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双语推荐：群落结构

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物种多样性是群落功能复杂性和稳定性的重要量度指标,人为干扰对森林群落的影响可以通过群落结构和物种多样性的变化而直接显现,不同干扰强度下的森林群落结构和物种多样性特征不同。采用典型样地法,对比研究两种人为干扰强度(干扰强和弱)对江油地区的马尾松(Pinus massoniana)人工林群落的物种组成、群落结构和物种多样性的影响,采用物种丰富度指数D值、Shannon-wienner指数H值、Simpson优势度指数H′值和均匀度指数Jsw值来综合衡量群落的物种多样性水平。结果表明,(1)在总面积3200 m2的8个样地中记录到124个物种,隶属于105属56科,干扰强的群落各层次物种数均低于干扰弱的群落。(2)不同强度人为干扰下马尾松人工林的群落结构不同,干扰弱的群落径级结构呈近正态分布,在径级Ⅵ(7 cm≤d9 cm)处出现数量的峰值26株,群落结构较稳定;干扰强的群落径级结构不呈正态分布,在径级Ⅶ(13 cm≤d15 cm)处出现峰值43株。干扰弱和干扰强的群落高度级结构与其径级结构具有相似性,干扰弱的群落的个体主要集中在低中高度级(3≤H17);干扰强的群落的个体数在各高度级分布不均匀,主要分布在中高高度级(H≥13);干扰强的群落的个体数在各径级和高度级分布相对不均匀,群落结构趋于不稳定。(3)
Over the last century, human disturbance plays an important role in the change of global climate and environment and consequently, the loss of global species diversity. Unsustainable use of forest resources is causing dramatic changes in the forest communities and poses a serious threat to biodiversity worldwide. Plant species diversity is an index reflecting the complexity and stability of forest community function. The effect of human disturbance on forest community can be directly reflected by the change of community structure and diversity. We hypothesize that community structure and plant species diversity varies with the different densities of human disturbance. In order to investigate the influences of different disturbances (slight disturbance and severe disturbance) on the characteristics of species composition and diversity ofPinus massoniana plantation in Jiangyou district, Sichuan Province, a field investigation was conducted. The species richness indexD, Shannon-wienner in

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以高度级为参考坐标,应用衡量群落结构及其动态的失稳率和群落垂直空间的分享度等指标对南方林区4个不同套种模式马尾松群落高度级结构特征及其动态进行分析.结果表明:套种模式1、套种模式2和套种模式4群落高度级内个体数量分布呈先降低后升高的U型结构,物种数量和物种个体数量在中等高度级出现低频区域,群落动态表现为高等高度级衰退趋势;套种模式3群落呈基部大、顶层小的塔形结构,物种数量和物种个体数量主要集中在低等高度级,反映出该群落具有极强的增长特性.不同套种模式群落分享度均比较低,反映出南方林区马尾松人工林群落物种数量相对单一的弊端.
The highness class structure of Pinus massoniana forest with different intercropping modes in southern forest was measured and analyzed. When the community of highness class was regarded as coordinate axis, a series of targets, e. g. lost stable rate of individual number between highness classes and dynamics of the community. The results indicated that the individual number and species number of the community first reduced then decreased as U-type structure with highness classes raised in intercropping modes 1 ,2 and 4 . Low-frequency region was in medium height class, showed that community dynamics declining trend in higher class. The individual number and species number of the community in intercropping modes 3 mainly concentrated in low height level as a pyramid structure, reflect those communities has a very strong growth characteristics. Species sharing degree were lower in different intercropping modes community,which reflected a malpractice that number of species is relatively s

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选取晋中市榆次区乌金山群落分布比较集中的地段,设计11个样地,采用样方法进行调查研究.分析了乌金山森林群落的种类组成、群落外貌、垂直结构和水平结构等群落学特征,并对该群落的环境概况进行分析,计测了不同地段上群落的频度、盖度指标和不同层次上的丰富度指数、均匀度指数、多样性指数.结果表明：在乌金山海拔950 m-1450 m之间,群落分为乔、灌、草3个层次,乔木层为油松单优组成,外貌特征上以地面芽植物为主.其林下物种多样性指数与海拔高度有密切的关系.随着海拔的升高,森林群落的丰富度指数呈上升趋势,均匀度指数呈平缓下降的趋势,多样性指数变化趋势不明显;乌金山植物群落的物种多样性指数和丰富度指数明显受群落类型和群落结构的影响,群落结构越复杂,丰富度指数和物种多样性指数越大,均匀度指数越小.
The age class structure of Pinus tabulae formis population in Wujin Mountain was investigated on the basis of the population life tables and survival analysis theory by the technique of smoothing. The results show that the age class structure of pine species is stable, but the seedlings, saplings are relatively less, and that the mortality of pine species curve appears two peaks——one age class in the first stage 5th、6th and 8th, the other age class in the 12th stage; and survival curve takes on Deevey-Ⅱtype.

