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1.
青藏高原和喜马拉雅地区锦鸡儿属植物的地理分布   总被引:9,自引:0,他引:9  
锦鸡儿属Caragana是一个典型的温带亚洲分布属。本属在青藏高原和喜马拉雅约有24种1变种,约占整个属的1/3。这些种类几乎全部处于演化高级阶段,且既有叶轴宿存类群,也有假掌状叶类群。反映出种的分化很活跃,在横断山地区形成本属的分布中心、分化中心。本区内绝大多数种类是特有分布。替代现象主要受气候、植被变化作用,沿横断山和喜马拉雅分布的长齿系Ser. Bracteolatae Kom.是一个典型的替代分布类群。锦鸡儿属植物生态适应性很强,可在其生长的灌丛中形成优势种。 寒化和旱化现象十分突出,它们有一系列森林种、草原种和荒漠种及相关的形态变异。用锦鸡儿属植物进行青藏高原和喜马拉雅区域内的分布区关系分析及最小生成树MST和特有性简约性分析(PAE),表明横断山地区特别是其北部是本属植物的一个地理结点。以此沿横断山向北部唐古特和西部藏东南适应性辐射。横断山和西喜马拉雅联系微弱,看不出植物长距离扩散的踪迹,大多是由于生态因子限制而产生的隔离。虽然本区不可能是锦鸡儿属的起源地,然而,通过本区与邻近地区的地理联系,可推测它们在我国适应性辐射方向是从东北向西南。结合豆科蝶形花亚科其它属化石记录及其分布区局限在温带亚洲等现象,认为锦鸡儿植物是一组特化、晚近衍生的类群,起源于北方东西伯利亚晚第三纪中新世后期至上新世。  相似文献   

2.
中国水柏枝属的分类研究   总被引:11,自引:0,他引:11  
水柏枝属Myricaria Desv.最早属于柽柳属Tamarix的范畴。C.Linnaeus于1753年在《植物种志》中首先记载了产于欧洲(德国)的一种水柏枝,即置于柽柳属内,为Tamarix germanica L.(10)。  相似文献   

3.
The Xizang (Tibetan) flora with numerous endemics is of importance in Chinese flora. According to recent statistics there are in Xizang 27 genera of spermatophytes endemic to China, being only 2.25% percent of the total number of genera in the Xizang flora. Four of them are regarded as palaeoendemics (14.81%) and the others as neoendemics (85.19%). These endemic genera, of 30 species and 3 varieties, belong to 17 families, of which, Umbelliferae contains 6 genera, 7 species and 3 varieties; Compositae has 6 genera and 7 species, and Gentianaceae 1 genus and 2 species. All the other families each comprises one genus with a single species. The cosmopolitan families together comprising 14 genera with 15 species have the highest perecentage (52.92%) and the tropical ones (5 families, 5 genera with 5 species) come to the next (29.42%), followed by the temperate ones (3 families, 10 genera with 10 species) (17.66%). It shows that these endemic genera are obviously related to the tropical flora and temperate one in essence. According to the number of species, the genera endemic to China and occurring in Xizang flora may be grouped as fallows. Monotypic endemic ones 14 (51.85%) Ditypic endemic ones 6 (22.22%) Oligotypic endemic ones 4 (14.81%) Small endemic ones 3 (11.11%) The formation of the endemic genera is correlated with the topography, climate and environmental conditions, and they may have resulted from the diversification in geography and climatic influence for a long time. The southeastern part of Xizang Plateau is of very diverse ecological conditions, with the adequate precipitation, which may explain the concentration of these endemic genera in this region. The largest similarity coefficient (38.30%) of the genera endemic to China and occurring in Xizang is with those in Qinghai Plateau, next, with those in Yunnan and in Sichuan provinces (both 27.60%), which shows that these endemic genera are related to the floras of the regions mentioned above. The difference in the horizontal distribution of these endemic genera is obviously between the southern and northern parts of Xizang Plateau. The vertical distribution of the genera is also rather