冀西北坝上地区灯下蛾类群落结构特征

对冀西北坝上地区蛾类进行了逐日灯诱监测,以微软系统的Excel列表、作图,进行蛾类群落的种-多度曲线作图及群落多样性(H')、均匀度(J')、物种丰富度(S)和个体数(N)的时间和空间分布的处理,并做了多样性分析。结果表明:该区蛾类已知16科173属247种,夜蛾科是该区蛾类的优势类群,旋幽夜蛾、网锥蛾野螟(草地螟)和小菜蛾为当地优势种。从5月到9月蛾类多样性指数、物种丰富度和个体数基本呈上升趋势,多样性指数与均匀度(r=0.9477)、物种数(r=0.7785)、个体数(r=0.9704)相一致。不同月份间的蛾类相似程度差异较大,种-多度关系符合对数正态分布模型,研究认为坝上地区蛾类赖以生存的生态环境稳定,生态环境条件保持较好。     

北京及周边地区刺蛾科昆虫系统发育多样性研究

【目的】鳞翅目刺蛾科(Lepidoptera:Limacodidae)昆虫是重要经济、行道林木的主要害虫,本试验旨在研究北京及周边地区刺蛾科昆虫的系统发育多样性,阐明其群落结构组成与环境因子之间的关系,为北京及周边地区林木害虫防治和生态系统环境保护提供科学依据。【方法】采用灯诱法于2010-2013年间进行样品采集,基于DNA条形码技术及形态特征对9个刺蛾科昆虫群落进行物种识别和鉴定,利用R软件包进行物种丰富度指数、多样性指数和系统发育多样性指数计算及相关性分析。【结果】9个群落间物种多样性和系统发育多样性之间存在差异,北部燕山地区具有较高的物种丰富度和系统发育多样性,可能与植物类型不同有关;通过多种方法分别计算系统发育多样性,结果表明系统发育多样性指数对于系统发育树构建方法和物种内遗传差异不敏感;系统发育多样性与环境因子相关性研究结果表明,该地区刺蛾科群落系统发育多样性与温度季节变化存在显著正相关性。【结论】北京及周边地区刺蛾科昆虫群落结构具有地理差异,温度季节变化可能会造成环境异质性的增加,从而增加了群落系统发育多样性的复杂度。     

天童常绿阔叶林中常绿与落叶物种的物种多度分布格局

物种多度分布是对群落内不同物种多度情况的数量描述, 作为理解群落性质的基石, 其形成机制受到广泛关注。常绿与落叶物种是两类有着不同物候性状与生长策略的物种集合, 它们普遍共存于常绿阔叶林中。在天童20 ha常绿阔叶林动态监测样地内, 虽然常绿物种在物种多度和胸高断面积等指标上占有绝对优势, 但其在物种丰富度上却不及落叶物种。分析两者在常绿阔叶林中的物种多度分布特征, 能够为理解常绿阔叶林内物种多样性的维持机制提供一个全新的视角。为此, 我们基于天童样地的植被调查数据, 一方面利用累积经验分布函数对两类生活型植物的物种多度分布进行描述, 使用Kolmogorov-Smirnov检验(K-S检验)判断其差异性; 另一方面, 采用纯统计模型、生态位模型和中性理论模型对二者的物种多度分布曲线进行拟合, 并基于K-S检验的结果以及AIC值进行最优模型的筛选。结果显示: (1)常绿与落叶物种的物种多度分布曲线间并无显著差异。(2)在选用的3类模型中, 中性理论模型对于两类物种多度分布曲线的拟合效果都最好, 而生态位模型的拟合效果则一般。从上述结果可以看出, 尽管常绿与落叶物种在物种数量和多度等方面均存在差异, 但它们却有着近似的物种多度分布格局以及相近的多样性维持机制。然而, 鉴于模型拟合的结果只能作为理解群落多样性构建机制的必要非充分条件, 故而只能初步判定中性过程对于常绿与落叶物种的物种多样性格局影响更大, 却不能排除或衡量诸如生态位分化等其他过程在两类生活型多样性格局形成中的贡献。     

