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中国植物分类学中的物种问题 总被引:19,自引:1,他引:19
Nooteboom和Peter Raven都认为中国的分类学家往往持有狭隘的物种概念,而这是由于他们缺少足够的标本,尤其是模式标本,因而不能充分研究种的变异性。Raven说这使他相信中国植物分类学中真正的物种概念颇有模式概念的色彩。他们的说法不无道理。的确,中国的植物区系中可能有大量的种其真实身份还有讨论的余地。根据单个性状或完全按营养器官性状来命名新种是常有的事。有些学者甚至把发表新种作为其分类工作的主要目标。现有的、为数非常有限的关于中国植物变异式样研究的证据证明有些“种”实际上是生态宗(Clinopodium)、地理宗(Cunninghamia和Indigofera)或呈地形梯度变异式样的分类群(Lespedeza和Rhododendron)而已。根据表型的可塑性变化而命名的种曾经或仍然被作为“好种”对待(Rorippa)。具各种不同叶形特性的种间杂种的分离系被命名为不同的种(Ilex)。分类学上本来就已经很复杂的无融合生殖复合体由于新种的不断增加而变得更加复杂(Malus)。对一个具有复杂变异式样的种的精心研究导致对25个种名的归并,其中有10个是80年代由中国分类学家发表的(Clematoclethra)。诸如此类的例子随着研究工作的扩大而势必大量增加。传统植物分类学主要或完全以形态性状为依据。外部形态性状具有比较容易观察和记录的优点。分类学种概念能满足多种用途分类的需要。但如果把分类学种概念说成是完全凭分类学家个人的主观判断或甚至偏爱而很难有是非之分就颇成问题了。现在比过去任何时候都有条件对种这个分类阶元作客观的解释。正确的物种概念来自对植物变异式样及其分类学价值的正确和充分的理解。因此,作为标本室分类学家,首先要研究尽可能多的标本。其次,尽可能收编来自其他方面的证据是十分可取的。这些证据即使不是很有用的分类性状,对更好地了解或解释类群的变异式样往往具有重要的意义。分类学家可借以发现他所寻找的分类群在表型或基因型变异上的间断。对这两种间断的合理应用将导致在许多属内种级水平的更加合理的分类。 相似文献
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M.G.Pimenov E.V.Kljuykov 《植物分类学报》2001,39(3):193-202
Xinjianginitsfloraasawhole,aswellasinitssetoftheUmbelliferaespecies ,differsconsid erablyfromtherestofChina,beingcloserintermsofphytogeographytoKazakhstanandKirghizs tan .TheeasternbordersofmanyMiddleAsian ,orevenmorebroadly ,MediterraneanspeciescrossXinji… 相似文献
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M. Ajmal Ali Gábor Gyulai Norbert Hidvégi Balázs Kerti Fahad M.A. Al Hemaid Arun K. Pandey Joongku Lee 《Saudi Journal of Biological Sciences》2014,21(3):204-231
The discipline taxonomy (the science of naming and classifying organisms, the original bioinformatics and a basis for all biology) is fundamentally important in ensuring the quality of life of future human generation on the earth; yet over the past few decades, the teaching and research funding in taxonomy have declined because of its classical way of practice which lead the discipline many a times to a subject of opinion, and this ultimately gave birth to several problems and challenges, and therefore the taxonomist became an endangered race in the era of genomics. Now taxonomy suddenly became fashionable again due to revolutionary approaches in taxonomy called DNA barcoding (a novel technology to provide rapid, accurate, and automated species identifications using short orthologous DNA sequences). In DNA barcoding, complete data set can be obtained from a single specimen irrespective to morphological or life stage characters. The core idea of DNA barcoding is based on the fact that the highly conserved stretches of DNA, either coding or non coding regions, vary at very minor degree during the evolution within the species. Sequences suggested to be useful in DNA barcoding include cytoplasmic mitochondrial DNA (e.g. cox1) and chloroplast DNA (e.g. rbcL, trnL-F, matK, ndhF, and atpB rbcL), and nuclear DNA (ITS, and house keeping genes e.g. gapdh). The plant DNA barcoding is now transitioning the epitome of species identification; and thus, ultimately helping in the molecularization of taxonomy, a need of the hour. The ‘DNA barcodes’ show promise in providing a practical, standardized, species-level identification tool that can be used for biodiversity assessment, life history and ecological studies, forensic analysis, and many more. 相似文献
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居群(population)概念和方法在植物分类学中的应用 总被引:16,自引:1,他引:15
本文依据我们近几年来对水生维管束植物的研究成果,讨论了居群概念和方法对植物分类学的理论和实际的意义与价值,同时对我国今后展开植物学研究提出了若干建议。 相似文献
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Shiro Kobayashi 《Population Ecology》1976,17(2):243-254
