the substitutioneffects. Fossil carbon emissions from forest operational activities are calculated anddeducted to calculate the net total carbon balance.

    The results show that the climate change effect most likely will increaseforest biomass production over the next 100 years compared to a situation withunchanged climate. As an effect of increased biomass production, there is apossibility to increase the harvest of usable biomass. The annual forest biomassproduction and harvest can be further increased by the application of moreintensive forestry practices compared to practices currently in use. Deciduous treesare likely to increase their biomass production because of climate change effectswhereas spruce biomass is likely to increase because of implementation ofintensive forestry practices.

    Intensive forestry practices such as application of pre-commercialthinning, balanced fertilisation, and introduction of fast growing species to replaceslow growing pine stands can increase the standing biomass carbon stock. Soilcarbon stock increase is higher when only stem-wood biomass is used, comparedto whole-tree biomass use. The increase of carbon stocks in wood productsdepends largely on the magnitude of harvest and the use of the harvested biomass.The biomass substitution benefits are the largest contributor to the total carbonbalance, particularly for the intensive forest management scenario when wholetreebiomass is used and substitutes coal fuel and non-wood constructionmaterials. The results show that the climate change effect could provide up to 104Tg carbon emissions reduction, and intensive forestry practices may furtherprovide up to 132 Tg carbon emissions reduction during the next 100 years in thearea studied.

    This study shows that production forestry can be managed to balancebiomass growth and harvest in the long run, so that the forest will maintain itscapacity to increase standing biomass carbon and provide continuous harvests.Increasing standing biomass in Swedish managed forest may not be the mosteffective strategy to mitigate climate change. Storing wood products in buildingmaterials delays the carbon emissions into the atmosphere, and the wood materialin the buildings can be used as biofuel at the end of a building life-cycle tosubstitute fossil fuels.

    These findings show that the forest biomass production potential in thestudied area increases with climate change and with the application of intensiveforestry practices. Intensive forestry practice has the potential for continuousincreased biomass production which, if used to substitute fossil fuels andmaterials, could contribute significantly to net carbon emissions reductions andhelp mitigate climate change.

  • 17.
    Hameed, Mahmood
    Damascus University, Syria.
    Forestry and Forest Nersery (Text-book)2012 (uppl. 1)Bok (Övrigt vetenskapligt)
    Abstract [ar]

    الفهرس

     

    مقدمة.......................................................... .........................17

    الفصل الأول: علم الحراج Forestry.............................................19

    -علم الحراج (الغابات) و علاقته بالعلوم الأخرى..................................19

    -أنواع الغابات و المجموعات الشجرية.............................................23

    *الغابات الطبيعية....................................................................23

    *الغابات الصناعية..................................................................25

    -فوائد الغابات.......................................................................26

    -أنواع الغابات في العالم...........................................................31

    -مساحة الغابات والاستهلاك العالمي من الأخشاب.............................33

    -الموارد الشجرية في سورية و لبنان و فلسطين و الأردن.......................37

    -تقسيم المجاميع الشجرية والغابات: .............................................41

    *من حيث التركيبُ و الحالة.......................................................41

    *من حيث العمرُ...................................................................42

    *من حيث الإدارةُ والمعاملةُ........................................................42

    *من حيث التوزيع الجغرافي.........................................................42

    *من حيث الهدف....................................................................42

     

    الفصل الثاني: علم تصنيف الأشجار وتوزيعها الجغرافي Dendrology.....43

    -تعريف علم تصنيف الأشجار و توزيعها الجغرافي..............................43

    -موقع الأشجار في التقسيم النباتي................................................43

    *أنواع النباتات الخشبية............................................................43

    *التقسيم النباتي للأشجار و موقعها ضمن المملكة النباتية.....................44

    -المعايير المستخدمة في التعرف إلى الأنواع الخشبية.........................45

    -تصنيف معراة البذور (المخروطيات) Gymnosperm: الرتب ، أهم الفصائل ، أهم الأجناس ، أهم الأنواع........................................................45

    *رتبة الصنوبريات Pinales ، فصيلة الصنوبريات Pinaceae: جنس الصنوبر Pinus L. ، جنس الأرز Cedrus Link. ، جنس الشوح Abies L. ، جنس التنوب Picea A. Dictr.. .....................................................46

    *رتبة السرويات Cupressales ، فصيلة السرويات Cupressaceae: جنس السرو Cupressus L. ، جنس العرعر Juniperus L. ، جنس العفص Biota Endl. ، فصيلة Taxodiaceae: جنس السيكويا Sequoia L.. .............52

    -تصنيف مستورات البذور (عريضات الأوراق) Angiosperm: الرتب ، أهم الفصائل ، أهم الأجناس ، أهم الأنواع..............................................56

    *رتبة المغنوليات Magnoliales ، الفصيلة الغارية Lauraceae: حنس الغار Laurus L. .........................................................................57

    *رتبة Urticales ، فصيلة Ulmaceae: جنس الأولم Ulmus L. ، جنس الميس Celtis L. ، الفصيلة التوتية Moraceae: جنس التوت Morus L. ، جنس الماكلورة Maclura Nutt. ، جنس التين Ficus L.. ....................57

    *رتبة الجوزيات Juglandales ، فصيلة الجوزيات Juglandaceae: جنس الجوز Juglans L. ، جنس البيكان Carya Nutt.. ..........................60

    *رتبة الزانيات Fagales ، الفصيلة الزانية Fagaceae: جنس الكستناء Castanea Adans ، جنس السنديان Quercus L. ، جنس الزان Fagus L. ، الفصيلة البيتولية Betulaceae: جنس النغث Alnus L. ، جنس الشرد Carpinus L. ، جنس الصلع Ostrya ، جنس البندق Corylus .............61

    *رتبة Casuarinales ، فصيلة Casuarinaceae: جنس الكازورينا Casuarina Rumph. ............................................................67

    *رتبة Malvales ، فصيلة Sterculiaceae: جنس البرختيتون Brachychiton. ....................................................................68

    *رتبة Violales ، فصيلة Tamaricaceae: جنس الطرفاء (الإثل) Tamarix.............................................................................69

    *رتبة الصفصافيات Salicales ، الفصيلة الصفصافية Salicaceae: جنس الصفصاف Salix Tour. ، جنس الحور Populus L.. .......................70

    *رتبة العجرميات Ericales ، الفصيلة العجرمية Ericaceae: جنس العجرم Erica. ...............................................................................73

    *رتبة Ebenales ، فصيلة العبهر Styracaceae: جنس العبهر Styrax...74

    *رتبة الورديات Rosales ، فصيلة Platanaceae: جنس الدلب Platanus ، الفصيلة الوردية Rosaceae: جنس الإجاص Pirus L. ، جنس الغبيراء Sorbus L. ، جنس الزعرور Crataegus L. ، جنس الخوخ Prunus L. ، جنس اللوز Amygdalus  ، جنس البلان Porerium L.  ....................75

