国产重要阔叶树村纹孔的超微构造研究

利用直接碳复型和超薄切片技术，在透射电镜下观察了我国与种（隶２８属、１５科）阔叶树材的纹孔超微构造。其中有１０种（隶８属、４科）木材维管间具缘纹孔膜具纹孔塞，其余不具纹孔塞。纹孔膜上微纤丝排列有３种类型：随机排列、辐射状排列、平行排列。维管间具缘纹孔室内有５种具附物，１９种具瘤状物。以上特征有木材识别价值。在新鲜材和部分脱木素的试样中１７种木材的管间具缘纹孔膜和半具缘纹孔膜有明显开孔，直径０．０４—０．１９μｍ。新鲜村单纹孔的纹孔膜有胞间连丝存在，膜上有微孔。还讨论了阔叶树材具缘纹孔在系统发育中的变化。     

国产重要阔叶树材纹孔的超微构造研究

利用直接碳复型和超薄切片技术，在透射电镜下观察了我国４５种（隶２８属、１５科）阔叶树材的纹孔超微构造。其中有１０种（隶８属、４科）木材维管间具绷纹孔膜具纹孔塞，其余不具纹孔塞。纹孔膜上微纤丝排列有３种类型：随机排列、辐射状排列、平行排列。维管间具缘纹孔室内有５种具附物，１９种具瘤状物。以上特征有木材识别价值。在新鲜材和部分脱木素的试样中１７种木材的管间具缘纹孔膜和半具缘纹孔膜有明显开孔，直径０．０     

国产主要阔叶树材导管和纤维瘤状层的电镜观察和研究

对我国１８２种（４８科１３５属）阔叶树材导管和纤维壁的内表面进行扫描和透射电镜观察，其中５０种（隶１７科３２属）有瘤状层存在，其余不见或罕见。就这５０种木材的瘤状层有无及其形态和分布进行深入的观察与探讨。并对２种木材的超薄切片进行透射电镜观察和分析，认为瘤状物与次生壁的电子密度不同，说明两者化学成分不同。此外，还讨论了瘤状层的分布与穿孔板类型和在生长轮的位置关系。未发现瘤状层的出现和木质部进化趋势     

国产重要树种木材特征及其出现频率的研究

研究了国产（包括引种的）６６９个重要树种的木材特征及其出现的频率。涉及裸子植物木材（或针叶树材）１６９种、木材特征１３８个，被子植物木材（阔叶树材）５００种、木材特征１７８个，并列出具有特殊木材特征的树种。     

阔叶树材导管分子螺纹加厚的电镜观察与探讨

从国产１７７科阔叶树（隶４５科１３２属）木材构造的电镜观察中筛选出５１种（隶２０科４４属）木材的导管、维管管胞内壁上具有螺纹加厚，对所观察到的螺纹加厚进行了比较，在国外学者将螺纹加厚分为三种类型的基础上，近一步分为四种类型：１．分枝型；２．不分枝型；３．涡流型；４．附物型。其中分枝型和不分枝型又分为Ⅰ型和Ⅱ型。同时对螺纹加厚的形成和分布进行了讨论。     

东北阔叶树材的利用

东北阔叶树材的利用王桂荣，吴庆，王春祥（黑龙江省森工管理干部学院）东北现有阔叶树材近４２种，被人们广泛开发和利用的阔叶树材约２０种。随着天然林珍稀树种的减少．优质木材资源短缺的状况会越来越明显。因此．充分合理地利用现有阔叶树材，对缓解木材资源短缺的状...     

