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1.
以琅琊山森林群落的10个样方的调查资料为基础,采用物种丰富度、优势度指数和物种多样性指数等指标对琅琊山森林群落草本层物种多样性进行分析.结果表明,样方草本层中各物种间重要值差异较大的,其优势度指数越大;而物种多样性指数则随样方海拔高度的升高而降低.  相似文献   

2.
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  
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   

3.
宏门冲蝶类多样性研究初报   总被引:8,自引:0,他引:8  
于 2 0 0 2年 9月 2 5~ 2 9日对湖南省通道县宏门冲蝶类多样性进行了初步研究 结果表明 :宏门冲蝶类群落物种丰富 在样地内共采集与记录蝴蝶 2 4 3号 ,隶属 7科 ,2 8属 ,2 6种 主要成分是 :粉蝶科 (黄粉蝶属 ) ,凤蝶科 (凤蝶属 ) ,蛱蝶科 (环蛱蝶属、眼蛱蝶属 ) ,眼蝶科 (眉眼蝶属、矍眼蝶属、黛眼蝶属 ) 各生境多样性指数、种类丰富度是沿溪农田 >山地灌丛 >森林  相似文献   

4.
对由马尾松演替成的次生林的种类组成、物种多样性和物种重要值进行调查分析。初步探讨此群落乔木树种的演替趋势,该林分群落多样性Simpon指数和shannon——Wiener指数分别达0.8935和2.5036,显示该群落是相对稳定性较大的群落。群落物种多样性丰富;群落重要值分析表明马尾松和青冈是该群落的主要优势种。群落演替趋势说明,种质资源和土壤条件是影响该林分演替趋向的主要因素。  相似文献   

5.
河北省临城小天池种子植物植被类型及群落特征经初步调查研究和积累资料的统计表明,有裸子植物2科2种、被子植物45目84科419种;分析了森林群落的区系类型及群落的物种多样性.  相似文献   

6.
广东英德石门台自然保护区山顶矮林物种多样性分析   总被引:1,自引:0,他引:1  
利用Shannon-Wiener指数、物种均匀度、物种丰富度、生态优势度及物种多度分布研究了广东英德石门台自然保护区山顶矮林的物种多样性。结果表明:山顶矮林乔木层、灌木层、草本层和藤本植物的Shannon-Wiener指数的变化范围分别为1.213~3.338、1.116~2.843、0.291~2.278和0.101~1.951;物种均匀度,表现为乔木层>灌木层>藤本植物>草本层。按垂直结构层次的生态优势度顺序为草本层>藤本植物>灌木层>乔木层。各样地乔木第一亚层的多样性指数、物种数和株数均低于第二亚层。山顶矮林的乔木层、灌木层、草本层和藤本植物的多度分布都适合于对数级数分布,说明山顶矮林富集种少、稀疏种多。  相似文献   

7.
通过样方法实地调查梅州市国有水口林场,分析其人工林群落结构特点以及物种多样性现状,结果表明:该林场维管植物有67种,隶属35科,60属,其中乔木层物种11种,灌木层物种27种,草本层物种51种.群落植物区系具明显的热带分布性质,属于典型的南亚热带常绿阔叶林,物种组成以双子叶植物为主,占比近66%,优势种多为人工种植的黑木相思、马尾松等.其中灌木层的均匀度高于乔木层、草本层,草本层的Margalef指数和Shannon-Wiener多样性指数均高于乔木层、灌木层,乔木层的Simpson指数最低为0.788 7,草本层的Shannon-Wiener多样性指数最高为2.789 9.加强封山育林,适当地补种一些乡土植物,尤其是乔木种类,以增加植物多样性,可促进植被恢复.  相似文献   

8.
本文对生态系统水平的多样性进行了综合报道.其主要研究内客涉及(1)物种及高级分类单位的多样性;(2)生物多样性与群落结构;(3)群落的营养多样性;(4)群落和生态系统的复杂性;(5)多样性与稳定性和生产力。  相似文献   

9.
对玉米田昆虫群落进行了系统调查,通过从群落生态学的角度进行分析,运用群落的重要指标相对多度、物种丰富度(S)、优势度(d)、多样性指数(H~1)、生态优势度(C)进行分析研究,基本探清了玉米田昆虫群落的组成及其变动情况.经调查得知玉米田昆虫群落由31个种组成,分属于11个目、22个科.昆虫数量由大到小依次为鳞翅目、鞘翅目、半翅目、直翅目、双翅目、同翅目、脉翅目、膜翅目、缨翅目、蜘蛛目、蜱螨目.在整个调查期间都处于优势地位的是玉米蚜Rhopalcsiphum maidis、异色瓢虫Harmonia axyridis和七星瓢虫Coccinellaseptempunctata.根据玉米田昆虫群落的组成与结构、发生发展特点,为农业生产提供指导,便于合理安排农业生产和进行农业害虫防治.  相似文献   

