北京地区I-214杨树木材解剖特性与基本密度的株内变异及其预测模型

对北京地区Ⅰ—214杨的纤维和导管分子长及宽度、纤维壁厚、组织比量、胞壁率与基本密度和生长轮宽度在株内不同高度上的变异模式及其之间的相关关系进行了全面的测定与分析。结果表明：纤维长、宽及壁厚，导管分子长、弦径和导管比量径向变异由髓心向外迅速递增，而后趋于平缓；而导管个数、纤维与射线比量、胞壁率的径向变异由髓心向外逐渐递减，再趋于稳定。不同高度间的解剖参数(胞壁率除外)差异不显著。基本密度的径向变化是髓心处较大，往外先略减而后快速递增，然后趋于平缓。木材幼龄期为10～12a，幼龄材比成熟材的基本密度低，纤维和导管分子均短与窄、壁薄，纤维和射线比量大、导管个数多、导管比量小，生长轮宽度窄，且两者间的基本密度、纤维和导管分子长度、导管弦径、导管和射线比量差异均达显著水平。生长速度对解剖性质影响不显著，但与木材基本密度呈显著负相关，解剖参数与基本密度关系密切。基本密度和各项解剖参数均与生长轮年龄为极显著相关，可建立模型预测。     

施肥对中龄马尾松木材主要物理性质和管胞形态的影响

采用正交设计方差分析方法,研究了施肥对中龄马尾松木材主要物理性质和管胞形态的影响.结果表明施肥有助于增加生长轮宽度,提高晚材率,但经正交设计方差分析差异不显著.P肥使管胞宽度、腔径,尤其是径向腔径有所增加,但各处理间差异不显著.因此,可以认为施肥对管胞形态影响不大.施肥对木材基本密度的影响较复杂,似乎与肥料种类、施肥量,甚至与树干部位有关,P肥使下部木材基本密度显著增加,N、K肥对木材基本密度影响不大.     

栽植密度对小黑杨人工林木材解剖特性的影响

以山西朔州地区的小黑杨人工林为研究材料,研究不同栽植密度(1 000、500、250株·hm-2)对小黑杨木材解剖特性的影响.结果表明:栽植密度对纤维宽度、双壁厚、导管比量、胞壁率、导管个数、导管弦向直径的影响达极显著水平;对壁腔比的影响达显著水平;对纤维长度、长宽比、纤维比量、射线比量虽有一定的影响,但不显著.栽植密度与纤维宽度、导管直径呈负相关关系,与导管个数和比量呈正的相关关系.栽植密度对纤维形态的径向变异有不同程度的影响,但不改变纤维形态变异的一般规律.纤维长度的径向变异为从髓心至树皮向外逐渐增加,到第12 轮达到最大值后略有下降,纤维宽度、长宽比、双壁厚、腔径的径向变异类似于纤维长度;壁腔比的总体径向变异为沿髓心向外,呈先升后降的波动性变异趋势.     

人工林杉木管胞形态与基本密度径向变异规律研究

对浙江省开化县遗传改良无性系杉木(Cuninghamia lanceolata)"F24x那1-1"的管胞形态特征及径向变异规律进行研究。结果表明:管胞处于幼龄期时,管胞长度、管胞长宽比在髓心附近较小,随着生长轮龄的增加,指标值呈明显的增大趋势,在第13年轮时增至最大值,之后趋于稳定或略有降低;管胞宽度、管胞双壁厚及管胞壁腔比径向变异规律一致,随着生长轮龄的增加,指标值先增至最大值,之后趋于平缓或略有降低,变异幅度较小;杉木基本密度径向变异规律与管胞长度变异规律基本一致,基本密度在第2年最小,为0.283 g/cm3,随着树龄增加,基本密度逐渐增大,第13年时达到最大值,为0.348 g/cm3。研究结论可为木材精准加工利用及遗传改良木材育种提供理论支持。     