中条山油松人工林下物种对群落物种丰富度分布格局的贡献

该研究以中条山油松人工林群落为研究对象,研究林下不同大小的子群落对群落物种丰富度分布格局的贡献,并确定影响该区域群落物种丰富度分布格局的关键种,为区域物种多样性保护提供理论依据。结果表明:(1)该地区林下物种频度分布格局呈明显右偏,且不同样方物种丰富度存在明显差异。(2)常见种对群落丰富度分布格局的贡献大于稀有种。(3)最常见的物种解释了整个群落物种丰富度格局的88.4%(P0.01),而最稀有物种仅解释了24.5%(P0.05),去除最稀有物种后,最常见物种可以解释剩余物种的90.8%(P0.01),而去除最常见物种后,最稀有物种仅能解释剩余物种的48.6%(P0.01)。(4)当子群落中常见种越多时,子群落与整个群落的丰富度分布格局相关性越高。(5)连翘(Forsythia suspensa)、太平花(Philadelphus pekinensis)、鞘柄菝葜(Smilax stans)、多歧沙参(Adenophora wawreana)、金花忍冬(Lonicera chrysantha)等对群落物种丰富度分布格局的贡献最大,但并非越常见的物种对群落丰富度格局贡献越大。(6)与频度较高物种的种间关联度低的物种对于群落物种的分布格局贡献较大,但此解释并不适用于稀有种。研究发现,稀有种对中条山油松人工林群落物种丰富度分布格局存在较大的贡献,所以在油松人工林物种多样性保护过程中并不能只关注常见种而忽视稀有种。     

两种珍稀植物群落物种多度分布的核方法研究

首次提出物种多度分布的非参数核密度估计方法,介绍了此方法的构造和主要性质。珍稀濒危植物观光木群落和长苞铁杉群落的乔木层、灌木层、所有木本植物物种多度分布实例拟合结果表明,核方法能很好地描述群落物种多度分布。非参数核估计方法是群落物种多度分布模拟的一种有效方法,它丰富了物种多度分布拟合方法,为珍稀濒危植物的管理与保护提供了理论参考。     

后河国家级自然保护区蛾类昆虫的季节多样性

后河国家级自然保护区位于湖北省与湖南省交界处,属于武陵山脉,与湖南壶瓶山国家级自然保护区相邻。该保护区自然环境优越,为昆虫繁衍提供了良好条件。为了研究后河国家级自然保护区蛾类昆虫的季节动态变化,在春、夏、秋三季,选取茅坪、湾潭和独岭为样地,采用灯光诱集方法,对后河国家自然保护区的蛾类昆虫群落多样性及季节变化进行了调查。采用α-多样性测度方法,分析了物种丰富度(S)、多样性指数(科、属及种级)(H)、均匀度指数(J)和优势度指数(D)。结果表明:后河国家自然保护区的蛾类昆虫分属21科173属227种,其中夜蛾科的丰富度最高达到62。随后是,尺蛾科和螟蛾科昆虫,它们的物种丰富度指数分别为为58和25。从各科个体数来看,尺蛾科昆虫最多有423头,灯蛾科排第二,有351头,第三的是夜蛾科昆虫有336头。蛾类昆虫的物种丰富度指数、多样性指数、均匀度指数及优势度指数随季节变化而变化。蛾类昆虫的物种丰富度指数以夏季最高,达到117;然后依次是秋季和春季。科级、属级和种级多样性指数也以夏季最高,分别为2.22、4.05和4.29。均匀度指数和优势度指数以春季最高,分为2.40和0.12。研究得出后河国家级自然保护区的生态环境好。     

DNA条形码及其在海洋浮游动物生态学研究中的应用

浮游动物的准确鉴定是浮游动物生态学研究的基础.传统的基于形态特征的鉴定不仅费时费力,而且部分类群特别是浮游幼体由于形态差异细微,鉴定存在困难,导致物种多样性被低估.DNA条形码(DNA barcodes)技术为浮游动物物种鉴定提供了一个有力工具,已迅速应用于海洋浮游动物生态学研究.本文介绍了DNA条形码的基本概念、优势及局限性,总结了该技术(主要是基于线粒体细胞色素C氧化酶第一亚基(mtCOI)基因序列片段的DNA条形码)在海洋浮游动物物种快速鉴定、隐种发现、营养关系研究、生物入侵种监测、群落历史演变反演、种群遗传学以及生物地理学中的成功应用.随着DNA条形码数据库信息量覆盖率的不断提高和新一代测序技术的快速发展,DNA条形码将提供除了种类鉴定外更加丰富的信息,从而帮助人们更好地理解海洋浮游动物的多样性及其在生态系统中的功能,推动海洋浮游动物生态学的发展.     