Summary A mathematical model of the species-area relation is described for a group of limited species. This model is a modification of that proposed earlier (Kobayashi, 1975), being assumed that the limited species are expected to occur in a habitat under consideration. The model equation gives a sigmoid species-log area curve implying that few rare species are found in a group of species. The good agreement between observation and this model is exemplified with the data of plant and arthropod communities. The implication of parameters involved are examined in connection with those of the preceding model, and the underlying ecology of the model is discussed. Contribution from the Laboratory of Applied Zoology, Yamagata University, No. 83. 相似文献
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我们面对的植物界有极大的多样性,仅绿色植物就有30余万种。Turrill(1938)估计,每年约有2000个有花植物的新种被发表;现在每年发表的新种也许是该数字的一半或稍多于一半。由于物种(species,以下简称“种”)不仅是分类的基本单位,也是生物的繁殖单元和进化单元,因此,生物学家可以为了各自的目的从基因到群落各个不同层次上从事研究,但都离不开与种打交道。一个矛盾的事实是:尽管现代生物学在许多领域成果卓著,但却对“种”的定义和本质这个生物学中最基本、最重要的问题没有取得令人稍为满意的一致意见。 相似文献
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角胫象属Shirahoshizo Morimoto,1962隶属象虫科隐喙象亚科,模式种为Cryptorhynchus rufescens Roelofs.本属昆虫多寄生于松属植物,有些是我国重要林业害虫,如马尾松角胫象Shiraho shizo flavonotatus(Voss),其成虫侵入衰弱的黄山松和堆积的马尾松原木,和其它钻蛀性害虫一起,造成严重危害,据浙江亚热带林研所赵锦年先 相似文献
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Germund Tyler 《Plant Ecology》1996,127(2):215-223
The variability in the cover distribution of vascular plants, accounted for by soil chemical properties and soil depth, on a granite slope with shallow autochtonous soil in southeast Sweden was evaluated using multivariate statistical regression and graphical methods. Soil acidity and soil depth were, to an often high degree, able to account for the variability in the distributions of the ca. 30 most frequent species, including Rumex acetosella, Vincetoxicum hirundinaria, Filipendula vulgaris, Satureja acinos, Geranium columbinum, Silene rupestris, and Arenaria serpyllifolia. The best expression of soil acidity was pH-KCl, though exchangeable Ca and Al were also important measures of the soil-plant relationships. The Ca:Al ratio was inferior in this respect. Also exchangeable or acid soluble phosphate was significantly related to the distribution of several species, whereas soil organic matter content was almost unrelated. 相似文献
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在3S技术支持下,比较分析了科尔沁沙地不同沙漠化成因区域的沙地景观动态变化过程。结果表明:近20年来,以人为活动干扰为主的区域(八仙筒镇),沙漠化土地变化幅度较大,各种沙漠化土地的转化主要表现在沙漠化土地中流动和半固定沙地向固定沙地转化、固定沙地向农田和林地转化;以自然干扰为主的区域(苇莲苏乡),沙漠化土地变化幅度较小,主要表现为各种沙地类型之间的转换;在人为活动为主的区域固定沙地的空间格局变化显著,1985—1995年固定沙地的联合度降低,人为活动干扰较强,而1995—2005年联合度增高,人为活动干扰相对较弱;在自然干扰为主的区域,同一时期空间格局的变化明显的是流动沙地,在1985—1995年,流动沙地斑块破碎度减小,流动沙地发育显著,在1995—2005年,流动沙地的破碎度继续减小,但其面积得到控制,表明治沙效果在这一时期是显著的。 相似文献
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We investigated whether plant diversity and productivity in small-scale soil disturbances, which is known to be higher than
in undisturbed soil, decreases as the density of the disturbances increases. We studied this in an experiment with soil diggings
(15 cm diameter and 15 cm depth) dug at a range of densities, on a north- and a south-facing slope of a watershed in the central
Negev Desert of Israel. The diggings were similar to the commonly occurring pits made by porcupines (Hystrix indica) as they forage for below-ground plant parts. We used four levels of digging density, within the naturally occurring range
in the region, represented by a rectangular plot with rows of diggings dug at four distances between diggings. The plots were
laid out in a blocked design with three replications on both slopes, with each block containing all four levels of digging
density. In the spring of 1992, 1994 and 1995 we measured plant density, species richness and plant productivity in the diggings,
and in adjacent equal-sized undisturbed control areas (“soil matrix”) and on the mounds made by the removed excess soil. Plant
density, species richness and productivity of annual plants were higher in the diggings than in the undisturbed matrix, while
these responses were very low on the mounds. Plant density, species richness and productivity in the diggings, but not in