obvious, from 800 m to 5200 m above sea level, but concentrated in the zone of 3000 m to 4500 mm. Therefore their occurrence in Xizang is not only affected by the historical environmental conditions but also controlled by the horizontal and vertical distribution. The origin and evolution of some endemic genera, such as Psammosilene, Parateropyrum, Sphaerotylos, Salweenia, Ajaniopsis, Xizangia, Sinoleontopodium, are discussed in this paper. Parateropyrum, a monotypic palaeotropic endemic, belongs to the tribe Atraphaxideae including Atraphaxis, Calligonum and Pteropyrum. It may be a comparatively advanced group in the tribe, and is closely related to the genus Pteropyrum which is distributed in western Asia. The genus Parapteropyrum has possibly survived as a palaetropic-tertiary relic in this region. Sphaerotylos, a member of the subtribe Sphaerotylinae, the tribe Boehmerieae in the family Urticaceae, is a comparatively primitive genus in the tribe Boehmerieae so far known. As the other subtribes, such as Boehmerinae, Sarconchlamydinae, Orecnidinae and Maoutinae, are distributed in the tropics, rarely in the subtropics, the genus is no doubt a palaetropic -tertiary relic. Sinoleontopodium, belonging to the tribe lnuleae in Compositae, is also related to the genus Leontopodium. It is probable that the genus Sinoleontopodium arised later than the other. We come to the conclusion that the southern part of Xizang Plateau is also one of thecentres of the origin and differentiation of genera endemic to China.  相似文献   

4.
青藏高原跳甲亚科昆虫区系研究   总被引:3,自引:0,他引:3  
讨论青藏高原(包括横断山区)的跳甲亚科昆虫区系。该区已知47属228种。1)据属级阶元的分布类型分析,以东洋属和南型属种显占优势,是区系主体,显示该区跳甲区系的热带渊源,其中高山属种赋予该区以高山区系特征;2)该区物种分化活跃,是某些多种属中国种类的分布中心和分化中心;3)联系中国跳甲亚科区系,在地理分布格局上显示西-东分布,如Hespera属的分布和西南-东北分布或西南-东北的间断分布格局,如Pentamesa和Stenoluperus属的分布。这种地理分布格局反映青藏高原的隆起给中国昆虫区系带来重要影响。  相似文献   

5.
Shre.  KK 《植物分类学报》1997,35(5):396-433
Cyananthus Wallich ex Bentham, the only genus of Campanulaceae with superior ovary, is revised to clarify infrageneric relationships and phylogeny of the genus. Evidence obtained from the comparative gross morphology, anatomy, palynology, and karyomorpho-logy recommends a new infrageneric classification of the genus, recognizing 23 species, belonging to two subgenera, four sections and four subsections. One subgenus(Subgen. Mi-cranthus), one section(Sect. Suffruticulosi) and two subsections(Subsect. Flavi and Sub-sect. Lichiangenses)are described as new taxa. New combinations at sectional (Sect. Annui) and subsectional(Subsect. Stenolobi) ranks are also proposed. The genus Cyananthus is strictly distributed in the high mountains of China(Xizang, Yunnan and Sichuan), extending to Bhutan, Nepal and India (Kumaon-Garhwal, Assam and Sikkim), with altitudinal ranges from 2500 ~ 5300 m. It is observed that 13 species are endemic to SW China and only three species are endemic to the Himalayas( two species in Ne  相似文献   

6.
嵩草属地理分布的研究   总被引:8,自引:0,他引:8  
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。  相似文献   

7.
