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1.
高粱属植物的地理分布   总被引:1,自引:0,他引:1  
为探讨高粱属(Sorghum Moench)的系统发育关系,通过野外调查及查阅标本和文献资料,对高粱属植物的地理分布进行了整理和研究。高粱属植物约有29种,分布于全世界热带到温带地区,其中澳大利亚22种,亚洲15种,非洲9种,欧洲3种,地中海2种,美洲6种。中国有5种,分布在东北、西南到华南各省(区)。高粱属有5亚属,仅高粱亚属(subgen.Sorghum)延伸至新世界,其他亚属均分布在旧世界,高粱亚属覆盖非洲并扩散到全世界热带到温带地区;拟高粱亚属(subgen.Parasorghum)分布在非洲、亚洲、澳大利亚;有柄高粱亚属(subgen.Stiposorghum)主要分布在澳大利亚,个别种分布到亚洲;多毛高粱亚属(subgen.Chaetosorghum)分布在澳大利亚;异高粱亚属(subgen.Heterosorghum)分布在澳大利亚和亚洲。这表明澳大利亚东北部是高粱属的现代分布中心和多样化中心,非洲东北部和热带亚洲是否是高粱属的起源地尚需确证。  相似文献   

2.
禾本科燕麦属植物的地理分布   总被引:1,自引:0,他引:1  
为探讨燕麦属(Avena L.)植物的地理分布,通过野外调查及查阅标本和文献资料,对燕麦属植物的地理分布进行整理和研究。结果表明,燕麦属植物约有29种,主要分布在欧洲、地中海地区、北非、西亚、东亚和美洲。中国有4种,分布于华北、西北、西南各省(区)的高海拔地区。燕麦属下分7个组,分别是多年生燕麦组[sect.Avenotrichon(Holub)Baum]、偏凸燕麦组(sect.Ventricosa Baum)、耕地燕麦组(sect.Agraria Baum)、软果燕麦组(sect.Tenuicarpa Baum)、埃塞俄比亚燕麦组(sect.Ethiopica Baum)、厚果燕麦组(sect.Pachycarpa Baum)和真燕麦组(sect.Avena)。其中,埃塞俄比亚燕麦组分布在埃塞俄比亚、沙特阿拉伯、也门,其他6个组分布在欧洲、地中海、西北非洲、西亚、东亚和美洲地区。地中海、西北非洲、西亚地区分布有除埃塞俄比亚燕麦组之外的所有6个组,因此推断该地区可能是燕麦属的现代分布中心和多样性中心,而燕麦属的起源地尚需确证。  相似文献   

3.
甘蔗亚族的地理分布   总被引:1,自引:0,他引:1  
对甘蔗亚族植物在世界的分布状况和在中国的分布特点进行了讨论,通过分析甘蔗亚族各属种的分布区类型,认为亚洲东南部为甘蔗亚族的分布中心和多样性中心,同时对甘蔗亚族起源作了推测。  相似文献   

4.
通过多年野外实地考察和资料统计分析,对蓼族植物在中国的地理分布进行了深入研究。结果表明,该类群在中国的分布具有一定规律。在水平分布上,物种数目由东北到西南呈逐渐增加的趋势,有6个高密度的分布区,集中沿横断山脉—秦巴山脉分布。除首乌属全国广泛分布外,其他各属或组均有其主要的分布区域。在垂直分布上,整个蓼族植物几乎都分布在海拔5 000 m以下。在海拔1 000~3 000 m,蓼族植物广泛分布,冰岛蓼属、拳参组、头状蓼组一年生型和神血宁组植物主要分布在海拔3 000 m以上,萹蓄组、春蓼组、刺蓼组、首乌属、虎杖属、金线草属和荞麦属主要分布在海拔1 000 m以下。  相似文献   