the matrix or mounds, decreased as digging density increased. This effect varied slightly with location within a watershed
and with annual rainfall. The density of seeds captured in the diggings from outside the digging during the 1995 dispersal
season decreased with increasing digging density, but only on one of the slopes. At the highest digging density, plant density
and species number in the diggings did not decrease down the slope, as expected if interference between diggings in runoff
water capture were the cause of the digging density effect. There was a weak decrease in biomass production in 1994–1995 down
the slope. We used a simple mathematical model to estimate whether the distribution of rainfall intensities that occurred
during the winter of 1994–1995 could result in differences between digging densities in the amount of water captured by the
diggings, and whether this could explain the observed effect of digging density. The model showed that there were four events
during which less water was captured by the diggings at high digging densities, except in the topmost row of diggings. Soil
moisture measurements, however, showed very little difference between diggings at different digging densities. We explain
our findings as the result of the interaction between the properties of the disturbance patch with its surroundings, as the
diggings capture resources in the form of runoff water, and seeds moved primarily by wind. The additional resources and seeds
captured in diggings increase plant density, species richness and productivity relative to the undisturbed matrix. However,
the contrast in plant responses between the disturbed patches and undisturbed soil diminishes at higher digging densities.
We explain this as interference among diggings at close proximity. As we did not detect a decrease in plant responses down
the slopes, we conclude that interference is due to interception of the wind-driven, non-directional flow of seeds. Interception
of the down-slope flow of runoff water by upslope diggings is insufficient to affect plant density, determined at the beginning
of the season. Later in the season, runoff interception may become important for biomass production.
Received: 16 August 1996 / Accepted: 26 October 1997 相似文献
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Clifford J. Jolly 《Evolutionary anthropology》2014,23(1):36-38
A review of the vast literature on the epistemology and ontology of “species” is far beyond the capacity of both the writer and the length‐allotment of this essay, limiting it to a somewhat dogmatic presentation of personal opinions, few of them original. Also prohibited by the prescribed word limit is an account of species concepts considered but not adopted; in many cases, their omission does not do justice to their intellectual content. 相似文献
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Ailanthus altissima (tree of heaven), Simaroubaceae, is an early successional tree, native to China and North Vietnam, which has become invasive in Europe and on all other continents except Antarctica. It is most abundant in urban habitats and along transportation corridors, but can also invade natural habitats. This paper reviews the literature on the morphology, distribution, ecology, habitat requirements, population biology, genetics, physiology, impacts, management and uses of this species. 相似文献
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电子计算机在植物学中的应用 总被引:1,自引:0,他引:1
电子计算机技术的广泛应用和蓬勃发展是本世纪科学技术的卓越成就之一,它将逐渐成为各项科学技术现代化的一个重要标志。电子计算机从1946年问世以来,在近四十年内迅速经历了三代更新。目前正处在第 相似文献
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本文记述了采自我国新疆的小食蚜蝇属1新种,模式标本保存在新疆八一农学院植物保护系昆虫标本室。新源小食蚜蝇Paragus xinyuanensis Li et He,新种(图1) 雄:头顶三角区黑色,近复眼接合缝处被黄色微毛;单眼三角为顶角小于60°的等腰三角形;复眼中区有灰白色短毛排列成的纵带;额淡黄色,被淡黄色短毛,但近触角基部毛黑色;颜淡黄色,被同色短毛,中部隆起,侧面观如图A;触角第一、二节黑褐色,第三节背面及侧面上部1/4黑褐色,其余部分黄褐色。 相似文献