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以赤水河上游森林群落为研究对象，采用PCA和RDA排序分析，筛选植物群落地上部分组成及结构的持水功能指标，构建了植物群落持水功能评价指标体系，并采用指标加权乘积法评价赤水河上游27块森林群落样地的持水能力。结果表明，灌草、灌木、灌丛阶段群落及乔林阶段中竹林为低持水群落，次顶极群落和多数乔林群落为中持水群落，仅乔林阶段中巴豆＋柏木群落中2块样地为高持水群落。导致群落持水功能差异的主因是持水结构组成不同。
The upstream plant community in Chishui River was chosen as research object to build the evaluation in-dex system of plant community water-holding function by using PCA and RDA sort-based analysis for screening water holding function index of above-ground structure of plant communities.Based on the assessment of water holding a-bility of 27 samples by the index weighted product , the results showed that differences in the structure of plant com-munity was the major cause for different water holding levels.In all analyzed plant communities, only croton, with combination of cypress presented higher water-holding ability, and then were the community of shrub, climax and timber forest, while the shrub-grass, brush stage, as well as bamboo standing in tree layer were the lowest.

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以肉食性南方大口鲇（Silurus soldatovi meridonalis Chen）为对象,研究采用PCR-DGGE指纹技术对其仔稚鱼胃肠道分化过程及细菌群落结构进行了对比分析,进而探讨了细菌群落与胃肠道分化的关系。消化道外部形态和胃肠切片显示13日龄样品起,胃肠在结构上出现较大的分化。DGGE分析结果显示胃肠道细菌群落的分化始于18日龄：从18日龄样品起,肠内细菌群落明显开始分化,但在随后的18—33日龄期间细菌群落结构相对稳定,而胃内细菌群落则一直处于动态变化中。这说明,南方大口鲇仔稚鱼的个体发育过程中,随着胃肠在组织结构上的分化,其消化道细菌群落结构也出现了明显分化,并且胃和肠内细菌群落结构的分化在时间上存在差异。该研究结果将为深入研究胃和肠内细菌群落的功能差异提供基础资料。
To explore the potential relationship between differentiation of gastrointestinal tract and the gastrointestinal microbiota colonization, polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) was applied to analyze the gastrointestinal microbiota alteration of Silurus soldatovi meridonalis Chen with the differentiation of gas-trointestinal tract. The differentiation of the intestinal microbiota started from 18-day samples and kept relatively stable in the following 23-, 28- and 33-day samples. However, the differentiation of the stomach microbiota was in dynamic variation process during the experiment. Morphological observation and histological slices of the gastrointestinal tract suggested a significant differentiation started at the developmental stage of 13-day. It indicated that with the differen-tiation of digestive system, the differentiations of bacteria community structures of both stomach and gut were different in spatiotempord.

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群落物种共存机制是生态学研究的重要论题。共存物种的生态和进化相似性是用于验证群落构建机制的关键信息之一,生态学家常用系统发育和基于功能性状的方法间接或直接估算相似性,从而揭示驱动群落构建的主要生态学过程。系统发育分析方法和基于功能性状的方法均能检验生境过滤和竞争排斥过程在群落构建中的作用,并为解决生态位理论和中性理论之争提供新的视角。根据现代物种共存理论,在不同的功能性状进化模式下,不同生态过程构建的群落功能结构和系统发育结构可能不同,聚集的群落系统发育结构可能在性状进化保守的情况下由生境过滤过程构建,也有可能在性状趋同进化的情况下由竞争排斥过程构建而成,因此检验功能性状系统发育信号对于推断群落构建机制显得十分必要,联合系统发育和功能性状的研究将能更加精确地推断驱动群落构建的主要生态过程。联合系统发育和功能性状研究干扰和次生林演替对群落系统发育结构物种共存机制的影响,将有助于认识群落物种多样性对干扰的响应及不同演替阶段群落的构建机制,为群落的管理和恢复提供依据。
The mechanism of species co-occurrence has long been an important issue in ecology. The ecological and evolutional similarity of co-occurring species is the crucial information for testing community assembly mechanism.Ecologists have increasingly utilized phylogenetic trees and functional traits to estimate the ecological similarity of species in order to test mecha-nistic community assembly hypotheses.Both the phylogenetic analysis and trait-based method can help to examine the effect of habitat filtering and limiting similarity on the community as-sembly,and provide the novel perspective on the solving of the debate of niche-based and neu-tral theory.According to the modern species co-occurrence theory,the community functional and phylogenetic structure driven by different ecological progresses should be different under different functional traits evolutional pattern.That is phylogenetic clustering should be whether the result of habitat filtering under trait evolutional co

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借鉴生态学的理论提出产业群落概念,通过对产业群落结构和关系链条的分析,指出海洋产业群落内部还存在信任度不高,协作创新不足等问题,在此基础上提出优化海洋产业群落的对策建议.
Based on ecology and technological innovation theory,the paper puts forward a new concept.Then a case study is made to analyze the structure and relational chain of marine industry community,and some pnoblems of the trust degree and collaborative innovation on the inner of marine industry community are pointed out.Then the suggestions are offered for the optimization of marine industry community.

