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Goran Stahl - One of the best experts on this subject based on the ideXlab platform.

  • biomass conversion factors density and carbon concentration by decay classes for dead wood of pinus sylvestris Picea Abies and betula spp in boreal forests of sweden
    Forest Ecology and Management, 2007
    Co-Authors: Frida Sandstrom, Hans Petersson, Nicholas Kruys, Goran Stahl
    Abstract:

    For estimating the amount of carbon (C) in dead wood, conversion factors from raw volume per decay class to dry weight were developed using three different classification systems for the species Norway spruce (Picea Abies L. Karst), Scots pine (Pinus sylvestris L.) and birch (Betula pendula Roth and B. pubescens Ehrh) in Sweden. Also the C concentration in dead wood (dry weight) was studied. About 2500 discs were collected from logs in managed forests located on 289 temporary National Forest Inventory (NFI) sample plots and in 11 strips located in preserved forests. The conversion factors were based on an extensive data compilation with a wide representation of different site-, stand-, species- and dead wood properties and were assumed to represent the population of fallen dead wood in Sweden. The density decreased significantly by decay class and the range in density for decay classes was widest for the NFI decay classification system, suggesting this to be the most suitable. The C concentration in dead wood biomass increased with increasing decay class and in average Norway spruce (Picea Abies) showed a lower C concentration than Scots pine (Pinus sylvestris). The average dead wood C store of Swedish forests was estimated to 0.85 Mg C/ha.

  • wood inhabiting cryptogams on dead norway spruce Picea Abies trees in managed swedish boreal forests
    Canadian Journal of Forest Research, 1999
    Co-Authors: Nicholas Kruys, Clas Fries, Bengt Gunnar Jonsson, Tomas Lamas, Goran Stahl
    Abstract:

    We surveyed the quantity and quality of dead Norway spruce (Picea Abies (L.) Karst.) trees and wood-inhabiting cryptogams in a managed boreal forest landscape in northern Sweden. Size and decay of dead trees was related to substrate utilization by wood-inhabiting species. Coarse woody debris (CWD) was surveyed along 34 strip transects. CWD and wood-inhabiting cryptogams were surveyed in eight circular plots at each site. A total of 6195 spruce CWD units occurred along strip transects and 809 spruce CWD units in circular plots. On average 2.2 m3/ha spruce CWD was found on the plots. The majority (63%) of the transect CWD units were <10 cm diameter and in early to intermediate decay stages. Sixty-eight wood-specific species of fungi, lichens, mosses, and hepatics occurred on the plots. Of these, 13 occurred on 5% of the 809 CWD units surveyed for wood-inhabiting species. Eight species occur on the Swedish red lists, indicating that such species are indeed uncommon in managed forests. Red-listed species show...

Patrick Perre - One of the best experts on this subject based on the ideXlab platform.

  • reaction wood drying kinetics tension wood in fagus sylvatica and compression wood in Picea Abies
    Wood Science and Technology, 2009
    Co-Authors: Asghar Tarmian, Romain Remond, Mehdi Faezipour, Ali Karimi, Patrick Perre
    Abstract:

    The drying kinetics of reaction woods in Picea Abies (compression wood) and Fagus sylvatica (tension wood) in comparison with their corresponding normal woods was investigated under constant convective drying conditions. Moisture profiles along the thickness of small flat-sawn boards taken from reaction and opposite wood zones were evaluated using a polychromatic X-ray system, a non-destructive method. The results revealed substantial differences in the drying behavior between the reaction and opposite woods. Both reaction woods represented slower drying rate than their matching normal woods mainly during the period of free water loss. However, the reaction and opposite woods reached the final moisture content (MC) of about 12% at the same time due to higher initial MC in the opposite woods. In the case of reaction wood, it took a longer time for the moisture profile to become approximately uniform. Overall, a more striking difference was observed in the drying behavior of compression and opposite wood in P. Abies. Some important anatomical differences like the cell and pit dimensions and their proportion give some explanations for these drying behaviors.

