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1.
本文应用Greig-Smith邻接格子样方法取样和区组分析，对广西桂林石山次生灌丛的主要种群进行种间分布格局和种间相关性分析，结果表明：1、广西桂林石山次生灌丛四种主植物种群九龙藤（Bauhinia Championi Benth)、薄叶鼠李（Rhamnus Leptophyllas Schneid)、小果蔷薇（RosaCymosa Tratt)和竹叶椒（Zanthoxylum planispinum S.et)种群在次生灌丛群落中呈集群分布趋势，并且各种群的集群分布格局的聚块强度大小与取样面积大小有关。2、广西桂林石山次生灌丛的主要种群间性状类似的种群比较容易表现为负相关关系，反之，往往表现为正相关，或者相关关系复杂化。 相似文献
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采用相邻格子法取样的数据,应用方差/均值比的t检验法、负二项参数、扩散型指数、Cassie指标、丛生指标、平均拥挤指数和聚块性指数等方法,分析了天台山木荷种群在不同群落中的空间分布格局。结果表明:木荷种群在木荷纯林、常绿阔叶林中呈集群分布,而在针阔混交林中为集群趋向随机分布。其集群强度表现为常绿阔叶林最大,木荷纯林次之,针阔混交林最小。此外,还分大小级对木荷种群的分布格局进行了测定,从幼苗到中树,种群从集群分布到随机分布甚至均匀分布,集群强度逐渐降低,总体上种群呈扩散趋势。 相似文献
3.
四面山次生灌丛主要种群间的联结性研究 总被引：1，自引：0，他引：1
李裕红 《泉州师范学院学报》2001,19(2):63-67
基于方差分析、X∧2检验、Ochiai指数、Dice指数和Jaccard指数等系列技术，测定了重庆四面山次生灌丛12个主要种群间的总体相关性，各种对间联结显性和关联强度，结果表明：上述系列技术能有效地度量出多种对间的联结性，揭示出四面山次生灌丛群落中，除个别种对外，多数种群间的联结性不显，总体上趋于独立分布，这反映了次生灌丛群落处于演替前期的年轻性和不成熟性等特征。 相似文献
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重庆四面山次生灌丛的物种多样性特征 总被引：2，自引：0，他引：2
李裕红 《泉州师范学院学报》2000,(2)
通过拟合对数正态分布曲线描述四面山次生灌丛的种多度格局 ,并用多种公式计算该群落的物种多样性 ,通过比较与分析 ,得出结论 :1四面山次生灌丛群落的种多度关系符合对数正态分布模型 ,结合分布曲线指出在此群落中多度大的物种只有极少数 ,多数物种的多度都偏小 ,从而说明了次生灌丛群落的年轻性与不稳定性 ;2该群落的物种丰富度、均匀度和总多样性指数值都较低 ,揭示次生灌丛作为森林演替的初级群落其结构与组成部分较简单 ,功能还不完善 ,同时指出为提高森林覆盖率 ,有必要保护和发展次生灌丛 ,提高其多样性 相似文献
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以分布在天台山的木荷为研究对象,对本荷种群结构与分布格局进行了研究。木荷种群大小级结构除Q_1、Q_2外,其余均为Ⅰ级幼苗最多.Ⅱ级幼树次之,Ⅴ级大树最少。种群年龄结构为增长型,Q_1、Q_2种群年龄结构由增长型趋向稳定型。高度级结构以0-2m的个体最多,占总数的74.61％;2-4m的个体次之,占总数的9.72％;最高高度不超过22m。本荷整个种群分布格局呈集群分布。Ⅰ级幼苗、Ⅱ级幼树、Ⅲ级小树、Ⅳ级中树均呈集群分布.Ⅴ级大树有均匀分布的趋势。 相似文献
7.
用“空间序列代替时间变化”的方法,对浙江省天台山常绿阔叶林建群种甜槠的结构及动态进行了研究。结果表明:甜槠种群各样地大小级分布图的形状基本相似,种群的年龄结构为稳定型。甜槠种群高度级结构以0～2m的个体最多,占41.54％;2～4m的个体次之,占总数22.35％;大于10m共108株,占5.09％;最高高度达26m。甜槠种群密度随径级的增大而减少,密度与径级的相关模型为D=8.5178×10~4A~(-1.7497)。甜槠种群的分布格局呈集群分布。 相似文献
8.
为有效防治校园草坪杂草,以安徽科技学院草坪为例,采用踏查法和样方法对校园草坪杂草进行全面调查;测度杂草的植物区系、干重、高度、重要值、Simpson指数、Shannon-Weiner指数、均匀度指数和主要杂草的种群分布格局。结果表明,安徽科技学院草坪杂草种类共有35科,59属,75种。植物区系具有地带性特征,主要草坪杂草分布格局大多为集群分布,为有效防治草坪杂草提供科学依据。 相似文献
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四川大头茶(Gordonia acuminata)是我国亚热带西南地区常绿阔叶林优势种之一,材质好,生长快而又未被人注意的一种优良树种。四川大头茶种群在不同林分密度下的纯林中,其胸面积最大增长速度是:中密度>高密度>低密度,达到最大增长速度的径级范围都在18cm左右。种群密度随径级增大而减小。种群空间格局呈集群分布,从幼苗到乔木,其集群程度从大到小。 相似文献
10.
