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1.
绞股蓝属植物的分类系统和分布 总被引:34,自引:0,他引:34
绞股蓝属全世界有16种2变种,隶属于2亚属2组,即喙果藤亚属(包括五柱绞股蓝组和喙果藤组)及绞股蓝亚属。其现代分布中心或多样化中心为我国长江流域至西南的云南,由此向北达秦岭南坡和淮河流域以南,向东北经华中、华东至朝鲜半岛和日本北部,向南经中南半岛、马来西亚达菲律宾、印度尼西亚诸岛和巴布亚新几内亚,向西达印度西北部,为热带亚洲分布类型。根据该属的原始类群和进化类型的现代分布和多样化中心及它们的生态适应性,与古地质、古地理和古气候的变迁以及外类群起源地等推测,绞股蓝属植物可能与其近缘属——雪胆属和锥形果属共同起源于康滇古陆,起源时间可能为早第三纪。 相似文献
2.
木兰科为亚洲-美洲间断分布科,全世界有15属,246种,主要分布于亚洲东南部的热带、亚热带地区,从喜马拉雅至日本,向南达新几内亚及新不列颠;少数种类分布于北美东南部、中美至南美巴西.中国有11属,约99种.木兰科的现代分布中心在东亚-东南亚地区.根据木兰科的化石记录、系统发育和现代分布,推测其起源时间为早白垩纪,甚至更早.起源地可能在中国的西南地区,并由此向外辐射,向东经日本、俄罗斯远东地区经白令陆桥进入北美;向西经西亚、欧洲,通过格陵兰进入北美,然后到达南美;向南经印度支那、马来西亚,直至新几内亚.东亚-北美间断分布的形成是受第四纪冰期的影响;南美的木兰科是从北美迁移而来. 相似文献
3.
木兰科(Magnoliaceae)的起源、进化和地理分布 总被引:40,自引:1,他引:40
木兰科为亚洲-美洲间断分布科,全世界有15属,246种,主要分布于亚洲东南部的热带、亚热带地区,从喜马拉雅至日本,向南达新几内亚及新不列颠;少数种类分布于北美东南部、中美至南美巴西.中国有11属,约99种.木兰科的现代分布中心在东亚-东南亚地区.根据木兰科的化石记录、系统发育和现代分布,推测其起源时间为早白垩纪,甚至更早.起源地可能在中国的西南地区,并由此向外辐射,向东经日本、俄罗斯远东地区经白令陆桥进入北美;向西经西亚、欧洲,通过格陵兰进入北美,然后到达南美;向南经印度支那、马来西亚,直至新几内亚.东亚-北美间断分布的形成是受第四纪冰期的影响;南美的木兰科是从北美迁移而来. 相似文献
4.
论无心菜属的地理分布 总被引:2,自引:0,他引:2
全世界无心菜属植物有306种,隶属10亚属24组,主要分布于欧、亚、美三洲和北非,基本上是北温带分布属。文章分析了亚属的系统位置及其分布式样。地中海区到西亚亚区和中亚亚区的西北部是其分布区中心,也可能是它的起源地,中国横断山脉到青藏高原是其次生分布中心。起源时间至少应该追溯到白垩纪中期。最后,讨论了它的散布途径和现代分布式样的形成及其原因。 相似文献
5.
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
6.
赖草属的地理分布及其起源散布 总被引:1,自引:0,他引:1
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
7.