D. Kákoniová - One of the best experts on this subject based on the ideXlab platform.

  • galactoglucomannan from the secondary cell wall of Picea Abies l karst
    Carbohydrate Research, 2000
    Co-Authors: Peter Capek, Marta Kubackova, Juraj Alfoldi, Ladislav Bilisics, Desana Lišková, D. Kákoniová
    Abstract:

    Abstract The fine structural features of alkali-extracted galactoglucomannan composed of d -galactose, d -glucose and d -mannose in a 1:8:33 mol proportion from the secondary cell walls of Picea Abies L. Karst have been determined. Compositional and methylation analyses of the polymer, partial acid hydrolysis, as well as 1 H and 13 C NMR measurements of the polymer and products of partial acid hydrolysis confirmed a β-(1→4)-linked backbone of galactoglucomannan containing the segments of mannosyl residues (Man 2 , Man 3 , Man 4 , etc.) interrupted with the segments having both mannose and glucose residues, as well as the segments in which d -Glc p units can be adjacent to each other (Glc 2 ). Further, the low content of branching points (∼3%) at the positions of O-6, O-3 and O-2 of mannosyl and O-6 and O-3 of glucosyl residues, but preferably of mannosyl ones, indicates the presence of short side-chains terminated at position O-6 predominantly by d -galactose units as single stubs.

  • Galactoglucomannan from the secondary cell wall of Picea Abies L. Karst.
    Carbohydrate research, 2000
    Co-Authors: Peter Capek, Marta Kubackova, Juraj Alfoldi, Ladislav Bilisics, Desana Lišková, D. Kákoniová
    Abstract:

    The fine structural features of alkali-extracted galactoglucomannan composed of D-galactose, D-glucose and D-mannose in a 1:8:33 mole proportion from the secondary cell walls of Picea Abies L. Karst have been determined. Compositional and methylation analyses of the polymer, partial acid hydrolysis, as well as 1H and 13C NMR measurements of the polymer and products of partial acid hydrolysis confirmed a beta-(1-->4)-linked backbone of galactoglucomannan containing the segments of mannosyl residues (Man2, Man3, Man4, etc.) interrupted with the segments having both mannose and glucose residues, as well as the segments in which D-Glcp units can be adjacent to each other (Glc2). Further, the low content of branching points (approximately 3%) at the positions of 0-6, 0-3 and 0-2 of mannosyl and 0-6 and 0-3 of glucosyl residues, but preferably of mannosyl ones, indicates the presence of short side-chains terminated at position 0-6 predominantly by D-galactose units as single stubs.

Peter Capek - One of the best experts on this subject based on the ideXlab platform.

  • an acetylated galactoglucomannan from Picea Abies l karst
    Carbohydrate Research, 2002
    Co-Authors: Peter Capek, Juraj Alfoldi, Desana Lišková
    Abstract:

    A water-soluble galactoglucomannan composed of d-galactose, d-glucose, and d-mannose in 1:3:17 mole proportion has been isolated from the secondary cell walls of Picea Abies L. Karst. About 33% of the polysaccharide units were substituted by acetyl groups. Structural studies of the polymer indicated a β-(1→4)-linked glucomannopyranosyl backbone with a low content of branch points at O-6 of mannosyl and glucosyl residues. A preference for mannosyl groups indicates the presence of a single d-galactosyl unit side-chain. About half of the mannose residues were O-acetylated at C-2 and C-3 in 1.7:1 mole proportion.

  • galactoglucomannan from the secondary cell wall of Picea Abies l karst
    Carbohydrate Research, 2000
    Co-Authors: Peter Capek, Marta Kubackova, Juraj Alfoldi, Ladislav Bilisics, Desana Lišková, D. Kákoniová
    Abstract:

    Abstract The fine structural features of alkali-extracted galactoglucomannan composed of d -galactose, d -glucose and d -mannose in a 1:8:33 mol proportion from the secondary cell walls of Picea Abies L. Karst have been determined. Compositional and methylation analyses of the polymer, partial acid hydrolysis, as well as 1 H and 13 C NMR measurements of the polymer and products of partial acid hydrolysis confirmed a β-(1→4)-linked backbone of galactoglucomannan containing the segments of mannosyl residues (Man 2 , Man 3 , Man 4 , etc.) interrupted with the segments having both mannose and glucose residues, as well as the segments in which d -Glc p units can be adjacent to each other (Glc 2 ). Further, the low content of branching points (∼3%) at the positions of O-6, O-3 and O-2 of mannosyl and O-6 and O-3 of glucosyl residues, but preferably of mannosyl ones, indicates the presence of short side-chains terminated at position O-6 predominantly by d -galactose units as single stubs.