Ⅰ-69杨年轮宽度和密度变异规律

以Ⅰ-69杨木材为试样,运用树木年轮图像分析系统和树木年轮分析系统获取年轮宽度和年轮密度数据,并对组成成分径向变异和轴向变异规律进行了分析。结果表明:Ⅰ-69杨木材密度的径向变异规律随树龄增加而增大,最大密度波动较大,最小密度随树龄增加总体趋势下降,早材密度、晚材密度随树龄增加而增加;年轮组成成分各项指标株内径向变异极显著,株间径向变异不显著。年轮密度各组成成分随高度增加而增加,其中年轮平均密度、早材密度、最小密度增加量较小,年轮最大密度、晚材密度增加量较大;相对而言,Ⅰ-69杨木材密度径向变异大于轴向变异。     

毛白杨枝条木质部细胞分化的动态变化及其与形成层活动的相互关系

应用定量解剖学和显微图像分析技术 ,得到了毛白杨枝条形成层细胞与其衍生木质部细胞解剖特征在形成层活动期内的变化情况 ,并探讨了两者之间的关系。采用X射线微密度测定技术 ,了解了同一生长轮内木材密度沿径向方向上的变异 ,讨论了其与木质部细胞解剖特征之间的关系。结果表明 ,形成层纺锤形细胞的径向和弦向宽度在活动期不同阶段差异不显著 ,而纤维长度、纤维宽度、壁腔比、微纤丝角、导管分布频率和胞壁率差异极显著 ;导管组织比量差异显著 ;导管分子长度、纤维比量和射线比量差异不显著。同一生长轮内木材密度的径向变异与活动期不同阶段形成的木质部细胞数量及其解剖特征直接相关。形成层带细胞层数与纤维长度、纤维长宽比和壁腔比呈极显著负相关 ,与纤维宽度呈显著正相关 ;形成层纺锤形细胞的径向宽度与纤维长度、纤维长宽比和射线比量呈显著负相关 ;形成层纺锤形细胞的弦向宽度与纤维宽度呈显著正相关。总体看来 ,在整个形成层活动期 ,形成层纺锤形细胞与木纤维的解剖特征之间随时间变化的相关性较好 ,而与导管分子的相关关系则不明显     

马尾松年轮宽度和木材基本密度的种源变异及早期选择

针对浙江省淳安县姥山林场的24年生49个产地马尾松种源试验林,采集植株胸高处木芯,分析种源年轮宽度和木材基本密度的年龄效应。结果表明:除近髓部1～5轮年轮段的木材基本密度外,其他年龄段的年轮宽度和木材基本密度皆存在显著的种源差异,进一步说明通过种源选择可实现木材生产力和木材基本密度的遗传改良。不同年轮段木材基本密度的种源变异相对稳定,而年轮宽度的种源变异则易受环境的影响,幼龄材年轮宽度的种源变异较小,仅为成熟材的63.29%。来自不同种源区的种源年轮宽度的径向变异规律相似,皆表现出先增后减的变化趋势,在6～10轮达到最大值;年轮木材基本密度径向变化规律则与年轮宽度不同,表现为随年龄增长先增加后逐渐稳定的S型变化趋势,并据此筛选出广西横县、恭城、忻城,广东乳源和福建南靖5个木材基本密度径向均匀性高的纸浆材优良种源。不同年轮段年轮宽度和木材基本密度的相关分析显示,约在8年生选择径向生长快的种源会明显地降低其木材基本密度。基于性状早晚相关分析,认为可在7年生时先淘汰生长较差的种源,在12年生再开展种源生长和木材基本密度的联合选择。     

琼楠人工林木材纤维形态径向变异研究

以琼楠木材为研究对象,通过纤维形态分析仪和显微镜对琼楠木材纤维形态进行测定及分析,研究其径向变异规律。结果表明,琼楠木材的纤维长度、宽度、内径、双壁厚平均值分别为1 034.75、19.95、11.02、9.03 μm,长宽比、壁腔比平均值分别为51.87、0.82,各指标在生长轮径向方向的变化规律具有一定的相似性,均表现为沿髓心向外的生长轮年龄增加而逐渐增大,变化十分显著;琼楠木材纤维的内径受径向上生长轮年龄的影响不显著。以期为琼楠木材的应用以及种植培育提供理论依据。     

