共查询到16条相似文献,搜索用时 62 毫秒
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毛白杨无性系木材基本密度遗传变异研究 总被引:8,自引:2,他引:6
在现代社会 ,杨树木材无论在实体木材还是纤维产品方面都发挥着越来越重要的作用。许多发达国家对杨属各树种木材材性遗传变异的研究非常重视 ,对美洲山杨 (Einspahretal.,1 972 ;Reddy ,1 983;Yanchuketal.,1 983;1 984)、美洲黑杨 (Farmeretal.,1 968;Poseyetal.,1 969;Olsonetal.,1 985)等杨树树种木材材性的遗传变异都做了较为系统的研究。我国对于杨树材性性状的遗传变异研究起步较晚 ,只对山杨 (张立非等 ,1 993;杨自湘等 ,1 994;顾万春等 ,1 994)以及黑杨派、青杨派一些杨… 相似文献
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三倍体毛白杨的木材构造与材性的研究 总被引:4,自引:0,他引:4
对三倍体毛白杨的木材构造特征、纤维形态、基本密度进行了观察记载和测定,发现其生长轮宽度达2.5~3.0cm,纤维平均长度大于同年轮的其它杨木,基本密度小于毛白杨成熟材,木纤维的含量较高,同时纤维的壁腔比较小,所以三倍体毛白杨是一种较好的造纸和纤维工业原料。 相似文献
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对河北、河南、山东、甘肃的4块毛白杨无性系测定林中约100个无性系进行了木材基本密度的测定,对木材基本密度在地点和无性系间的遗传变异进行了研究.结果表明:毛白杨无性系的木材基本密度平均值为0.4363g/cm3,木材基本密度在地点和无性系间均存在极显著差异.木材基本密度的无性系重复力为0.82~0.91,属于受遗传控制较强的材性性状.对生长和材性的相关研究表明,木材基本密度与生长性状(包括胸径、树高和材积)一般存在显著的负相关,但不同地点上表现为不同的正或负的相关关系 相似文献
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该文利用 9个 9年生三倍体毛白杨无性系木材试样 ,研究了木材气干密度组成及力学性质的遗传变异规律 .结果表明 ,木材气干密度组成及力学性质在无性系间存在显著或极显著差异 ,并受到中等强度的遗传控制 ;气干密度的径向和纵向变异与多数研究结果一致 ;力学性质除抗弯弹性模量和端面硬度外其株内变异趋势也基本符合木材学理论 .在力学性质指标中 ,抗弯弹性模量和弦面硬度是遗传性很强的性状 ,其无性系重复力分别为 0 90和 0 80 ,抗弯强度、顺纹抗压强度和硬度的无性系重复力稍低 .遗传相关表明对单板材可通过木材密度与干形等形质指标进行优良无性系选择 相似文献
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三倍体毛白杨超短轮伐纸浆材基本密度及化学成分分析 总被引:2,自引:0,他引:2
以超短轮伐栽培的3年生三倍体毛白杨无性系为试验材料,在分析超短轮伐纸浆材基本密度以及化学组分的基础上探讨超短轮伐期栽培的可行性。结果表明:三倍体毛白杨无性系对超短轮伐纸浆材基本密度影响极显著,造林密度对超短轮伐纸浆材基本密度影响显著,3年生超短轮伐纸浆材基本密度在0.247~0.282g·cm-3之间变化。无性系对超短轮伐纸浆材聚戊糖含量、木素含量、综纤维素含量以及α-纤维素含量影响显著,而造林密度以及无性系与造林密度间相互作用对超短轮伐纸浆材化学组分的影响均不显著。超短轮伐纸浆材的苯醇抽出物含量介于3.68%~4.39%之间,戊聚糖含量介于12.86%~13.47%之间,木素含量介于18.16%~19.77%之间,综纤维素含量介于74.91%~77.61%之间,α-纤维素含量介于40.28%~43.49%之间。 相似文献
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以三倍体毛白杨不同密度试验林为研究对象,采用随机区组试验设计研究了4 a生长期内5个不同密度(2 m×2 m、2 m×3 m、2 m×4 m、2 m×5 m和3 m×4 m)试验林的0 20、20 40、40 60 cm土壤层次的理化指标(pH值、有机质、全N、碱解N、全P、有效P、全K和速效K含量),结果表明:(1)4 a生长期内,三倍体毛白杨各密度试验林3个土层的pH值均增加,尤其是低密度(3 m×4 m)试验林增幅最大,且随土层加深碱性增强。(2)各密度试验林3个土层有机质含量呈先降后升的变化,高密度(2 m×2 m、2 m×3 m)试验林有机质消耗量显著比其它密度的大。(3)土壤全P和有效P含量呈先升后降的变化特点,高密度(2 m×2 m)试验林有效P消耗量显著比其它密度的大。(4)高密度(2 m×2 m)试验林土壤碱解N含量增幅显著;中、低密度(2 m×4 m、3 m×4 m)试验林土壤速效K含量降幅显著;其它养分指标无明显变化规律。 相似文献
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ZhangZihui ZhangZhiyit LinShanzhi LiXinguo 《中国林学(英文版)》2003,5(2):23-29
Effects of seven planting densities on the growth and tree form of nine 5-year-old new clones in Populus tomentosa were studied. The plantations, arranged with completely random block design, were located in Wuzhi County, Henan Province.Results indicated that effects of planting density on the diameter at breast height (DBH), individual volume and growing stock increment of all new clones in P. tomentosa were significant at the 1% level of probability, effects of planting density on the tree height increment of new clones B2 and B31 and on the live branches height (LBH) increment of new clones B5 and B30 were significant at the 5% level of probability, while the interaction between planting density and clone was not significant at the 5% level of probability. It was concluded that the degree of differences among new clones within the same planting density was different with different planting densities and traits. For short rotation industrial timber, clones B 1, B3, B4, B5, B7, B9, B31 were suitable with the density of 1 000-2 500 trees per hectare, while for bigger diameter timber, clones B1, B3, B4, B7, B9, B31 could be used with the planting density of 660-833 trees per hectare. Clonal repeatability was also different in different planting densities. 相似文献
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In order to understand the structural characteristics of lignin in triploid clones ofPopulus tomentosa and its changes in the processes of pulping and bleaching, milled wood lignin (MWL), lignin carbohydrate complex (LCC) and the residual lignin from kraft pulp (KP) and sulfite pulp (SP) were isolated and analyzed by Fourier transform infrared (FTIR) spectrum and ^13C nuclear magnetic resonance (NMR). The most diagnostic peaks were assigned and the differences were discussed. The spectral patterns reveal that triploid P tomentosa shows the specific features of hardwood from temperate areas, but in the spectrum of FTIR, the strength ratio orAl270 cm^-1 to A1226 cm^-1 is 0.88, higher than the average of hardwood from temperate areas, which will make the lignin delignification more difficult during pulping and bleaching. The LCC from triploid P tomentosa is mainly composed of xyloglucan and glucuronic acid, and other glucides have much lower ratio. In LCC FTIR, there are three peaks at 1 427, 1 329 and 1 046 cm^-1, indicating that both semi-cellulose and cellulose could exist in LCC, and that there might be relationships between cellulose and lignin. Compared with the residual lignin from KP and SP, the condensed structure in KP is more than that in SP. 相似文献
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根据10年来大规模的三倍体毛白杨春、秋、冬三季造林,总结出了通道工程绿化、农田林网和滩涂用材丰产林的整地、苗木质量标准、栽植八要诀、育造一体化和林木管理等系列配套造林技术。参照应用本技术,可使毛白杨造林成活率达到95%以上,并使三倍体毛白杨产业的经济效益提高三倍以上,具有很高的推广价值。 相似文献
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WangLixian LiuYong ZhangZhiyi 《中国林学(英文版)》2003,5(3):13-20
With four clones of triploid Populus tomentosa as materials, the effects of fertilization treatment on growth and physiological characters in terms of leaf nitrogen content, phosphorous content, potassium content, net photosynthetic rate,transpiration rate, water utilization efficiency and chlorophyll content have been studied. Compared with the general fertilizer as a control, the long-effect fertilizer, especially for Populus, produce more favorable results, for P. tomentosa on sandy land. 相似文献
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