    *رتبة البقوليات Leguminales ، فصيلة Mimosaceae: جنس الطلح Acacia Willd. ، جنس الغاف Prosopis L. ، فصيلة Cesalpiniaceae: جنس الخرنوب Ceratonia L. ، جنس Gleditsia L. ، جنس خف الجمل Bauhinia L. ، جنس Poinciana L. ، جنس Parkinsonia L.. الفصيلة الفراشية Papilionaceae: جنس المسكة Robinia L. ، جنس Sophora L. ، جنس الوزال Spartium L. ، جنس الجربان Calyctome Link. ..........80

    *رتبة الآسيات Myrtales ، الفصيلة الآسية Myrtaceae: جنس الآس Myrtus L. ، جنس Eucalyptus. ..............................................87

    *رتبة Proteales ، الفصيلة الزيزفونية Elaeagnaceae: جنس الزيزفون Elaeagnus. .......................................................................89

    *رتبة Rhamnales ، فصيلة Rhamnaceae: جنس Rhamnus L. ، جنس Paluirus Juss. ، جنس Zizyphus Juss.. .................................90

    *رتبة Sapindales ، فصيلة Anacardiaceae: جنس البطم Pistacia L. ، جنس السماق Rhus L. ، جنس Schinus L. ، فصيلة Aceraceae: جنس القيقب Acer L. ، فصيلة Simaroubaceae: جنس لسان الطير Ailanthus ، فصيلة Meliaceae: جنس الإزدرخت Melia. ................................92

    * رتبة Gentianales ، فصيلة Apocynaceae : جنس Nerium و رتبة Lamiales ، فصيلة Verbenaceae: جنس Lippia L.. ....................97

    *رتبة Scrophulariales ، فصيلة Bignoniaceae: جنس Catalpa Guss. ، جنس Jacaranda Juss.. .....................................................98

    *رتبة Oleales ، الفصيلة الزيتونية Oleaceae: جنس الزيتون Olea L. ، جنس الدردار Fraxinus L. ، جنس الزرود Phillyrea L. ، جنس تمر حنا Ligustrum. ..................................................................99-102

     

    الفصل الثالث: بيئة الغابات Forest Ecology  .............................103

    -تعريف بيئة الغابات................................................................103

    - تأثير العوامل المناخية والأرضية والطبوغرافية والحيوية في النبت الحراجي..103

    - تأثير العوامل المناخية Climatic Factors...................................103

    -تأثير العوامل الأرضية Edaphic Factors....................................107

    - تأثير العوامل الطبوغرافية Topographical Factors .....................108

    - تأثير العوامل الحيوية Biological  Factors................................110

    -تأثيرات المجموعات الشجرية في الوسط.........................................112

    -تأثير المجموعات الشجرية في الظروف المناخية و الأرضية و الفيزيوغرافية.112

    -العوامل الخضرية..................................................................114

    -الإشعاع الشمسي و الضوء.......................................................115

    -الحرارة الجوية......................................................................116

    حركة الرياح..........................................................................117

    -الرطوبة الجوية.....................................................................118

    -العوامل الطبوغرافية و توزع النبت الحراجي في سورية..........................118

    -التعاقب الحراجي وتدهور الغابات Forestry successionلقثيشفهىationession and Forest detiruration  سوريال الساحلية____________________________________________________________________.....................121

    -تعريف التعاقب الحراجي..........................................................121

    -أنواع التعاقب الحراجي: ..........................................................121

    *التعاقب الأولي.....................................................................121

    *التعاقب الثانوي.....................................................................122

    *التعاقب التقدمي....................................................................124

    *التعاقب التراجعي..................................................................124

    -أسباب تدهور النبت الحراجي...............................................124-126

     

    الفصل الرابع: تنمية الأشجار الحراجية وتربيتها وتحسينها Silviculture...127

    - علم تنمية الأشجار وتربيتها وأهدافه الميدانية...................................127

    -طرق إكثار الأشجار الخشبية.....................................................128

    *طريقة الغابات العالية..............................................................128

    *الطريقة الجمية.....................................................................128

    -أهم طرق التنمية لمجاميع الأشجار و الغابات..................................128

    *طريقة القطع الكامل مع التكاثر الطبيعي........................................128

    *طريقة الشجرة البذرية..............................................................129

    *طريقة الانتخاب....................................................................130

    *طريقة الغابة الوقائية...............................................................130

    *طريقة الغابة الجمية...............................................................131

    -عمليات القطع......................................................................131

    -عمليات القطع المتوسطة..........................................................132

    -التربية و التنمية وجودة الخشب............................................135-146

     

    الفصل الخامس: إدارة الغابات واستغلالها Forest Management and Forest Exploitation.........................................................147

    -تعريف إدارة الغابات...............................................................147

    -جودة الموقع و الإدارة.............................................................148

    -الاكتمال............................................................................149

    -جداول المحصول..................................................................151

    -النمو................................................................................152

    -استغلال الحراج (الغابات) .......................................................154

    -تعريف استغلال الحراج (الغابات) ...............................................154

    -تخطيط استغلال الغابة............................................................154

    *الاستقصاء الأولي للغابة..........................................................154

    *وضع خطة الاستغلال.............................................................158

    -تقانات (مراحل) استغلال الغابة............................................159-164

     

    الفصل السادس: المشاتل الحراجية والتشجير   Forest Nurseries and Afforestation  .................................................................165

    -تعريف علم المشاتل الحراجية.....................................................165

    -تعريف المشتل الحراجي...........................................................165

    -أنواع المشاتل الحراجية............................................................165

    -تأسيس المشتل الحراجي...........................................................166

    -إنتاج الغراس الحراجية.............................................................168

    -التشجير الحراجي Afforestation .............................................173

    -أنواع التشجير الحراجي............................................................173

    -مصدات الرياح.....................................................................173

    *التأثير الموضعي لمصدات الرياح................................................174

    *أنواع مصدات الرياح..............................................................175

    -إعادة استزراع منطقة بالأشجار Reforestation .............................175

    -تجديد المجموعة الشجرية.........................................................175

    -الإكثار الصناعي للأشجار الحراجية.............................................176

    -موقع مصدر البذور................................................................177

    -كمية البذور اللازمة................................................................177

    -كثافة التشجير......................................................................178

    -إستراتيجيات التشجير في المناطق الجافة.................................178-184

     

    الفصل السابع: علم الأخشاب و الصناعات الخشبية Wood Science and Wood Industries.............................................................185

