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1.
许多研究表明,物种与高级分类阶元在数量上密切相关,这种关系在地区物种数量预测中具有很高的应用价值。应用中国不同地理类型(保护区、行政区和动物地理亚区)的鸟类物种名录,研究物种与科属的数量相关关系和频次分布规律,结果表明:(1)物种与高级分类阶元在数量上有着极显著相关关系(P<0.01),其中物种—属的相关关系要显著于物种—科,且在对数、乘幂、指数和线数4种模型中,用乘幂模型拟合最好;(2)物种在科属间的频次分布具有规律性(P<0.05),随着物种数/科属的增加,频次迅速减少,在4种模型中,乘幂模型拟合最好,属的规律性较科显著。根据以上结果,物种与科属间的数量强相关关系与物种数量在科属间有规律的频次分布有关。  相似文献   

2.
中国哺乳类物种与科属的数量关系   总被引:2,自引:0,他引:2  
利用中国三种地理类型(自然保护区、行政省和动物地理亚区)的哺乳类名录,分析物种与高等分类阶元(属、科)的数量关系,旨在为利用高等分类阶元替代物种预测生物多样性提供理论依据,研究结果显示:1)不同地理类型中物种-属-科在数量上具有相似的增长趋势,且物种-属、物种-科的数量关系呈极显著相关(P < 0.01)。利用模型对哺乳类物种与科和属的数量关系模拟,乘幂模型拟合效果最佳。2)物种在属间、科间的频次均呈非均匀分布,对结果进行拟合发现对数、乘幂、指数和线性四种模型中,乘幂模型对哺乳类物种与科和属的数量关系模拟效果最佳。综合以上内容认为,哺乳类物种与高级分类阶元在数量和频次分布上存在规律,且可用模型进行很好拟合,这种关系适用于生物多样性预测、评价和保护。  相似文献   

3.
海南种子植物科属与邻近地区科属关系的初步研究   总被引:5,自引:1,他引:5       下载免费PDF全文
高蕴璋   《广西植物》1989,9(3):211-219
<正> 一、前言 本文以海南野生种子植物的科属与越南、菲律宾、澳大利亚和我国台湾,广东(雷州半岛)等地的植物科属统计数字和属相似性,试图探讨它们之间的相似关系,对今后引种驯化和研究华南植物区系有一定的参考作用。  相似文献   

4.
雪雀属鸟类栖息地在中国的分布   总被引:10,自引:0,他引:10  
雪雀属(Montifringilla)属典型的高原鸟类,主要分布于我国青藏高原及其毗邻地区。本文依据现有雪雀属种类的采集记录、文献记载的分布资料,结合野外实地考察,运用GIS(地理信息系统)的叠加和分析功能,综合生境类型资料,建立其野生动物-栖息地关系模型,并预测该属种类栖息地分布。该模型依据适宜于雪雀分布的植被类型和高度叠加后产生雪雀的适宜栖息地,与县界的行政区划图叠加后产生预测有可能分布的县级单元。预测产生的分布图包含高度适宜、适宜和不适宜三种生境类型。本研究预测雪雀属种类的栖息地分布图显示,青藏高原大部分缺乏采集记录的地区具有适宜于雪雀分布的生境类型,具有雪雀分布所必须的潜在条件。而那些有采集记录的县,也仅仅在那些适宜的生境类型中才会有雪雀的分布。  相似文献   

5.
中国分布有跳鼠总科(Dipodoidea)动物3科12属22种,是世界上跳鼠总科物种丰富度最高的国家之一.近年来,随着新种的发现和分类地位的修正,我国跳鼠总科物种的系统发育关系和分布格局也亟待更新.本文通过GenBank下载12个特定基因,串联构建基因矩阵,以贝叶斯法和最大似然法重建22个物种的系统发育树,明确了我国跳...  相似文献   

