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1.
HUANG Luohua QIN Tefu Research Institute of Wood Industry Chinese Academy of Forestry Beijing P.R.China 《中国林业科技(英文版)》2007,6(3):55-59
The variability of main chemical composition of radial Chinese fir was studied. Analysis of variance showed that variance was significant, especially for holocellulose and α-celluloSe; the hblocellulose content in heart wood was lower than that in sapwood; the lignin content decreased from Position t to Position 3, but increased gradually from Position 4 to Position 8; the a ~ cellulose content in heart wood was lower than that in sapwood; and the relative crystallinity was 59.97% in Position 1, 60i80% in Position 2, and about 42% in others. 相似文献
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分析了杉木第3代和第2.5代种子园良种苗木生长,认为杉木良种苗木的生长优势主要体现在苗高和Ⅰ级侧根数上。尤溪杉木第3代种子园良种和沙县官庄杉木第2.5代种子园良种1a生裸根苗苗高分别为0.51m和0.49m,分别比人工林采集种子的苗木高27.5%和22.5%。Ⅰ级侧根数量分别为23.33条和24.67条,分别比人工林采集种子的苗木多32.86%和40.49%。而尤溪第3代良种与官庄第2.5代良种苗木间地上部分和根系生长差异均不显著。 相似文献
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通过6a试验,提出了杉木幼林与大豆立体复合经营模式,其中包括:选择抗旱、耐瘠、高产稳产、适宜杉木幼林立体经营的大豆良种(本试验从78个品种中筛选出6个优良品种),适时播种(春大豆4月1日~15日,夏大豆5月15~25日),合理的株行距(20~50cm)和每个播种穴合理留苗数(2~4株/穴),用钙镁磷出作基肥(225kg/hm2),因地制宜施少量氮肥(尿素37.5~75.0kg/hm2),适宜立体复合经营的杉木幼林应为造林后1~2a,林地应为阳坡,豆株与幼树的距离33cm以上。杉木—大豆立体经营,不仅能增加粮食和直接经济收入,而且提高了光能利用率,改善林地小气候,减少林地水土流失,改良了土壤,使杉木幼林年生长量比一级提高20%左右。 相似文献
4.
杉木大径材定向培育良种效应研究 总被引:3,自引:1,他引:3
种苗是林业生产的重要物质基础,选用良种造林是实现林木速生、丰产、优质的重要措施。通过对江西铜鼓、永丰、德兴3个杉木主要造林区1987~1991年营造的杉木速生丰产林进行良种造林对比试验,结果表明:在相同的经营条件下,由种源到优良种源中的优良无性系造林具有种质的叠加效应,其叠加效应在胸径和材积生长上表现尤为突出,优良种源培育大径材比普通种源材积生长要提高30%左右,而用优良种源中选育出的优良无性系培育大径材,在种源的基础上又要提高20%以上,且林分大径木比例明显增加。 相似文献
5.
对10个10年生日本落叶松无性系的早材和晚材微纤丝角进行了测定,结果表明:早、晚材微纤丝角无性系间差异极显著,同一年轮内早材微纤丝角大于晚材.日本落叶松微纤丝角的径向变异规律为:在髓心处最大,以后逐渐减小.早、晚材微纤丝角与树木年轮间的变异模式(径向变异)以对数和乘幂式方程拟合效果较好,R2(R为相关系数)均在0.8以上.早、晚材微纤丝角同树高、形率、树皮厚度、主枝粗、枝干比、主枝夹角、主枝长的相关关系不显著,早、晚材微纤丝角同胸径、冠幅的相关关系达到显著水平;早材与晚材的微纤丝角也相关显著.早材和晚材的微纤丝角受中到强度遗传控制,广义遗传力分别为0.767 4、0.804 3.按照20%的选择率,早材和晚材的微纤丝角的遗传增益分别为21.82%和29.75%. 相似文献
6.