    -تعريف علم الأخشاب..............................................................185

    -تعريف الخشب.....................................................................185

    - أنواع النباتات الخشبية والأخشاب................................................185

    - بنية الأخشاب.....................................................................186

    - التركيب الكيماوي للأخشاب وخواصها الفيزيائية والميكانيكية..................188

    - أنواع الأخشاب المصنعة ومنتجاتها.............................................190

    *الخشب المنشور...................................................................190

    *الخشب المعاكس...................................................................190

    *خشب اللاتيه.......................................................................190

    *الخشب المضغوط.................................................................190

    *الخشب الليفي المتوسط الكثافة (MDF) ........................................191

    *صناعة الورق......................................................................191

    - حفظ الأخشاب ومعالجتها........................................................193

     

    -الفحم الخشبي................................................................194-202

     

    المراجع References............................................................203

     

    المصطلحات...................................................................207-219

     

     

     

  • 18.
    Hameed, Mahmood
    Damascus University, Syria.
    Forestry and Forest Nersery (Work-book)2012 (uppl. 1)Bok (Övrigt vetenskapligt)
    Abstract [ar]

    الفهرس

     

    مقدمة...................................................................................... 7

     

    الجلسة العملية الأولى:

     كيفية تجفيف العينات الحراجية...................................................... 9

    الجلسة العملية الثانية:

    التعرف إلى الأنواع الحراجية المخروطية............................................ 13

    الجلسة العملية الثالثة:

    التعرف إلى الأنواع الحراجية عريضة الأوراق....................................... 25

    الجلسة العملية الرابعة:

    تابع التعرف إلى الأنواع الحراجية عريضة الأوراق.................................. 33

    الجلسة العملية الخامسة:

    تابع التعرف إلى الأنواع الحراجية عريضة الأوراق.................................. 43

     

    الجلسة العملية السادسة:

    تابع التعرف إلى الأنواع الحراجية عريضة الأوراق.................................. 49

    الجلسة العملية السابعة:

    تابع التعرف إلى الأنواع الحراجية عريضة الأوراق.................................. 65

     

    الجلسة العملية الثامنة:

    تابع التعرف إلى الأنواع الحراجية عريضة الأوراق.................................. 69

    الجلسة العملية التاسعة:

    تابع التعرف إلى الأنواع الحراجية عريضة الأوراق.................................. 77

    الجلسة العملية العاشرة:

    التعرف إلى الأنواع الحراجية من خلال شكل القلف لجذوعها........................ 83

    الجلسة العملية الحادية عشرة:

    المراحل العملية لإستغلال الغابة.................................................... 89

    الجلسة العملية الثانية عشرة:

    تطبيقات عملية لتحديد جودة الأخشاب............................................. 91

     

    الجلسة العملية الثالثة عشرة:

    التعرف إلى نماذج من الصناعات الخشبية.......................................... 93

    الجلسة العملية الرابعة عشرة:

    زيارة لمشتل حراجي................................................................ 99

     

    ملحق :

            I- صور ملونة للأنواع المدروسة................................................ 102

           II- الصفات التكنولوجية لأهم الأنواع الخشبية المحلية و المدخلة في سورية....... 151

           III- أهم منتجات الغابة غير الخشبية............................................ 171

          

    المراجع :

    المراجع العربية........................................................................... 175

    المراجع الأجنبية......................................................................... 177

     

  • 19.
    Fagerberg, Nils
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Industrin eller skogsägarna - vems behov ska styra?2012Ingår i: Ett brott i skogen? / [ed] Harald Holmberg, Skellefteå: Ord & Visor förlag , 2012, 1, 129-133 s.Kapitel i bok, del av antologi (Övrig (populärvetenskap, debatt, mm))
  • 20.
    Wagner, Leopold
    et al.
    Vienna University of Technology, Austria.
    Bader, Thomas K.
    Vienna University of Technology, Austria.
    Auty, David
    University of Aberdeen, UK.
    de Borst, Karin
    University of Glasgow, UK.
    Key parameters controlling stiffness variability within trees: a multiscale experimental–numerical approach2012Ingår i: Trees, ISSN 0931-1890, E-ISSN 1432-2285, Vol. 27, nr 1, 321-336 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Microstructural properties of wood vary considerably within a tree. Knowledge of these properties and a better understanding of their relationship to the macroscopic mechanical performance of wood are crucial to optimize the yield and economic value of forest stocks. This holds particularly for the end-use requirements in engineering applications. In this study the microstructure–stiffness relationships of Scots pine are examined with a focus on the effects of the microstructural variability on the elastic properties of wood at different length scales. For this purpose, we have augmented microstructural data acquired using SilviScan-3™ (namely wood density, cell dimensions, earlywood and latewood proportion, microfibril angle) with local measurements of these quantities and of the chemical composition derived from wide-angle X-ray scattering, light microscopy, and thermogravimetric analysis, respectively. The stiffness properties were determined by means of ultrasonic tests at the clear wood scale and by means of nanoindentation at the cell wall scale. In addition, micro-mechanical modeling was applied to assess the causal relations between structural and mechanical properties and to complement the experimental investigations. Typical variability profiles of microstructural and mechanical properties are shown from pith to bark, across a single growth ring and from earlywood to latewood. The clear increase of the longitudinal stiffness as well as the rather constant transverse stiffness from pith to bark could be explained by the variation in microfibril angle and wood density over the entire radial distance. The dependence of local cell wall stiffness on the local microfibril angle was also demonstrated. However, the local properties did not necessarily follow the trends observed at the macroscopic scale and exhibited only a weak relationship with the macroscopic mechanical properties. While the relationship between silvicultural practice and wood microstructure remains to be modeled using statistical techniques, the influence of microstructural properties on the macroscopic mechanical behavior of wood can now be described by a physical model. The knowledge gained by these investigations and the availability of a new micromechanical model, which allows transferring these findings to non-tested material, will be valuable for wood quality assessment and optimization in timber engineering.