6.
在广泛搜集、系统整理资料基础上,建立数据库,运用GIS(Geographic Information System)技术分析了中国画眉科鸟类的地理分布格局,并进行鸟类分布相似率比较及以画眉科鸟类为对象进一步探讨中国动物地理区划单元之间的相互关系。结果显示中国画眉科鸟类130种,分属26属,水平分布上具不均性,在动物地理区上表现为西南山地亚区分布最多(114种),其次是滇南山地亚区(94种);有2个物种多样性分布中心,即横断山中心和滇南山地中心。对于鸟类分布相似率,古北界各区、亚区之间的相似率波动较大;而东洋界各区、亚区之间相似率波动较小。中国各动物地理亚区相互关系聚类结果基本为古北界、东洋界各处一个大枝。  相似文献   

7.
热带地区较高的物种多样性与其气候条件有关,但气候如何影响热带地区物种的多样化却未有定论。为了解气候对热带植物多样性的影响,本研究以泛热带植物番荔枝科为研究对象,利用系统发育比较分析方法,计算了该科植物气候生态位的进化速率,并与该科的净多样化速率进行了相关性分析。结果显示:(1)番荔枝科气候生态位的进化速率较低,但新近分化类群的进化速率相对较高;(2)气候生态位下界(低温与低降水)的进化速率较上界(高温与高降水)快;(3)净多样化速率与气候生态位的进化速率,尤其是温度生态位的进化速率紧密相关。本研究揭示了番荔枝科植物气候生态位的进化对其物种多样性形成的重要作用,对该科在当前气候变化下的保护具有参考意义。  相似文献   

8.
中国安息香科——新属———长果安息香属   总被引:2,自引:0,他引:2  
陈涛 《广西植物》1995,15(4):289-292
本文描述了安息香科-新属--长果安息香属,并对新组合和安息香的原始描述作了修订。本属与秤锤树属近缘,但树干无茎刺,具鳞芽,总状花序伞形,花无苞片,四基数,花萼管顶端平截,花冠4深裂,雄蕊8,等长,药隔不突出,子房半下位,柱头不分裂,果实特长,密被长柔毛,上部果喙细长,中部倒卵形,具8条纵梭,下部渐狭,延长成柄状,可以区别。本属的芽具鳞片,花无苞片,四基数,与银钟花属相似,但后者的花萼管顶端具4裂片  相似文献   

9.
10.
卫矛属(Euonymus L.)和沟瓣属(Glyptopetalum Thw.)的系统关系长期以来备受争议,为理清它们之间的关系,该研究选择沟瓣属12种、卫矛属17种和假卫矛属(Microtropis Wall.ex Meisn.)2种,共计31个分类单元(OTUs),测量并统计了56个形态性状,同时利用聚类分析(UP...  相似文献   

11.
我国自由生活中气门目螨类科属分类   总被引:1,自引:0,他引:1  
粱来荣  胡成业 《蛛形学报》1994,3(2):148-157
对我国已知自由生活中气门目螨类15科、51属列出科、属检索表。  相似文献   

12.
报道了中国兰科2个新记录属及5个新记录种:固唇兰属(Plocoglottis)、栖林兰属(Drymoda)、滇南固唇兰(Plocoglottis bokorensis)、栖林兰(Drymoda siamensis)、泰国牛角兰(Ceratostylis siamensis)、景洪白蝶兰(Pecteilis hawkesiana)、三脉贝母兰(Coelogyne trinervis)、浮萍毛兰(Eria spirodela).对2个属及5个种进行了特征描述,并对比了近似种.  相似文献   

13.
作者在研究园林叶螨时,在安徽黄山发现了属于叶螨族Tetranychini Reck,1950的一新属新种,属订名为忻叶螨属Xinella gen.nov.,,以示作者对复旦大学忻介六教授的崇高敬意和感谢。忻叶螨属Xinella Ma et Wang,新属 模式种:黄山忻叶螨Xinella huangshanensis,新种。  相似文献   

