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用最大树种数测度森林群落树种丰富度
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作者 杨瑷铭 惠刚盈 《林业科学研究》 CSCD 北大核心 2021年第6期168-173,共6页
[目的]试图给出确定森林群落树种丰富度的方法,解决物种丰富度测度问题,完善森林生物多样性研究的方法。[方法]采用Monod模型表达种-面积曲线,通过数学手段确定最小森林群落面积和最大树种数。[结果]用本研究提出的方法对不同气候带森... [目的]试图给出确定森林群落树种丰富度的方法,解决物种丰富度测度问题,完善森林生物多样性研究的方法。[方法]采用Monod模型表达种-面积曲线,通过数学手段确定最小森林群落面积和最大树种数。[结果]用本研究提出的方法对不同气候带森林物种丰富度进行测算,结果表明:热带森林群落具有更高的最大树种数和更大的群落最小面积,物种丰富度随气候带由热带到寒温带逐渐减少。[结论]用最大树种数能够确切表达不同气候带森林群落树种丰富度,克服了现有研究中直接把不同大小调查面积上的树种数量视为树种丰富度的弊端。 展开更多
关键词 群落最小面积 最大树种数 树种丰富度 生物多样性
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林分树种组成多样性指数的构建 被引量:3
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作者 朱锦迪 韦新良 +2 位作者 汤孟平 杨晶晶 张继艳 《浙江农林大学学报》 CAS CSCD 北大核心 2022年第2期262-271,共10页
【目的】构建数量化指标以定量表达林分树种组成特征,是精准经营管理森林的技术基础。【方法】应用生物多样性理论,根据树种组成的特性和经营管理要求,构建了林分树种组成多样性指数(I_(SCD))。采用“十分法”,分析了不同树种数下指数... 【目的】构建数量化指标以定量表达林分树种组成特征,是精准经营管理森林的技术基础。【方法】应用生物多样性理论,根据树种组成的特性和经营管理要求,构建了林分树种组成多样性指数(I_(SCD))。采用“十分法”,分析了不同树种数下指数的变化规律及基本特性。以国家森林资源连续清查中浙江省322个针阔混交林样地为应用对象,对I_(SCD)与现有的α多样性指数进行了对比分析。【结果】I_(SCD)涵盖了林分中树种数、树种相对多度和树种蓄积比例等信息,突出体现树种数的同时,充分表达了树种组成的均匀性与混交程度。I_(SCD)可完整、独立和有效地表达树种组成的变化特性。与α多样性指数相比,I_(SCD)提高了对树种数判别的分异性和灵敏性,可严密地评价树种结构的均匀度和混交度,合理有效地反映树种多样性。【结论】与α多样性指数相比,构建数量化指标能更细致、全面、有针对性地定量化表征林分树种组成多样性,解决了低丰富度高均匀度、高丰富度低均匀度等不同林分树种组成类型难于有效区分的难题。 展开更多
关键词 林分 树种组成多样性指(I_(SCD)) 多样性指 树种数 均匀度
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基于4株相邻木关系的林分空间结构多样性测度方法研究
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作者 惠刚盈 赵中华 +4 位作者 胡艳波 张岗岗 张弓乔 程世平 卢彦磊 《北京林业大学学报》 CAS CSCD 北大核心 2023年第7期18-26,共9页
【目的】深入剖析林分空间结构参数四元分布的生态意义,构筑基于相邻木关系的林分空间结构多样性综合评价指数,为制订有的放矢的森林结构调整策略提供理论依据。【方法】基于生物多样性概念,以参照树与其最近的4株相邻木组成的结构单元... 【目的】深入剖析林分空间结构参数四元分布的生态意义,构筑基于相邻木关系的林分空间结构多样性综合评价指数,为制订有的放矢的森林结构调整策略提供理论依据。【方法】基于生物多样性概念,以参照树与其最近的4株相邻木组成的结构单元为对象,有机整合结构参数角尺度、混交度、大小比数和密集度的四元分布及结构单元树种数和林层数,运用遗传绝对距离公式、自然对数分别表达结构单元类型均匀性和丰富度,构造表达林分空间结构多样性测度指数,并运用长期定位监测样地数据进行验证。【结果】运用本研究提出的林分空间结构多样性指数(D_(FS))对处于不同气候带或不同起源的森林类型的空间结构多样性测度表明,锐齿栎天然林的D_(FS)值(0.854)与阔叶红松林的D_(FS)值(0.852)几乎相等,二者具有相似的空间结构多样性。侧柏人工林结构参数四元分布类型较多,高于锐齿栎天然林和红松阔叶林,但其空间结构多样性为3个林分类型中最低的(D_(FS)=0.382),主要原因是其垂直结构(D_(FSv)=0.369)和水平结构(D_(FSh)=0.562)多样性方面都比两类天然林低。结构单元中的平均树种数表现为天然林高于人工林,锐齿栎天然林为4.23,阔叶红松天然林为4.09,而侧柏人工林则为1.98,结构单元树种数能充分体现结构单元树种丰富程度。【结论】林分空间结构参数四元分布、结构单元树种数和林层数3者的有机整合是构造有效的林分空间结构多样性指数的基石。基于生物多样性概念提出的林分空间结构多样性指数D_(FS),既是对结构参数四元分布合适的量化表达,也是对结构参数四元分布生态意义恰当的诠释,更是对林分空间结构多样性的科学综合评价,能够测度出不同林分类型林分空间结构多样性的差异。 展开更多
关键词 林分空间结构 结构参N元分布 结构单元树种数 结构单元林层 林分空间结构多样性
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Establishment and Share of Tea Germplasm Database of Yunnan Province 被引量:2
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作者 蒋会兵 矣兵 王平盛 《Agricultural Science & Technology》 CAS 2011年第12期1966-1971,共6页
[Objective] The paper was to establish tea germplasm database of Yunnan Province,and promote sharing of the tea germplasm resources.[Method] Eight hundred and thirty copies of tea germplasm resources of Yunnan Provinc... [Objective] The paper was to establish tea germplasm database of Yunnan Province,and promote sharing of the tea germplasm resources.[Method] Eight hundred and thirty copies of tea germplasm resources of Yunnan Province were first systematically documented by using Access database software,the generic description of 631 tea resources and characteristic description of 300 tea resources were submitted for e-platform,then linked with the national e-platform for natural scientific and technological resources,and the tea germplasm database of Yunnan Province was established.[Result] Based on the conservation and utilization status of tea germplam resources,the sharing and utilization framework of tea germplam resources was presented.Many problems and suggestion about tea germplasm resources in the process of conservation,documentation concordance and sharing were pointed out.For example,conservation areas were separated and system was not completed;the main traits assessment and identification researching work had not completely accomplished and sharing was inefficient.[Conclusion] The paper laid foundation for standardized,digitized and information-based management of tea germplasm resources. 展开更多
关键词 TEA Germplasm resources DATABASE SHARE
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Living characteristics of rare and endangered species Davidia involucrata 被引量:5
