Top
ヘッダー

(Upload on May 8 2015) [ 日本語 | English ]

Wood ()






Mount Usu / Sarobetsu post-mined peatland
From left: Crater basin in 1986 and 2006. Cottongrass / Daylily

[ wood physics | wood chemistry | forest science | tree ]

Wood:
the secondary xylem in the stems of trees (s.s.)
the secondary xylem and the same type of tissue elsewhere such as in the roots of trees or shrubs (s.l.)
索引

Wood physics (木材物理)


The area of wood science concerned with the physical and mechanical properties of wood and the factors which affect them.

Wood density (材密度)

= wood specific gravity
= the dry weight per unit volume of wood

specific gravity = oven dry weight/fresh volume
water content = (wet weight - dry weight)/fresh volume

using in allometric equations estimating tree biomass and carbon stocks from stem diameters
indicating fire tolerance

The heaviest wood density is reported from Krugiodendron ferreum (black ironwood) of which density is 1.3 g/cm³ → sinking

Table. Representative wood densities (as a guide). The density is fluctuated due to location, water content, part, etc. -: not determined.
Species = Wood density (g/cm³)
Abies sachalinensis (トドマツ) = 0.42
Acer amoenum (オオモミジ) = -
Acer japonicum (ハウチワカエデ) = -
Acer mono (エゾイタヤ) = 0.67
Acer negundo (ネグンドカエデ) = -
Betula platyphylla (シラカンバ) = 0.64
Castanea crenata (クリ) = 0.60
Cercidiphyllum japonicum (カツラ) = 0.45
Ginkgo biloba (イチョウ) = 0.55
Picea jezoensis (キハダ) = 0.45
Picea jezoensis (エゾマツ) = 0.48
Pinus nigra (オウシュウクロマツ) = 0.48
Populus nigra (セイヨウハコヤナギ / ポプラ) = 0.45
Prunus sargentii (エゾヤマザクラ) = 0.63
Quercus mongolica (ミズナラ) = 0.68
Quercus rubra (アカナラ) = 0.54
Robinia pseudoacacia (ニセアカシア) = 0.75
Sorbus commixta (ナナカマド) = 0.71
Taxus cuspidata (イチイ) = 0.48
Tilia japonica (シナノキ) = 0.44
Tilia maximowicziana (オオバボダイジュ) = 0.43
Ulmus davidiana (ハルニレ) = 0.59
The table is used for estimating CO2 fixing in trees in a field trip, Nature in the eco-campus of Hokkaido Universit (北大エコキャンパスの自然)
Table 1. Comparison of lowland forests in number of tree species, mean of specific gravity per forest and mean of the standard deviation (SD) of specific gravity per forest in the three regions. n = number of samples (Williamson 1989)
  Forest type and location  n  Mean species  Specific gravity
                               richness      Mean  SD

  Indiana (temperate)
    Beach-maple             15   19.2        0.53  0.08
    Mixed woods              5   20.2        0.53  0.09
    Oak-hickory              3   17.7        0.53  0.09
    Lowland depression       7   23.0        0.53  0.08
  Costa Rica (tropical)
    Tropical dry             1   90          0.53  0.20
    Tropical moist           2  114          0.50  0.14
    Tropical wet             2  149          0.48  0.16
  Trinidad
    Deciduous seasonal       2   55          0.58  0.17
    Semi-evergreen seasonal  5   60          0.59  0.17
    Evergreen seasonal       6   93          0.58  0.18

gravity
Fig. Specific gravity as a function of distance from pith
for Ceiba pentandra from a tropical dry forest and a tropical
wet forest.

Wood processing (木材加工)


Wood tissue

Wood chemistry (木材化学)


[analytical chemistry (分析化学), cell wall(細胞壁)]

The area of wood science focusing on the chemical and biochemical aspects of trees and products such as pulp and paper that are derived from trees

Cellulose (セルロース)

The major component of trees → more than 50% of wood (or woody part) for broad-leaved and needle-leaved trees are cellulose

Role (in a metaphorical sense): wood = ferroconcrete ⇔ cellulose = rebar

cellulose

Hemicellulose (ヘミセルロース)

Lignin (リグニン)

Broad-leaved tree: 20-25%
Needle-leaved tree: 28-31%

lignin
Basic unit: phenylpropane-typed (C6-C3) carbon skeleton
→ different structural components between species

needle-leaved tree: guaiacylpropane (グワヤシルプロパン)
borad-leaved tree: syringylpropane (シリンギルプロパン)
babmoo and dwarf bamboo: condensation product of guaiacylpropane, syringylpropaneand p-hydroxyphenylpropane (p-ヒドロキシフェニルプロパン)

フッター