Variation Within Trees of Wood Anatomical Properties in Chinese-Fir Plantation and Their Relationship Modeling Equations

A comprehensive analysis on the variation pattern of early- and latewood tracheid morphological parameters along tree (Cunninghamia lanceolata Hook.) height, including length and width, wall thickness, tissue proportion, cell wall percentage, width of growth rings, and on the relationship among them are conducted. The results indicate an initially rapid and then gentle increase of tracheid length and width, thickness of the radial wall and tangential wall of tracheid, area percentage of tracheid from pith to outward, while S2 microfibril angle (Mfa) of tracheid, and rays percentage gradually decrease and then tend to be stable. The variation of all anatomical parameters but earlywood cell wall thickness shows no significance along tree height. The radial variation pattern of width of growth rings is characterized with initially slight decrease followed immediately by a rapid and then much more gentle increase from pith to outward. The delimitation age between juvenile and mature wood is 14-16 years. Com     

日本落叶松无性系木材性质的遗传变异

对10个10年生日本落叶松无性系的木材基本密度、管胞参数进行了测定.结果表明:木材基本密度,早、晚材管胞宽度和早材长宽比无性系间差异显著;木材基本密度,早、晚材管胞长度,早晚材管胞宽度和早晚材长宽比径向变异模式相似,即从髓心向外以曲线形式不断增加,有时亦有起伏;早材从髓心向外以近似直线的形式缓慢增加,晚材从髓心向外以曲线形式增加,初期增加幅度较大,到一定年龄后趋于水平变化并略有波动;材质性状与树木年轮间的关系以对数方程、幂函数方程、指数方程拟合效果较好;除了晚材壁腔比和早材壁厚外,其它木材性质的重复力均在0.5以上,受中度或中度以上的遗传制约,按照20%的选择率,长宽比和晚材管胞长能获得较高的遗传增益.     

Relationships among selected wood properties of 20-year-old Taiwania (<Emphasis Type="Italic">Taiwania cryptomerioides</Emphasis>) trees

The relationships between bending properties, compressive strength, tracheid length, microfibril angle, and ring characteristics of 20-year-old Taiwania (Taiwania cryptomerioides Hay.) trees were examined. The trees came from different thinning and pruning treatments, but the practices showed no significant effect on the investigated properties. The results showed that based on comparison with the literature, plantation-grown immature Taiwania have noticeably lower average strength properties than mature trees of the same species. Wood density and bending and compressive strengths were not related to either tracheid length or microfibril angle in young Taiwania. There were positive relationships between bending strength and compressive strength. The wood density, ring width, earlywood width, earlywood density, and latewood percentage were the most important predictors of strength by simple linear regressions. The wood density and ring width/earlywood width may be considered as indicators for assessing the bending strength, while wood density and latewood percentage were the best predictors of compressive strength by multiple linear regressions.     

Genetic control of intra-ring wood density variation in hybrid larch (Larix gmelinii var. japonica × L. kaempferi) F1

Genetic parameters for various wood density traits were estimated in 29-year-old trees of 18 full-sib families of hybrid larch (Larix gmelinii var. japonica × Larix kaempferi) F₁. Intra-ring density variation (IDV) was also evaluated using a model that expresses the pattern curve from earlywood to latewood as a power function. A high IDV indicates an abrupt change in wood density from earlywood to latewood. The ring width and wood density traits of individual rings were determined by X-ray densitometry. Overall wood density (RD) was shown to increase with increasing ring number, ranging from 0.42–0.59 g/cm³, whereas IDV of individual rings decreased gradually from pith outwards. Estimates of individual tree narrow-sense heritability of RD and IDV were 0.66 and 0.67, respectively. IDV showed negative genetic and phenotypic correlations with RD (r _g = −0.99, r _p = −0.72). The predicted genetic gains in latewood proportion and IDV were higher than that of RD. These results suggest that the intra-ring density variation is under moderate genetic control equivalent to wood density. The trend of increasing wood density from earlywood to latewood was associated with changes in both tracheid diameter and cell wall thickness.     