  • 21.
    Bader, Thomas K.
    et al.
    Vienna University of Technology, Austria.
    Hofstetter, Karin
    Vienna University of Technology, Austria.
    Alfredsen, Gry
    Norwegian Forest and Landscape Institute, Norway.
    Bollmus, Susanne
    Georg-August-University of Göttingen, Germany.
    Microstructure and stiffness of Scots pine (Pinus sylvestris L) sapwood degraded by Gloeophyllum trabeum and Trametes versicolor Part I: Changes in chemical composition, density and equilibrium moisture content2012Ingår i: Holzforschung, ISSN 0018-3830, E-ISSN 1437-434X, Vol. 66, nr 2, 191-198 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Fungal degradation alters the microstructure of wood and its physical and chemical properties are also changed. While these changes are well investigated as a function of mass loss, mass density loss and changes in equilibrium moisture content are not well elucidated. The physical and chemical alterations are crucial when linking microstructural characteristics with macroscopic mechanical properties. In the present article, a consistent set of physical, chemical and mechanical characteristics is presented, which were measured on the same sample before and after fungal degradation. In the first part of this two-part contribution, elucidating microstructure/stiffness-relationships of degraded wood, changes in physical and chemical data are presented, which were collected from specimens of Scots pine (Pinus sylvestris) sapwood degraded by Gloeophyllum trabeum (brown rot) and Trametes versicolor (white rot) for up to 28 weeks degradation time. A comparison of mass loss with corresponding mass density loss demonstrated that mass loss entails two effects: firstly, a decrease in sample size (more pronounced for G. trabeum), and secondly, a decrease of mass density within the sample (more pronounced for T. versicolor). These two concurrent effects are interrelated with sample size and shape. Hemicelluloses and cellulose are degraded by G. trabeum, while T. versicolor was additionally able to degrade lignin. In particular because of the breakdown of hemicelluloses and paracrystalline parts of cellulose, the equilibrium moisture content of degraded samples is lower than that in the initial state.

  • 22.
    Bader, Thomas K.
    et al.
    Vienna University of Technology, Austria.
    Hofstetter, Karin
    Vienna University of Technology, Austria.
    Eberhardsteiner, Josef
    Vienna University of Technology, Austria.
    Keunecke, Daniel
    ETH Zürich, Switzerland.
    Microstructure–Stiffness Relationships of Common Yew and Norway Spruce2012Ingår i: Strain, ISSN 0039-2103, E-ISSN 1475-1305, Vol. 48, nr 4, 306-316 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Yew (Taxus baccata L.) exhibits among conifers a unique macroscopic elastic behaviour. For example, it shows a comparatively low longitudinal elastic modulus related to its comparatively high density. We herein explore the microstructural origin of these peculiarities, aiming at the derivation of microstructure–stiffness relationships. We measure stiffness properties of yew at different hierarchical levels and compare them to corresponding stiffnesses of Norway spruce (Picea abies [L.] Karsten). Cell wall stiffness is investigated experimentally by means of nanoindentation in combination with microscopy and thermogravimetric analysis. On the macroscopic level, we perform uniaxial tension and ultrasonic tests. Having at hand, together with previously reported stiffnesses, a consistent data set of mechanical, chemical and physical properties across hierarchical levels of wood, we discuss influences of microstructural characteristics at different scales of observation. Moreover, a micromechanical model is applied to predict trends of effects of the microstructure on the investigated stiffness properties. On the cell wall level, particularly, the amount of cellulose and its orientation – which was earlier reported to be distinctly different for yew and spruce – result in differences between the two considered species. On the macroscopic scale, model predicted effects of the annual ring structure on transverse stiffness and shear stiffness are found to be smaller than effects of the microfibril angle and mass density.

  • 23.
    de Borst, Karin
    et al.
    Vienna University of Technology, Austria.
    Bader, Thomas K.
    Vienna University of Technology, Austria.
    Wikete, Christoph
    Vienna University of Technology, Austria.
    Microstructure-€“stiffness relationships of ten European and tropical hardwood species2012Ingår i: Journal of Structural Biology, ISSN 1047-8477, E-ISSN 1095-8657, Vol. 177, nr 2, 532-542 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Hardwood species exhibit a huge anatomical variability. This makes them perfect study objects for exploring relations between structural features at different length scales and corresponding stiffness properties of wood. We carry out microscopic analysis, nanoindentation tests, as well as macroscale ultrasonic and quasi-static tension tests and build a complete set of microstructural and corresponding micromechanical data of ten different (European and tropical) hardwood species. In addition, we apply micromechanical modeling to further elucidate the individual influences of particular structural features, which might appear only in a superimposed manner in experiments. The test results confirm the dominant influences of the microfibril angle on the stiffness at cell wall level and of density at the macroscopic scale. Vessels and ray cells affect the macroscopic stiffness of the wood tissue not only through their content, but also through their arrangement and shape: A ring-porous structure results in comparably higher longitudinal but lower radial stiffness than a diffuse-porous one. As for ray cells, large and particularly compactly shaped bundles might reduce the stiffness in tangential direction because of the fiber deviations they cause. Moreover, vessel and ray content might affect the relation between nanoindentation modulus and density-corrected macroscopic longitudinal stiffness.

  • 24.
    Gamstedt, E. Kristofer
    et al.
    Uppsala University.
    Bader, Thomas K.
    Vienna University of Technology, Austria.
    de Borst, Karin
    University of Glasgow, UK.
    Mixed numerical–experimental methods in wood micromechanics2012Ingår i: Wood Science and Technology, ISSN 0043-7719, E-ISSN 1432-5225, Vol. 47, nr 1, 183-202 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Mixed numerical–experimental methods are increasingly used in various disciplines in materials science, recently also in wood micromechanics. Having a relatively irregular microstructure, direct interpretation of mechanical tests is not always possible since structurally specific properties are quantified rather than general material properties. The advent of combined numerical–experimental methods unlocks possibilities for a more accurate experimental characterization. A number of examples of mixed methods pertaining to both emerging experimental techniques and physical phenomena are presented: nano-indentation, moisture transport, digital-image correlation, dimensional instability and fracture of wood-based materials. Successful examples from other classes of materials are also presented, in an attempt to provide some ideas potentially useful in wood mechanics. Some general pit-falls in parameter estimation from experimental results are also outlined.

  • 25.
    Eitelberger, Johannes
    et al.
    Vienna University of Technology, Austria.
    Bader, Thomas K.
    Vienna University of Technology, Austria.
    de Borst, Karin
    Vienna University of Technology, Austria.
    Jäger, Andreas
    Vienna University of Technology, Austria.
    Multiscale prediction of viscoelastic properties of softwood under constant climatic conditions2012Ingår i: Computational materials science, ISSN 0927-0256, E-ISSN 1879-0801, Vol. 55, 303-312 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper covers the development and validation of a multiscale homogenization model for linear viscoelastic properties of wood. Starting point is the intrinsic structural hierarchy of wood, which is accounted for by several homogenization steps. Using the correspondence principle, an existing homogenization model for the prediction of elastic properties of wood is adapted herein for upscaling of viscoelastic characteristics. Accordingly, self-consistent, Mori–Tanaka, and unit-cell-based techniques are employed, leading to pointwise defined tensorial creep and relaxation functions in the Laplace-Carson domain. Subsequently, these functions are back-transformed into the time domain by means of the Gaver-Stehfest algorithm. With this procedure the orthotropic macroscopic creep behavior of wood can be derived from the isotropic shear behavior of the lignin-hemicellulose phase. A comparison of model predictions for viscoelastic properties of softwood with corresponding experimentally derived values yields very promising results and confirms the suitability of the model.