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作者 吴钢 韩单恒 +3 位作者 王宏昌 罗跃初 邓红兵 赵景柱 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第1期39-44,J002,共7页
Dovetree (Davidia involucrate), one of the first-class protective plants in China, is a relic species of paleotropical kingdom in Tertiary period, belonging toDavidiaceae with a single genus. In recent years, the incr... Dovetree (Davidia involucrate), one of the first-class protective plants in China, is a relic species of paleotropical kingdom in Tertiary period, belonging toDavidiaceae with a single genus. In recent years, the increase of regional developing projects has led to a sharp decrease of this ancient and rare plant in naturally distributed habitats and natural population. In this paper, the biological and ecological characteristics of Dovetree were described, and the geographically distributed condition of this species in different geologic periods as well as the major reasons for dynamic changes of its population were systematically analyzed in accordance with field researches and references. The investigations conducted in different years by setting up standard sample plots showed that the population number of Dovetree increased yearly in the areas without human interference but decreased yearly in the areas with human interference. With the increase of population density and human activities decreased as the logarithmic curve:Y=?100.7ln(x)+178.09, and it has turned from a dominant population into an endangered population. Based on the former and present studies on Dovetree, some protection strategies were put foreword for protecting this ancient and rare species. Keywords Davidia involucrate - Dovetree - Geographical Distribution - Biological Characteristics - Protection Policy CLC number S718.4 Document code A Article ID 1007-662X(2004)01-0039-06 Foundation Item: This research was coordinated by the National Natural Science Foundation of China (No. 39970591)Biography: Wu Gang (1965-), Male, Professor in Key Laboratory of Systems Ecology, Research Center for Eco Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.Responsible editor: Chai Ruihai 展开更多
关键词 Davidia involucrate Dovetree Geographical Distribution Biological Characteristics Protection Policy
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Variability of leaf functional traits of invasive tree Rhus typhina L. in North China 被引量:4
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作者 WEI Mei WANG Shu +3 位作者 WU Bing-de JIANG Kun ZHOU Jia-wei WANG Cong-yan 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第1期155-163,共9页
Functional traits, specifically leaf functional traits, are core-topics to explore importance to the invasion success of invasive plant species. This study aims to address the differences in leaf functional traits and... Functional traits, specifically leaf functional traits, are core-topics to explore importance to the invasion success of invasive plant species. This study aims to address the differences in leaf functional traits and their corresponding variability of the invasive tree staghorn sumac Rhus typhina L. with different invasion success, including lower and higher invasion success, in two climatic regions in North China, including a warm temperate region and a cold temperate region. No significant differences were found for leaf functional traits of staghorn sumac across different invasion success. However, the variability of leaf chlorophyll and nitrogen concentrations of staghorn sumac under higher invasion success were approximately 66.023% and 68.615% higher than those under lower invasion success, respectively. The leaf chlorophyll and nitrogen concentrations of staghorn sumac in the warm temperate region were approximately 18.432% and 16.337% higher than those in cold temperate region, respectively. The variability of specific leaf area of staghorn sumac in warm temperate region was approximately 59.802% higher than that in cold temperate region. Accordingly, leaf chlorophyll and N concentrations as well as specific leaf area of staghorn sumac and their corresponding variability may play an essential role in shaping ecological success of studied invader along a climatic gradient. 展开更多
关键词 climatic region invasive tree coefficient of variation VARIABILITY specific leaf area Rhus typhina L.
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Effect of the Variety of Fig Tree on Some Biological Parameters of Ceratitis capitata Wied, 1824 (Diptera: Trypetidae) in Some Orchards in the Kabylie