The geographical distribution maps of the subgenus Pogonophace (Fabaceae: Astragalus) in China were designed and drawn using GIS cartographic technique. The species of the subgenus and county of China were treated as the basic composition units in the GIS cartographic technique. Most of the distribution maps were shown in spots. The distribution pattern of the subgenus illustrates that it is a peculiar group to adapt the cold alpine environment and distribute mainly in Hengduan Mountains and Himalayas. According to the geographical distribution maps and some statistic analyses, Hengduan Mountains region is suggested to be the distribution center, differentiation center and endemic center of the subgenus. Some vicariance traces at levels of the species or sections are very interesting among the distribution patterns of the subgenus and shown clearly in the maps.  相似文献   

8.
There have been few studies of the alpine subnival belt flora in the Hengduan Mountains (HM), which host remarkable biodiversity. To extend knowledge of this flora, we examined published florae, herbarium specimens, and field observations (and material) collected by both ourselves and others. In total, 942 seed plant species have been recorded in the belt, representing 168 genera and 48 families. Twenty-four large families (with ≥10 species) are present, represented by 873 species (92.68% of the total). These include Asteraceae, Saxifragaceae, and Brassicaceae (146, 82, and 71 species, respectively). There are also 27 large genera (represented by ≥10 species), collectively contributing 587 species (62.31%) to the flora, including Saxifraga, Corydalis, and Saussurea (75, 55, and 49 species, respectively). Areal elements represented by the highest numbers of genera are the North temperate, Sino-Himalaya, and Old World temperate elements (39.88%, 14.29%, and 12.50%, respectively), while the Hengduan Mountains, Sino-Himalaya, and Qinghai-Tibetan Plateau elements are most species-rich (355, 281, and 161 species, respectively), collectively accounting for 84.61% species of the known flora. Of these, 295 species (31.32%) are endemic to the Sino-Himalayan alpine subnival belt and 151 (16.03%) strictly endemic to the alpine subnival belt of the HM. These findings indicate that the flora is young, strongly differentiated, probably developed as a result of the plateau's uplift, and speciation has been accelerated by the harsh environment and strong heterogeneity of niches.  相似文献   

9.
胡亮 《生物多样性》2016,24(10):1105-104
喜马拉雅山地是生物地理学研究的热点地区之一。本文对喜马拉雅地区的藤本植物多样性及其与毗邻地区的联系进行了统计分析, 并对该地区与印度河-恒河平原地区藤本植物多样性的地理格局及其成因进行了研究。结果显示: (1)喜马拉雅地区总计有1,083种藤本植物, 分属72科309属; 其中木质藤本725种, 草质藤本358种; 攀援方式主要为缠绕攀援(51.3%)。(2)该区域的藤本植物组成受相邻区域植物区系的显著影响, 其1,083种藤本植物中有74.1% (802种)在东南亚地区有分布, 50.6% (548种)在南亚有分布, 48.9% (530种)在中国西南地区有分布。本区藤本植物缺乏特有性, 仅125种(11.5%)为本区所特有, 没有特有含藤属。(3)藤本植物多样性及其在植物区系中的比例均自东向西逐渐降低; 木质藤本比例和缠绕攀援藤本比例均自东向西略呈上升趋势; 大多数含藤属的藤本多样性由东往西递减, 仅极少数含藤属由东往西逐渐增加, 如野豌豆属(Vicia)和菟丝子属(Cuscuta)。(4)藤本植物多样性在喜马拉雅和印度河-恒河平原地区呈现出自东向西递减的相似格局, 由东往西方向上含藤属递减率分别为8.4属/100 km和6.3属/100 km, 但喜马拉雅地区藤本植物多样性更高。喜马拉雅和印度河-恒河平原地区均有分布的272个含藤属中有196属在中亚及伊朗高原不再有分布, 其中31.1% (61属)在喜马拉雅地区的分布显著更偏西, 仅4.1% (8属)在印度河-恒河平原的分布显著更偏西。综合分析表明, 喜马拉雅地区藤本植物的多样性及其地理格局的特点与其特殊的地理位置、气候条件和生境的梯度变化以及毗邻地区植物区系的多元化有关; 水分条件的东西向梯度变化可能是藤本植物在喜马拉雅和印度河-恒河平原地区形成相似格局的主要原因。  相似文献   

10.