Effects of radial growth rate on selected indices for juvenile and mature wood of the Japanese larch

To examine the differences between juvenile and mature wood, 12 aged sample trees from two areas of Nagano Prefecture were harvested; and the radial development of tracheid length, the ring density, and the relation of the radial growth rate (observed by ring width) with some selected indices of ring structure were investigated. The results proved that the radial variation of tracheid length with ring number can be described by a logarithmic formula, and both plantations reached the demarcation of juvenile and mature wood at age 18. With the segmented regression method, we also analyzed radial variation of mean density and found that the demarcation of juvenile and mature wood was at age 15 for sample trees from Saku and at age 21 for those from Yabuhara. By using the results of estimates from juvenile and mature wood based on ring density, we found that high growth rates resulted when producing lower-density wood during the juvenile period, but these rates did not occur during the mature period. The basic reason for this phenomenon is the variation in patterns of earlywood and latewood in juvenile and mature wood, respectively. This result advised us that when managing plantations of Japanese larch it is necessary to take different measurements at different growth periods.     

The effect of axial strain on crystalline cellulose in Norway spruce

The effect of strain on dry, clear Norway spruce (Picea abies [L.] Karst.) wood was studied by tensile testing along the cell axis and by in situ X-ray diffraction measurements. The mean microfibril angle (MFA) was initially 3–12 degrees and did not decrease due to strain. Based on the positions of the reflections 200 and 004 of crystalline cellulose, cellulose chains elongated and the distance between the hydrogen bonded sheets of chains decreased due to the strain. The elongation of the unit cell parallel to the cellulose chains was twice as high in juvenile wood as in mature wood. The (X-ray) Poisson ratio ν _ca for crystalline cellulose in Norway spruce was calculated from the deformation of the unit cell. The average ν _ca of earlywood was 0.28 ± 0.10 in juvenile wood and 0.38 ± 0.23 in mature wood. In latewood, the average ν _ca was 0.48 ± 0.10 in juvenile wood and 0.82 ± 0.11 in mature wood. The average ν _ca values were not directly correlated to the crystallite dimensions or to the mean MFA in juvenile and mature earlywood and latewood. The results show that the amorphous matrix has a definite effect on the deformation of cellulose crystallites.     

Relationships of climate and cell features in stems and roots of black spruce and balsam fir

? The anatomical differences of mature black spruces and balsam firs were examined at stem and root level in order to characterize their wood properties at cellular level and link these differences to climate.

? Anatomical variability of these species was evaluated in relation to climate data gathered from 2001 to 2004 during the cell enlargement (CE) and wall thickening and lignification (WTL) phases. Lumen area, single cell wall thickness and total tracheid radial diameter were analyzed and regrouped into earlywood and latewood.

? Results from a principal component analysis (PCA) indicated that both first eigenvectors account for 82% and 90% of total variance for CE and WTL respectively. These component factors revealed that precipitation, humidity and number of days with precipitation significantly influence the lumen area (p = 0.0168) and radial cell diameter (p = 0.0222) in earlywood. Significant differences were registered between species and tree parts (stem and root) for the lumen area, radial cell diameter and cell wall thickness in both earlywood and latewood.

? In our study, black spruce exhibited smaller tracheid size in both stem and roots compared to balsam fir. Furthermore, the lower amount of tracheids produced during the growing season and higher proportion of latewood ensure a higher wood density of black spruce. The influence of temperature on earlywood formation is significant, whereas no influence was observed on latewood.

     

油松株内幼龄材与成熟材材性的比较研究

本文就中条山油松株内幼龄材与成熟材材性差异的比较研究,讨论对幼龄期划分的依据。根据木材解剖特征、物理力学性质的径向变异规律,确定其幼龄期为14年。随着树干高度的增加,油松木材幼龄期逐渐缩短、株内幼龄材范围及所占断面上的比例变小。株内幼龄材与成熟材材性差异显著。幼龄材管胞长度短、直径小,胞壁薄,微纤丝角度大,生长轮较宽,晚材率低,浸提物含量高,基本密度较大。幼龄材的力学强度远远小于成熟材。     

Hydraulic and mechanical properties of young Norway spruce clones related to growth and wood structure