  • Galactoglucomannan from the secondary cell wall of Picea Abies L. Karst.
    Carbohydrate research, 2000
    Co-Authors: Peter Capek, Marta Kubackova, Juraj Alfoldi, Ladislav Bilisics, Desana Lišková, D. Kákoniová
    Abstract:

    The fine structural features of alkali-extracted galactoglucomannan composed of D-galactose, D-glucose and D-mannose in a 1:8:33 mole proportion from the secondary cell walls of Picea Abies L. Karst have been determined. Compositional and methylation analyses of the polymer, partial acid hydrolysis, as well as 1H and 13C NMR measurements of the polymer and products of partial acid hydrolysis confirmed a beta-(1-->4)-linked backbone of galactoglucomannan containing the segments of mannosyl residues (Man2, Man3, Man4, etc.) interrupted with the segments having both mannose and glucose residues, as well as the segments in which D-Glcp units can be adjacent to each other (Glc2). Further, the low content of branching points (approximately 3%) at the positions of 0-6, 0-3 and 0-2 of mannosyl and 0-6 and 0-3 of glucosyl residues, but preferably of mannosyl ones, indicates the presence of short side-chains terminated at position 0-6 predominantly by D-galactose units as single stubs.

Desana Lišková - One of the best experts on this subject based on the ideXlab platform.

  • an acetylated galactoglucomannan from Picea Abies l karst
    Carbohydrate Research, 2002
    Co-Authors: Peter Capek, Juraj Alfoldi, Desana Lišková
    Abstract:

    A water-soluble galactoglucomannan composed of d-galactose, d-glucose, and d-mannose in 1:3:17 mole proportion has been isolated from the secondary cell walls of Picea Abies L. Karst. About 33% of the polysaccharide units were substituted by acetyl groups. Structural studies of the polymer indicated a β-(1→4)-linked glucomannopyranosyl backbone with a low content of branch points at O-6 of mannosyl and glucosyl residues. A preference for mannosyl groups indicates the presence of a single d-galactosyl unit side-chain. About half of the mannose residues were O-acetylated at C-2 and C-3 in 1.7:1 mole proportion.

  • galactoglucomannan from the secondary cell wall of Picea Abies l karst
    Carbohydrate Research, 2000
    Co-Authors: Peter Capek, Marta Kubackova, Juraj Alfoldi, Ladislav Bilisics, Desana Lišková, D. Kákoniová
    Abstract:

    Abstract The fine structural features of alkali-extracted galactoglucomannan composed of d -galactose, d -glucose and d -mannose in a 1:8:33 mol proportion from the secondary cell walls of Picea Abies L. Karst have been determined. Compositional and methylation analyses of the polymer, partial acid hydrolysis, as well as 1 H and 13 C NMR measurements of the polymer and products of partial acid hydrolysis confirmed a β-(1→4)-linked backbone of galactoglucomannan containing the segments of mannosyl residues (Man 2 , Man 3 , Man 4 , etc.) interrupted with the segments having both mannose and glucose residues, as well as the segments in which d -Glc p units can be adjacent to each other (Glc 2 ). Further, the low content of branching points (∼3%) at the positions of O-6, O-3 and O-2 of mannosyl and O-6 and O-3 of glucosyl residues, but preferably of mannosyl ones, indicates the presence of short side-chains terminated at position O-6 predominantly by d -galactose units as single stubs.

  • Galactoglucomannan from the secondary cell wall of Picea Abies L. Karst.
    Carbohydrate research, 2000
    Co-Authors: Peter Capek, Marta Kubackova, Juraj Alfoldi, Ladislav Bilisics, Desana Lišková, D. Kákoniová
    Abstract:

    The fine structural features of alkali-extracted galactoglucomannan composed of D-galactose, D-glucose and D-mannose in a 1:8:33 mole proportion from the secondary cell walls of Picea Abies L. Karst have been determined. Compositional and methylation analyses of the polymer, partial acid hydrolysis, as well as 1H and 13C NMR measurements of the polymer and products of partial acid hydrolysis confirmed a beta-(1-->4)-linked backbone of galactoglucomannan containing the segments of mannosyl residues (Man2, Man3, Man4, etc.) interrupted with the segments having both mannose and glucose residues, as well as the segments in which D-Glcp units can be adjacent to each other (Glc2). Further, the low content of branching points (approximately 3%) at the positions of 0-6, 0-3 and 0-2 of mannosyl and 0-6 and 0-3 of glucosyl residues, but preferably of mannosyl ones, indicates the presence of short side-chains terminated at position 0-6 predominantly by D-galactose units as single stubs.