鹅观草属的地理分布

鹅观草属是禾本科小麦族中的最大的属,现知全世界有4组,20系,126种,分布于北半球的温带和寒带,中国有4组,18系,79种,主要分布于西北,西南,华北和东北,是鹅观草属植物种类最为集中的区域,尤其高原东北部的唐古特地区又是我国鹅观草属分布相对密集之地,有3组,12系,30种,而且其间不同等级,不同演化水平的类群均有分布,该地可能就是该属的现代分布中心,同时,唐古特地区多汇聚有鹅观草属不同等级的原始类群和与原始类群有很缘的短柄草属植物,其中最原始的大柄鹅观草特产于该区,而该区缺乏的是高级的大颖组类群,故推测唐古特地区可能又是该属的起源地,起源时间大约在青藏高原明显增高,气候转凉的晚第三纪初的中新世,鹅观草属起源后,在中国境内地质活动比较剧烈的地区得到了进一步的发展和分化,但只有少数适应性较强的类群大概以3条路径扩展到国外,并向东到在北美的巴芬岛,向西延伸到大西洋滨岸,向北进入寒冻的北极地区。     

赖草属的地理分布及其起源散布

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。     

獐牙菜属植物的起源, 散布和分布区形成

本文根据植物类群的系统发育和地理分布统一的原理,讨论了獐牙菜属植物的起源、散布和分 布区的形成。獐牙菜属包括11组16系154种,间断分布在亚洲、欧洲、北美洲和非洲。中国西南部- 喜马拉雅地区汇集了大多数种类、不同演化水平的类群以及形形色色的特有类群,成为该属的多样化 中心和多度中心。该属的原始类群和外类群也集中分布在中国西南山地,极有可能是该属的起源地。该 属的分布区类型中出现了各式的间断分布,根据有该属植物分布的大陆间及大陆与岛屿间分离和连接 的时间推测,该属的起源时间至少不会晚于晚白垩纪,也许更早,可追溯到中白垩纪。通过分类群间亲 缘关系和现代分布分析,显示出该属植物从起源地向周围和一定方向散布,形成了三个主要散布途径。在散布过程中植物本身也发生演化和就地特化,形成新的类群。     

中国十字花科(Cruciferae)的地理分布

在评述十字花科（Cruciferae）分类系统,分析主要性状演化趋势和科、属分布的基础上,提出中国十字花科植物可能是本土起源的观点,其起源中心和分布中心可能在以青藏高原为主体的西部高山和丘陵地区,起源时间至少在第三纪晚期以前,并认为中国十字花科植物自起源地（青藏高原）可能有3条主要的散布途径：第1条是自青藏高原向东北部,沿宁夏、陕西、内蒙古、山西、河北,到达东北大小兴安岭一带,并在蒙古高原及东北山地形成次分布中心;第2条自青藏高原向东,经重庆、湖南、湖北,沿长江流域分布,到达东部沿海一带;第3条自青藏高原向东南部,经贵州、广西、广东、福建,延伸到台湾。     