14.
新疆甘草属(Glycyrrhiza) 的生态分布及其经济利用   总被引:2,自引:0,他引:2       下载免费PDF全文
 新疆分布的甘草属植物共五种:甘草(Clycyrrhiza uralensis)、光果甘草(G.glabra)、粗毛甘草(G. aspera)、胀果甘草(G.inflata)、科氏甘草(G.korshinskyi)。出现于新疆88%的县市,各大河流沿岸、泉水溢出带及冲积平原。在区系上与中亚关系密切。空气干燥度、年平均温度及土壤盐碱含量对不同种甘草的分布都有影响。甘草虽然在南、北、东疆都有分布,但以北疆为主。甘草分布地区的大气干燥度从1.37—237.3,而以3—6最佳;年均温度为0.4—14℃,而以4—8℃为最适宜。甘草常与苦豆子(Sophora alopecuroides)、芨芨草(Achnatherum splendens)、芦苇(Phragmites communis)、大叶白麻(Poacynum hendersonii)等组成群落。光果甘草可与灰杨(Populus pruinosa)、柽柳(Tamarix chinensis)、假苇拂子茅(Calamagrostis Pseudophragmites)等组成群落。胀果甘草常与不同比例的胡杨(Populus diversifolia)、铃铛刺(Halimodendron halodendron)、柽柳、芦苇、大叶白麻、骆驼刺(Alhagi pseudalhagi)、花花柴(Karelinia caspica)等组成群落。粗毛甘草多为田间、果园及路旁荒地杂草。为了保持甘草资源的持续利用并充分发挥其效益,应建立合理的挖采制度,建立甘草生产基地,并开展甘草的综合利用研究。  相似文献   

15.
Krieger  Axel  Porembski  Stefan  Barthlott  Wilhelm 《Plant Ecology》2003,167(2):283-292
Inselbergs are monolithic, old and stable landscape elements with a worldwide distribution. On inselbergs, relatively old (i.e. hundreds of years old) rock pools form a unique habitat that offers locally wet conditions in an otherwise edaphically and microclimatically dry environment. They occur as seasonally water-filled depressions with a thin layer of soil, and are mainly inhabited by ephemerals and cryptogams. Even during the rainy season, they often become dry if precipitation is lacking for a few days. Between 1990 and 1999, about 200 rock pools in the Ivorian savanna zone were examined on a regular basis. Absolute and relative turnover rates were calculated: values ranged from 0.00 to 3.00 and 0 to 78%, respectively. Mean turnover was 0.19 (17%). The turnover in the SRPs increased significantly with soil depth and area. No correlation was found between turnover and species number of the pools, which increased significantly with area. The highest turnover was shown by the annual Cyanotis lanata. The turnover of therophytes was higher than those of other life-forms. Turnover and frequency of the species were only weakly correlated. In an environment of frequent stochasticity, climatic disturbances are the major driving force determining community dynamics (e.g. local extinctions and immigrations) of these habitat islands.  相似文献   

16.
Information on bryophyte diversity and rarity were combined withinformation on soil conditions and land use for Walloon Brabant (centralBelgium, 1091 km2) in order to investigate whichlandscape features sustain the most rare and diverse species assemblages.Presence–absence of 325 bryophyte species was recorded in 87 grid-squaresof 4 × 4 km. Species diversity was significantly correlatedwith forest cover (r = 0.71, P <0.001), sandy soils (r = 0.61, P <0.001), loamy soils, (r = –0.68,P < 0.001), and agricultural fields(r = –0.49, P < 0.001). Themost diverse grid-squares possessed up to 182 species and were characterized byat least 10% forest cover and the presence of unique micro-habitats.Grid-squares with forest cover reaching at least 10% but lacking uniquemicro-habitats contained between 90 and 130 species. Below 10% forest cover,diversity ranged between 55 and 110 species per grid-square. However, even theleast diverse cultivated areas included a significant amount of the regionallyrare species. A number of the latter are characteristic in other areas forspecific primary habitats lacking in Walloon Brabant but display an unexpectedability to disperse throughout hostile areas and colonize secondary habitats.The tendency of such species to occur in man-made habitats decreased our abilityto predict species richness and rarity from landscape features and soilconditions.  相似文献   