Stem segments of eight five-year-old Norway spruce (Picea abies (L.) Karst.) clones differing in growth characteristics were tested for maximum specific hydraulic conductivity (k(s100)), vulnerability to cavitation and behavior under mechanical stress. The vulnerability of the clones to cavitation was assessed by measuring the applied air pressure required to cause 12 and 50% loss of conductivity (Psi(12), Psi(50)) and the percent loss of conductivity at 4 MPa applied air pressure (PLC(4MPa)). The bending strength and stiffness and the axial compression strength and stiffness of the same stem segments were measured to characterize wood mechanical properties. Growth ring width, wood density, latewood percentage, lumen diameter, cell wall thickness, tracheid length and pit dimensions of earlywood cells, spiral grain and microfibril angles were examined to identify structure-function relationships. High k(s100) was strongly and positively related to spiral grain angle, which corresponded positively to tracheid length and pit dimensions. Spiral grain may reduce flow resistance of the bordered pits of the first earlywood tracheids, which are characterized by rounded tips and an equal distribution of pits along the entire length. Wood density was unrelated to hydraulic vulnerability parameters. Traits associated with higher hydraulic vulnerability were long tracheids, high latewood percentage and thick earlywood cell walls. The positive relationship between earlywood cell wall thickness and vulnerability to cavitation suggest that air seeding through the margo of bordered pits may occur in earlywood. There was a positive phenotypic and genotypic relationship between k(s100) and PLC(4MPa), and both parameters were positively related to tree growth rate. Variability in mechanical properties depended mostly on wood density, but also on the amount of compression wood. Accordingly, hydraulic conductivity and mechanical strength or stiffness showed no tradeoff.     

Variation in density of Picea sitchensis in relation to within-tree trends in tracheid diameter and wall thickness

The influences of cambial age and ring width on density of Sitkaspruce (Picea sitchensis (Bong.) Carr) were analysed in relationto within-tree trends in tracheid diameter and cell wall thickness.Discs were sampled at breast height from a total of 24 trees,from seven stands at three contrasting sites in Wales, and atbreast height, 30 per cent and 60 per cent total tree heightfrom one of the stands. Across the juvenile wood, ring density decreased with ring numberfrom the pith while radial tracheid diameter increased. Theseoverall trends were considered to be inherent to tree growth,presumably associated with cambial ageing, since they occurredin all trees on all sites. In juvenile wood, density also variedwith site growth rate (as indicated by ring width) at similarcambial age, wider rings being associated with more rapidrateof change in tracheid diameter with ring number and with decreasein tracheid wall thickness. Consequently, on a site having treeswith high growth rate density decreased more rapidly acrossthe juvenile wood, down to a lower minimum value, than on siteswith a slower growth rate. In mature wood, the decrease in densitywith increase in ring width was associated with differencesin both tracheid diameter and wall thickness. Density was slightly(though not significantly) higher at breast height than in comparablerings at 30 per cent total height, associated with significantlythicker tracheid walls at breast height. Changes in radial tracheid diameter (with ring number, or withring width) were associated with greater differences in theearlywood than towards the latewood end of each growth ring,while variations in wall thickness with ring width were associatedwith rate of increase in wall thickness towards the latewoodend. This may account for some previously conflicting reportson influence of silvicultural management on density, for densityis likely to vary with influence of environment on the seasonalcycle of cambial activity. The extent of the juvenile wood as delimited by the inner coreof wide growth rings does not necessarily correspond to theregion of varying tracheid dimensions in Sitka spruce.     

马尾松人工林管胞长度的株间和株内变异

林木株间变异和株内变异是木材的两个主要变异来源,由于木材性状具有较强的遗传性以及育林措施对木材的可塑性,人们可以培育出材质优异的木材,然而因变异的存在,在如何充分利用木材时却遇到了许多困难。林学家的一个主要目的就是在充分掌握木材变异规律的基础上,采用有效方法提高材质的均匀性。     

