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利用来自11个省区25个三尖杉种源在福建明溪和浙江安吉两试验点开展苗期测定,研究种子、苗木形态与生长性状的种源差异.方差分析结果显示:来自不同产地的三尖杉,其种子、苗木形态与生长性状差异显著.试验观测到,来自东南部地区的三尖杉种源种子较长,苗高生长量较大,分枝稀少,而中西部地区的三尖杉种源种子较短,苗高生长量较小,分枝较多.三尖杉可明显地区分为长叶和短叶两种类型,东南部的种源多为长叶类型,而中西部地区的种源多为短叶类型,间有长叶类型分布.长叶类型三尖杉种源的种长、苗高和分枝数分别为短叶类型种源的116.8%、156.2%和1.54%.相关分析发现,较之于北部的长叶类型三尖杉种源,来自于南部的长叶类型种源苗高生长量较大,地径有增大的趋势;短叶类型三尖杉种源的苗木高径生长没有明显的纬向变异模式,其地径生长与产地经度存在一定程度的正相关. 相似文献
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为了解樟树遗传变异的来源和规律,进行了樟树苗期种源/家系两水平试验研究.结果表明,樟树的遗传变异存在于种源和家系两个层次.樟树苗高、枝下高、冻害性状在种源层次的变异远大于家系层次的变异,地径则相反.方差分析表明,樟树苗期种源间在苗高、地径、枝下高、冻害性状上有极显著差异;家系之间在苗高、地径、冻害性状上有极显著差异,在枝下高性状上无显著差异,种源内大多数家系间各性状的差异达不到显著水平.苗高、枝下高、冻害各性状值,高于富阳种源(Ck)的家系分别有125、95、88、108个,低于富阳种源(Ck)的分别有56、86、93、73个.苗高与种源纬度显著负相关,与年均温、1月均温、绝对低温显著相关;冻害与纬度极显著负相关,与年均温、1月均温、绝对低温显著相关;枝下高与纬度显著相关,与年均温、1月均温、绝对低温显著负相关;苗高与冻害极显著相关,与地径显著相关. 相似文献
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对北非雪松5个种源1年生播种苗的苗高和地径生长进行研究,5个种源的苗高都符合"S"型生长曲线,苗高生长可采用Logistic生长曲线拟合,同时可把生长期划分为4个阶段;地径生长规律与苗高生长不同,Logistic生长曲线拟合程度不高,不能作为生长期划分的依据。5个种源的苗高和地径生长规律相似,但苗高和地径生长量存在显著差异,美国加利福尼亚种源和亚利桑那种源苗高、地径生长量均高于突尼斯、阿尔及利亚和摩洛哥种源。 相似文献
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为了解樟树遗传变异的来源和规律,进行了樟树苗期种源/家系两水平试验研究。结果表明,樟树的遗传变异存在于种源和家系两个层次。樟树苗高、枝下高、冻害性状在种源层次的变异远大于家系层次的变异,地径则相反。方差分析表明,樟树苗期种源间在苗高、地径、枝下高、冻害性状上有极显著差异;家系之间在苗高、地径、冻害性状上有极显著差异,在枝下高性状上无显著差异,种源内大多数家系间各性状的差异达不到显著水平。苗高、枝下高、冻害各性状值,高于富阳种源(Ck)的家系分别有125、95、88、108个,低于富阳种源(Ck)的分别有56、86、93、73个。苗高与种源纬度显著负相关,与年均温、1月均温、绝对低温显著相关;冻害与纬度极显著负相关,与年均温、1月均温、绝对低温显著相关;枝下高与纬度显著相关,与年均温、1月均温、绝对低温显著负相关;苗高与冻害极显著相关,与地径显著相关。 相似文献
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7种国外栎树引种苗期试验初报 总被引:4,自引:0,他引:4
于2000年和2001年从北美引进南方红栎、北方大果栎、水栎、柱栎、黑栎、北美白栎和英国栎等7个树种,15个种源在江苏进行育苗试验结果表明,不同树种、种源间发芽时间、场圃发芽率、苗高、地径生长性状有明显变异。种子发芽时间柱栎、黑栎依阿华和密苏里种源最早;其次为北方大果栎伊利诺斯种源、南方红栎阿肯色种源、黑栎安大略种源,水栎各种源发芽均迟。总出苗率以黑栎密苏里种源最高(达83.3%),水栎得克萨斯种源和北方栎蒙大纳种源较低(仅为15.7%和20.0%)。1年生苗高生长量以英国栎最大,其次是南方红栎、北方大果栎和水栎,黑栎和北美白栎生长量最小。同时,还研究分析比较了不同树种苗高季节生长节律。 相似文献
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不同种源任豆苗期生长性状的变异 总被引:1,自引:0,他引:1
《西部林业科学》2017,(3)
对林木苗期生长性状的研究是林木遗传育种学科领域中的重要研究内容。采用随机完全区组设计对任豆容器苗苗期生长性状进行观察和分析,研究任豆不同种源间的变异规律。结果表明,不同任豆种源间在苗高和地径生长上的差异均达到极显著水平。苗高生长量最大的是广西那坡种源,为60.53cm,最小的是云南金平种源,为40.28cm;地径生长量最大的是贵州望谟种源,为7.90mm,最小的是广西都安种源,为5.90mm。种源苗高与采种点的纬度呈正相关,与经度呈负相关;地径与采种点的纬度呈负相关,但相关性均未达到显著水平。种源苗高与采种点的无霜期呈显著的负相关,相关系数为-0.752,地径与采种点的无霜期和年日照数呈显著的负相关,相关系数分别为-0.641和-0.663。研究结果对后期任豆种源的研究与筛选提供参考。 相似文献
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Kiyohiko Fujimoto Yasushi Hiramatsu Atsushi Miyatake Kenta Shindo Masahiko Karube Masaki Harada Seiichiro Ukyo 《Journal of Wood Science》2010,56(6):444-451
The object of this study was to investigate the strength properties of edge-glued laminae and to propose a suitable grading
method based on the lamina modulus of elasticity (MOE). Edge-glued laminae composed of lumber with similar MOEs (uniform laminae)
and edge-glued laminae produced by randomly gluing lumber independent of MOE (random laminae) were made from karamatsu (Larix kaempferi) lumber having the same thickness and length, but various widths. For both the uniform and random laminae, there was a strong
correlation between MOE values measured using the longitudinal vibration technique, the static bending test, and a grading
machine. The average values of bending, tensile, and compressive strengths of the uniform laminae were similar to those of
the random laminae. On the other hand, the average strength of laminae without end joints was significantly higher than that
of finger-jointed laminae for both uniform and random laminae. Finger-joints and knots played a significant role in the failure