绞股蓝属植物的分类系统和分布

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。     

杜鹃属植物区系的研究

已知世界杜鹃属(Rhododendron)植物约967种（种下分类等级未计算在内）。本文基于植物区系学的观点,讨论了属内8个亚属：常绿杜鹃亚属、杜鹃亚属、马银花亚属、映山红亚属、羊踯躅亚属、云间杜鹃亚属、纯白杜鹃亚属、异蕊杜鹃亚属的系统位置、分布式样。分析了系统发育和地理分布上的时间、空间关系。认为常绿杜鹃亚属和杜鹃亚属是在本属植物起源后的早期阶段就沿不同途径迁徙、繁衍的两个演化枝。自第三纪以来,它们的性状发展多样,种系高度分化。在现存类群中最具原始性状的亚属是常绿杜鹃亚属,这个亚属的云锦杜鹃亚组Subsect.Fortunea,耳叶杜鹃亚组Subsect.Auriculata 保持较多原始性状。种的分布遍及欧洲、北美洲、亚洲、大洋洲(有1种),东亚种类最多,马来西亚次之。中国-喜马拉雅地区既是多度中心又是多样化中心,马来西亚仅是多度中心。大多数种为地方特有性分布,特有现象十分突出,东亚和马来西亚的特有种共约862种,占种总数的89%以上中国有6个亚属(Candidastrum,Mumeazalea不产)约562种,其中特有种约405种。分析第三纪的化石记录,杜鹃属在全球分布的时间、地点,杜鹃属保持原始或古老性状的类群的现代适生地,认为中国西南至中国中部最有可能是杜鹃属植物的起源地,始祖类群起源的时间会是在晚白垩纪至早第三纪。讨论了杜鹃属在第三纪至第四纪向北半球北部的传布,向亚洲西南、亚洲东南和向东亚的传布以及向大洋洲的传布。从杜鹃属在全球传布的现象和途径,看来现代分布格局形成的原因取决于三方面的因素：时间和窨历史对植物繁衍、传播有着重要制约作用,并受制于植物种系自身具有的遗传性和对环境强烈变化的反应能力。     

杉科植物的起源、演化及其分布

本文根据对杉科的系统发育、现代分布和化石分布的研究,结合古地理和古气候资料,讨论了杉科的起源、演化和现代分布格局的成因。杉科基本上是一个亚热带科,我国长江、秦岭以南至华南一带是其现代分布中心。东亚中高纬度的东北地区可能是其起源中心和早期分化中心。起源时间为早侏罗纪或晚三叠纪。杉科植物的各种类型很可能在早白垩纪甚至晚侏罗纪就已分化出来。杉科植物于东亚起源后,在当时劳亚古陆尚未完全解体、气候分带现象尚不甚明显的情况下跨越欧亚大陆散布到北美,并扩散到南半球。自晚白垩纪,白令陆桥和北大西洋陆桥对其在北半球的散布发挥了重要作用。杉科植物目前虽处于衰退状态,但在地质史上却曾经经历过极其繁盛的时代。在中生代中晚期和早第三纪,杉科植物种类繁多,广布于北半球,向北扩散到北极圈内的高纬度地区,是当时的大科。大多数现存属曾分别有过3个或2个分布中心：水松属、落羽杉属和北美红杉属在东亚、北美西部和欧洲;水杉属在东亚和北美西部;柳杉属、杉木属,很可能也包括台湾杉属在东亚和欧洲;巨杉属在欧洲、北美和东亚。在晚白垩纪和第三纪,现存属特别是水松属、落羽杉属、水杉属、北美红杉属和巨杉属,曾是北半球森林植被的重要组成成分。南半球也曾有少量种类,分布亦远较现代普遍。杉科在白垩纪的多样性达到鼎盛,具所有的现代属和大量的化石器官属,但在以后漫长的历史发展过程中,由于地质变迁、气候变化,大量类群绝灭。晚第三纪全球性的气温下降迫使杉科逐渐从高纬度地区撤出。第四纪冰期气候的剧烈恶化使杉科分布区进一步显著退缩至中、低纬度地区,最后在欧洲全部消失,仅在东亚、北美及澳大利亚的少数几个植物 “避难所”中残存下来。现今各属多分布于环太平洋地区极为狭窄的局部范围,在分布区内呈现出孤立或星散的残遗分布式样。杉科现存各属均为古老的孑遗或残遗类群。     