GUO Wei REN Haiqing YIN Yafang Research Institute of Wood Industry Chinese Academy of Forestry Beijing P.R.China 《中国林业科技(英文版)》2007,6(2):36-40
As one of the most important plantations, Chinese fir has drawn more and more attention from domestic wood researchers. And as the development and increasing of plantation resource of Chinese fir, research and development of the product will become a hot point. In this paper, we chose 1 571 pieces of structural lumbers from 4 areas to research grading. After sawing, drying and dressing, the lumbers were separated into 3 main grades by GB50005-2003 Code for Design of Timber Structures, namely SS, No. 1 and No.2. The conclusions are that knot as the maximum strength reduced defect (MSRD) is a main character in the lumber, the visual quality of Fujian structural lumbers is polarized, and the applicability of visual grading to the lumber is poor, so we hold the point that we should adjust the grading rules to gain a better grading result. 相似文献
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在福建南平第1代杉木成熟林中设置固定标准地,采伐前测定每个标准地碳储量,采伐后采用5种方式处理采伐剩余物:全部收获(移走地面上全部有机剩余物,包括树木、林下植被和枯枝落叶)、全树收获(收获树木的全部地上部分)、树干和树皮收获(仅收获树干与树皮)、加倍采伐剩余物(仅收获树干和树皮,将全树收获处理的树枝和树叶移到这个处理中)、炼山(仅收获树干和树皮,然后火烧采伐剩余物),随后采用常规方法营造第2代杉木林。试验后12 a,对不同处理生态系统碳储量进行研究。结果表明:12年生第2代杉木林乔木层碳储量大小顺序为:加倍采伐剩余物(61.03 t·hm-2)>全树收获(57.57 t·hm-2)>全部收获(55.64 t·hm-2)>树干和树皮收获(54.38 t·hm-2)>炼山(49.00 t·hm-2);土壤层(0~40 cm)碳储量大小顺序为:加倍采伐剩余物(99.49 t·hm-2)>全树收获(95.63 t·hm-2)>树干和树皮收获(94.81 t·hm-2)>全部收获(91.55 t·hm-2)>炼山(91.23 t·hm-2,与第1代杉木林采伐前相比,第2代12年生杉木土壤层(0~40 cm)碳储量除了全部收获处理降低0.04 t·hm-2外,其他处理均有少量增加,但差异均不显著。第2代12年生杉木林生态系统总碳储量大小顺序为:加倍采伐剩余物(162.80 t·hm-2)>全树收获(155.56 t·hm-2)>树干和树皮收获(151.24 t·hm-2)>全部收获(149.14 t·hm-2)>炼山(142.29 t·hm-2)。加倍采伐剩余物处理、全树收获处理、树干和树皮收获处理、全部收获处理生态系统碳储量分别比炼山处理高14.41%、9.33%、6.29%、4.81%,但差异均达不到显著水平(P>0.05)。 相似文献
8.
杉木无性系生长和材性变异及多性状指数选择 总被引:11,自引:0,他引:11
对19年生和17年生2块杉木无性系测定林开展生长和材性变异及多性状指数选择研究,其中,19年生测定林包括38个参试无性系,17年生测定林包括102个参试无性系。2块测定林数据分析结果均显示:无性系树高、胸径、单株材积、心材率和木材基本密度存在极显著的遗传差异,无性系重复力达中等偏上至较高水平,遗传变异系数各性状间差异较大;树高、胸径、材积生长性状间存在极显著的表型和遗传相关,与基本密度存在弱负相关。不同选择方法的结果表明,指数选择能整体提高单株材积、心材率和木材基本密度综合的遗传增益,达到比单性状选择更好的选择效果,是多性状改良较理想的选择方法。 相似文献
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The microfibril angle (MFA) of seven poplar clones was determined using X-ray diffraction technique. MFA was measured for
every growth ring at breast height (1.3 m) for all sample trees, and at 0 (butt), 5.6, 9.6, 13.6, 17.6, 19.6 and 21.6 m for
clone I-69, Nanlin-95 and Nanlin-895. A total of 900 samples (chips) were assessed. Significant variation was observed among
poplar clones and growth rings. Mean clonal MFAs at the breast height ranged from 15.2° to 21.0°. MFA at breast height varied
from 7.8° to 28° between growth rings and showed a consistent pith-to-bark trend of declining angles. Disc-average microfibril
angle in poplar clones declines rapidly from 0 to 5.6 m height, after which, it is near constant within tree height. Significant
variation was also observed in disc-average MFA among tree heights. Correlation analysis showed that the correlation between
MFAs from rings 5 to 11 at breast height was significant, while whole-tree values of each growth ring were significantly correlated
with the corresponding MFA at breast height. The results of this study provide some basis for genetic selection of poplar
trees based on wood-quality criteria and for devising appropriate sampling strategies for MFA measurement. 相似文献
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借助9年生杉木种源个体2水平试验林,研究了若干经济性状的遗传变异规律,结果是:①杉木不同种源间存在着明显的遗传差异,这是种源选择的依据;②种源内株间变异量>种源间变异量;③种源的遗传力>种源内株间个体的遗传力;④在相同的研究性状上,种源的选择进展>种源内个体的选择进展;⑤在相同的变异层次上,不同性状的选择进展各异;⑤单纯的种源选择方案产生的选择进展,比种源内个体的选择进展要大,但比优良种源内选择优良个体方案所产生的选择进展要小。 相似文献
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实心瓜多竹(Guadua amplexifolia)隶属于瓜多竹属(Guadua),丛生,是南美洲主要栽培竹种之一,广泛分布于哥伦比亚、厄瓜多尔、巴西、阿根廷等国,竹材基部实心,高25m,径15cm左右,是较好的建筑用原料,耐短期零度低温,适应我国热带、南亚热带或中亚热带与南亚热带过渡区的气候条件(邹跃 相似文献
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在对张家界国家森林公园的成熟杉木人工林现状调查的基础上,提出按照景观生态学、森林美学原理,采取卫生抚育、透视抚育等手段,通过人工营造近自然混交林,结合地貌、景观效果分批进行带状条状不同程度的间伐,改造林相提高林分质量,增强森林生态防护功能,维护生态平衡。 相似文献
14.