CAI Lian-Bing 《植物分类学报:英文版》2001,39(3):248-259
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 ofthe 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 inthe environments of high elevation. According to Takhtajan' s (1978) regionalization of the worldflora, Kengyilia is distributed in the Eastern Asiatic Region and the Irano-Turanian Region of theHolarctic 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 endemictaxa, 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 mostabundant 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 theprimitive 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 whichK. 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 alsogrow 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 studyand 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 wereraised 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 theMesozoic, 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 unlikelyto cause the birth of Kengyilia. Only in the Neogene of Cenozoic and even in the early period of theQuaternary, the primary plain in Tianshan area began to rise rapidly. The tremendous changes oflandfonns 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, beforethe end of the early Tertiary, the climate in Tiaushan area belonged to the subtropic type. The dampand 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 thearea was gradually getting into aridity and coolness, suitable for the existence and multiplication ofKengyilia 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 thelimitations 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 threemain mutes: the first route is along the western Tianshan Mountains, toward the southwest throughthe Pamirs; the second is along the eastern Tianshan Mountains, toward the southeast via the QilianMountains; the third is northward across the Alatao Mountains, along the Baerluke Mountains andtoward the north by east via the Wurikexiayi Mountains. Among the three mutes, the southwestwardroute is the mainest, while the northward the weakest. Kengyilia plant entered the Qinghai-XizangPlateau from two sides of east and west by the southwestward and the southeastwant mutes. In theQinghai-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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8.
The present article is the first comprehensive treatment of phytogeography of Thermopsis(Fabaceae) in the world. Thermopsis is one of the few genera within Fabaceae with the distributionpattern of the East Asia-North American disjunction. The distribution patterns of 5 recognized sections (including a new one) covering 21 species in Thermopsis are analyzed, and the results showfour centres of frequency of the genus: the Eastern Asiatic Region (9 spp. / 3 sects., including 4endemic species), the Irano-Turanian Region (7 spp./3 sects., including 3 endemic species), theRocky Mountain Region (7 spp./2 sects., all endemic), and the Atlantic North American Region(3 spp. / 1 sect., all endemic). In the light of the fact that most species and sections, a number ofphylogenetic series of the genus, and the most primitive sections and most advanced sections inThermopsis occur in the East Asia, the Eastern Asiatic Region might be the centre of diversity of thegenus. As the Irano-Turanian Region and the Rocky Mountain Region were just second to that ofEastern Asiatic Region in number of sections and species, and many polyploids appeared in theseregions, they were considered as the secondary centres of distribution and speciation of the genus.The speciation looks to be frequent and complex in these regions, and many new taxa have been described from there while many new reduced or incorporated taxa have happened over there. However, recent molecular data has shown that two reduced taxa of Thermopsis are distinct in these regions. Based on the modern distribution patterns and evolutionary trends in morphological charactersof the genus, and available fossil record of the genus and the historical geology, we speculate that Thermopsis had already existed on Eurasia and North America before the Late Miocene, and probably originated from an ancestral form of Sophora-like taxa with lupine alkaloids somewhere in theLaurasia in the Early Tertiary or Late Cretaceous. After the separation of the two continents, specieson different continents developed distinctly under influences of different evolutionary factors. InAsia, the late Tertiary orogeny, disappearing of the Tethys and aridity and freezing caused by theQuaternary glaciation were the main forces to promote the speciation and evolutionary processes,whereas in North America it was the Quaternary glaciation and the orogeny of partial area to promoteevolution of the genus. According to the evolutionary trends in Thermopsis and the distribution pattern of the primitive taxa, Sino-Japanese Subregion of Eastern Asiatic Region may be considered asthe centre of primitive forms of Thermopsis. 相似文献
9.
本文报道了禾本科鹅观草属的三个种级新组合和四个变种级新组合。即大丛鹅观草Roegneria magnicaespis (D.F.Cui)L.B.Cai;新疆鹅观草Roegneria sinkiangensis(D.F.Cui)L.B.Cai;阿尔泰鹅观草Roegneria altaica(D.F.Cui)L.B.Cai;短芒鹅观草Roegneria glaberrima var.breviarista (D.F.Cui)L.B.Cai;林缘鹅观草Roegneria mutabilis var.nemoralis (D.F.Cui)L.B.Cai;多花鹅观草Roegneria abolinii var.pluriflora (D.F.Cui)L.B.Cai和曲芒鹅观草Roegneria tschimganica var.glabrispicula (D.F.Cui)L.B.Cai。 相似文献
10.