  • 26.
    Nilsson, Daniel
    et al.
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Nylinder, Mats
    The Swedish University of Agricultural Sciences.
    Fryk, Hans
    The Swedish University of Agricultural Sciences.
    Nilsson, Jonaz
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Mätning av grotflis2012Rapport (Övrigt vetenskapligt)
    Abstract [sv]

    Handeln av grotflis, flis från grenar och toppar vid slutavverkning, har ökatkraftigt under de senaste åren. Inmätningen sker vanligtvis vidmottagningsplatsen och betalningen sker vanligen utifrån energiinnehåll meduppgift om fukthalt.Syftet med denna studie har varit att jämföra olika mätmetoder för grotflissom bygger på volym, vikt och olika sätt att uppskatta fukthalten. Den metodsom antas som facit bygger på 10 prover per container vilket innebär 30prover per leverans. Detta ”facit” har jämförts med sex alternativa sätt attberäkna lassens energivärde. En av metoderna är den som tillämpas av VMFSyd och en annan är en metod som bygger på en finsk modell att uppskattafukthalten. Studien är avgränsad till 44 leveranser grotflis, i huvudask frånbarrträd, under vinter och sommarförhållanden och transporten har skett iekipage om tre fliscontainrar.Medelfukthalten för de vinterkörda leveranserna bestämdes via 10 prov percontainer, LNU/SLU, till 39,3 % medan VMF Syd uppmätte enmedelfukthalt på 38,7 %, via den finska metoden uppskattades fukthalten förde vinterkörda leveranserna till 45,5 %. Medelfukthalten för desommarkörda leveranserna bestämdes av LNU/SLU till 27,9 %, av VMFSyd till 27,0 % meden uppskattningen via den finska metoden gav enmedelfukthalt på 30 %.De vinterkörda ekipagen hade enligt det antagna facit, LNU/SLU, ettenergiinnehåll i medeltal på 104,2 MWh medan energiinnehållet enligtfukthalten från VMF blev energiinnehållet i medeltal 105,7 MWh och dåfukthalten bestämdes med den finska metoden blev energiinnehållet imedeltal 90,8 MWh. För de sommarkörda leveranserna blev energiinnehålleti medeltal 110,8 MWh enligt LNU/SLU, 112,5 MWh enligt VMF Syd och105,7 MWh enligt den finska metoden.När det gäller de olika mätmetoderna visade det sig att M6, energivärde direkt ifrån mätsedel, var den bästa med en kvotspridning på 6,4 % ijämförelse med antaget facitvärde beräknat enligt LNU/SLU. Anledningentill detta är att denna mätning baseras på av fukthalten och beräknat effektivtvärmevärde för varje enskild leverans medan de andra bygger på ett beräknat”erfarenhetstal” för energiinnehåll per ton respektive per m3s förleveranserna i studien. Om mätningen istället baseras på erfarenhetstalistället för fukthaltsmätning visar resultaten att volymmätning ger en mindrekvotspridning, runt 10 %, jämfört med viktbaserad mätning där kvotspridningen hamnar på ca 17 % jämfört med facit. Fukthaltsmätningenligt den finska metoden ger en kvotspridning på ca 15 %.Volymminskningen under transport för alla leveranser i studien uppmättes imedeltal till strax över 2 % och resultaten visar också att den störstavolymminskningen, ca 70 %, sker redan under de första kilometrarna.Skillnaden mellan VMFs volymmätning och den mer noggrannavolymmätningen utförda av LNU/SLU visade sig vara endast 0,5 %. Men dålassen krattats för att möjliggöra denna mätning har även VMFs inmätningförenklats.

  • 27.
    Nilsson, Bengt
    et al.
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Thörnqvist, Thomas
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Potential of forest fuel in the county of Småland: the woodshed of Sweden2012Ingår i: World Bioenergy 2012, 29-31 May, Jönköping, Sweden, 2012Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    The county of Småland in southern Sweden is often labeled the woodshed of Sweden. The largest potential to increase has forest fuel from final fellings, in the form of logging residuals (branches and tops) and stumps. This study shows that logging residuals, stumps and by-products from sawmills have the potential to contribute with 5.9 TWh per year, equivalent to 88% of the total use of wood fuel in Småland today. The results also show distribution of forest fuel on municipality level.

  • 28.
    Blom, Åsa
    et al.
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Thörnqvist, Thomas
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Bergström, Mikael
    Presence of longitudinal cracks in planks from storm-felled pine (Pinus sylvestris L.) and spruce (Picea abies (L.) Karst.)2012Ingår i: Wood Material Science & Engineering, ISSN 1748-0272, Vol. 7, nr 4, 237-241 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    After the severe storm Gudrun in southern Sweden in 2005, a quantitative study was done in order to investigate the presence of lengthwise crack on planks taken from storm-felled trees in southern Sweden, compared to planks from standing trees not subjected to this storm (central Sweden). The main yield from each log was examined. In total, 1087 pine (Pinus sylvestris) planks and 3626 spruce (Picea abies) planks from the storm-struck area were investigated and compared to 1953 spruce and 2000 pine planks from trees outside the storm-struck area. The examination of cracks was done visually on dried planks. For pine, 51.7% of the planks from storm-felled trees had a total length longer than 0.5 m, compared to 7.3% for the reference material. As for spruce, 11.0% of the planks from storm-felled trees had a total crack length of more than 0.5 m, compared to the reference material where 2.2% had cracks longer than 0.5 m. The results show that the storm-felled trees had more longitudinal cracks than the reference material and that pine was more likely to develop storm-related cracks than spruce.

  • 29.
    Eliasson, Lars
    et al.
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Gustafsson, Åsa
    Linnéuniversitetet, Fakultetsnämnden för ekonomi och design, Ekonomihögskolan, ELNU.
    Quality deficiencies regarding softwood in the pre-fabrication industry for single-family timber houses2012Ingår i: Wood Material Science & Engineering, ISSN 1748-0272, E-ISSN 1748-0280, Vol. 8, nr 1, 53-63 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The members of the pre-fabricated single-family house industry perceive problems securing the quality of incoming material. Thus the implication is that they need to carry out a quality inspection and adjust the softwood timber as it arrives at their facilities in order to fit the production. Furthermore, due to the intense competition among companies in the pre-fabrication industry, there is a focus on reducing non-value-adding activities such as deficiencies. Consequently, the purpose of this study is to propose a number of propositions regarding quality deficiencies in softwood timber for the pre-fabrication of single-family houses. This study, conducted through interviews based on the theoretical aspects of properties, quality inspection and quality deficiency formulates seven fundamental propositions regarding quality deficiencies in this industry. The main differences among the companies studied are their purchased volume and extent of information and communication technology support in production. This fundamental description of quality deficiencies regarding softwood for the pre-fabrication of single-family houses will enable companies to focus on quality issues with their raw-material suppliers and thereby increase the competitiveness of softwood timber as a construction material in the industry.