17.
Understanding how overall patterns of spatial variation in species richness are affected by distributional patterns of species has been an area of growing concern. In the present study, we investigated the relative importance of common and rare species as contributors in overall plant species richness. We further examined if the effects of common or rare species in richness patterns are affected by the size of the sampling units and if the observed patterns hold at different habitats. We used a dataset of 5,148 higher plant species distributed across 16,114 sampling plots located in 240 sites of the NATURA 2000 network of Greece. We ranked all species based on the number of sites they occupied and we developed a common to rare and a rare to common sequence. We correlated those sequences with cumulative species distributions. We performed this analysis in nine different sizes of sampling units and in three different datasets referring to (a) all habitat types together, (b) coniferous habitats only and (c) alpine habitats only. Our analysis showed that despite the proportionally higher numbers of restricted species, widespread species make a greater contribution to overall richness patterns and that this observed pattern does not depend on the size of the sampling units. Moreover, the observed pattern stands for different habitat types. Our findings support the generality of this pattern and highlight the importance of widespread species as adequate indicators of biodiversity patterns at various habitat types. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

18.
We investigated long-term trends in brown macroalgal assemblages inhabiting shallow subtidal rocky bottoms under the influence of thermal effluent discharge from the Brazilian nuclear power plant (BNPP). Three operational periods based on the units of the BNPP were analysed: T0 = pre-operational, between the years 1980 and 1983; T1 = operational period of unit 1, between 1988 and 1999; and T2 = operational period of units 1 and 2, between 2005 and 2012. Using generalized linear mixed models (GLMMs), we found significant declines in the numbers of genera and species over time. More than half of the species of brown macroalgae disappeared during T2. In addition, the numbers of macroalgal genera and species were inversely related to the local surface seawater temperatures. Multivariate analyses revealed a clear separation between the years of T2 and those of T0, indicating long-term changes in the community assemblages. Among the most common species in the area, the frequencies of Canistrocarpus cervicornis, Dictyopteris delicatula, Hincksia mitchelliae, Sargassum spp. and Sphacelaria tribuloides decreased during T2, while Padina gymnospora maintained rather high yearly frequencies during T2 (>40%). Our data suggest that seawater temperatures consistently higher than 30 °C together with peaks higher than 35 °C may have triggered the decline in the brown algae on rocky bottoms under the influence of the BNPP discharge. These results from southern Brazil are consistent with studies from other locations that ascribe changes in seaweed diversity to increasing seawater temperatures, highlighting the sensitivity of brown macroalgae to thermal stress and demonstrating their effectiveness as an ecological indicator for monitoring the effects of nuclear power plant effluents on coastal environments.  相似文献   

19.
Sampling distributions of species composition counts from four large data sets were collected by point techniques. Results show good agreement between observed and expected frequencies under binomial distributions for all species measured with the Tidmarsh wheel. However, with the Levy bridge where observations are not independent, greater variance occurred for species with low frequencies. The results were used to specify those sample sizes needed to achieve any pre-determined precision. The traditionally accepted sample size of 200 is adequate for detecting a change with 20% precision in only the dominant species (mean composition of over 25%). Detecting change in species with a frequency of less than 5% will require in excess of 1200 points to achieve a 20% precision.  相似文献   

20.
Matthews  Jeffrey W. 《Plant Ecology》2004,174(2):271-278
Biotas of both geographical islands and habitat islands are often nested subsets of the biotas of successively more species-rich islands within the same system. The life history characteristics of a species may determine how that species contributes to the general pattern of species nestedness. Here, I investigate the floras of 56 sedge meadow wetlands in northern Illinois (USA) in order to characterize the degree of nestedness in these communities, determine which individual plant species contribute to the nested pattern, and investigate species characteristics that might be related to nonrandom patterns of distribution in individual plant species. The entire assemblage of species at all sedge meadows was significantly nested. Species richness and area were significantly correlated, and the nested pattern was closely related to site area, suggesting that species drop out of the assemblage in a predictable order as site area decreases. Some individual species exhibited nonrandom distributions across the sites, occurring more often in large, species-rich sites. Large sites were more likely than smaller sites to contain conservative species, i.e., those typical of pristine natural habitat, whereas nonconservative species were distributed more randomly among sites. Nested patterns of distribution of conservative species with respect to site area may result from their high probability of extinction on small sites or from a tendency for required habitats to co-occur on the same large sites. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

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