柽柳科柽柳属的植物地理研究 总被引:7,自引:1,他引:7
柽柳属是典型的旧世界温带分布属。对柽柳属3组68种的分布进行了分析,发现本属3个频度分布中心依次为伊朗—吐兰区的西亚亚区(30种/3组,其中特有种13种),中亚亚区(20种/2组,其中特有种6种)和地中海区(12种/3组,其中特有种6种)。由于伊朗—吐兰地区的西亚亚区存在本属最多的组与种、特有种多且可以见到柽柳属系统发育系列,因而认为该亚区是现存本属植物的现代分布中心和分化中心。地中海地区包含的组、种数仅次于伊朗—吐兰区,并且特有种为6种,带有新特有种的性质,全是系统发育上相对年轻、进步的类型,被认为是本属的一个次级分布中心,另一个次级分布中心在中亚亚区,尤其是中国西北干旱地区。根据柽柳属植物的现代地理分布、化石资料及地质历史资料,推测柽柳属起源于古地中海热带成分盛行的早第三纪始新世,具有起源古老的性质,并且随着晚第三纪古地中海的退缩、气候逐渐干旱而得到进一步发展,产生许多新的以温带成分为主适应旱生环境的现代柽柳属种类。柽柳属起源之后,首先繁衍、散布到以伊朗为中心的现代分布中心,其后以伊朗为廊道向西、向东扩散,在地中海沿岸、东非、阿拉伯半岛、非洲西南部及亚洲中部的荒漠地区得到发展。 相似文献
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豆科黄华属的植物地理研究 总被引:5,自引:0,他引:5
首次全面论述了全世界黄华属(豆科)植物地理。黄华属是豆科少数几个东亚-北美间断分布属之一。对黄华属5组21种的分布进行了分析,发现本属4个频度分布中心依次是:东亚地区(8种/3组,其中特有种4种),伊朗-土兰地区(7种/3组,其中特有种3种),落基山地区(7种/2组,均为特有种)及大西洋北美地区(3种/1组,均为特有种)。基于以下事实:在东亚地区存在本属最多的组与种;在此区可以见到黄华属系统发育系列;该属最原始的组种及最进化的组种也在该区出现等,可以认为东亚地区是该属的现代分布中心及分化中心。伊朗-土兰地区(中亚东部至喜马拉雅)及落基山地区所含种、组数仅次于东亚地区,而且多倍体现象多发生于这两区,因此可认为是本属的次生分布中心及分化中心。在此二地区,物种分化较活跃且复杂,先后描述了很多新种和变种,也曾进行过较多的归并处理。最近的分子生物学证据不断揭示,在这地区曾被归并的一些分类群存在着较大不同,从而提醒分类学家对年轻区系中物种分化较活跃的类群进行分类处理时,无论是建新分类群还是对某些类群进行归并,应持谨慎态度。作者根据黄华属植物的现代地理分布、形态演化趋势、现有的化石及地质历史资料,推测黄华属植物在中新世之前早已形成,并且在晚第三纪欧亚大陆与北美大陆失去陆地连接之前在两大陆已经存在,很可能是于早第三纪或晚白垩纪在劳亚古陆上起源于一个含羽扇豆生物碱的古槐成员。两大陆分离后,在不同的成种因子的影响下,形成了各自的演化格局:在亚洲,晚第三纪的喜马拉雅造山运动、古地中海消失及第四纪冰川作用引起的旱化、寒化,促进了该属植物的强烈分化;而在北美,第四纪的冰川作用及局部的山体隆起,可能是促进该属植物演化的主要动力。根据黄华属植物的系统演化趋势及原始类群的分布式样分析,东亚地区的中国-日本亚区可能是本属植物的原始类型中心。 相似文献
13.