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为研究湖泊沉积物不同深度处的细菌群落结构组成和多样性,选取太湖梅梁湾作为采样点,应用末端限制性片段长度多态性(T-RFLP)技术比较湖泊不同深度沉积物样品中细菌群落的结构组成及其多样性。结果表明:太湖沉积物中细菌具有丰富的多样性,细菌种类和相对丰度与当前已有的可培养细菌研究结果一致。细菌群落结构随着沉积物深度的增加呈现一定的变化规律,相邻近的沉积物分层中细菌群落结构的相似度较高;随着沉积物深度的增加,沉积物中优势菌属发生了一定的变化;表层沉积物与底层沉积物的细菌群落结构相差较大。鉴于氧含量随着沉积物深度的增加而逐渐减少,可以推断氧含量的变化是造成湖泊沉积物中细菌群落结构与多样性差异的主要原因。另外,表层沉积物中的生物扰动也是可能的原因。
To investigate the vertical distribution and diversity of bacterial community composition in the sediments of Taihu Lake , sediment samples were collected from Meiliang Bay in Taihu Lake .Terminal restriction fragment length polymorphism ( T-RFLP) technology was used to analyze the bacterial community composition and diversity in sediment samples of different depths .High bacterial diversities were observed in the sediments of Taihu Lake , and the bacterial species and relative abundance were found to be consistent with those in previous reports based on the culture-dependent method .Additionally , different T-RFLP patterns were observed for samples collected at different depths .Bacterial community compositions derived from those nearby samples showed greater similarities . The dominant bacterial groups varied at different depths .Moreover, the bacterial community compositions of the top and the bottom sediments showed great differences .Dissolved oxygen decreased with the increase of

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对长江下游铁黄沙湿地植被和底栖动物的群落结构进行了研究。结果表明：铁黄沙植被结构相对简单，主要的优势种为芦苇、藨草、菰。芦苇群落带生物量较高，伴生有十几种其他高等植物；藨草群落带生物量较低，群落结构比较单一，但是盖度范围和密度较大。共调查到大型底栖动物10种，以甲壳类动物和环节类动物为主。前者主要分布在高潮滩，并随高程降低逐渐减少，后者主要分布在中低潮滩，中潮滩生物种类数最多。优势种主要为无齿螳臂相手蟹、谭氏泥蟹和河蚬。底栖动物的生物多样性以藨草群落带最好，潮下光滩群落带最差，芦苇群落带和菰群落带介于其中。
The vegetation and the community structure of zoobenthos of ferric yellow-sand wetland in the lower Yangtze River were studied. The results showed that the vegetation structure of ferric yellow-sand was relatively simple, its dominant species were reed, Scirpus triqueter and Zizania caduciflora. There was a relatively higher biomass in reed community belt, and more than 10 species of other higher plant accompanied with it; Scirpus triqueter community belt had relatively low biomass and simple community structure, but its coverage range and coverage density were relatively larger. Moreover, total 10 species of macrobenthos had been investigated, which mainly were crustacean and annelid. The former mainly distributed in the beach with high tide, and it gradually decreased with reducing beach elevation; the latter mainly distributed in the beach with middle tide and low tide, among which the beach with middle tide had the most number of biological species. The dominant species of zoobenth

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指出了湖南仙庾岭风景名胜区属于中亚热带丘陵地区，地带性典型植物群落为常绿阔叶林。对景区总体植物群落类型及其结构、种类组成进行了调查研究，结果表明：秋色叶植物群落可以划分为5类：香樟·枫香群落、枫香群落、檫木群落、白栎群落、山乌桕群落，通过分析各典型群落的种类组成、结构特征及景观特征，为选择和合理运用秋色叶树种资源、山林植物景观修复提供依据，有助于该区系中亚热带含有常绿成分的落叶林植被的演替研究。
Xianyuling landscape resort of Hunan province belongs to the hilly area in middle subtropical zone w hose typical plant community is evergreen broad - leaved forest . This article conducts a research on general plant community type ,structure and the species composition in Xianyuling landscape resort ,and the results show that plants community of fall - color leaf can be divided into five categories:Cinnamomum camphora · Liquidambar community ,Liquidambar community ,Sassafras tzumu community ,Quercus fabri community and Sapium discolor community .Through the analysis of community composition ,structural characteristics and landscape characteristics of various typical communities , the article offers references for the selection and rational use of fall -color tree resources and restoration of forest landscape , w hich are helpful to the succession research of deciduous forest vegetation that contains evergreen composition in this area of middle subtropical zone .

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