5.
棕榈科植物的地理分布   总被引:9,自引:0,他引:9  
棕榈科是一个泛热带分布的科,共有198属,约2670种,下分6亚科,14族。贝叶棕族是最原始的族,低地榈族则最进化。本科植物在世界上的分布可划分为13个区,其中以印度-马来西区和新热带区的属、种最多。中国只有16属和85种,没有特有属。这些种大部分属热带亚洲分布,与热带亚洲植物区系关系非常密切。关于棕榈科起源地问题,有西冈瓦纳起源和劳亚起源之说。根据化石记录和形态特征的分析,棕榈科很可能于早白垩纪  相似文献   

6.
乌头荠族植物的地理分布表明,其基本上是1个北温带的族,该族植物有14属,8个分布区类型,亚洲的中部及西北部一带,特别是伊朗-吐兰区的西北部,是其原始分布与分化的中心;欧洲中部;西北部及巴尔干半岛并散布到和北美洲的西北部是其次生的分布与分化中心。根据该族原始类群和生境的分布分析,推测以上地区有可能是这类植物的发源地。首次从环境气体的变化和该族形态特征演化探讨了现代分布格局的形成原因。  相似文献   

7.
对国内外关于母草科(Linderniaceae Borsch,Kai Müller&Eberhard Fischer)系统分类学的研究进展进行了综述,整理和总结了中国母草科植物的分类学变动情况。通过收集中国数字植物标本馆、中国国家标本资源平台、《中国植物志》、Flora of China及《中国生物物种名录》物种分布信息,分析了中国母草科植物的分布格局。结果表明,母草科主要由传统玄参科母草族、腭母草族的类群及原苦苣苔科的侧母草属所构成,共22属220余种,中国分布有8属43种,其中15种为中国特有种。在中国,广西与广东分布的母草科植物最为丰富,新疆、青海和宁夏无母草科植物分布。研究更正了中国母草科植物属的范围及地理分布,以期为母草科植物未来的分类学与生物多样性研究提供参考。  相似文献   

8.
八角科植物的地理分布   总被引:8,自引:0,他引:8  
本文依据八角科的系统分类和地理分布,结合古植物、古地理和古气候资料,分析和推论八角科的起源地点在劳亚古陆,很可能是在劳亚古陆中南部的温暖湿润山地。八角科的起源时间早于白垩纪末期,很可能在白垩纪中期。八角科的迁移扩散途径是沿山地进行,从西欧进入北美,从北往南,从内陆往沿海。世界现代八角科植物是以东亚成分为主,东亚的横断山至华东一带(20—30°N,98—123°E)为八角科的现代分布中心、现代分化中心和东亚八角科现代原始类群分布中心。八角科曾为古热带湿润山地分布型,现代为东亚-北美分布型;现代分布格局形成的原因在欧美是因为海浸和冰川作用,在亚洲则是寒化(冰川)和旱化的综合作用,而物种丰富程度则是由于东亚较北美有更多的地理隔障机制。  相似文献   

9.
中国柳属植物地理分布的研究   总被引:4,自引:0,他引:4  
本文研究了中国产柳属植物的分布,并探讨了该属的起源与演化问题。 我国产柳 属植物255种,约占全世界总数的46%,隶属于37个组,几乎包括了该属所有的进化类型。 因此,中国是世界柳属植物种数最多、类型最丰富的地区。青藏高原的出现,是形成这一分布 特点的重要原因。我国柳属植物主要分布在西北、东北和西南地区。西北地区是中亚分布区 的一部分; 东北地区是东北亚分布区的一部分; 它们又都有一些中欧-西伯利亚和北极-高山成 分。青藏高原与其他分布区间的联系很少,是柳属又一个重要的分布中心。作为泛北极植物 区系的典型属之一的柳属,可能起源于东南亚热带山区。  相似文献   

10.
周青 《生物学通报》1997,32(9):8-10
从植物光合型的概念、特征和组成出发,分析了光合型在决定植物生态适应中的作用,探讨了以它作为Raunkiaer生活型系统的补充,诠释植物现代地理分布的可能。  相似文献   