亚高寒草甸植物群落种多度分布关系及相似性对氮磷添加的响应

以青藏高原亚高寒草甸为研究对象,采用随机区组设计,通过连续4a添加N、P,研究了不同施肥(N、P、N+P)处理下群落物种丰富度、种多度分布模式以及群落相似性的变化特征。结果显示:(1)N、N+P连续添加4年后,随N素添加水平的增加,草地植物群落物种丰富度逐渐降低(P0.001);种多度分布曲线的斜率逐渐增大;N+P添加处理对植物群落物种丰富度和种多度分布(SAD)曲线的影响较单独N添加处理更显著,如N15P15处理下群落物种丰富度的降幅最大,达对照群落的65.5%;(2)单一N或N+P处理中,不同添加量间的植被组成趋异,而相同添加量的植被组成趋同(stress level=0.152);(3)N、N+P添加引起刷状根的丛生型禾本科植物逐渐在植物群落中占据优势;(4)P素添加对群落物种丰富度、种多度分布曲线、群落相似性和不同生长型组成及比例的影响不显著;(5)植物生长型特征和N/P添加处理可解释56.97%植物群落的物种多度分布特征。这些结果表明:亚高寒草甸地区N添加引起植物群落组成的重新排序、优势种的变化、SAD曲线逐渐陡峭,群落的相似性增加;N富集时,添加P素会增加N素的利用效率,且群落结构受N、P供应水平的影响。     

DNA条形码技术在河北保定、廊坊地区鳞翅目昆虫上的应用及小型区域数据库的构建

【目的】为了探究DNA条形码技术和小型区域数据库在蛾类鉴定上的可行性,本研究利用条形码通用引物扩增了采自河北保定、廊坊地区10种夜蛾82个样本的线粒体细胞色素c氧化酶亚基I(Mitochondrial cytochrome c oxidase subunit I,COⅠ)基因序列。【方法】基于进化树、距离、阈值和特征的方法。【结果】虽然整体分类效果较好,但基于进化树、距离、阈值的方法都无法将二点委夜蛾Athetis lepigone进行较好的分类;样本LF110802.008总是被分入标瑙夜蛾Maliattha signifera类群,与形态学分类结果发生分歧。基于特征的方法运用核基因28S进行分析,结果与形态分类一致。同时还探讨了基于特征方法得到的诊断特征数目与样本数量之间的关系,发现两者密切相关;基于特征的方法对小样本量的鉴定也比较有效。本研究建立了小型区域的DNA条形码数据库,使物种识别具有更强的针对性,有利于提高地区性蛾类病虫害防治效果。【结论】在蛾类鉴定中,DNA条形码有很好的分类效果,小型区域数据库很有实际应用价值。     

山西翅果油树上三种重要鳞翅目害虫的形态 和分子鉴定及生活史观察

【目的】明确山西翅果油树Elaeagnus mollis上发生危害的3种鳞翅目害虫形态鉴定特征及生活史特性,并基于mtDNA COI基因DNA条形码对这3个种进行快速物种识别鉴定。【方法】通过观察山西翅果油树上3种鳞翅目害虫成虫外部形态和解剖拍照雌、雄性外生殖器特征,利用PCR扩增对待测样本COI基因DNA条形码序列进行测定,与GenBank数据库中同源序列进行比对,基于COI基因DNA条形码序列构建邻接树 (neighborjoining, NJ),结合形态学研究结果对这3种鳞翅目害虫开展种类鉴定。【结果】形态学鉴定结果表明,危害山西翅果油树的3种鳞翅目害虫为榆兴透翅蛾Synanthedon ulmicola、兴透翅蛾Synanthedon sp.和斜纹小卷蛾Apotomis sp.。对这3个种的外部形态和雌、雄性外生殖器鉴别特征进行了描述和绘图。DNA条形码序列比对分析结果显示,榆兴透翅蛾与GenBank数据库中Synanthedon sequoiae的COI基因核苷酸序列一致性为90.7%,兴透翅蛾与GenBank数据库中Synanthedon spheciformis的COI基因核苷酸序列一致性为90.0%,斜纹小卷蛾与GenBank数据库中Apotomis capreana的COI基因核苷酸序列一致性为92.7%,NJ树聚类分析结果显示3个种分别形成明显的单系分支,与形态学和序列比对鉴定结果相吻合。【结论】本研究基于形态学鉴定和COI基因DNA条形码分子鉴定明确了危害山西翅果油树的3种鳞翅目害虫——榆兴透翅蛾、兴透翅蛾和斜纹小卷蛾,并提供了3个种的形态鉴定特征、生活史资料,为重要经济树种翅果油树的害虫防治提供了理论依据和科学资料。     