豆科黄华族植物地理学的初步研究

在系统学业伦和地理分布及古植物学资源的基础上,利用形态－地理学的原理和方法,对豆科Papilionaceae黄华族和Tribe Thermopsideae进行了植物地理学的初步研究。结果表明,（１）黄华族可能是古地中海起源的,它的起源地在古北大陆的南岸,大约相当于现在的中纬度地区;（２）起源时间能早于第三纪,大约处白垩纪末和始新世之间。当时有一个所谓的“北热带植物群”Ｂoreotropical Flora发生;（３）本族６个属基本上构成一个比较自然的单元。它们是由原始槐族类祖先演化而来的;（４）木本类是本族原始的,早出的类群,它们基本上处于遗状态;草本类是本族进化的、晚出的类群,们种类多,分布区有扩大的趋势;（５）Ｔhermopsis间断分布于亚洲（包括中亚和东亚）、北美（包括北美东部和北美西部。东亚太平洋沿岸和北美大西洋沿岩最有可能是它的原始保存地,而不是起源地,它们主要是通过古地中海海道而发生联系的,造成原始类群星散分布的格局不是由一次,而是多次地史和气候变化的结果;（６）晚第三纪亚洲腹地造山运动引起的喜马拉雅山的降起和青藏高原的抬升,以及北美落基山山体抬升引起的水温条件的急剧变化是某些类群（包括Piptanthus和Thermopsis)物种局部分化的主要动力。     

川西与藏东南地区杜鹃花属植物及其分布的比较研究

通过青藏高原的川西地区与藏东南地区杜鹃花属植物类群及其数量、地理分布型与垂直分布格局的研究,借助比较生物学的研究方法,揭示这两个重要区域分布的杜鹃花属植物类群及其分布格局的异同。结果表明:青藏高原东部区域的川西地区杜鹃花属植物具有较原始类群多、较高分类等级多、大类群多并与我国东部和狭义横断山联系较广泛的区系特征,类群及其特有种的垂直分布重心较低; 而青藏高原南缘区域的藏东南地区具有较进化类群多、较低分类等级多、小类群多、特化强烈并主要与狭义横断山有较密切联系的区系特征,类群及其特有种的垂直分布重心较高,且两地间近缘类群垂直替代现象明显。有关特征和现象与白垩纪晚期杜鹃花属起源地的温润气候、第三纪渐新世前后高原漫长的渐进抬升和第四纪高原的迅速隆升及其多次冰川的进退等三个地质历史节点和事件具有密切关联并相互对应。从而揭示了在共同的生物地质历史背景下,我国杜鹃花属植物地理区系及其垂直分布特征由东至西的趋异化过程与性质,并据此提出了在幅员广阔的中国—喜玛拉雅这个现代杜鹃花属植物分布中心内,可勾勒出三块具有明显分异的核心分布区,即川西—滇东北区、滇西北—滇西区、藏东南—藏南区。     

甘肃风毛菊属植物区系地理研究及与邻近地区区系的关系

根据对风毛菊属植物野外调查,标本的收集、整理和系统鉴定,该地区风毛菊属植物共有57种1变种,隶属于4亚属,在甘肃省有2个分布丰富区:青藏高原东、北缘的甘南地区和祁连山地。分析表明,风毛菊属植物是一个北温带分布的属,可划为5个分布型和2个变型,其中以中国特有、横断山脉—喜马拉雅分布最多(分别占36%和29.5%),特有属为新特有属,说明该区系属于一个年轻的、以横断山脉—喜马拉雅分布为主的温带性质,并与青藏高原、中亚地区有密切联系;喜马拉雅、横断山区是风毛菊属植物的现代分布中心和分化中心,华北、华中地区是一个次生分布中心;菊科在古地中海地区于第三纪的早、中期得到分化与发展,其中原始的帚木菊族向西南亚迁移时分化、衍生出原始的菜蓟族的祖先种,该族在大约第三纪从起源中心向中亚干旱地区分化出风毛菊属植物,因此,该区系起源于第三纪的中亚至喜马拉雅一带;青藏高原的隆起、海浸海退,使属内种类剧烈分化,第三纪、第四纪北半球冰期、间冰期交替作用,使本区系向亚洲温暖地区迁移,并进一步发展,形成了现今的区系成分。     

Geographical distribution of Kengyilia Yen et J. L. Yang (Poaceae)

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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A taxonomical study on the genus Kengyilia Yen et J. L. Yang