东北常见树种木材形成早期组织波谱特征差异分析

【目的】研究东北主要商品材树种木材形成早期组织的化学特征及其在树种间的差异,为揭示树木生长过程中木材细胞壁的自组装行为和木材形成的分子机制提供科学依据。【方法】选取东北10种重要商品材树种,采集木材形成早期组织,利用红外光谱和X射线衍射技术分析木材形成早期组织的波谱特征。【结果】红外光谱差别主要在波数900～2 000 cm~(-1)之间的指纹区域。针叶树种木材中波数1 735 cm~(-1)附近由木聚糖乙酰基C O伸缩振动引起的吸收峰相对强度显著小于阔叶树种木材。针叶树种木材中1511cm~(-1)处表征苯环碳骨架振动的吸收峰较明显,尤其是云杉和落叶松。针、阔叶树种木材在波数1 630～1 660 cm~(-1)之间均出现不同强度的吸收峰,峰形较宽,该峰归属为蛋白质肽段中氨基化合物振动引起。红外光谱二阶导数处理后,针叶树种木材在波数1 266 cm~(-1)处有明显吸收峰,阔叶树种木材中并未发现,该峰归属为愈创木基环加CO伸缩振动。而阔叶树种木材在1245cm~(-1)处有较明显吸收峰,该峰由木质素紫丁香基环振动引起。多数树种木材X射线衍射图谱I002有较强的衍射峰,但Iam的衍射峰并不明显,尤其是阔叶树种木材。因此推测木材形成早期组织中纤维素的晶型、晶胞或晶区大小与成熟木材不同。【结论】针、阔叶树种木材形成早期组织中木质素和半纤维素的沉积过程有所差别,这有助于揭示木材形成过程中化学成分和结构的变化规律。     

红木识别

文章介绍了17种红木（Rosewoods）家具用材树种的木材宏观构造识别特征,并注明了树种的隶属科、属、种的中文名、拉丁学名、商品材名和主产地。     

论我国南方发展珍优阔叶树大径材人工林

发展珍优阔叶树大径材人工林适应了我国木材需要，是南方森林可持续经营的重要手段，列举了南方珍优阔叶树种28科75种，分析了保障珍优阔叶树大径材人工林发展的科技和政策支撑条件。     

华南壳斗科木材分类的研究

华南地区地处热带北部至中亚热带，包括广东、广西和海南三省（区）。华南壳斗科树种很丰富，为阔叶村第一大科，其蓄积量占阔叶材约１／３，采伐量及木材利用均属阔叶材首位。本文将华南壳斗科木材归并为１４类，有分类检索表、分类树种志要、材性及用途表。     

Water storage capacitance and xylem tension in isolated branches of temperate and tropical trees

Trees of tropical semi-deciduous forests range from "drought-avoiding" stem-succulent species with low-density wood (< 0.5 g cm(-3)), which maintain high stem water potentials (psi(STEM) > -0.7 MPa) throughout the year, to "drought-tolerant" deciduous hardwood species (wood density > 0.75 g cm(-3)), which dehydrate strongly during seasonal drought (psi(STEM) < -6 MPa). In stem-succulent and other drought-avoiding species, xylem vessels are surrounded by extensive parenchyma providing intracellular water storage, whereas in deciduous species stem water storage is mainly extracellular. Thirteen tropical and two temperate tree species, representing different functional types, were studied. The contribution of stem water storage to these species' water use during water stress was determined by time-series analysis of dehydration and rehydration of excised leaf-bearing branches of these trees. During dehydration, stem water potential slowly declined 1-2 MPa in drought-avoiding species, but in deciduous species it rapidly fell 4-5 MPa, suggesting that water storage capacitance was related to xylem anatomy. After immersion of dehydrated, leafless branches in water, the decline in xylem tension and rate of water uptake during rehydration were linearly related, as predicted by application of Ohm's law to water flux. The decline of xylem tension during rehydration was biphasic, with a phase of rapid water uptake into extracellular spaces being followed by a prolonged phase of slow water uptake into living cells. The rate of water uptake during rehydration and the minima of leaf water potential observed in the field during the dry season were highly correlated with water storage capacitance, indicating that wood anatomy is a major determinant of drought adaptation.     

Observations of trabeculae in New Zealand hardwoods

Summary During a survey on the anatomy of New Zealand native woods, trabeculae were observed in the xylem cells of 6 hardwood species endemic to New Zealand. They were not found in a further 216 species. In some species they were observed only in the vessel members while in others they occurred in the vessel members, fibres and axial parenchyma cells. Their diameter is proportional to the thickness of the host cell wall. The similarites and differences between these trabeculae and those described as occurring in softwoods and other hardwoods are discussed. No explanation is proposed for their origin.We are indebted to the Conservators of Forests for Nelson and Westland, and to the Egmont, Abel Tasman, Urewera and Arthur's Pass National Park Boards for permission to collect wood samples; and also to Mr R. R. Exley, Physics and Engineering Laboratory D.S.I.R. for technical assistance.     