Environmental barcoding: a next-generation sequencing approach for biomonitoring applications using river benthos

Timely and accurate biodiversity analysis poses an ongoing challenge for the success of biomonitoring programs. Morphology-based identification of bioindicator taxa is time consuming, and rarely supports species-level resolution especially for immature life stages. Much work has been done in the past decade to develop alternative approaches for biodiversity analysis using DNA sequence-based approaches such as molecular phylogenetics and DNA barcoding. On-going assembly of DNA barcode reference libraries will provide the basis for a DNA-based identification system. The use of recently introduced next-generation sequencing (NGS) approaches in biodiversity science has the potential to further extend the application of DNA information for routine biomonitoring applications to an unprecedented scale. Here we demonstrate the feasibility of using 454 massively parallel pyrosequencing for species-level analysis of freshwater benthic macroinvertebrate taxa commonly used for biomonitoring. We designed our experiments in order to directly compare morphology-based, Sanger sequencing DNA barcoding, and next-generation environmental barcoding approaches. Our results show the ability of 454 pyrosequencing of mini-barcodes to accurately identify all species with more than 1% abundance in the pooled mixture. Although the approach failed to identify 6 rare species in the mixture, the presence of sequences from 9 species that were not represented by individuals in the mixture provides evidence that DNA based analysis may yet provide a valuable approach in finding rare species in bulk environmental samples. We further demonstrate the application of the environmental barcoding approach by comparing benthic macroinvertebrates from an urban region to those obtained from a conservation area. Although considerable effort will be required to robustly optimize NGS tools to identify species from bulk environmental samples, our results indicate the potential of an environmental barcoding approach for biomonitoring programs.     

DNA barcoding reveals a cryptic nemertean invasion in Atlantic and Mediterranean waters

For several groups, like nemerteans, morphology-based identification is a hard discipline, but DNA barcoding may help non-experts in the identification process. In this study, DNA barcoding is used to reveal the cryptic invasion of Pacific Cephalothrix cf. simula into Atlantic and Mediterranean coasts. Although DNA barcoding is a promising method for the identification of Nemertea, only 6 % of the known number of nemertean species is currently associated with a correct DNA barcode. Therefore, additional morphological and molecular studies are necessary to advance the utility of DNA barcoding in the characterisation of possible nemertean alien invasions.     

Response of epilithic diatom assemblages to water pollution in rivers in the Tokyo Metropolitan area, Japan

1. During the spring of 1992, fifty-two quantitative diatom samples were collected from twenty-eight rivers located in the Tokyo Metropolitan area, Japan, to study the response of the diatom assemblages to water pollution (assessed using physical and chemical data determined monthly from April 1987 to March 1992). 2. Species composition was analysed by means of biotic indices (Pantle and Buck's saprobic index) and multivariate analyses [two-way indicator species analysis (TWINSPAN) for classification and canonical correspondence analysis (CCA) for ordination]. Species-abundance relationships were analysed using diversity indices (species richness, Shannon's diversity index and Pielou's evenness index) and rank-abundance patterns (rank-abundance curves). 3. CCA revealed two major gradients. The first corresponded to organic pollution and eutrophication. The second corresponded to variables related to geographical location. Four main station groups were determined by TWINSPAN. The location of the indicator species of groups 1–3 along the CCA axis 1 is consistent with their known pollution tolerance characteristics. Indicator species for group 4 had larger scores on CCA axis 2, and are representative of brackish water environments. 4. Species richness tended to be higher in the intermediate range of water pollution. Pielou's evenness index and Shannon's diversity index followed the same tendency but only weakly. 5. The rank-abundance patterns of diatom assemblages were more or less constant in all stations. The curves were very similar in shape, differing only in length and gradient (directly related to species richness and evenness, respectively). 6. The results of this study indicate that the response of diatom assemblages to environmental change can be observed in species compositional variation. Multivariate analyses and pollution indices revealed this response and are to be preferred to species diversity measures.     