Kengyilia Yen et J L Yang is a recently established genus in trib. Tritieeae of Poaceae. In this paper, this genus is taxonomically revised, and a new taxonomic system is presented. The new system includes 3 sections, 26 species and 6 varieties, of which 3 sections and 1 species are described as new, 7 taxa are treated respectively in the ways of new status or combination and reduction. Three new sections, sect. Kengyilia, sect. Stenachyra L. B. Cai and sect. Hyalolepis (Nevski) L. B. Cai, are differentiated by the length and width of spike, the growing position of spikelet, the relative length of glume, the colour of anther and so on. The sect. Kengyilia contains 9 species, distributed in northwestern China, extending westward to Kazakhstan, Kirghizia, Tadzhikistan, Afghanistan and Iran; the sect. Stenachyra L. B. Cai comprises 10 species and 3 verieties, distributed in western China, mainly in the Qinghai-Xizang Plateau; and the sect. Hyalolepis (Nevski) L. B. Cai consists of about 7 species and 3 varieties, distributed in western China, extending westward to Kirghizia and Tadzhikistan. Twenty-six species of Kengyilia are recognized on the basis of the same criterion of specific concept, and the other taxa below the rank of species are also checked in terms of their external morphology. As a result, Kengyilia pen~ dula L. B. Cai is reported as a new species; K. hirsuta var. obviaristata L. B. Cai is raised to a species; K. melanthera (Keng) J. L. Yang, Yen et Baum is reduced to a variety under K. thoroldiana (Oliver) J. L. Yang, Yen et Baum; Roegneria hirsuta var. leiophylla Keng et S. L. Chen is reduced as a synonym of K. hirsuta var. hirsuta; Agropyron thoroldianum var. lasciusculum Melderis is reduced to K. grandiglumis (Keng et S. L. Chen) J. L. Yang, Yen et Baum; Roegneria rigidula var. intermedia Keng et S. L. Chen to K. rigidula (Keng et S. L. Chen) J. L. Yang, Yen et Baum; R. hirsuta var. variabilis Keng et S. L. Chen and R. rnelanthera var. tahopaica Keng et S. L. Chen to K. hirsuta (Keng et S. L. Chen)J. L. Yang, Yen et Baum. In addition, new records onthe geographical distributions of some taxa are also reported in this paper.     

以礼草属的分类研究

以礼草属Kengyilia Yen et J. L. Yang 是禾本科Poaceae小麦族trib．Triticeae中新近建立的屑,针对其存在问题,对它进行了全面清理,提出了一个新的分类系统。新系统含3组、26种、6变种,其中3个组为新设立,并包括1新种、7个新等级、新组合及新异名。此外,还报道了一些类群的分布新记录。     

嵩草属地理分布的研究

嵩草属Kobresia Willd.隶属于莎草科,全世界有64种5变种,中国有49种4变种,属下分为4个组。该属主要分布于北半球温带至寒带,亚洲种类最多,主要集中分布于喜马拉雅山地区和横断山地区。上述两地共有总数的90％以上的种类。因此,喜马拉雅-横断山地区为嵩草属的分布中心。与嵩草属最近缘的属Schoenoxiphium只分布在马达加斯加和非洲东南部山地。两个属可能有共同的祖先,发生于冈瓦纳古陆。随着印度板块与非洲大陆分离并向北方漂移,嵩草属的祖先被带到欧亚大陆,在两个板块相遇处——喜马拉雅-横断山地区产生了现在的嵩草属。其后,喜马拉雅山脉进一步抬升,气候与环境发生巨变,嵩草属也进一步分化形成现在的规模。印度板块在早第三纪与欧亚大陆相连接,嵩草属可能就是此时起源于喜马拉雅山地区,并开始分化,且沿北半球的山系向北扩散到欧洲和西伯利亚,又从欧洲到格陵兰再到加拿大东部,从西伯利亚通过白令海峡到阿拉斯加并沿落基山脉南下达到美国的科罗拉多,形成了嵩草属现今的分布格局。     

The phytogeographical studies of Thermopsis (Fabaceae)