  • 30.
    Hameed, Mahmood
    et al.
    Damascus University, Syria.
    Mansour, Rita
    Remediation of Environmental Hazards in Olive Oil mill wastewater by using the aeration2012Ingår i: Minia Journal of Agricultural Research and Development, ISSN 1110-0257, Vol. 32, nr 2, 211-221 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The liquid wastes come from milling the olive fruits, which are called the Olive Mill Wastewater, are disposed directly without any treatment. This causes a pollution of soil, groundwater, lakes, rivers and seas; it makes negative consequences on the elements of the ecological systems besides. Therefore, the treatment of these wastes and the ability to reusing them are urgent and necessary. The areas planted with olive trees yearly increase in Syria, this means that the annual average of olive oil production increases too. This causes the increasing of the main wastes average that comes from milling the olive fruits (The Olive Mill Wastewater). This investigation has established the Possibility of Rremediation of Environmental Hazards in Olive Oil mill wastewater by using the aeration, which can degrade the total polyphenol compounds in Olive Oil mill wastewater, which have bad effects on aqua environment to 77,76 % during 15 days. 

  • 31.
    Löf, Magnus
    et al.
    Swedish University of Agricultural Sciences, Sweden.
    Brunet, Jörg
    Swedish University of Agricultural Sciences, Sweden.
    Hickler, Tomas
    Goethe-University Frankfurt, Germany.
    Birkedal, Maria
    Södra Skog, Sweden.
    Jensen, Anna M.
    Oak Ridge National Laboratory, USA.
    Restoring broadleaved forests in southern Sweden as climate changes2012Ingår i: A Goal-Oriented Approach to Forest Landscape Restoration / [ed] Stanturf, J., Madsen, P. and Lamb, D. (Eds.), Springer, 2012, 373-391 s.Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    Temperate broadleaved forests in southern Sweden are important for biodiversity and policies have, so far, been concentrated on protecting the few valuable forests that still remain. This approach is now being challenged by rapid climate change. Using a vegetation model, we present transient and potential long-term predictions for changes in the natural distribution of different tree species and forest composition. Our model analyses show that temperate broadleaved tree species will be able to be established further north than their present distribution. In addition, this region will probably be an area of high species turnover, with the loss of boreal species and gains of temperate species. New broadleaved forests need to be restored in order to enhance reintegration. Current forest policies may not be relevant under a climate change scenario. Research is needed in climate change impacts on species and habitats, habitat restoration, migration of species, alternative silvicultural systems and efficient regeneration systems. It would probably be too expensive for the society to rely only on governmental resources for sustainable landscape level restorations programs. Instead a pragmatic approach, which considers the economic aspects of private forest owners, as well as other goals, should be adopted. In addition, policies must be based on a holistic understanding of the interactions between management, climate change and biodiversity.

  • 32.
    Jensen, Anna M.
    et al.
    Swedish University of Agricultural Sciences.
    Götmark, Frank
    University of Gothenburg.
    Löf, Magnus
    Swedish University of Agricultural Sciences.
    Shrubs protect oak seedlings against ungulate browsing in temperate broadleaved forests of conservation interest: a field experiment2012Ingår i: Forest Ecology and Management, ISSN 0378-1127, Vol. 266, 187-193 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In many oak-rich temperate broadleaved forests of conservation value, high ungulate browsing pressure restricts oak regeneration. We examined the protection of oak (Quercus sp.) seedlings from browsing provided by naturally occurring shrubs in 10 forests across southern Sweden over 3 years. We planted oak seedlings in four plots in each forest; two with naturally regenerated shrubs and two with no shrubs. Ungulate browsers were excluded from two plots at each site, one with and one without shrubs. Fencing provided the best protection against ungulate browsers for the seedlings. The probability of a seedling being browsed (browsing frequency) was approximately 20% units lower for individuals growing among shrubs than for individuals growing in the absence of shrubs. When browsing did occur, the intensity (measured as a reduction in height growth) was significantly lower for seedlings in shrubs. Regression analyses showed that browsing frequency increased on seedlings in tall shrubs, and decreased on seedlings that had been browsed previously. Browsing intensity decreased if the seedling grew in tall and dense shrubs. Browsing frequency and intensity increased on oak seedlings that over topped the shrub canopy. Increased abundance of the prickled Rubusidaeus and Rubusfruticosus coll. in plots with shrubs did not affect browsing frequency and intensity. Two and a half years after planting, oak seedling mortality increased by the presence of shrubs. Although shrubs restricted oak seedling growth, we conclude that shrubs initially facilitated oak regeneration by concealment, and subsequently by numeric dilution. Shrubs may be used to reduce browsing damages if long-term evaluation indicates a net positive outcome for oak survival and growth.

  • 33. Bianchi, S
    et al.
    Placencia Peña, M.I
    Ganne-Chédeville, C
    Pichelin, F
    Sandberg, Dick
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Softwood strand-boards manufacturing without adhesive using linear friction welding technology2012Ingår i: Current and Future Trends of Thermo-Hydro-Mechanical Modification of Wood., Nancy University , 2012, 142-143 s.Konferensbidrag (Refereegranskat)
  • 34.
    Blom, Åsa
    et al.
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Johansson, Jimmy
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Sivrikaya, Hüseyin
    Some factors influencing susceptibility to discoloring fungi and water uptake of Scots pine (Pinus sylvestris), Norway spruce (Picea abies) and Oriental spruce (Picea orientalis) 2012Ingår i: Wood Material Science & Engineering, ISSN 1748-0272, Vol. 8, nr 2, 139-144 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The heartwood and sapwood from Scots pine (PS), Norway spruce (PA), and Oriental spruce (PO) were tested for susceptibility to discoloring fungi and water uptake. In addition, annual ring width and density were measured. The methods used were Mycologg for testing growth of fungi and a modified version of EN 927-5 to investigate water uptake. For pine, the heartwood showed a lower water uptake and no discoloring fungi growing in the tests. The heartwood had a significantly higher density and smaller annual ring width than the sapwood. In PA the heartwood had significantly lower discoloration than sapwood. The total water uptake in g/m2 was significantly higher in sapwood, but not the calculated moisture content. As for wood properties, the density was significantly higher in sapwood compared to heartwood, although there were no differences in annual ring width. Regarding PO, differences in water uptake could be seen between sapwood and heartwood although the densities were similar. These results show that susceptibility to discoloring fungi and water uptake is hard to correlate to a single inherent property when looking at different wood species.