The Rosaceae is one of the five largest families of Xizang flora, consisting of 30 genera with 242 species, the total number of species is slightly less than those of Compositae, Graminae, Leguminosae and Ericaceae in Xizang, amounting to 62.5% of the total number of genera and 28% of the total number of species of the rosaceous flora in China. The four subfamilies of Rosaceae including primitive, intermediate and advanced groups have been found in Xizang. These groups consist of 11 types of floristic elements, i.e. 4 genera belong to cosmopolitan, 9 genera belong to North Temperate, 3, E. Asian-N. American, 3 Sino-Himalayan, 3 Sino-Japanesa, 2 Old World Temperate, 1 Temperate Asian, 2 Mediterranean-W. and O. Asian, 1 C. Asian, I Tropical Asian and 1 endemic to China. It is obvious that Rosaceae in Xizang comprises holarctic, Ancient Mediterranean and paleotropical elements, among which the temperate components are the most dominant. The characteristics of the floristic composition of Rosaceae in Xizang may be summarized as follows: (1) Xizang abounds in both genera and species of the family which are diverse in forms, including the primitive, intermediate and advanced groups, (2) The geographical elements are rather complex, mostly belonging to the temperate, among which the Sino- Himalayan components and the elements endemic to China are dominant, (3) The proportion of plants endemic to China and distributed in Xizang is much higher than those endemic to Xizang itself, but there exist newly arisen species and infraspecific forms or varieties which show that the speciation is apparently still active in Xizang. The rosaceous flora of Xizang is a combination of old and new floristic elements, based on the old floristic components, affected by the upheaval of the Himalayas, the differentiation and speciation have been taking place in the long history. The geographical distribution of Rosaceae in Xizang may be divided into 5 regions, i.e. the northeastern, southeastern, southern, northwestern and northern. The rosaceous plants are most abundant in the southeastern area, next in southern area, fewer in the northeastern and very rare in the northwestern and northern regions. The general tendency of the distribution of Rosaceae in Xizang is that the number of species gradually decreases from the southeast to the northwest and the habit gradually changes from trees, shrubs and herbaceous plants in the southeast to cushion-like scrubs and dwarf perennial herbs in the northwest. These facts clearly show that the uplift of the Himalayas has deeply affected the phytogeographical distribution of Xizang Rosaceae. The rosaceous flora of Xizang has close relationships with those of the adjoring regions, i.e. Yunnan and Sichuan. Besides, it is connected with floras of Nepal, Sikkim, Bhutan nothern Buram and nothern India, but silghtly influenced by the Ancient Mediterranean flora.  相似文献   

11.
色季拉山区高寒山地植物的生态特征   总被引:2,自引:0,他引:2  
通过野外调查和现有文献资料,分析了色季拉山高寒地带植物的构成特征,结果表明:该区有种子植物33科103属285种,其中双子叶植物有26科77属236种,裸子植物有1科1属4种,中国特有植物125种,占总种数的44.01%,西藏特有植物53种,占18.66%。在整个高山寒带中,草本有239种,占83.86%,其中多年生草本230种。植被区系组成、群落植物生活型和叶的性质等特征总体都反映了植被的温带性质。并阐述了该区高山植物对高山恶劣气候环境相适应的形态结构特征。  相似文献   

12.