of specimens, but the edge-gluing and the difference in MOE within an edge-glued lamina did not appear to affect the strength
properties. The bending, tensile, and compressive strengths of edge-glued laminae were strongly correlated to the lamina MOE. 相似文献
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林木高径比是基本测树因子之一。由于精确树高测定困难(特别是在结构复杂的森林中),对林木高径比的直接相关研究相对较少。文中从林木高径比的研究对象、影响因素、林木高径比与单一测树因子的关系、林木高径比模型模拟、林木高径比与林木遭受风雪灾害的关系5个方面进行综述,以期为进一步研究林木高径比奠定基础。目前大部分研究是针对结构简单、单层同龄的人工针叶纯林,针对分树种和分林层的研究极少且只有国外报道。林木高径比可能受到树龄、树种、竞争、立地和气候等多种因素的影响。胸径、断面积、材积和地径等单一测树因子与林木高径比关系较为紧密,且呈负相关,而树高、冠长、冠幅、树冠面积、冠径、树冠比和树冠闭合百分比等单一测树因子与林木高径比关系较不紧密。目前的林木高径比模型多以胸径为自变量,然后进行多模型优选,所选的最佳模型多为非线性模型;部分研究则在最佳模型中加入其他的自变量,如竞争、立地、林层和树种等因子。多数研究认为,林木高径比越大,林木越容易遭受风雪灾害。 相似文献
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荒山生态林营造技术研究 总被引:1,自引:0,他引:1
对济南及鲁南等地区部分荒山的造林情况进行跟踪调查研究,结果显示:在济南地区,无纺布营养杯苗、鱼鳞坑种植、多树种混交在石灰岩荒山造林方面有较好的效果;在鲁南地区,在同种育苗方式下,8个树种的成活率存在显著差异,皂荚和侧柏的成活率最高,而油松和刺槐最低;第1年栽植的侧柏树高、胸径随着苗木规格的增长,生长量逐渐增加,而新梢生长是随着苗木规格的增加,生长量反而下降;通过对两种育苗方式雨季造林的成活率和树高生长量综合评价看,裸根育苗要明显优于基质育苗。 相似文献
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The Hellshire Hills are an extensive area of tropical dry forest over limestone, located on the south coast of Jamaica. Despite being a protected area, they are subject to encroachment and clearance by charcoal burners, leaving a relatively pristine core within more disturbed areas of forest. Future management requires a consideration of the forest’s resilience to such disturbance, and this study reports on coppice regrowth following clearance. The number of coppice shoots and the length and diameter at breast height (DBH) of the leading shoots were measured on tree stumps 14 months after they were cut in an experiment. Coppice regrowth after cutting was measured on a total of 476 stumps, representing 51 species. Coppice production and growth was vigorous as there was an extremely high incidence of coppice regrowth among and within the species in this forest after it had been cut. Initial regrowth was high with the diameter recovered by the leading shoots after 14 months approximating to 29% per year. Of the 51 species sampled three did not coppice at all and the average percent of individuals found with shoots within each species was 81%. The height and diameter of the leading shoots was significantly different among the species and the average height recorded of the leading shoots was 114 cm while the average diameter recorded was 10 mm. Larger sized stems (>10 cm DBH) on average produced more coppice shoots and larger sized shoots than smaller sized stems (<10 cm DBH) while smaller sized stems recovered more biomass than larger sized stems irrespective of species. The average diameter of the leading shoots decreased significantly with increasing shoot densities. At the species level there was a significant relationship between stem diameter and the number of shoots produced in seven of the 27 species analysed and three species returned significant relationships between stem diameter and average height of leading shoots. Coppice regrowth clearly offers considerable resilience to disturbance in this dry forest where successful regeneration by seed is highly susceptible to rainfall seasonality. However, the different abilities of species to produce coppice shoots will likely affect long-term species diversity if the present rate of clearance continues. 相似文献
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Akio Inoue 《Journal of Forest Research》2006,11(4):289-294
A model that describes the relationship between the form-factors for stem volume and those for stem surface area in coniferous
species is proposed. The model is derived assuming that the stem form of a tree can be expressed by Kunze's equation. The