XU Ming REN Haiqing LUO Xiuqin YIN Yafang Research Institute of Wood Industry Chinese Academy of Forestry Beijing P. R. China 《中国林业科技(英文版)》2006,5(4):27-32
INTRODUCTION Chinese fir (Cunninghamia lanceolata) is a very important timber species in the southern China (Shi Jisen et al. 1987). It is good, fast-growing, and exempts from serious plant diseases. Its plantation is big in terms of size in the South of China and its storage stock is very rich, which is about 20% of the national commodity wood (Zhou Shuangquan et al. 2000). And the lumber becomes mainly commercial construction materials in China because of straight grain, light and so… 相似文献
15.
杉木萌芽纯林与混交林生长量及经济效益的研究 总被引:1,自引:0,他引:1
在杉木林采伐迹地上,通过不炼山、套种火力楠与深山含笑,进行杉木萌芽纯林与混交林的对比试验,9a试验结果表明:混交林中杉木的平均胸径、树高、单株材积、地上部分单株生物量分别比杉木萌芽纯林增加4 04%、8 75%、16 3%、1 43%;混交林中火力楠和深山含笑生长良好,混交林总蓄积量和乔木层地上部分总生物量分别为杉木纯林的1 47倍和1 32倍;混交林的投入产出比高于杉木萌芽纯林,说明本模式是恢复和提高杉木连栽地土壤生产力的可行方法。 相似文献
16.
无性系杉木木材物理性质研究 总被引:1,自引:0,他引:1
对金洞林场杉木无性系19年生(不含苗龄)的木材物理性质研究,结果表明:杉木优良无性系木材的基本密度、径向干缩率、弦向干缩率、体积干缩率分别是0.279 g.cm-3、2.90%、5.10%和7.85%;整个无性系的基本密度、径向干缩率、弦向干缩率、体积干缩率分别是0.301 g.cm-3、3.28%、5.26%和8.27%;而对照CK的基本密度、径向干缩木材基率、弦向干缩率、体积干缩率分别是0.275 g.cm-3、2.80%、5.10%和8.00%.研究证明:杉木优良无性系不但木材产量高,而且木材质量也并不比当地实生苗差.选用杉木优良无性系造林,不但能增加木材产量,而且材质也不会因速生而变劣. 相似文献
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LV Wenhua ZHAO Guangjie. Research Institute of Wood Industry Chinese Academy of Forestry Beijing P. R. China . College of Material Science Technology Beijing Forestry University Beijing P. R. China 《中国林业科技(英文版)》2006,5(1):33-39
INTRODUCTIONWood possesses many special properties, such asbeautiful grain, natural color, high strength-to-weightratio, good electricity and heat insulation; and it can beeasily processed, glued or dyed. It is biodegradable,recyclable and environmental-friendly (Wang Tianminet al. 2002). But as a biomaterial, it also has intrinsicdefects as easy decaying, burning and deforming,which largely limits its usage. Nano science andtechnology opens a completely new way to developwood composites… 相似文献
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介绍了一种新的测量木材微纤丝角的无损检测技术--近红外光谱分析,并详细阐述了测量时木材样品的选择及制备,测量工作包括X射线衍射和近红外光谱采集、多变量数据分析与模型建立的方法及步骤.证明了近红外光谱分析技术可以用于快速准确地预测木材的微纤丝角. 相似文献
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OHIRA Tatsuro 《中国林业科技(英文版)》2006,5(3):13-16
Volatile organic chemicals (VOCs) are emitted as gases from certain solids or liquids, which include a variety of chemicals, some of them may have short- and long- term adverse health effects. Concentrations of many VOCs are consistently higher indoors (up to ten times higher) than outdoors. VOCs are emitted by a wide array of products numbering in the thousands, for example: paints and lacquers, paint strippers, cleaning supplies, pesticides, building materials and furnishings, office equi… 相似文献