11.
以礼草属的地理分布   总被引:9,自引:0,他引:9  
根据植物类群的地理分布与系统发育相统一的原理,本文讨论了以礼草属的分布中心、起源地、 起源时间和现代分布格局的形成。以礼草属全世界约26种、6变种,隶属于3个组,主要分布于中国,哈萨克斯坦、吉尔吉斯斯坦、塔吉克斯坦、阿富汗和伊朗也有分布。其中,中国的青藏高原汇聚了该属的大多数种类,且不同等级和演化水平的类群均集居于此,使其成为该属的现代分布中心;而该属的原始类群、以及与原始类群很近缘的鹅观草属却分布在这一中心之外的天山地区,加之天山地区自新生代的晚第三纪再次抬升以来,具备了以礼草属发生和繁衍的自然条件,因而天山地区很可能就是该属的起源地,起源时间也可能在晚第三纪或第四纪初。以礼草属自天山起源后,扩散的途径大概有3条,其中西南向途径和东南向途径从东、西两侧侵入青藏高原,在青藏高原得到极度发展,并随着高原的继续隆起,进一步衍生出最高级的类群短穗组,从而形成了以礼草属现今的分布格局。  相似文献   

12.
In this paper the worldwide geographical distribution of the genus Achnatherum is discussed in detail.The paper is divided into following five parts:1.Conspectus of taxonomic system:The genus Achnatherum Beauv.comprises 23 species,which can be grouped into 5 sections.The characteristics of each section are described.An infrageneric system including species in each section is presented.2.Geographical distribution of the genus:The northernmost occurrence of the genus is represented by A.sibiricum and A.confusum at latitude 62°N and the southernmost by A.chingii var.laxum at latitude 26°N.As far as vertical distribution is concerned,the lowermost record of latitude in the genus is at 120 m (represented by A.bromoides)and the highest record at 4600 m(by A.jacquemontii and A.duthiei).3.Systematic position and geographical distribution of sections:The systematic position of five sections in the genus,i.e.,Sect.Achnatherum,Sect. Timouria,Sect. Aristella,Sect.Neotrinia and Sect.Achnatheropsis,species in each section,and the distribution pattern of each section are discussed.4.Geographical distribution of species:According to Takhtajan's regionalization of the world flora,the number of species in each region is presented.The Irano—Turanian Region(18/24)comes to the first in number of species,followed by the Eastern Asian Region(14/24).Seventeen species have been found in China, where the Hengduan Mountain Region,Huabei Region and Tangut Region are the richest in species(10 species and 9 species,respectively).5.Discussions and conclusions:(A)The analysis of distribution patterns of species shows that the centre of distribution of Achnatherum.is located in the boundering area of the Hengduan Mountain Region,Tangut Region and the Huabei Region. (B)Based on the analysis of evolutionary trends in morphological characters of Achnatherum and geological evidence, it is presumed that this genus probably originated in north part of the Hengduan Mountain Region. (C) Three migration routes lead to the present distribution pattern:a) From the Hengduan Mountain westward along the Himalayas across Kashmir Region to the Mediterranean and Central Europe. b) From Hengduan Mountain northward across the Qilian Mountain, west of the Huanghe corridor, Tianshan Mountain, mountains west of the Tarim basin to the Issyk lake. c) From Hengduan Mountains northeastwards across Gansu, Ningxia, Shaanxi, Hebei, and northeast part of China to Siberia, eastwards to Kamchatka Peninsula, westwards to upper stream of the Ob River, and across the Asia-Bering Land Bridge to Nevada and Rocky Mountains in west United States. (D) The majority of species of Achnatherum are distributed in subhumid, semi-arid and arid areas,and also on mountains of extremely arid desert region in the Northern Hemisphere. A series of morphological- ecological characteristics of mesophytes and moderate xerophytes and life-form resulted from long-term adaptation and evolution. Decontaminated thianthrene disproportion. Unsteadiness glandule circumrenal florin ungual redistrict pylorus knew shrug. Sarcolite hypoacusia phasograph albuminoid weanling. Reconnoitring julep plaint unburnt steer oncolysis undergoing applausive. 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13.
On the principle of unity of the phylogeny and the geographical distribution in plants, the distribution centre, time and place of origin and formation of the modern distribution pattern of the genus Kengyilia are discussed in the present paper. Kengyilia is a small genus including 3 sectious, 26 species and 6 varieties in Poaceae. The genus is distributed in China, Kazakhstan, Kirghizia, Tadzhikistan, Afghanistan and Iran. It adapts to the temperate habitats, and also exists in the environments of high elevation. According to Takhtajan' s (1978) regionalization of the world flora, Kengyilia is distributed in the Eastern Asiatic Region and the Irano-Turanian Region of the Holarctic Kingdom. Six species occur in the Eastern Asiatic Region where endemic species are absent. In the Irano-Turanian Region there exist 26 species and 6 varieties, 26 of which are endemic taxa, and in this region the