model indicated that the form-factor for stem surface area was directly proportional to the square root of the form-factor
for stem surface volume, independent of the stem position. The proposed model expressed the relationship of the form-factors
for Japanese cedar (Cryptomeria japonica D. Don) and Japanese cypress (Chamaecyparis obtusa Endl.) trees well. Therefore, the form-factors for stem surface area could be estimated from those for stem volume. No significant
difference in the coefficient was found between Japanese cedar and Japanese cypress trees, indicating that the proportional
coefficient would be common between the two species. Many studies have shown that the form-factors for stem volume at 0.7
and 0.5 in relative height were, respectively, almost steady at 0.7 and 1.0, independent of species, district, density control,
and growth stage. Substituting these universal values into the proposed model, the form-factors for stem surface area at 0.7
and 0.5 in relative height were estimated to be 0.730 and 0.873, respectively. The estimated values of the form-factors for
stem surface area would be universal for coniferous species. The proposed model also showed that the breast height form-factor
for stem surface area decreased sharply with the increase in total tree height, when the height was less than 10 m. However,
after the tree attained the total height of 10 m, the breast height form-factor gradually decreased with the total tree height
approaching its asymptotic value of 0.605. In conclusion, the model proposed here can be used to describe the relationship
between form-factors for stem volume and those for stem surface area successfully. 相似文献
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Teak(Tectona grandis L.f.) is a popular hardwood species native to South and South-East Asia. The possible association of amplified fragment length polymorphism(AFLP) marker with morphological variables of eleven important characters viz. girth at breast height(GBH), height of tree, bole height, branch knots, presence of fluting, spiral stem, leaf hair, leaf length/breadth ratio, branching pattern, bark colour and petiole shape for nine natural populations comprising 180 genotypes of teak(9 populations × 20 trees). The phenogram constructed using Euclidean distances for the eleven morphological characters showed that the populations were not grouped according to their geographical origin. The Mantel's test for pairwise correlation between Euclidean distances of different morphological variables and genetic distances from AFLP data revealed that only petiole character(r =0.269; p =0.046) and height of tree(r =0.200; p =0.001) were significantly correlated with that of AFLP data matrix. The nine populations in this study covered a geographic area of about 1000 km stretch along the Western Ghat of South India. A test of correlation between genetic and geographic distance matrices revealed a significant positive correlation(r =0.475; p =0.009). The lack of perfect congruence between morphological and molecular data except for geographic distance, tree height and petiole character suggested that the morphological system might be useful for the morphotypes management but not appropriate to study the genetic structure of the teak populations. 相似文献
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以白皮松、油松和红皮云杉3个针叶树种1a生幼苗为对象,研究在100%全光(CK)、70%透光和40%透光3种光照下幼苗生长和根系发育规律,结果表明:不同光照条件下3个树种幼苗生长随时间变化存在不一致性,白皮松和油松高生长、地径生长均表现为全光照高于低光照处理,而红皮云杉在低光照处理下,其苗高和地径高于全光照。油松和红皮云杉根长、根系表面积、根系体积各时期发育,均表现出全光照70%透光40%透光趋势;而白皮松在根长和根系表面积方面,则为70%透光高于全光照和40%透光,在根系体积方面,全光照高于70%透光和40%透光。适度遮阴有利于白皮松幼苗生长,不利于油松幼苗生长,而红皮云杉幼苗对光照适应范围较宽。 相似文献