植物激素与木材形成

综述了植物激素在树木维管组织分化中的作用．生长素是调节木质部细胞分化的主要因子；细胞分裂素在诱导分生组织发端和分生细胞分化上起重要作用；赤霉素促进纤维的形成，赤霉素和生长素结合使用，可有效地促进次生木质部中纤维分化；乙烯能促进树木韧皮部和木质部分化。还讨沦了木材形成过程中的三个主要问题：生长素含量的多少直接控制了沿树轴木质部导管、管胞的大小和密度；外界环境因子影响木质部细胞分化；温带落叶阔叶树环孔材和散孔材形成的机理，生长素控制环孔材树种早材宽导管的形成以及晚材窄导管和纤维形成的假说。对今后改善树木木材的质和量上有一定参考价值。     

米槠等8个阔叶树种造林生长状况的初步研究

对米槠等8个阔叶树种进行造林试验,结果表明:参试树种3年生树高存在极显著差异,以闽粤栲和米槠最好,与杉木相当,达2 5m左右,其次为拉氏栲和木荚红豆树;8年生幼林材积生长量也以米槠(44 8m3·hm-2)和闽粤栲(42 2m3·hm-2)为最好,其次是丝栗栲(28 7m3·hm-2)和拉氏栲(28 1m3·hm-2)。从适应性和生长量的角度来看,参试树种的大小排序为米槠、闽粤栲>丝栗栲、拉氏栲>深山含笑、木荚红豆树、细叶香桂>少叶黄杞。其中米槠、闽粤栲、丝栗栲和拉氏栲等4个树种适宜做为优质阔叶用材树种进一步推广造林。     

Differences in bird species diversities between a natural mixed forest and a coniferous plantation

Bird species diversity and bird species richness were surveyed in a natural mixed forest (mature forest) and in a coniferous plantation (30–40 years old) monthly from 1990 to 1994. These forests were 20 km apart and had similar weather conditions and soil types. There were larch and cedar plantations, and hardwoods along streams in the coniferous plantation. In the natural mixed forest, 55 bird species were found, whereas 40 species were recorded in the coniferous plantation. The species diversity of bird communities was significantly higher in the natural mixed forest than in the coniferous plantation mixed with hardwood trees. This result indicates that the coniferous plantation mixed with hardwood trees, presumed to be a more simplified environment, is likely to be less inhabitable for many bird species than the natural mixed forest, suggesting a relationship between the diversity of the forest environment and the diversity of the bird community. A higher number of bird species was recorded in the small coniferous forest mixed with hardwood trees compared with those in the coniferous plantation. The mixing of broad-leaved trees in a coniferous plantation was suggested to be effective in increasing number of bird species. These tendencies were recorded all through the year during our study. In snow-covering periods, both the diversity and the bird species richness fell in all study sites every year. Snow cover would have greater effect on bird species diversity in the coniferous plantation than in other forest types probably due to diet shortages caused by the snow cover over the forest floor.     

The fractal estimation of wood color variation by the triangular prism surface area method

Color variations of the surfaces of fifteen wood species were characterized by fractal dimension of the triangular prism surface area method. Softwood and hardwood indicated apparently different in the mean fractal dimensions of red and green colors. Red color behaved steadier in softwood than in hardwood and green color varied comparatively stronger in hardwood than in softwood. No evident differences between softwood and hardwood were found in the variation of blue color of all the specimens. Following the low-to-high value order of the mean fractal dimensions, three types of combination of red (R), green (G) and blue (B) colors were found: RGB, RBG and BGR. There also existed six types of fractal dimension distribution; namely, plane, included plane, concave, convex, zigzag, and hilly distributions. Fractal dimensions across the grain changed greatly whereas those along the grain became relatively steady. The characteristic difference of color variation was defined for each species, which was inferred to characterize its own unique appearance of surface color. For color matching of wood parts, fractal dimension quantitatively furnishes essential information of color variation in local and overall features. Such evaluation can be efficiently carried out with few measurements along the grain and by detecting a single color (red, green or blue) only. Received 5 May 2000     

Effect of the lateral growth rate on wood properties in fast-growing hardwood species