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作者 Sadoudi-Ali Ahmed Djamila Nabila Rezoug +1 位作者 Ferroudja Saiki Noreddine Soltani 《Journal of Life Sciences》 2012年第3期312-319,共8页
The Mediterranean fruit fly, Ceratitis capitata Wied. (1824) is one of the most important pest that can infest orchards if its spread is not controlled. Among the preventive measures recommended in the fight against... The Mediterranean fruit fly, Ceratitis capitata Wied. (1824) is one of the most important pest that can infest orchards if its spread is not controlled. Among the preventive measures recommended in the fight against this pest, we are interested in looking for varieties that are less favorable to the development of this pest among different varieties of fig trees in our region. The biological parameters of the fruit fly which were followed in this study are duration of pupation, rate of emergence, sex ratio and longevity of males and females. The results show that these parameters vary depending on the variety of fruit. 展开更多
关键词 Ceratitis capitata varieties of figs PUPAE PUPATION emergence sex ratio longevity.
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Tree and shrub species preferences and planting materials used by sub-religious communities in the village groves of floodplain area of Bangladesh
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作者 Md.Danesh Miah Mohammad Moshiur Rahman 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第1期55-60,J003,共7页
An exploratory study of the traditional homestead forest of two different religious groups (Hindu and Muslim) in one selected floodplain area of Bangladesh was conducted over a period of six months from January to Jun... An exploratory study of the traditional homestead forest of two different religious groups (Hindu and Muslim) in one selected floodplain area of Bangladesh was conducted over a period of six months from January to June 2002. The species' (both tree and shrub) preferences, similarities, use and sources of planting materials, spacing and location of species in the homesteads of both Hindu and Muslim communities were studied. It was found thatMangifera indica as tree species andOcimum sanctum as shrub species were the best preferred species of the Hindu community.Artocarpus heterophyllus as tree species andLawsonia inermis as shrub species were found best preferred by the Muslim community. Floristic similarities between the two groups were found 86.57% in tree species and 78.48% in shrub species. Both seed and seedlings of tree and shrub species as planting materials were used by the highest percentage of both the religious communities. For tree species, homegarden was reported to be the highest source (39%) and for shrub species, nature was the highest source (40%), which was found in the Hindu community. Key words Species preferences - Species similarity - Planting materials - Hindu - Muslim - Homestead forests - Floodplain area - Bangladesh CLC number S72 Document code A Biography: Md. Danesh Miah (1971): male, Assistant Professor in the Institute of Forestry and Environmental Sciences, University of Chittagong, Chittagong 4331, Bangladesh.Responsible editor: Chai Ruihai 展开更多
关键词 Species preferences Species similarity Planting materials HINDU Muslim Homestead forests Floodplain area BANGLADESH
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The BPP program for species tree estimation and species delimitation 被引量:17
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作者 Ziheng YANG 《Current Zoology》 SCIE CAS CSCD 2015年第5期854-865,共12页
This paper provides an overview and a tutorial of the BPP program, which is a Bayesian MCMC program for analyzing multi-locus genomic sequence data under the multispecies coalescent model. An example dataset of five n... This paper provides an overview and a tutorial of the BPP program, which is a Bayesian MCMC program for analyzing multi-locus genomic sequence data under the multispecies coalescent model. An example dataset of five nuclear loci from the East Asian brown frogs is used to illustrate four different analyses, including estimation of species divergence times and population size parameters under the multispecies coalescent model on a fixed species phylogeny (A00), species tree estimation when the assignment and species delimitation are fixed (A01), species delimitation using a fixed guide tree (A10), and joint species delimitation and species-tree estimation or unguided species delimitation (A11). For the joint analysis (A11), two new priors are introduced, which assign uniform probabilities for the different numbers of delimited species, which may be useful when assignment, species delimitation, and species phylogeny are all inferred in one joint analysis. The paper ends with a discussion of the assumptions, the strengths and weaknesses of the BPP analysis [Current Zoology 61 (5): 854-865, 2015]. 展开更多