The Hengduan Mountain Region on the south-eastern fringe of the Qinghai- Xizang (Tibet) Plateau is located in W. Sichuan, N. W. Yunnan and E. Xizang, with a wide area of juxtaposition from the east to the west, the mountains extending and the rivers flowing from the north to the south. In this paper it covers an area from Daojie, Wayao, Yingping, Yangbi, Dali of Yunnan and Dukou of Sichuan in the south, to Banbar, Dengqeu, Shenda of Tibet and Serxu, Dainkog, Shuajingsi and Nanping (Jiuzhaigou) of Sichuan in the north, and from Lharong, Baxoi and Zayü of Tibet in the west, to Maowen, Wenchuan, Mt. Erlang, Mt. Emei and Xichang of Sichuan in the east (Fig. 1.). The Gongga Mountain is the highest in the region, its summit being at an altitude of 7556m, whereas the Dadu River Valley in the eastern part of the area is only 1150 m above sea level. Therefore, the relative height is about 6400 m in the region. The Hengduan Mountain Region is well-known for its various topography, complex natural conditions and rich flora. The floristic composition and features of orchids in Hengduan Mountain Region. 1. The species of orchids are abundant in the region. As we know so far, orchids in the Hengduan Mountain Region comprise 91 genera and 363 species with 9 varieties, and thus it is one of concentration centres of orchids in China, making up 56.17% of the total number of orchids genera in China, only less than in Yunnan and Taiwan, and 34.87% of the total number of orchids species in China, only less than in Yunnan and Sichuan. 2. The orchids genera in the Hengduan Mountain Region are complex in geographical components as indicated below: (1) Four geneva are endemic to China and one of them is endemic to the region. (2) Fourteen genera are of the north temperate distribution pattern, 2 of the Old World temperate one, 18 of the East-Asian one (including Sino-Himalayan and Sino-Japanese) and 3 of the East-Asian-North American one. (3) Twenty one genera belong to the tropical Asian distribution pattern, 3 to the tropical Asian-tropical African one, 13 to the tropical Asian-tropical Australian one, 1 to the tropical Asian-tropical South American one, 8 to the Old World tropical one and 2 to the pantropical one. (4) Two genera are cosmopolitan. The analysis of genera: Fourty eight genera (containing 151 species with 4 varieties) of the tropical distribution occur in the region, among which Calanthe and Cymbidium distributed in the temperate region, and Bulbophyllum and Peristylus in the subtropical part of China are comparatively abundant (with over 10 species), but the other 25 genera are monospecific and 11 genera each contain only 2-3 species. Some epiphytic genera mainly distributed in tropical Asia and belonging to tropical florestic elements, such as Vanda, Luisia, Schoenorchis, Flickingeria, Monomeria, Kingidium, Acampe, Phalaenopsis, Thrixspermum, Eria, Taeniophyllum, and terrestrial genera, such as Aphyllorchis, Collabium, Mischobulbum, Paphiopedilum, Thunia, Brachycarythis, Satyrium, Corybas, Geodorum, Zeuxine, Tropidia, have the Hengduan Mountain Region as the northern limit of distribution. Of 151 species with 4 varieties, 41 species with 4 varieties are endemic to China, and 14 species with 3 varieties of them are endemic to the area, making up 3.86% of the total in the region under discussion. There are 41 genera (containing 189 species with 5 varieties) of the temperate distribution, which occur in the region. Among them Platanthera (22 species with 1 variety), Cypripedium (17 species), Herminium (16 species), Amitostigma (15 species with 1 variety), Orchis (12 species), Hemipilia (8 species with 1 variety), Neottianthe (4 species), Gymnadenia (4 species), Diphylax (3 species), Bletilla (3 species), have the Hengduan Mountain Region as the distribution centre and differentiation centre. Among the 189 species with 5 varieties, 111 species with 5 varieties are endemic to China, and 54 species with 5 varieties are endemic to the area, making up 14.88% of the total of orchids in the Hengduan Mountain Region. Although the number of temperate distribution genera is smaller than that of tropical distribution ones, several points may be mentioned: (1) The