Genetic parameters of growth and wood quality traits in Picea abies

Genetic parameters were estimated for wood and growth traits in two 19-yr-old clonal trials and a 40-yr-old full-sib progeny trial of Norway spruce [Picea abies (L.) Karst.]. In the clonal trials high (>0.4) broad-sense heritabilities were found for wood density traits, lignin content, number of internal cracks, growth traits, spiral grain and number of resin canals. Moderate (0.2–0.4) heritabilities were found for tracheid lumen diameter and cell wall thickness, microfibril angle and tracheid length, while low heritabilities (<0.2) were found for pulp yield, fibre strength, wood stiffness and wood colour. Lignin content and pulp yield showed low genetic variation, whereas the genotypic coefficient of variation for most other traits ranged between 5 and 15%. Most traits showed low levels of genotype by environment interaction. Among the wood properties, latewood proportion, earlywood density and ring density showed significant, adverse correlations with volume in both clonal trials.     

Statics and kinetics of water vapor sorption of small loblolly pine samples

A better understanding of the sorption behavior of different wood structures could be useful in protecting wood against wood deterioration and fungal attack. The purpose of this study was to investigate the effect of differences among earlywood, latewood, and tree ring location within the stem cross-section of loblolly pine (Pinus taeda) on the sorption kinetics and statics of water vapor under ambient conditions. The water vapor sorption of earlywood and latewood in different tree rings was recorded using a dynamic contact angle analyzer under relative humidity changes from 11 to 89%, as provided by saturated salt solutions. Earlywood had higher sorption rates and diffusion coefficients than latewood, while outer tree rings had higher sorption rates and diffusion coefficients than inner tree rings. The sorption isotherms of earlywood, latewood, and different tree ring locations within the stem cross-section were fitted very well by a Hailwood–Horrobin model.     

Variability of selected wood characteristics in 40 half-sib families of black spruce (Picea mariana)

Summary Based on 15-year-old black spruce (Picea mariana) trees from 40 half-sib families sampled from 9 blocks of a family test in New Brunswick, this study examined intertree and intratree variation in various wood density and ring width characteristics. Of various variance components of the intertree variation, a remarkable variance component due to family was found in wood density characteristics (viz. average wood density, average earlywood density and latewood density of the tree), and these characteristics are thus under strong genetic control (h _i ² ranging from 0.60 to 0.86, and h _f ² from 0.56 to 0.68). It, to a lesser extent, applies to ring width characteristics at the tree level (viz. average ring width, and average earlywood width, latewood width and latewood percent of the tree) that show a lower heritability (h? from 0.18 to 0.28, and h _f ² from 0.22 to 0.36). Both block and block × family interaction contribute little to the total intertree variation encountered in 40 families from 9 blocks, while tree-to-tree variation within the family accounts for most (over 3/4) of the total intertree variation.Compared to the intertree variation (tree-to-tree variation within the family), the intratree variation in various wood characteristics studied is considerably larger in this species. It appears that most intraring wood density characteristics show a relatively smaller intertree variation but a relatively larger intratree variation as compared to ring width characteristics (except latewood width and latewood percent). Latewood width and latewood percent show the smallest intertree variation and the largest intratree variation. Between the two sources of the radial intratree variation, cambial age explains much more variation in most intraring wood density characteristics, while ring width accounts for more variation in earlywood width, latewood width and intraring density variation. This indicates that wood density of growth rings in this species is dependent more on cambial age than ring width (growth rate). Among various wood density and ring width characteristics studies, maximum (latewood) density shows the strongest response to calendar year. This characteristics is thus a useful dendroclimatic parameter in this species.I would like to thank Dr. E.K. Morgenstern and Mr. D. Simpson for their involvement in the planning of this study. Thanks are also due to G. Chauret, T. Keenam, R. Ploure, V. Steel and C. Reitlingshoefer for their technical assistance     

马尾松木材性状的遗传变异及其在造纸工业中的应用

综述了马尾松木材比重，管胞长度、晚材率及它们的过渡年龄、浆纸性能等在种源、林分、林分内个体及株内的遗传变异，并对马尾松材性改良前景作了讨论。     

Intra-increment circumferential variation in tracheid length as a basis for sampling genetically superior trees of deodar (Cedrus deodara (Roxb.) Loud.)