植物物种的快速鉴定与iFlora：DNA条形码在马先蒿属中的应用

DNA条形码技术就是利用一段较短的标准DNA序列对物种进行快速鉴定。与基于植物外部形态特征的传统分类鉴定方法相比,DNA条形码具有高效、准确,且易于实现自动化和标准化的特点。马先蒿属（PedicularisL．）植物具对生（轮生）叶的种类70％以上分布在中国．近缘种间形态上非常相似,鉴定较为困难。研究选取马先蒿属具对生（轮生）叶类群43种164份样品,利用叶绿体基因（rbcL、matK、trnH-psbA）和核基因（ITS）条形码片段,采用建树法和距离法检验4个条形码对这些物种的鉴定效果。结果表明,ITS片段用于建树法和距离法的鉴别率分别为81．40％和89．57％,其鉴别率高于3个叶绿体基因片段和任一基因片段的组合条码。另外,利用ITS成功解决了一些疑难种的分类问题。DNA条形码在马先蒿属研究中的实用性为新一代植物志（iFlora）实现物种的快速和准确鉴定提供了有力支持,并能为分类学、生态学、进化生物学、居群遗传学和保护遗传学等分支学科的研究提供重要信息。     

DNA barcoding of arid wild plants using rbcL gene sequences

DNA barcoding is currently gaining popularity due to its simplicity and high accuracy as compared to the complexity and subjective biases associated with morphology-based identification of taxa. The standard chloroplast DNA barcode for land plants recommended by the Consortium for the Barcode of Life (CBOL) plant working group needs to be evaluated for a wide range of plant species. We therefore tested the potential of the rbcL marker for the identification of wild plants belonging to diverse families of arid regions. Maximum likelihood tree analysis was performed to evaluate the discriminatory power of the rbcL gene. Our findings showed that using rbcL gene sequences enabled identification of the majority of the samples (92%) to genus level and only 17% to species level.     

Fast Census of Moth Diversity in the Neotropics: A Comparison of Field-Assigned Morphospecies and DNA Barcoding in Tiger Moths

The morphological species delimitations (i.e. morphospecies) have long been the best way to avoid the taxonomic impediment and compare insect taxa biodiversity in highly diverse tropical and subtropical regions. The development of DNA barcoding, however, has shown great potential to replace (or at least complement) the morphospecies approach, with the advantage of relying on automated methods implemented in computer programs or even online rather than in often subjective morphological features. We sampled moths extensively for two years using light traps in a patch of the highly endangered Atlantic Forest of Brazil to produce a nearly complete census of arctiines (Noctuoidea: Erebidae), whose species richness was compared using different morphological and molecular approaches (DNA barcoding). A total of 1,075 barcode sequences of 286 morphospecies were analyzed. Based on the clustering method Barcode Index Number (BIN) we found a taxonomic bias of approximately 30% in our initial morphological assessment. However, a morphological reassessment revealed that the correspondence between morphospecies and molecular operational taxonomic units (MOTUs) can be up to 94% if differences in genitalia morphology are evaluated in individuals of different MOTUs originated from the same morphospecies (putative cases of cryptic species), and by recording if individuals of different genders in different morphospecies merge together in the same MOTU (putative cases of sexual dimorphism). The results of two other clustering methods (i.e. Automatic Barcode Gap Discovery and 2% threshold) were very similar to those of the BIN approach. Using empirical data we have shown that DNA barcoding performed substantially better than the morphospecies approach, based on superficial morphology, to delimit species of a highly diverse moth taxon, and thus should be used in species inventories.     