Hengduan Mountain Region is distribution centre and differentiation centre of a number of temperate genera in China, and is the northern limit of many genera mainly distributed in the tropics. (2) The number in the former category is obviously larger than that in the latter. (3) Endemic species in the former category in the area are over three times as many as those in the latter. The differentiation of species of the temperate distribution genera is obviously stronger than the tropical ones, which characterizes the orchid flora in the area as the temperate one. The life forms of genera. The orchid flora in the Hengduan Mountain Region so far known comprises 91 genera, among which 51 are terrestrial, 32 epiphytic and 8 saprophytic, thus with the terrestrial one dominant. The analysis of species: The orchid flora in the Hengduan Mountain Region so far known comprises 363 species with 9 varieties. Their distribution patterns and floristic components, to which they belong, are indicated as follows: (1) Fifty four species, belonging to 33 genera, are widespread, covering the whole East Asian Region, but 6 of them are endemic to China. (2) Forty four species, belonging to 27 genera, are the elements of the Sino-Japanese Subregion, but 22 species of them are endemic to China. (3) One hundred and ninety five species with nine varieties, belonging to 53 genera, are the elements of the Sino-Himalayan Subregion under discussion: (A) Four species (i.e. Aphyllorchis alpine, Listera divaricata, L. pinetorum and Oreorchis micrantha) are distributed in the Himalayan Region and S. E. Xizang (Tibet), western part of this region. (B) Twenty five species, belonging to 17 genera, are distributed in N. W. Yunnan and the Himalayan Region (Appendix, 1.). (C) Sixteen species, belonging to 11 genera, are distributed in the Himalayan region and W. Sichuan. Among them 6 species occur only with Mt. Emei as the easternmost limit and 10 species occur in the region west of Mt. Emei. (D) Ten species, belonging to 9 genera, are distributed in the Himalayan region, this region and S. Shaanxi, S. Gansu or S. E. Qinghai. (E) Eight species, belonging to 6 genera, are distributed in the Himalayan region and this region. Among them 6 species have their range extending eastwards to Guizhou and 2 species eastwards to Guangxi. (F) Five species, belonging to 5 genera, having their range extending from this region southwards to N. Burma. (G) One handred and twenty seven species with nine varieties are endemic to China behind discussion. (4) (A) Three species (i.e. Anoectochilus moulmeinensis, Bulbophyllum forrestii and Liparis chapaensis) are distributed in Indo-China, Burma and the region. (B) Nine species, belonging to 7 genera, are distributed in Indo-China, N. E. India and this region. (C) Forty six species, belonging to 21 genera, are distributed in Indo-China, the Himalayan Region and this region (Appendix, 2.). (D) Twelve species, belonging to 11 genera, are distributed in Indo-China and this region (Appendix, 3.) 3. The vicarism is obvious in the orchid flora of the Hengduan Mountain Region. There are 10 species-pairs (in genera Calanthe, Tropidia, Anoectochilus, Mischobulbum, Bulbophyllum, Gymnadenia, Pogonia, Tipularia, Tulotis, Orchis, etc.) of the horizontal vicarism and 7 species-pairs (in genera Epigeneium, Epipogium, Platanthera, Pogonia, etc.) of the vertical vicarism in the region. 4. The endemic species are prolific in the region. In the orchid flora of the Hengduan Mountain Region there are 155 species and 9 varieties endemic to China: (1) Six species are widespread in the whole East-Asian Region. (2) Twenty two species are the elements of the Sino-Japanese Subregion. (3) One hundred and twenty seven species with nine varieties are the elements of the Sino-Himalayan Subregion. Among them 69 species with 5 varieties are endemic to the region (Appendix, 4.), making up 19% of the total in the region; other 58 species with 4 varieties are distributed in the region and neighbouring regions or provinces of it (Appendix, 5.). 