邓恩桉生材含水率、年轮宽度及木材密度研究

为了解邓恩桉的木材性质,本研究采用排水法和《GB/T 1930-2009》方法测定邓恩桉的生材含水率、年轮宽度以及木材密度。结果表明：全树生材含水率、年轮宽度、生材密度和基本密度均值分别为114.61%、4.73 mm、1.164 g·cm-3、0.522 g·cm-3。随着树高的增加,年轮宽度、木材密度呈-大-小-大‖趋势,生材含水率呈-小-大-小‖趋势;由髓心向外,木材密度逐渐减小,生材含水率逐渐增大,年轮宽度先增加后减小。4个材性指标在树干径向不同位置间差异极显著,在不同树高间差异不显著（除年轮宽度外）。基本密度与3个材性指标间存在极显著或显著相关。     

人工幼龄印度黄檀木材解剖性质和结晶度的径向变异及预测模型

对元江地区幼龄印度黄檀木材各生长轮间的解剖各参数和结晶度的径向变异趋势及它们的相关性做了全面的测定和分析,结果表明:纤维长度和宽度、导管分子长度和弦径、纤维比量总体径向变化趋势是从髓心往外呈增加趋势;纤维壁厚和生长轮的径向变异趋势是先增加后减小;导管比量、胞壁率和微纤丝角的变化趋势是沿髓心向外呈递减趋势;结晶度的径向变异趋势是先增加后减小.方差分析表明:各生长轮间的解剖参数和结晶度差异均明显.相关分析表明:生长轮年龄与各解剖参数和结晶度相关性显著,据此建立了木材解剖性质和结晶度预测模型,相关系数大都达到0.88以上.     

Pilot Study to Examine Radial Variation in Annual Ring Width, Density and Shrinkage

The annual ring width, density and shrinkage variation from pith to bark in Chinese fir (Cunninghamia lanceolata) and Boka sugi (Cryptomeria japonicd) were studied and compared. The results show that the ring width decreased sharply from pith to bark for Chinese fir. However, the ring width variation pattern for Boka sugi followed a different way, i.e., the ring width decreased to the fifth ring, increased to the tenth ring, decreased again to the fifteenth, and then increased to the twentieth, where it became constant. The large variations of Boka sugi appeared to show the maintenance of fast growth for many years. The annual ring mean density of Chinese fir increased gradually from pith to bark. However, the density changes for Boka sugi indicated the opposite trend, i.e., the mean density decreased gradually from pith to bark. The former showed a pattern as the same as a pine and a larch, and the latter was often found in a cedar and a cypress. The longitudinal shrinkage in juvenile wood was much hig     

Radial variation in partial compression properties perpendicular to the grain of Japanese larch (Larix kaempferi)

This study investigated the densities, average width of annual rings, and partial compression stresses at 5 % strain perpendicular to the grain of air-dried wood specimens, which were continuous in the radial direction from the pith and were obtained from Japanese larch (Larix kaempferi) trees with different diameters at breast height in the same stand, to evaluate the radial variations in partial compression properties perpendicular to the grain. The air-dried densities of the wood increased with the distance from the pith. The average width of annual rings of the wood tended to decrease with increasing distance from the pith and those of medium- and large-diameter trees seemed to increase near the pith. The partial compression stresses at 5 % strain in the tangential loading direction tended to increase with the distance from the pith and with air-dried wood density. However, in the radial loading direction, this tendency was not observed. The partial compression stresses at 5 % strain in the radial loading direction tended to be low in wood with a small average width of annual rings. These results indicate that the factors affecting the radial variations in the partial compression stress at 5 % strain differ depending on the loading directions.     

Wood properties and their among-family variations in 10 open-pollinated families of Picea jezoensis

This study aimed to evaluate radial and among-family variations of wood properties in Picea jezoensis. A total of 174 trees were randomly selected from 10 open-pollinated families in a progeny trial for measuring stem diameter, dynamic Young’s modulus of log (DMOE_log), annual ring width (ARW), air-dry density (AD), modulus of elasticity (MOE), and modulus of rupture (MOR). Mean values of DMOE_log, AD, MOE, and MOR were 9.60 GPa, 0.41 g/cm³, 9.44 GPa, and 76.6 MPa, respectively. Significant differences among families were observed in all properties. F values obtained by analyzing variance in wood properties were higher than those generally observed in growth traits. In addition, F values in wood properties remained relatively higher from the 1st to 25th annual ring from the pith, although F value in ARW rapidly decreased with each increase in annual ring number. These results indicate that genetic factors largely contributed to the variance in wood properties compared with the growth traits.     