贵州雷公山秃杉种群分布格局的研究 总被引：3，自引：0，他引：3
采用相邻格子样方法取样数据,应用方差/均值比的t检验法、负二项参数、格林指数、Cassie指标、扩散指数、聚集度指标、平均拥挤度、聚块性指数等方法,研究了贵州雷公山秃杉种群的空间分布格局及其动态.结果表明:秃杉种群空间格局为聚集分布;从幼苗到大树,其聚集程度和规模逐渐减小,大树呈均匀分布. 相似文献
11.
The distribution of educated populations across age groups and the relative shares of population with different levels of attainment appears to be an important factor when it comes to explaining and predicting economic growth patterns both across developing countries and over time. A series of studies unveil the key role that complementing primary education with secondary schooling plays as a determinant of economic development. Here, we model the macroeconomic impact of the playing out of three different education-specific policy/investment scenarios (interacting with population dynamics). The model suggests that the Least Developed Countries would derive great economic benefits from increased investment in education, especially post-primary, as they move towards a post-MDG agenda. 相似文献
12.
Carin Berg 《Higher Education in Europe》1995,20(4):11-18
The organizers and sponsors of the Workshop are listed, and the names of some of the high‐level participants are cited. There were two full days of discussion including opening and closing sessions and seven working sessions, the topic of each onebeing cited. All aspects of the roles of national academies of sciences were considered and discussed. Among the important conclusions reached were that academies still had major scientific roles to play in their respective countries, that they should collaborate closely with universities with regard to research and the training of Ph.D.’s, that they should collaborate among themselves on an international basis, and that they should combat the phenomena of brain‐drain, on the one hand, and take steps, on the other hand, to make scientific careers attractive to young people. 相似文献
13.
John M. Hull 《Religious education (Chicago, Ill.)》2013,108(1):3-22
If we take seriously cultural or neo‐Marxian theories of periodicity, it becomes possible to identify educational problems that affect the formation of men and women as church leaders. These include the impact of money on contemporary spirituality, self‐deception, and other forms of coping with social injustice. Primary and secondary forms of false consciousness are described, and the article concludes with suggestions about curriculum and method in the training of Christian professionals 相似文献
14.
王清荣 《桂林师范高等专科学校学报》2004,18(4):29-32
实施以德治环境方略，必须既坚持把实现“人的全面发展”作为最终的价值取向，又把实现全体公民的社会主义生态伦理道德水准作为现阶段的价值取向；既坚持把人类的永续生存与发展的需要作为终极原则，又把合理满足当代人的生存与发展需要作为现阶段的基本原则；既坚持把是否有利于人类群体生存与发展作为善、恶的终极生态伦理评判标准，又把是否有利于促进社会主义三个文明建设发展作为善、恶的现阶段生态伦理评判标准；既把实现共产主义远大理想作为党的终极奋斗目标，又把实现全面建设小康社会作为党现阶段的奋斗目标。 相似文献
15.
Helen E. H. Russell B.D. 《Religious education (Chicago, Ill.)》2013,108(2):89-94
The official development of a curriculum of religious studies for secondary schools, based on a new Pennsylvania Law consistent with Supreme Court decisions, is of great significance. The process is described here with accuracy and humor 相似文献
16.
通过实验论证了伯醇、仲醇能进行银镜反应。报道了醇类在碱性条件下的银镜反应,这对某些特殊酸或特殊酮的定向合成会有十分重要的意义。 相似文献
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Reiko W. Sekiguchi 《Educational gerontology》2013,39(4-5):277-293
Japan is moving into an aging society at a greater speed than any other country in the world has ever experienced. As this speed is very rapid, the concept of life in the aged life‐cycle stage which has emerged has not been fully established yet; here the cultural lag phenomenon is acutely observed. Among many possible activities, however, learning activities will be expected to have increasing popularity among aged persons as a source of happiness and inspiration for the fulfillment of their lives. Since not only young persons, but also aged persons, are involved in learning activities, the concept expressed by the term education is changing into a broader one to include the transmitting of values, knowledge, and skills through secondary communication. 相似文献
18.
Impact analysis of natural disasters using interrelation of infrastructure and associated industries 总被引：1，自引：1，他引：0
Most serious natural disasters cause fatalities and injuries, and result in infrastructure damage, economic impacts, and social effects. With respect to the nature of impacts, it is important to understand the direct and indirect impacts of natural disasters on infrastructure and industries. In this paper, a holistic disaster impact analysis framework is presented to support more understanding of natural disaster events with respect to inter-relation of infrastructure and associated industries. Disaster impact mechanism and inter-relations based on critical function of industries derived from the extensive literature review and case studies. To develop the framework, service factor is chosen to measure the level of inter-relations and proper weights for each inter-relation between infrastructure and associated industries are obtained by surveying experts in the area of disaster mitigation, emergency organizations, and infrastructure management. This paper focuses on the impact analysis of hurricane disaster and the outcome can also be applied to other types of disasters. 相似文献
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本文对《地质学基础》地史部分的教材进行了分析,指出教材的特点,并对如何使学生学好该部分的内容,进行了探讨。 相似文献
20.
经济全球化对我国西部企业的影响,一方面生产国际化走向生产要素配置的全球化,经济增长中心走向多元化,贸易自由化,区域集团化;另一方面,西部企业起步晚,基础差,全球化的发展趋势给西部企业带来了极好机遇.西部企业如何抓住这一机遇,采取有效的营销对策,本文对此问题做了初步探讨. 相似文献