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对冷杉林分的生长过程、形成原因和功能特征进行了分析 ,建立了冷杉低质低效林综合等级的判别函数 ,将林分划分为4种类型 :极低质低效型、生长潜力型、低质型、综合低质低效型 .对林分立地因子的逐步回归分析表明 ,在其分布区域内 ,影响冷杉生长的主导立地因子除了海拔和坡向外 ,依次为土壤名称、土层厚度和坡位 ,而坡度对其影响较小 .它们的组合可以构成不同的立地条件类型 .根据对各等级的林分生长过程及其立地特征的分析 ,提出了划分冷杉低质低效林的技术参数标准 相似文献
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百山祖冷杉森林植物群落的外貌与结构特征研究 总被引:5,自引:1,他引:5
百山祖冷杉森林植物群落的优势种群是由常绿的多脉青冈和落叶的亮叶水青冈组成,是一个比较特殊的天然的常绿与落叶阔叶混交林.构成乔木层的树种有8 ~ 9种,分为3个亚层,第1亚层高13m,由百山祖冷杉组成,第2亚层高8 ~ 12m,由多脉青冈和亮叶水青冈优势种群构成主要林冠层,第3亚层高4 ~ 8m,主要由第2亚层优势种群的幼树组成.百山祖冷杉植物群落的物种丰富度为17 ~ 19种,乔木层物种多样性指数明显高于灌木层和草本层,灌木物种主要由箬竹和百山祖玉山竹组成,草本物种主要为莎草科的苔草. 相似文献
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采用XAD2吸附法和GC/MS法,对急尖长苞冷杉球果、枝条及小果垂枝柏球果中所含挥发性物质的种类及其含量进行了分析测定。从急尖长苞冷杉球果中共检测到13种挥发性物质,其由10种单萜、1种酚、2种醇组成。并以ɑ-蒎烯、月桂烯、β-蒎烯和β-水芹烯4种化合物为优势组分,其中又以β-水芹烯的含量最高,且该成分在急尖长苞冷杉枝条和小果垂枝柏球果所含的挥发性物质中没有。急尖长苞冷杉枝条所含的挥发性物质由6种单萜、1种酚组成,且其酚的含量最高。小果垂枝柏球果所含的挥发性物质成分相对简单,由5种单萜组成,其优势成分为香桧烯和柠檬烯,而柠檬烯在急尖长苞冷杉球果所含的挥发性物质中未检测到。由此推测,在冷杉顶小卷蛾选择寄主植物及其危害的器官时,急尖长苞冷杉球果中所含的大量β-水芹烯挥发性物质对该虫起有引诱作用,而另两种器官所含的柠檬烯挥发性物质则对该虫起有驱避作用。 相似文献
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Zhang Jin-feng Li Hui Dong Jian-sheng Wang Jun-hui Key Laboratory for Genetics Breeding in Forest Trees Ornamental Plants Ministry of Education Beijing Forestry University Beijing P. R. China 《中国林学(英文版)》2005,7(1)
In order to obtain information on the genetic structure of Abies concolor and the genetic variation among 11 popula- tions introduced from America to China, allozyme analysis based on starch gel electrophoresis technology was used. 24 loci of 10 allozyme systems were mensurated, and the genetic structure and genetic diversity of the 11 populations of A. concolor evaluated. The results show that the genetic variation among is significant, and the genetic variation within A. concolor populations is more important. In contrast with other conifers, the variation of A. concolor is above the average level of conifers, and higher than the same level of Abies. The percentage of polymorphic loci (P) was 62.5%, the number of alleles per locus (A) 2.08, the number of ef- fective alleles per locus (Ae) was 1.37, the expected heterozygosity (H) 0.204, and the Shannon information index (I) 0.351 7. There is a short genetic distance (D=0.061) and a low gene flow (Nm=0.839 4) among the 11 introduced populations of A. concolor with high genetic variation. The genetic differentiation coefficient (Gst) was 0.229 5, which is higher than that of the mean in Abies or Pinus. 相似文献
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文章详细描述元宝山冷杉形态特征,分析了目前元宝山冷杉的生存环境、资源数量、生长与自然更新能力,指出实现有效保护所要面对的问题和应采取的措施。 相似文献
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《Scandinavian Journal of Forest Research》2012,27(5):489-499
The frost hardiness of non-juvenile Norway spruce [Picea abies (L.) Karst.] populations growing in northern Sweden (63°54' N) was monitored during 1996-1997. The investigated progenies originated from 12 natural populations and six seed orchards located between 58° N and 68° N in Sweden. Frost hardiness of needles was assessed by measuring chlorophyll fluorescence and electrolyte leakage after freezing. The loss of frost hardiness in 1-yr-old needles during spring occurred slightly earlier in populations originating north of 63°30' N than in those originating further south. Dehardening was slightly delayed in selected populations compared with natural populations of similar origin. The level of frost hardiness during autumn was higher in populations originating north of 63°30' N than in those originating south of this latitude, but there were no clear differences in frost hardiness between selected and natural populations of similar origin. The results are discussed in relation to climatic factors and inherent growth rhythms. 相似文献
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濒危植物急尖长苞冷杉种群结构及空间分布格局 总被引:1,自引:1,他引:1
以分布在西藏色季拉山的急尖长苞冷杉为研究对象,设置30m×30m样地15块,应用相邻格子法进行每木调查,从高度结构、基径结构、年龄结构以及空间分布格局方面分析了急尖长苞冷杉的种群特征。结果表明:在研究区,急尖长苞冷杉种群的高度结构、基径结构和年龄结构均表现为反"J"型,相关性也较明显,基径与年龄的关系为y=13.5640x0.7078(R2=0.9144);总体上,幼苗的后备储量特别大、死亡率也较高,但补充率大于死亡率,种群表现为稳定发展型。在不同尺度下,不同龄级(发育阶段)急尖长苞冷杉种群分布格局有差异。随着取样尺度的增大,各龄级植株的分布格局由聚集趋向均匀分布,聚集强度减弱,同一取样尺度下,龄级越大,聚集强度也越弱。研究结果可为该资源的管理及持续利用提供理论依据。 相似文献
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应用原子吸收光谱法测定了百山祖冷杉枝和针叶中K、Na、Cu、Ca、Zn、Fe、Mg、Mn 8种营养元素的含量,结果表明,百山祖冷杉枝和针叶中均含有所测的K、Cu、Ca、Zn、Fe、Mg、Mn等元素,但未检出Na元素;其含量为CaKMgZnFeMnCuNa。与大多数植物体正常生长发育的元素含量范围值相比较,百山祖冷杉枝和针叶中K含量分别为2 967.68~5 585.95、4 036.13~5 194.30 mg/kg,均低于临界值,针叶中Cu含量2.58~4.70 mg/kg,略低于一般植物水平,枝部Zn、Mn含量及针叶Mn含量则均处于较高水平。 相似文献