Summary Intra-increment circumferential variation in tracheid length at breast-height in deodar (Cedrus deodara (Roxb.) Loud. vern. diar) has been studied with the main objective of evolving an efficient sampling procedure for the purpose of comparing tracheid length amongst individual trees of forest stands. It has been studied in five sampling strata namely: whole-annual ring, whole-earlywood, whole-latewood, first-firmed earlywood and last-formed latewood. Tracheid length shows significant circumferential variation in whole-annual ring, whole-earlywood, whole-latewood and last-formed latewood. However, when the mean tracheid length of two opposite directions is compared with the mean tracheid length of eight cardinal directions in these sampling strata, then no significant difference is observed. First-formed stratum of an annual ring exhibits statistically consistent values around the circumference and thus sampling from any random radial direction can serve the purpose for the comparison of inherent values of tracheid length amongst the deodar trees.The financial assistance given by Himachal Pradesh University as H.P.U. Junior Research Fellowship to second author is highly acknowledged     

人工兴安落叶松次生木质部的解剖学研究

运用木材解剖图像分析系统和显微照相的方法对人工兴安落叶松次生木质部的解剖结构进行研究,结果表明:落叶松具正常树脂道和受伤树脂道两种类型,前者常见于晚材。落叶松生长轮内的早晚材在干和枝内急变,在根内缓变。早材管胞呈六边形至多边形,胞壁常见单列具缘纹孔,偶见对列具缘纹孔;晚材管胞多呈矩形,胞壁鲜见具缘纹孔,通常为单列具缘纹孔。落叶松木射线同时具有单列木射线和纺锤形木射线两种类型,纺锤形木射线中仅含一枚纵行树脂道。纵行管胞与木射线交叉形成的纹孔场为云杉型。从根到干再到枝,管胞逐渐细化,管胞长度逐渐减小,木射线分布由密到疏。     

Quantitative analysis of lignin using an UV microscopic image analyser. variation within one growth increment

Summary The variation of the lignin content within one growth increment of Abies sachalinensis was investigated with the aid of an ultraviolet microscopic image analyser. The lignin content was determined continuously in each cell within a growth increment. The direct photometric scanning method of UV image is believed to give accurate results for determination of the lignin content of the cell wall, since it contains fewer assumptions. The lignin content of the earlywood was higher than that of latewood in adult wood as same as the others. It was high, however, in the terminal zone of the latewood. The trends of the juvenile wood were quite different from those of the adult wood. The lignin content increased from earlywood to latewood.This paper was presented at the Wood Anatomy Congress of IAWA, Aug. 27, 1979, Amsterdam. The authors wish to express their gratitude to Prof. Dr. J. Bauch for helpful advice     

The effects of drying on the structure and permeability of the wood of Abies grandis

Summary The effects of air-drying and solvent-drying on the sapwood of Abies grandis have been investigated by a new method for the determination of the size and number of conducting tracheid lumina and pit membrane pores which involves the measurement of gaseous permeability at various mean pressures. Both earlywood and latewood tracheids (83% of the total) were found to be conducting in solvent-dried wood, but in air-dried wood only latewood tracheids (32% of the total) were conducting. In solvent-dried wood there were on average 27,000 pit membrane pores per conducting tracheid compared with only 600 in air-dried wood. In both, the average pit membrane pore radius was about 0.1 m.Liquid permeabilities have been predicted from the calculated radii and numbers. The liquid permeability of solvent-dried wood was 31 times greater than that of air-dried wood in which the lumina were responsible for 13% of the total resistance to flow. The lumina were responsible for 39% of the resistance in solvent-dried wood and it is suggested that in first-formed earlywood the lumina may cause more than half the total resistance.A new method is described for the cleaning of direct carbon replicas of wood. In this the cellulose is removed by cellulase instead of sulphuric acid, and no wax backing is required. This provides much cleaner replicas. Electron micrographs have been obtained of both earlywood and latewood dried by the two methods.The authors wish to thank Mr. A. R. Sayers for preparing the computer programme used in this work, Dr. R. Ph. C. Johnson for his help and advice regarding the electron microscopy and Professors Matthews and Weatherley for their advice and encouragement.