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 distribution pattern 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 show four centres of frequency of the genus: the Eastern Asiatic Region (9 spp. / 3 sects., including 4 endemic species), the Irano-Turanian Region (7 spp./3 sects., including 3 endemic species), the Rocky 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 of phylogenetic series of the genus, and the most primitive sections and most advanced sections in Thermopsis occur in the East Asia, the Eastern Asiatic Region might be the centre of diversity of the genus. As the Irano-Turanian Region and the Rocky Mountain Region were just second to that of Eastern Asiatic Region in number of sections and species, and many polyploids appeared in these regions, 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 characters of 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 the Laurasia in the Early Tertiary or Late Cretaceous. After the separation of the two continents, species on different continents developed distinctly under influences of different evolutionary factors. In Asia, the late Tertiary orogeny, disappearing of the Tethys and aridity and freezing caused by the Quaternary 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 promote evolution 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.     

四川贡嘎山地区杜鹃属的地理分布及区系组成

贡嘎山地区位于青藏高原的东南缘,横断山系的东北段,现有杜鹃属植物73种4变种2亚种。在贡嘎山地区东坡的不同垂直高度上分布有43种(包括变、亚种)杜鹃,西坡则分布有63种(包括变、亚种)。贡嘎山地区杜鹃属植物的区系组成属于泛北极植物区,大致分为:1、中国-日本森林植物亚区,只有1种杜鹃。2、中国-喜马拉雅森林植物亚区,有78种(包括4变种, 2亚种),其中(1)1种分布于西藏、云南,并经云南入缅甸分布;(2)44种为四川特产;(3)5种为贡嘎山地区特有种。另外,贡嘎山地区杜鹃属植物区系还有其特点:1、贡嘎山地区是杜鹃属植物分布中心之一;2、贡嘎山地区是杜鹃属植物分化中心之一;3、贡嘎山地区杜鹃属植物有垂直替代现象。     

横断山脉地区蒲公英属植物资料

对我国横断山脉地区的蒲公英属植物进行了总结,收载了该地区产的18种蒲公英属植物。     

一种改进的PAE方法及其在锦鸡儿组(锦鸡儿属)特有性分析中的应用

针对特有性简约性分析（PAE）不足之处,提出一个新的改进分析方法。主要区别是,新方法对分布区内分类群区分了原始和演化,相应地编码为0／1;为了获取分类群原始和演化的特性,分析以分类群分支图为基础。新方法是系统发育与地理分布相统一原理的一个具体的定量化探讨。用新方法分析了豆科锦鸡儿属锦鸡儿组15种,结果表明新方法优于以前的PAE方法。用新的改进方法分析得到的可能的祖先分布区是原始类群树锦鸡儿和一大类属内原始类群的分布区。与目前属的起源问题的一般观点相一致。     

鹅观草属部分种的叶表皮微形态特征及其分类学意义

在过去叶表皮实验的基础上 ,本文从鹅观草属不同组、系中新增解剖了 1 6个有代表性的种。根据这些种叶片反映的表皮微形态特征 ,进一步证实了鹅观草属共族分属以及属下类群划分的正确性 ,揭示了属中各主要类群的演化水平和系统发育关系。研究结果最后表明 :鹅观草属的半颖组最原始 ,在系统发育中它可能既派生了较进化的小颖组和大颖组 ,又派生了最进化的长颖组 ;在大颖组中 ,齿草系较原始 ,纤毛草系较进化 ,宽叶草系最进化 ,纤毛草系和宽叶草系可能相继起生于齿草系。并且 ,鹅观草属的这种进化关系同过去细胞学和形态学提供的证据是基本一致的。     

青藏高原东北部植物染色体数目和多倍性研究

对青藏高原东北高山冰缘地区和相邻低海拔地区５９种多年生草本被子植物进行了染色体计数。其中,４５个种的染色体记数为首次报道,并确定其倍性。对分布于高山冰缘地区和冰缘以下不同海拔地区植物染色体的多倍性进行分析研究。