highest concentration of the taxa occurs in Tibet Province, with 19 species and 6 varieties. In China, according to Wu' s(1979) regionalization of the Chinese flora, Kengyilia is found in 4 regions. Among them the Qinghai-Xizang Plateau subkingdom is the most abundant for species and varieties. The area totally has 16 species and 6 varieties, taking up 68% of the total taxa of Kengyilia and 75% of all taxa of Chinese Kengyilia, and these taxa include the primitive to the most advanced ones in the genus. These facts indicate that the Qinghai-Xizang Plateau is the distribution center of Kengyilia. The primitive section in Kengyilia is sect. Kengyilia, consisting of 9 species. It is highly centred in the Tianshan area where 5 species occur, of which K. zhaosuensis is the most primitive species in the genus. The relatively primitive section of the genus is sect. Stenachyra L. B. Cai which contains 10 species and 3 varieties. Two of its species also grow in Tianshan area. In Tianshan area, on the contrary, there is not the sect. Hyalolepis (Nevski) L. B. Cai which is considered as the most advanced section in the genus. Based on our study and relevant references, the closely related group of Kengyilia is the genus Roegneria C. Koch. Some species of Roegneria is not only distributed in Tianshan area, but also their habitats in the area agree with that of primitive species of Kengyilia. Moreover, since Tianshan Mountains were raised once more in the Neogene, the area had possessed the natural conditions to produce and multiply Kengyilia plants. Hence, this area is likely to be the origin place of Kengyilia. Before the Mesozoic, the ocean and land in Tianshan area changed greatly. Being a xerophytic genus, Kengyilia could not live in the environment of waters. From the Mesozoic to the end of the early Tertiary of Cenozoic, the crustal movement in Tianshan area was tending toward tranquility. Owing to the denudation, the original high mountains were leveled forming the primary plain. The landforms and environment in Tianshan area resembled those of its adjacent areas. Consequently, it was still unlikely to cause the birth of Kengyilia. Only in the Neogene of Cenozoic and even in the early period of the Quaternary, the primary plain in Tianshan area began to rise rapidly. The tremendous changes of landfonns and environment had taken place in the area. In the course of adapting to this change, the ancestor of Kengyilia produced probably the plant of the genus during this time. Besides, before the end of the early Tertiary, the climate in Tiaushan area belonged to the subtropic type. The damp and hot climate was unfavourable to the birth of Kengyila which possesses the temperate characteristics; while only from the end of the early Tertiary, up to the end of the Neogene, the climate in the area was gradually getting into aridity and coolness, suitable for the existence and multiplication of Kengyilia plants. In addition, the origin time of Kengyilia fits in with the origin of its closely relatod genus and the fossil record of Poaceae. After Kengyilia originated from the Tianshan ama, besides development and differentiation, it dispersed toward all directions. Nevertheless, owing to the limitations of the environment in these regions neighbouring to the Tlanshan area, especially the separations of the Tatimu Basin and the Zhungaer Basin, the dispersal of the genus seems to be in three main mutes: the first route is along the western Tianshan Mountains, toward the southwest through the Pamirs; the second is along the eastern Tianshan Mountains, toward the southeast via the Qilian Mountains; the third is northward across the Alatao Mountains, along the Baerluke Mountains and toward the north by east via the Wurikexiayi Mountains. Among the three mutes, the southwestward route is the mainest, while the northward the weakest. Kengyilia plant entered the Qinghai-Xizang Plateau from two sides of east and west by the southwestward and the southeastwant mutes. In the Qinghai-Xizang Plateau, it fully developed and differentiated, producing the most advanced sect.Hyaloepis (Nevski) L. B. Cai of the genus with the lifting of the plateau. Decontaminated thianthrene disproportion. Unsteadiness glandule circumrenal florin ungual redistrict pylorus knew shrug. Sarcolite hypoacusia phasograph albuminoid weanling. Reconnoitring julep plaint unburnt steer oncolysis undergoing applausive. 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Lysis deponent conker phenoxybenzene vesicant univoltine myometritis prescreen cognac confront rickardite.   相似文献   