DNA barcoding Indian marine fishes

DNA barcoding has been adopted as a global bio-identification system for animals in recent years. A major national programme on DNA barcoding of fish and marine life was initiated in India by the authors during 2006 and 115 species of marine fish covering Carangids, Clupeids, Scombrids, Groupers, Sciaenids, Silverbellies, Mullids, Polynemids and Silurids representing 79 Genera and 37 Families from the Indian Ocean have been barcoded for the first time using cytochrome c oxidase I gene (COI) of the mtDNA. The species were represented by multiple specimens and a total of 397 sequences were generated. After amplification and sequencing of 707 base pair fragment of COI, primers were trimmed which invariably generated a 655 base pair barcode sequence. The average Kimura two parameter (K2P) distances within species, genera, families, orders were 0.30%, 6.60%, 9.91%, 16.00%, respectively. In addition to barcode-based species identification system, phylogenetic relationships among the species have also been attempted. The neighbour-joining tree revealed distinct clusters in concurrence with the taxonomic status of the species.     

Applying plant DNA barcodes to identify species of Parnassia (Parnassiaceae)

DNA barcoding is a technique to identify species by using standardized DNA sequences. In this study, a total of 105 samples, representing 30 Parnassia species, were collected to test the effectiveness of four proposed DNA barcodes (rbcL, matK, trnH-psbA and ITS) for species identification. Our results demonstrated that all four candidate DNA markers have a maximum level of primer universality and sequencing success. As a single DNA marker, the ITS region provided the highest species resolution with 86.7%, followed by trnH-psbA with 73.3%. The combination of the core barcode regions, matK+rbcL, gave the lowest species identification success (63.3%) among any combination of multiple markers and was found unsuitable as DNA barcode for Parnassia. The combination of ITS+trnH-psbA achieved the highest species discrimination with 90.0% resolution (27 of 30 sampled species), equal to the four-marker combination and higher than any two or three marker combination including rbcL or matK. Therefore, matK and rbcL should not be used as DNA barcodes for the species identification of Parnassia. Based on the overall performance, the combination of ITS+trnH-psbA is proposed as the most suitable DNA barcode for identifying Parnassia species. DNA barcoding is a useful technique and provides a reliable and effective mean for the discrimination of Parnassia species, and in combination with morphology-based taxonomy, will be a robust approach for tackling taxonomically complex groups. In the light of our findings, we found among the three species not identified a possible cryptic speciation event in Parnassia.     

After 7 years and 1000 citations: comparative assessment of the DNA barcoding and the DNA taxonomy proposals for taxonomists and non-taxonomists

In 2003, two different approaches-DNA taxonomy and DNA barcoding-were simultaneously proposed to overcome some of the perceived intrinsic weaknesses of the traditional morphology-based taxonomical system, and to help non-taxonomists to resolve their crucial need for accurate and rapid species identification tools. After 7 years, it seems unlikely that a completely new taxonomical system based on molecular characters only (DNA taxonomy) will develop in the future. It is more likely that both morphological and molecular data will be simultaneously analyzed, developing what has been coined as "integrative taxonomy". Concerning DNA barcoding, it is now clear that it does not focus on building a tree-of-life nor to perform DNA taxonomy, but rather to produce a universal molecular identification key based on strong taxonomic knowledge that is collated in the barcode reference library. The indisputable success of the DNA barcoding project is chiefly due to the fact that DNA barcoding standards considerably enhance current practices in the molecular identification field, and standardization offers virtually endless applications for various users.     

真菌DNA条形码技术研究进展

DNA条形码(DNA barcoding)技术作为一门新兴的物种鉴定方法以其灵敏、精确、方便和客观的优势,在动植物和微生物的分类鉴定中已经得到广泛应用.真菌鉴定中常用作标准条形码的是核核糖体DNA内转录间隔区(Internal transcribed spacer,ITS),如今也有一些新型条形码被发现和应用到实际操作中,如微条形码、ND6、EF3.本文对DNA条形码技术的产生和发展做出了总结,通过研究其在真菌中应用的实际案例分析了DNA条形码技术的优缺点及发展趋势,并指出DNA条形码技术将以全新的视角来弥补传统分类学的不足,最终实现生物自身的序列变异信息与现有形态分类学的结合.