Determination of fiber length and juvenile and mature wood zones in Acer velutinum Boiss. trees grown in Iran

In our investigation we studied fiber lengths and the transition age from juvenile to mature wood in Acer velutinum Boiss. For this purpose, samples from three normal maple trees at a Noshahr site in northern Iran were selected. Disks were cut at breast height. Test samples were taken along a radial direction from the pith to the bark, accounting for every ring during a 48-year period. We used the Franklin method to distinguish between fibers of juvenile and mature wood. The results show that the fiber length increased along the radial direction from the pith to the bark. The transition age between juvenile and mature wood was determined at the 14th annual ring from the pith.     

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     

幼龄材范围的确定及树木生长速率对幼龄材生长量的影响

本文以杉木、日本落叶松的人上林和天然林木材为对象，选择ｙ＝ａ＋ｂｌｎｘ回归模式。利用其管胞特征因子随年轮数的变化，研究划分幼龄材年轮界限的最适因子，并就生长速率对幼龄材生长量的影响进入了探讨。结果表明：杉木和日本落叶松的人工林及天然林木的管胞特征值在径向水平上的变化均遵循ｙ＝ａ＋ｂｌｎｘ模式，尤其管胞长度与年轮数回归的相关系数Ｒ均达０．９８以上；管胞长度与管胞宽度及纤丝用相比，遗传率最大，随年轮数变化的模式最稳定，是划分幼龄材界限的最佳因子，由此得出杉木人工林幼龄材界限年轮为２０－２２（距髓心距离为１２．９－１３．２ｃｍ）、天然林为１６－１８（４．１－４．５ｃｍ），日本落叶松人工林为１９－２３（８．７－１０．５ｃｍ）、天然林为２３－２４（２．９－３．１ｃｍ）；幼龄材生长量与树木生长速率成正比。     

Basic density,longitudinal shrinkage and tracheid length of juvenile wood of Picea abies (L.) Karst

Variation in the growth ring width, basic density, longitudinal shrinkage and tracheid length was investigated in the juvenile wood of Norway spruce samples taken from different heights in the stem. Annual height increments were cut from the ten youngest shoots from trees of three different heights. By this method the properties of an individual growth ring could be analysed without taking samples from each ring. Sixteen tree tops of an average stem height of 8, 15 and 25 m were analysed. Basic density was low in the first shoot, highest in the second or third one and decreased gradually thereafter. Longitudinal shrinkage was highest close to the pith and decreased to about 0.2% in the outer rings. Tracheids were only ca. 1 mm long close to the pith and their length increased sharply towards the tenth shoot. The properties of juvenile wood varied with the height in the stem. Longitudinal shrinkage around the pith seemed to increase with increasing height and basic density was highest at 25 m stem height. The applicability of the method for the calculation of basic density and tracheid length in individual growth rings close to the pith is discussed.     

Radial variation of wood density components and ring width in cork oak trees

The radial variation of ring width and wood density was studied in cork oaks (Quercus suber) using microdensitometry. The observations were made in young never debarked cork oaks (30–40 years of age) and in mature trees under cork production (37–60 years of age). The cork oak wood is very dense (mean ring density 0.86 g.cm^?3, between 0.79 g.cm^?3 and 0.97 g.cm^?3) with a small intra-ring variability (mean earlywood density 0.80 g.cm^?3 and latewood density 0.90 g.cm^?3). The density components decreased from pith to bark more rapidly until the 15th ring, and then only slightly. There were no significant differences in the mean density components between never debarked trees and trees under cork production but their outwards decrease was accentuated in the never debarked trees. The annual growth was high, with a ring width mean of 3.9 mm (4.2 mm in the first 30 years) and the latewood represented 57% of the annual growth.