落叶松

Through the preliminary study on the management of the population of Athyrium multidentatum, we found that the community of artificial Larix gmelinii forest has a high value of usage. Planting the population of Athyrium multidentatum may make us to improve the level of intensive management, and through the test this method is available. The population of the spacing in the row of forty cm in the community of Betulla platyphylla forest and the population of the spacing in the row of eighty cm in the community of artificial Larix gmelinii forest have the largest hight, leafstalk diameter and less herb coverage. The foodstuff technology of ferns is backward and the products are less, so we must improve the study on the usage of forest ferns.

通过对猴腿蹄盖蕨种群经营措施的初步研究，我们得出落叶松人工林群落是一个极具开发价值的群落；人工移栽猴蹄盖蕨种群，可提高集约化管理程度，经过试验，方法可行；白桦林群落株距40cm的猴腿蹄盖蕨种群高度、叶柄直径均最大，且杂草盖度较小；落叶松人工林群落株距80cm的猴腿蹄盖蕨种群高度、叶柄直径均最大；蕨菜食品加工技术落后、工艺简单、产品单一，今后应加强研究。

Major tree species found here include conifers, such as Korean pine, larch and Olga Bay larch, and coniferous-broadleaf trees such as white birch, oak, willow, elm and Northeast China ash.

主要树种这里找到包括针叶树，如红松，落叶松和奥尔加湾落叶松，和针叶树，阔叶树，如白桦，柞木，柳树，榆树和东北灰烬。

The physical, mechanical and structural performances of Chinese larch plywood products manufactured using conventional technology are introduced. The technology of manufacturing larch plywood sheathing used for light wood-frame construction has been studied and developed.

介绍了我国常规工艺生产的落叶松结构胶合板产品的各项物理、力学和结构性能，研究开发了轻型木结构用落叶松胶合板覆板的生产技术。

Self-pollination was brought as the essential reason for causing emptied seeds by former researchers. Based on those studies, potassium antimonate and electron microscopy were used to study the calcium distribution of pollens in the micropylar canal of self-pollinated and cross-pollinated ovules and morphological changes in certain cells undergoing programmed cell death from pollination to fertilization, and observation of histo-chemical changes during microgametopyte development was performed by paraffin section.

前人研究认为自交是华北落叶松产生空粒的主要原因，本论文在此基础，运用焦锑酸钾沉淀法配合电镜观察研究了传粉后到受精前异交控制和自交辅助授粉胚珠珠孔道内花粉的钙分布情况，及此过程中细胞程序化死亡超微结构的变化，并通过石蜡切片研究了华北落叶松传粉后到受精前雌配子体发育过程及细胞内含物的变化，以研究在受精前胚珠内是否存在花粉识别与选择系统，探讨钙信号传导和花粉与胚珠相互作用及细胞程序化死亡的关系。

To study the molecular mechanism of Larix somatic embryogenesis, a differentially expressed cDNA library of Larix somatic embryo in the period of maturation was constructed using suppression subtractive hybridization. The cDNA from the cultures at the stage of somatic embryo maturation of embryogenic cell line Y35 of L. leptolepis L. princi-pis-rupprechtii was used as the tester and the cDNA from its subcultured callus was used as the driver. Eight hundreds ran-domly selected positive clones were sequenced, and 468 UniGenes were obtained finally.

为研究落叶松体细胞胚胎发生的分子机理，文章以日本落叶松华北落叶松杂种无性系胚性细胞系Y35体细胞胚成熟阶段培养物的cDNA为实验组，继代培养阶段胚性愈伤组织的cDNA为对照组，利用抑制性消减杂交技术(Suppression subtractive hybridization， SSH)构建了体细胞胚成熟阶段的差异表达基因文库。

To study the molecular mechanism of Larix somatic embryogenesis, a differentially expressed cDNA library of Larix somatic embryo in the period of maturation was constructed using suppression subtractive hybridization. The cDNA from the cultures at the stage of somatic embryo maturation of embryogenic cell line Y35 of L. leptolepis × L . princi-pis-rupprechtii was used as the tester and the cDNA from its subcultured callus was used as the driver. Eight hundreds ran-domly selected positive clones were sequenced, and 468 UniGenes were obtained finally.

为研究落叶松体细胞胚胎发生的分子机理，文章以日本落叶松×华北落叶松杂种无性系胚性细胞系Y35体细胞胚成熟阶段培养物的cDNA为实验组，继代培养阶段胚性愈伤组织的cDNA为对照组，利用抑制性消减杂交技术(Suppression subtractive hybridization， SSH)构建了体细胞胚成熟阶段的差异表达基因文库。

The paper is to research physiological differentiation and DNA polymorphism of MLP. The main result is as follows: 1.Investigating the Poplar Resistance: the difference of sensitivity is prominent.Other poplars are infected by Melampsora larici-populina in different degree, except that Populus deltoids and Populus deltoides×P.

本论文主要是对来自西北，华北，东北和西南等省的多种落叶松—杨栅锈菌进行同工酶分析以及DNA多态性研究，得出如下结论：(1)寄主抗病性调查：杨树各派树种对落叶松杨栅锈菌的感病性差异明显，除美洲黑杨和中绥12号外，所有的杨树品种都不同程度地感染了落叶松杨栅锈菌。

Through investigation on relationship beween larch pure crop needle cast condition and forest soil in county Yitong of province Jilin, getting conclusion: pure crop needle cast condition growing on white betonies is more serious than growing on deeply brown soil.

通过对吉林省伊通县落叶松人工纯林落叶病病情与林地土壤关系调查发现：生长在白浆土类土壤上的落叶松纯林病情明显重于生长在暗棕壤土类土壤上的落叶松纯林。

Based on the data of Larch in eastern region of Daxinganling,the single entry volume table of Larch is established by using artificial neural networks and regression analysis.

采用大兴安岭东部落叶松Larch的材料，分别运用人工神经网络和回归分析方法编制了落叶松的一元材积表，人工神经网络在拟合过程中以落叶松胸径作为输入向量，以单株材积作为输出向量，并选出既符合林木材积曲线分布规律，又具有较高拟合准确度的网络模型，其网络结构为1∶2∶1，网络对象名为Enet。

Dead branches or knots in different sizes of tree was studied and different branch development phases of growth,suppression,death and self-pruning was analyzed to evaluate the effect that knot size and distribution impact on timber quality.Branch and knot dynamic models were developed using stand and tree variables.Based on multipleunit stepwise regression method, the individual tree growth model was established using forest and crown factors as the variable. The best taper equation model of Larix olgensis was bucking data of 130 sample trees selected in the studied area.

本研究以不同年龄、不同密度及不同立地条件的落叶松人工林作为研究对象，基于19块标准地中95株标准木的树干解析、枝解析及节子剖析数据，揭示了不同林分条件下林木的枝条数量及在树冠内的空间分布格局、生长发育规律；研究了不同大小树木的死枝和节子大小及其变化规律，分析了枝条的生长、被压、寿命和自然整枝过程，评价了节子大小和分布对木材质量的影响；以林分变量、林木变量和着枝深度等为自变量建立枝条生长和节子大小的动态预测模型；选择林分因子和林木的树冠因子作为竞争因子，用多元逐步回归的方法建立落叶松人工林与距离无关的单木生长模型，并根据研究地区选取的130株造材样木数据，建立了落叶松人工林最佳削度方程。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。