5. Remarkable differentiation of the orchid flora in the Hengduan Mountain Region is shown by evident vicarism and abundance of endemic elements, exampled by Amitostigma, Herminium, Orchis, Cypripedium, Platanthera, etc. and one group of Platanthera, which is confined to the south fringe of the Xizang (Tibet) Plateau-Hengduan Mountain Region. The group consists of 12 species, of which one (P. edgeworthii) is distributed in the Western Himalayas from Hazara in Pakistan to Kumaun in India, and all the other 11 species (i.e.P. stenantha, P. bakeriana, P. roseotincta, P. deflexilabella, P. longiglandula, P. exilliana, P. chiloglossa, P. leptocaulon, P. platantheroides, P. clavigera and P. latilabris) occur in China, with 3 of them (i.e.P. deflexilabella, P. longiglandula and P. chiloglossa) endemic to China. According to their structure of gynostemum and form of labellum they belong to Platanthera without question, although they are different from the other members of Platanthera in stigma convex (not concave) and sepals mammillary-ciliate, stigma exhibits a series of evolutionary trends in part of species, from stigma single, convex, elliptic and located near rear of spur mouth (in P. stenantha) to stigma single, suddle, and located near front of spur mouth (in P. bakeriana) and to stigma double, separate and located at front of spur mouth in the other ten species. The group in Platanthera is only confined to the area from the south fringe of the Xizang (Tibet) Plateau to the Hengduan Mountain Region. It seems that the genus has been affected by intense lift of the area, causing variation and differentiation and giving rise to the group due to the long-term natural selection. Mt. Emei in Sichuan Province is the eastern limit of distribution of the group, where there are three spcies, among which two (P. deflexilabella and P. longiglandula) are endemic to the mountains. In addition, among Risleya (1 species), Diphylax (3 species) and Diplomeris (2 species), three genera typical of distribution in the Sino-Himalayan Subregion, Risleya and Diphylax have Mt. Emei as their eastern limit. Eleven species, belonging to elements of the SinoJapanese Subregion, occur only from Japan to Western Sichuan with Mt. Emei as the western limit. Among nine species, belonging to elements of the Sino-Himalayan Subregion, six occur from the Himalayas to W. Sichuan and three of them are endemic to the Hengduan Mountain Region, with Mt. Emei as their eastern limit of distribution. There are eight endemic species and one variety of orchids in Mt. Emei, making up about 11.59% of the total endemic species in the Hengduan Mountain Region. Orchid floristic elements in Mt. Emei are obviously different from those in Mt. Jinfo, the former being mainly of the Sino-Himalayan Subregion, while the latter being mainly of the Sino-Japanese Subregion. From the distribution patterns of the orchid floristic elements in the Hengduan Mountain Region and Eastern China, the Emei Mountain is considered important for drawing a boundary line between the Sino-Japanese Subregion and the Sino-Himalayan Subregion. The discussion may be summarized as follows: the floristic features of the orchid flora in the Hengduan Mountain Region are: (1) rich in species, complex in geographical components, eminent vicarism and differentiation, and prolific in endemic species; (2) terrestrial life form is dominant one; (3) mainly consisting of temperate and subtropical East-Asian elements, es pecially, elements of Sino-Himalayan Subregion, though with some tropical elements and elem-ents of other regions.  相似文献   

13.
云南樟科植物区系地理   总被引:5,自引:2,他引:3  
李捷 《云南植物研究》1992,14(4):353-361
  相似文献   

14.
Herminium is a genus of about 26 species, mainly distributed in the temperate and subtropical regions of Asia and Europe. Yunnan, Sichuan and Xizang in China are the present distribution centre as well as differentiation centre of the genus. In the present paper, taxa of Herminium hitherto recorded in China are taxonomically and phytogeographically discussed and revised, and, as a result, 18 species are recongnized, including two newly recorded species, H. angustilabre King et Pantl. and H. quinquelobum King et Pantl., and 12 species endemic to China. A full list of synonyms is given, a key to the species is provided and the distribution areas of all taxa are mapped.  相似文献   

15.