关键词 BPP MCMC Multispecies coalescent Species delimitation Species tree
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Application of probability distribution in order to fit the diameter and natural and man-made height of oak species in two stands in Hyrcanian forests
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作者 Farah Mohammadi Mir Mozaffar Fallahchai Seyed Armin Hashemi 《International Journal of Biomathematics》 2016年第3期293-301,共9页
In order to study the fitting of some characteristics like low diameter at breast height (DBH), the height and height to the beginning of crown of the Oak species in two man-made and natural forests of this species ... In order to study the fitting of some characteristics like low diameter at breast height (DBH), the height and height to the beginning of crown of the Oak species in two man-made and natural forests of this species in north of Guilan's forests, Tooshi and Radarposhte forests were selected. A 100% inventory was done on a one-hectare sample plot in Tooshi man-made forests and on a two-hectare sample plot in Radarposhte natural forests. The results from this study showed that, in order to fit the diameter and the height of the Oak trees in man-made stands, Johnson's SB and normal statistical distributions have more capabilities and the three-parameter gamma and the three- parameter Weibull distributions are appropriate for diameters and heights of the natural Oak trees in Radarposhte forest, respectively. 展开更多
关键词 Fitting DIAMETER HEIGHT OAK Hyrcanian forests.
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Genetic diversity of oil-tea camellia germplasms revealed by ISSR analysis 被引量:1
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作者 Lan-Ying Zhou Xiang-Nan Wang +2 位作者 Li-Ping Wang Yong-Zhong Chen Xiao-Cheng Jiang 《International Journal of Biomathematics》 2015年第5期331-354,共24页
Genetic diversity of 51 oil-tea camellia germplasms was analyzed using the optimized inter-simple sequence repeat (ISSR)-PCR reaction system with 22 primers screened from a set of 100 ISSR primers. The results showe... Genetic diversity of 51 oil-tea camellia germplasms was analyzed using the optimized inter-simple sequence repeat (ISSR)-PCR reaction system with 22 primers screened from a set of 100 ISSR primers. The results showed that 493 discernible loci with distinct elec- trophoretic bands were obtained, of which, 478 loci (96.78%) were polymorphic. This indicated that oil-tea germplasms possess abundant genetic diversities. By clustering analysis performed using softwares of NTSYS 2.10 and Winboot, 51 oil-tea germplasms were divided into two groups: Group I had 48 lines of Camellia oleifera Abel, while Group II had three C. oleifera Abel related species and their similarity coefficient was 0.62. Group I was further divided into Group I-1 and Group I-2, and their similarity coefficient (Gs) was 0.634. All members of Group I-1 originated from Hunan Province, while Group I-2 included the rest of Hunan lines and those originated from other regions of China. Analyzed by software POPGENE 1.32, the Shannon's information index (I*) of genetic polymorphism was 0.3852, the genetic diversity among different region popula- tions (Ht) was 0.2537, the genetic diversity within populations (Hs) was 0.15545, the dif- ferentiation coefficient of genetic diversity among populations (Gst) was 0.3967, and the gene flow among populations (Nm*) was 0.8262. The Nei's genetic distances between the Hunan population and the populations originated from other regions of China implied that geographic isolation strongly influenced genetic differentiation among populations. Meanwhile, seedling rootstock grafting and high grafting for tree crown produced genetic variations among clonal offsprings. 展开更多
关键词 Oil-tea camellia ISSR genetic diversity grafting.
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