  • 35.
    Hameed, Mahmood
    et al.
    Damascus University, Syria.
    Ayoub, Monier
    Aboud, Nesreen
    Study of Mechanical properties of River red gum Eucalyptus camaldulensis Dehn in Damascus-Daraa Road.2012Ingår i: Minia Journal of Agricultural Research and Development., ISSN 1110-0257, Vol. 32, nr 1, 37-64 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The River red gum (Eucalyptus camaldulensis Dehn. ) is found in a lot of places in Syria, and the trees in Damascus- Daraa Road are in  good height, diameter and growth, so that we aimed to study some of the mechanical properties of its wood related to the most important modern uses of this wood in industry.

    The study was done over Three trees, and three trunk masses of wood about 70 cm were taken from each tree from the beginning, the breast and the middle of the tree .

    The results show that the wood of Rever red gum has the following mechanical properties:

    -     The compression strength parallel to grain is medium (39.6 N/mm2), therefore, it is good in industries uses.

    -     The bending factor is weak (1.44) , and its coherence is medium  (2.27).

    -          The risistance of tensile strength was 40 N/mm2 .

    -          Hardness (Janka) was 38.3 N/mm2.

    So that we find out that the wood of River red gum is good and could be considered as a good wood with various uses and this spice is considered one of the promosing trees in our country for afforestration in zones like the stydy zones.

    As for the variance, ther are significant effects of tacking masses from tree on the physical and mechanical properties of the wood.

  • 36.
    Hameed, Mahmood
    et al.
    Damascus University, Syria.
    Ayoub, Monier
    Aboud, Nesreen
    Study of Physical properties of River red gum Eucalyptus camaldulensis Dehn.  in Damascus-Daraa Road.2012Ingår i: Minia Journal of Agricultural Research and Development., ISSN 1110-0257, Vol. 32, nr 1, 17-36 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The trees of River Red Gum in Damascus- Daraa Road are in a good height, diameter and growth, so that we aimed to study some of the physical properties of its wood related to the most important modern uses of this wood in industry.

    The study was done over Three trees, and three trunk masses of wood about 70 cm were taken from each tree from the beginning, the breast and the middle height of the tree.

    The results show that the wood of Rever red gum has the following physical properties:

    • It is hard, in which the density was 0.63 g/cm3, and this means that it is resistant to mechanical stress and sutable for using in building and engineering constructions.
    • The shrinkage is high.
    • As for the variance, there are significant effects of tacking masses from tree on the physical properties of the wood.
  • 37.
    Blomqvist, Lars
    et al.
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Johansson, Jimmy
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Sandberg, Dick
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    Kifetew, Girma
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    The influence of individual veneer orientation on the shape stability of planar lamination2012Ingår i: Current and Future Trends of Thermo-Hydro-Mechanical Modification of Wood. Opportunities for new markets? / [ed] Mathieu Pétrissans and Philippe Gérardin, Nancy, France, 2012, 160-162 s.Konferensbidrag (Refereegranskat)
  • 38.
    Hameed, Mahmood
    et al.
    Damascus University, Syria.
    Mosseily, Ihssan
    The Possibility of Producing Particleboard from Wastes by-Product of Olives and Determination of its physical- and mechanical Properties2012Ingår i: Minia Journal of Agricultural Research and Development, ISSN 1110-0257, Vol. 32, nr 6, 1087-10104 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This investigation has established the possibility of producing Particleboard from Byrene (waste after the oil has been extracted from the second time with Naphtha). This product has good physical-[moisture content (6.1%). density (0.73). absorption and cross-swelling after 2 hours (29.8%:12.6%) and after 24 hours (40.1%:19.1%)] and mechanical properties [binding strength (8.3 N/mm2) and cross-tensile strength (0.23 N/mm2)] according to European Norms and is very economical. 

  • 39.
    Navi, Parviz
    et al.
    EPFL, École Polytechnique Fédérale de Lausanne.
    Sandberg, Dick
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Institutionen för teknik, TEK.
    The thermo-hydro-mechanical processing of wood.2012 (uppl. 1)Bok (Refereegranskat)
    Abstract [en]

    The fabrication of wood-derived products is numerous and is continuously being developed thanks to its unique advantages: widespread availability, natural renewal, favorable ecological assessment and its flexibility of implementation. Moreover, the polymeric components of wood together with its porous structure confer to it a faculty for transformation exceeding that of other materials.

    Since the dawn of civilization wood has been used in its natural state. Only recently has wood been developed to form a range of products that are increasingly functional, based on a combination of performance and sustainability requirements.

    Since the beginning of the last century, the advance of knowledge on this topic has been constant, mainly through the efforts of systematic scientific research and new types of applications.

    Around the middle of the last century the preliminary work addressing the science and technology of wood was published. The current success in the understanding of its material properties, chemistry, physics and advances obtained in materials science, together with modeling techniques, provided the means for engineers and researchers to be able to engineer wood as a material and to produce new materials and products under controlled processing conditions.

    The intention to overcome difficulties in the processing technologies, as related to wood, requires an interdisciplinary approach. A close co-operation between scientific disciplines such as the anatomy of wood, physics, chemistry and mechanics makes it possible for each to contribute a constructive and complementary part in order to evolve, together, the technologies that relate to the various wood treatments, such as, for example - conservation, drying, machining, shaping and joining, etc.

    One of the emerging eco-friendly treatment methods is the combined use of temperature, moisture and mechanical action, the so called Thermo-Hydro-Mechanical (THM) treatment.  THM processing is implemented to improve the intrinsic properties of wood, to produce new materials, and in order to acquire a form and functionality desired by engineers without changing the eco-friendly nature of the material. These processes can be divided into two major categories; Thermo-Hydro (TH) treatments and Thermo-Hydro-Mechanical (THM) treatments.

    As we pointed out above, wood consists of natural polymeric chains, connecting to each other by hydrogen bands, and in certain parts by covalent bonds. The hydrogen bond is at the origin of its properties to transformation. For example, when wood is put under thermo-hydrous conditions, allowing for the softening of its amorphous components, it can easily deform which makes it possible to consider the application of a large number of industrial processes such as molding, densification, surface densification, bending, shaping, drying at high temperature, etc. Nevertheless, the application of high temperature, however, with or without moisture can damage mechanically, and modify chemically, the polymeric components of wood.