世界杨柳科植物的起源,分化和地理分布 总被引:13,自引:3,他引:13
全世界杨柳科共有650种。分为3属,即钻天柳属、杨属和柳属。花序下垂利于风媒,花序直立利于虫媒。钻天柳属具有利于风媒的雄花序和利于虫媒的雌花序,这是一种进货不完全的现象,是杨柳科中最原始的类群;杨属是杨柳科中适应风媒的分支;柳属是适应虫媒的分支。绝大多数种类分布在北半球温带,是较典型的温带科。其现代分布中分化中心在东亚地区。根据地史资料、化石资料以及杨柳科和其外类群的现代分布情况,我们认为,杨柳科 相似文献
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根据黑穗薹草组植物的外部形态、细胞染色体特征与地理分布之间的关系,结合地质历史事件推测了黑穗薹草组Sect.Racemosae G.Don.的起源、进化和迁移等问题。推测黑穗薹草组可能在早第三纪的始新世起源于我国的喜马拉雅-横断山地区;可能的迁移路径为:由起源中心向北部迁移至欧洲、中亚、俄罗斯西伯利亚地区,并通过格陵兰岛和白令陆桥到达北美洲地区;经过第四纪冰川后,一些分布于北美洲的物种又通过白令陆桥回迁到亚洲东部的俄罗斯远东地区,最终形成该组植物的现代分布格局。 相似文献
16.
Srdjan Bojovic Maja Jurc Dragana Drazic Pavle Pavlovic Miroslava Mitrovic Lola Djurdjevic Richard S. Dodd Zara Afzal-Rafii Marcel Barbero 《Trees - Structure and Function》2005,19(5):531-538
The geographical variation of terpenes of Pinus nigra populations from southwestern Europe was studied. Terpenes from the foliage of 16 populations from Corsica, Herault (France) and the East Pyrenees (France and Spain) were analyzed. A total of 42 terpenes were detected, with -pinene the dominant monoterpene and germacrene-d and caryophyllene the dominant sesquiterpenes. The differences in quantitative content of selected compounds clearly divide populations into two basic geographical groups: on one side the populations from Herault and the East Pyrenees and on the other the populations from Corsica. -Phellandrene and -cadinene have the greatest influence on this global discrimination. Some trees and populations show a similarity although they belong to different geographic locations. The similarity of some trees from Herault and the East Pyrenees and trees from Corsica points to their common origin (Corsica). Our results confirm the hypothesis that the afforestation of Herault and the East Pyrenees was also performed with black pine from Corsica. 相似文献
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本文首次从毛绞股蓝 Gynostemma pubescens(Gagnep.)C.Y,Wu 的茎叶中分得四种黄酮类成分,经理化方法和光谱数据鉴定为:异鼠李素(isorhamnetin),檞皮素(quercetin),异鼠李素-3-0-芸香糖甙(isorhamnetin-3-0-rutinoside)和芦丁(rutin)。 相似文献
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狼洞穴空间格局及生境选择的分析 总被引:4,自引:3,他引:4
内蒙古东部草原地区狼洞穴空间分布格局及其生境选择的聚类分析结果表明,影响狼洞穴分布的主要因子为人类活动干扰和水源距离,其次为隐蔽条件、坡位和坡度,狼选择洞穴的最适生境为陡坡,洞口北向,隐蔽条件中等以上,距人为干扰大于1000m和距水源小于1000m的地方 相似文献
20.
Arthur L. Koch 《Journal of molecular evolution》1985,21(3):270-277
Summary It is proposed that the first entity capable of adaptive Darwinian evolution consisted of a liposome vesicle formed of (1) abiotically produced phospholipidlike molecules; (2) a very few informational macromolecules; and (3) some abiogenic, lipid-soluble, organic molecule serving as a symporter for phosphate and protons and as a means of high-energy-bond generation. The genetic material had functions that led to the production of phospholipidlike materials (leading to growth and division of the primitive cells) and of the carrier needed for energy transduction. It is suggested that the most primitive exploitable energy source was the donation of 2H++2e– at the external face of the primitive cell. The electrons were transferred (by metal impurities) to internal sinks of organic material, thus creating, via a deficit, a protonmotive force that could drive both the active transport of phosphate and high-energy-bond formation.This model implies that proton translocation in a closed-membrane system preceded photochemical or electron transport mechanisms and that chemically transferable metabolic energy was needed at a much earlier stage in the development of life than has usually been assumed. It provides a plausible mechanism whereby cell division of the earliest protocells could have been a spontaneous process powered by the internal development of phospholipids. The stimulus for developing this evolutionary sequence was the realization that cellular life was essential if Darwinian survival of the fittest was to direct evolution toward adaptation to the external environment. 相似文献