10.
井冈山自然保护区栲树群落研究   总被引:1,自引:0,他引:1  
以栲树群落8个样地调查资料为基础,对该群落的物种组成、区系成分和物种多样性进行了统计和分析,结果表明:栲树并落中有维管植物51科67属98种(含变种);属的地理成分复杂,以热带成分为主,温带成分只占较少比例;乔木层、灌木层和草本层的各项物种多样性指标在群落各样地间均有一定的差异;在群落垂直结构中,灌木层的多样性指数最大,乔木层次之,草本层最小。  相似文献   

11.
生物多样性保护与人类的关系   总被引:1,自引:0,他引:1  
介绍了生物多样性的三个层次,即生态系统多样性、物种多样性和遗传多样性,及其主要含义、主要研究内容.并简要讨论了生物多样性保护研究的重要性,以引起人们对日益恶化的环境给予重视,共同保护我们的生存环境,保护生物多样性.  相似文献   

12.
Increasingly the social, educational, cultural,linguistic, religious and racial diversity ofSouth African society is finding expressionwithin South African institutions of highereducation. Consequently, ``diversity'',``diversity issues'' and ``diversification'', havebecome part of the education debate and policy,and pose new challenges to South Africantertiary institutions. Most institutions areattempting to respond to these challengeswithin the context of a transformation processwhich impacts on every aspect of academic lifefrom student access and support, outreachprogrammes, staff recruitment and retention, toacademic programme development, research,scholarship and the social and learningenvironment on campus. This paper looks at howSouth African higher education institutionshave met these challenges. It highlights howthe ideas, initiatives or practices arounddiversity have been appropriated and made partof the mainstream intellectual and academicdiscourses. It also investigates the social andepistemological conditions of possibility formeaningful scholarship and curriculum practicesin addressing the challenges posed by socialdiversity on campuses. More specific questionsin this regard include: What counts asknowledge in diversity scholarship? Whoproduces and disseminates it? Who accesses itor utilises it? What is its space in thecurricula?  相似文献   

13.
Third-country faculty are faced with significant challenges interacting with university students who come from different socio-cultural backgrounds and have different expectations regarding faculty’s role, behavior, and leadership style. This paper compares diversity practices and action options that can facilitate or hinder the integration of third-country faculty across five universities established in an equal number of countries. The proportion of third-country faculty in American universities abroad is also used to provide a measure of diversity. Notwithstanding recent trends pointing to the internationalization of higher education universities have yet to develop an appropriate institutional mentality along with supporting diversity policies that would help them gain global efficiencies by hiring qualified international faculty. This may have serious implications for organizational effectiveness with respect to resource acquisition and even the long-term survival of the organization. The author is Associate Professor and Chair in the Department of Management and E-Business in the School of Business, the American University in Dubai.  相似文献   

14.
后现代是个价值多元时代,后现代主义艺术也具有多元性特征:不确定性、零乱性、非原则化、反讽性、参与性、无深度等等。  相似文献   

15.
生物多样性是人类赖以生存的基础 ,由于人为因素致使自然环境加速破坏 ,物种和种群日趋减少 .为保护生物多样性 ,减少人为因素对环境的破坏 ,我们必须采取一系列有效措施 .  相似文献   

16.
This paper draws upon interviews with eight headteachers in ‘Northern LEA’, and examines (a) how the heads perceived their role in relation to the current period of rapid educational change, and (b) how they sought to cope with the increasingly difficult demands which they faced. The consequences of the current situation are considered in relation to a qualitative understanding of ‘high performance’ which recognises the situational complexity of the school as an organisation.

The heads made use of many sources of support; the most important were a network of informal contacts with other headteachers and an increase in the involvement of senior management team colleagues in the stresses and responsibilities of management. The paper concludes that despite the efforts of the heads themselves, the consequences of resource cuts and the Education Reform Act 1988 are likely to make the achievement and management of high performance increasingly difficult.  相似文献   

17.
通过对石斛茎部内生真菌进行分离鉴定,将这些菌分属3亚门,5纲,8目,10科,12属,其中子囊菌和半知菌为优势菌。  相似文献   

18.
教育学的统一性与多样性在现代文化发展中始终是现实统一的。统一性使教育学有它皇身的完整体系,多样性使教育学体系更加丰富和完善,使教育学能够接纳和吸收不同的文化及思菽篓二性和多样性是教育学的双重属性,它们都揭示了教育学的学科属性及教育学理论体系建构、发展的趋努。将两者有机的统一起来是教育学应具有的学科立场。  相似文献   

19.
从理论上认清、实践上处理好"一元"与"多样"的辩证关系是做好意识形态工作的必然要求。正确认识和处理指导思想一元化与思想文化的多样性的关系,必须始终坚持马克思主义的一元指导,必须加强党在意识形态领域的执政能力,必须尊重差异、包容多样,坚持以社会主义核心价值体系引领社会思潮,必须反对指导思想的"多元论"。  相似文献   

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