    The intention to gather together in one book the key elements of the chemical degradation of wood constituents under TH processing, the Thermo-Hydro, the Thermo-Hydro-Mechanical behavior, as well as a selection of the principal technologies implemented in TH/THM treatments, constitutes the primary reason of this edition. This work is intended for researchers, professionals of timber construction, as well as students studying the science of materials, wood technology and processing, civil engineering and architecture. This work is not exhaustive or a reference, but intends to deliver an outline of the scientific disciplines necessary to apprehend the technologies of wood THM and its behavior during treatment, as well as during its use.

    This work consists of 11 chapters. The first chapter is devoted to the reasons for TH/THM processing.  The ancient treatments of wood by THM processing are discussed in the second chapter. It is shown that different heat treatment processes have been used to improve the performance of wood and that the use of these processes dates back many thousands of years. The description of the structure and the chemical composition of the components of wood are given in the third chapter. In the fourth chapter, the explanation and modeling of certain THM behaviors of wood is presented. In the first part, the small and large deformations of wood are described, and the constitutive equations of elastic linear, as well as elastic nonlinear behavior of wood, are derived. In the second part the viscoelastic behavior of wood under ambient temperature, constant and variable humidity is described. In the chapter five, the behavior of THM of wood under variable moisture and temperatures (as high as 200°C), is examined by considering that during the processing, at high temperatures, the components of wood undergo certain chemical modifications. In this chapter the effects of the processing parameters: temperature, moisture content and time, on the THM wood characteristics are discussed. The sixth chapter is devoted to the processing of wood densification by THM treatment. In the first part of this chapter various THM wood densification processing methods are discussed and the machines that have been developed in different countries corresponding to open, closed, and mixed processing, are illustrated. In the rest of this chapter the origin and mechanisms of the shape memory and fixation of compression-set by THM treatment are discussed. Chapters seven and eight are devoted respectively to the wood welding by friction techniques and wood surface densification techniques. In both chapters different techniques are discussed and the problems related to these different ‘open systems’ are explained.

    In the recent decades developments in the area of heat treatment have accelerated considerably. At the present time many countries have developed their own wood TH treatments. In chapter nine most of these processing methods are presented and discussed. In chapter ten different wood bending processes: bending of solid-wood, laminated wood bending and other methods like green wood bending and kerfing are presented and different techniques discussed. Also, the theory of solid wood bending is explained. This chapter gives a demonstration of solid wood bending in the laboratory and at industrial levels. Finally, a selection of technologies is presented in the eleventh chapter on the fabrication of reconstituted wood, namely: Fiberboards, Particle boards and panels made of veneers.

    For the benefit wood engineers and other people with an interest in this fascinating industry, we hope that the availability of this material as printed book will provide an understanding of all the fundamentals involved in TH and THM processing of wood.

  • 40.
    Alfredsen, Gry
    et al.
    Norwegian Forest and Landscape Institute, Norway.
    Bader, Thomas K.
    Vienna University of Technology, Austria.
    Dibdiakova, Janka
    Norwegian Forest and Landscape Institute, Norway.
    Filbakk, Tore
    Norwegian Forest and Landscape Institute, Norway.
    Bollmus, Susanne
    Georg-August-University of Göttingen, Germany.
    Hofstetter, Karin
    Vienna University of Technology, Austria.
    Thermogravimetric analysis for wood decay characterisation2012Ingår i: European Journal of Wood and Wood Products, ISSN 0018-3768, E-ISSN 1436-736X, Vol. 70, nr 4, 527-530 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The paper focuses on the use of thermogravimetric analysis (TGA) as a fast method for estimating the change of lignocellulosic materials during fungal degradation in laboratory trials. Traditionally, evaluations of durability tests are based on mass loss. However, to gain more knowledge of the reasons for differences in durability and strength between wooden materials, information on the chemical changes is needed. Pinus sylvestris sapwood was incubated with the brown rot fungusGloeophyllum trabeum and the white rot fungus Trametes versicolor. The TGA approach used was found to be reproducible between laboratories. The TGA method did not prove useful for wood deteriorated by white rot, but the TGA showed to be a convenient tool for fast estimation of lignocellulosic components both in sound wood and wood decayed by brown rot.

  • 41.
    Adamopoulos, Stergios
    et al.
    Technological Education Institute of Larissa, Greece.
    Wimmer, Rupert
    Georg-August-University Göttingen, Germany.
    Milios, Elias
    Democritus University of Thrace, Greece.
    Tracheid length – growth relationships of young Pinus brutia grown on reforestation sites2012Ingår i: IAWA Journal, ISSN 0928-1541, Vol. 33, nr 1, 39-49 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Brutia pine (Pinus brutia Ten.) reforestations have been successfully used for decades in restoration of degraded forest ecosystems in Greece. The future purpose of these reforestations might expand to include wood utilisation. This study provides information on tracheid length of juvenile brutia pine aged 14–22 years grown on good and medium sites in Northeastern Greece. In addition, relationships among ring width, latewood proportion, wood density, and tracheid length were evaluated by using Causal Correlation Analysis. Similar mean tracheid length values were found for good and medium sites. Radial variability of tracheid length was similar on the good and medium sites, showing the typical increase in the juvenile phase. On both site types, latewood proportion showed a strong and positive relationship with wood density. Unexpectedly and only on the good sites, a significant positive relationship was found between ring width and wood density. On the medium sites, tracheid length was negatively related to fast growth and positively to high wood density. Tracheid length on the good sites was correlated only with latewood proportion with a weak positive relationship. The overall results may provide opportunities to better understand the quality of small-dimension timber of brutia pine and to better utilise it.

  • 42.
    Adamopoulos, Stergios
    Technological Educational Institute of Larissa, Greece.
    Νέες τεχνολογίες συγκοµιδής δασικών προϊόντων: [New technologies for harvesting forest products]2012Ingår i: "Harvesting, Supply and Trade of Woody Biomass". Centre for Renewable Energy Sources and Saving (CRES) and Department of Forestry and Management of Natural Environment, TEI of Larissa, 19 October 2012, Karditsa, Greece, 2012Konferensbidrag (Övrigt vetenskapligt)
  • 43.
    Adamopoulos, Stergios
    et al.
    Technological Educational Institute of Larissa, Greece.
    Voulgaridis, Elias
    Aristotle University of Thessaloniki, Greece.
    Ποιότητα και μεταβλητότητα της δομής του ξύλουσε σχέση με την αξιοποίησή του: [Quality and variability of wood structure in relation to its utilization]2012Ingår i: Το Δάσος: Μια Ολοκληρωμένη Προσέγγιση: [The forest: An integrated approach] / [ed] Aristotélis Papageorgíou, Geórgios Karétsos, Geórgios Katsadorákis, WWF Greece , 2012, 213-227 s.Kapitel i bok, del av antologi (Övrigt vetenskapligt)
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