We investigated the feasibility of using several fast-growing tropical or subtropical hardwood species for timber production by measuring key wood qualities in relationship to the high rates of lateral growth. The trees tested were sampled from even-aged plantations of Acacia mangium, A. auriculiformis, hybrid Acacia (A. mangium × A. auriculiformis), Eucalyptus grandis, E. globulus, and Paraserianthes falcataria (Solomon and Java origin) that had already reached commercial harvesting age. The released strain of the surface growth stress (RS), xylem density (XD), microfibril angle (MFA), and fiber length (FL) were measured at the outermost part of the xylem at breast height in each tree. Results were then compared to the lateral growth rate (radius/age) at breast height, which provides a relative indicator of the amount of tree growth per year. Our findings indicated that RS was constant, regardless of lateral growth rate in each species. Similar results were observed for XD, MFA, and FL, with a few exceptions, suggesting that high growth rates do not intrinsically affect the wood properties of fast-growing tropical or subtropical species that have reached harvesting age. However, special attention must be paid to patterns of xylem maturation when developing plantations of such species.     

Occurrence of decay-associated xylem suberization in a range of woody species

Suberization responses to naturally-occurring fungal colonization of living xylem tissues were detected in 30 of 37 woody species examined. These responses comprised the suberization of traumatic parenchyma tissues in compartmentalization wall 4 barrier zones laid down in the vicinity of fungally infected wounds, or the suberization of parenchyma cells, tyloses and vessel linings in reaction zone decay margins in fully differentiated sapwood. Additionally, in a few species, suberization of xylem fibres and tracheids was observed where juvenile xylem tissues, apparently still incompletely differentiated, had been exposed by wounding. These xylem suberization responses are considered to increase the decay resistance of the altered cells, and may protect the hydraulic integrity of adjacent tissue, thus contributing to the antimicrobial defence of the living sapwood.     

Warts in the evolution of angiosperm wood

Summary The occurrence and distribution of the warty layer in twelve species of hardwoods have been investigated by transmission and/or scanning electron microscopy. Samples were selected on the common feature of reportedly having both primitive vessel types with scalariform perforation plates and more evolutionarily advanced vessel types with simple plates. Among the six angiosperm families represented, warts were generally found in the more primitive-type vessel elements. The more advanced vessel types rarely displayed a warty layer. Warts were also sparse or absent in other specialized cells, the fiber tracheids and libriform fibers. From the evidence presented here and in the literature, the variable presence and morphology of the warty layer in hardwoods (or for wood in general) appears to be attributable to a phylogenetic trend. According to this trend, conifer tracheids and primitive hardwood cells are nearly always warted, but as the cell type becomes more advanced or specialized, it becomes increasingly wart-free.     

Effects of management, environment and landscape conditions on establishment of hardwood seedlings and saplings in central Japanese coniferous plantations

There is an increasing need to restore natural hardwood forests in landscapes dominated by monocultural conifer plantations. A convenient restoration approach is to exploit natural regeneration processes. Natural regeneration, however, is affected by diverse interacting factors, for which better understanding is required, in order to optimize restoration programs. To identify optimal management practices for improving natural regeneration of hardwood trees in coniferous plantations, we examined the effects of multiple factors on the abundance of seedlings, small saplings and large saplings (height <0.3, 0.3-1.3 and ?1.3 m, respectively) of hardwood tree and shrub species in both line thinned (LT) and unthinned (UT) plantations of sugi (Cryptomeria japonica) and hardwood forests (HF) in central Japan. The effects of management practices (number of the times of weeding and cleaning, thinning method, years after thinning and forest age), environment (slope position, slope angle and canopy openness), and landscape conditions (distance from nearest hardwood forest, altitude and landuse before planting) on the number of hardwood individuals were examined by using the data obtained from the LT plantations. We also compared hardwood density between LT and UT plantations to examine the effect of line thinning. Finally, we examined species composition of LT plantations and HF to identify hardwood forest components in the thinned plantations. The effects on hardwood regeneration of environmental conditions, landscape factors and management practices applied in the plantations varied, depending on the size class and life form of the regenerating species. The abundance of large saplings of tall tree species was affected by several management factors, especially number of the times of weeding. Landscape conditions (distance from the nearest hardwood forest and altitude) affected the abundance of small saplings and seedlings of tall tree species, but not the other classes. Seedlings and small saplings of many tall tree species that contribute to hardwood forest canopies were less abundant in the LT plantations. The results show that numerous factors affect the establishment and abundance of naturally regenerating hardwood tree species, and suggest that successful establishment during early plantation stages can have long-lasting effects on natural regeneration of tall tree species.