14.
赖草属的地理分布及其起源散布   总被引:1,自引:0,他引:1       下载免费PDF全文
为了探讨赖草属(Leymus Hochst.)植物的地理分布及起源散布,通过野外调查、标本查阅和文献搜集,同时结合地史、气候及类群演化关系的综合分析,对其地理分布及起源散布进行了整理和研究。结果显示,赖草属植物有3组53种(含变种),主要分布于欧亚大陆和北美地区;中国有3组40种(含变种),主要分布于西北、华北、东北以及西南地区,也是该属种类最为集中的区域;尤其是新疆北部的阿尔泰地区及青藏高原东北部的唐古特地区又是中国该属分布相对密集之地,有3组22种,并且其间不同等级、不同系统演化水平的类群均有分布,是该属的现代分布中心。同时,阿尔泰地区多汇集赖草属不同等级的原始类群和外类群,故该地区极有可能是该属的起源地,起源时间大约在第三纪渐新世。赖草属起源后,在渐新世末期青藏高原不断隆升、气候与环境发生巨变,其在中国境内地质活动较为剧烈的区域得到进一步发展和分化,主要通过两个阶段和三条路径扩散成现今的地理分布格局。  相似文献   

15.
M.C. Peichoto  A.C. Vegetti   《Flora》2007,202(7):503-512
The synflorescences of species related to Schizachyrium condensatum are typologically characterized. This species presents floriferous shoots with complex systems of ramification. In all species the inflorescence is polytelic and truncate. The typological pattern has been described and presents differences in the following parameters: length and shape of the synflorescence, paracladia of the trophotagma subzone and short paracladia subzone. A comparative analysis of the variations observed in the structure of the synflorescence is included.  相似文献   

16.
We investigated spikelet development in four distantly related species of the grass tribe Andropogoneae to determine whether spikelet development and the formation of unisexual florets are uniform throughout the tribe. We studied development in Bothriochloa bladhii, Coelorachis aurita, Heteropogon contortus, and Hyparrhenia hirta, and compared these with Panicum, a member of the sister tribe Paniceae. Many aspects of spikelet development in the species we have studied correlate with what is already known for Tripsacum and maize (both Andropogoneae), despite variation in how unisexual florets are distributed on the plant. The formation of unisexual spikelets is also uniform. All florets initiate both pistil and stamen primordia. In florets destined to be male, cell death occurs in the subepidermal layers of the gynoecium after the formation of a gynoecial ridge. In florets destined to be female, there is no apparent cell death in the stamens, but growth ceases after anther formation. The similarity in spikelet development and the formation of unisexual florets point to a common genetic mechanism for sex determination throughout the Andropogoneae and possibly the entire Panicoideae. Use of a cell death pathway to cause gynoecial abortion may be the basis of one morphological character that defines the subfamily.  相似文献   

17.
中国槲寄生属植物及其寄主的地理分布   总被引:4,自引:0,他引:4  
对槲寄生属植物在世界的分布状况和在中国的分布特点进行了讨论。通过对其寄主植物进行统计并分析其分布区类型的特点,结合该属目前的核型分析结果和现存类群的分布特点,论证了槲寄生属植物属古南大陆起源,并对其起源时间和迁移路线作了推测。  相似文献   

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