A new system of classification of Magnoliaceae proposed. This paper deals mainly with taxonomy and phytogeography of the family Magnoliaceae on the basis of external morphology, wood anatomy and palynology. Different authors have had different ideas about the delimitation of genera of this family, their controversy being carried on through more than one hundred years (Table I). Since I have been engaged in the work of the Flora Reipublicae Popularis Sinicae, I have accumulated a considerable amount of information and material and have investigated the living plants at their natural localities, which enable me to find out the evolutionary tendencies and primitive morphological characters of various genera of the family. According to the evolutionary tendencies of the characters and the geographical distribution of this family I propose a new system by dividing it into two subfamilies, Magnolioideae and Liriodendroideae Law (1979), two tribes, Magnolieae and Michelieae Law, four subtribes, Manglietiinae Law, Magnoliinae, Elmerrilliinae Law and Micheliinae, and fifteen genera (Fig. 1 ), a system which is different from those by J. D. Dandy (1964-1974) and the other authors. The recent distribution and possible survival centre of Magnoliaceae. The members of Magnoliaceae are distributed chiefly in temperate and tropical zones of the Northern Hemisphere, ——Southeast Asia and southeast North America, but a few genera and species also occur in the Malay Archipelago and Brazil of the Southern Hemisphere. Forty species of 4 genera occur in America, among which one genus (Dugendiodendron) is endemic to the continent, while about 200 species of 14 genera occur in Southeast Asia, of which 12 genera are endemic. In China there are about 110 species of 11 genera which mostly occur in Guangxi, Guangdong and Yunnan; 58 species and more than 9 genera occur in the mountainous districts of Yunnan. Moreover, one genus (Manglietiastrum Law, 1979) and 19 species are endemic to this region. The family in discussion is much limited to or interruptedly distributed in the mountainous regions of Guangxi, Guangdong and Yunnan. The regions are found to have a great abundance of species, and the members of the relatively primitive taxa are also much more there than in the other regions of the world. The major genera, Manglietia, Magnolia and Michelia, possess 160 out of a total of 240 species in the whole family. Talauma has 40 species, while the other eleven genera each contain only 2 to 7 species, even with one monotypic genus. These three major genera are sufficient for indicating the evolutionary tendency and geographical distribution of Magnoliaceae. It is worthwhile discussing their morphological characters and distributional patterns as follows: The members of Manglietia are all evergreen trees, with flowers terminal, anthers dehiscing introrsely, filaments very short and flat, ovules 4 or more per carpel. This is considered as the most primitive genus in subtribe Manglietiinae. Eighteen out of a total of 35 species of the genus are distributed in the western, southwest to southeast Yunnan. Very primitive species, such as Manglietia hookeri, M. insignis and M. megaphylla, M. grandis, also occur in this region. They are distributed from Yunnan eastwards to Zhejiang and Fujian through central China, south China, with only one species (Manglietia microtricha) of the genus westwards to Xizang. There are several species distributing southwards from northeast India to the Malay Archipelago (Fig. 7). The members of Magnolia are evergreen and deciduous trees or shrubs, with flowers terminal, anthers dehiscing introrsely or laterally, ovules 2 per carpel, stipule adnate to the petiole. The genus Magnolia is the most primitive in the subtribe Magnoliinae and is the largest genus of the family Magnoliaceae. Its deciduous species are distributed from Yunnan north-eastwards to Korea and Japan (Kurile N. 46’) through Central China, North China and westwards to Burma, the eastern Himalayas and northeast India. The evergreen species are distributed from northeast Yunnan (China) to the Malay Archipelago. In China there are 23 species, of which 15 seem to be very primitive, e.g. Magnolia henryi, M. delavayi, M. officinalis and M. rostrata, which occur in Guangxi, Guangdong and Yunnan. The members of Michelia are evergreen trees or shrubs, with flowers axillary, anthers dehiscing laterally or sublaterally, gynoecium stipitate, carpels numerous or few. Michelia is considered to be the most primitive in the subtribe Micheliinae, and is to the second largest genus of the family. About 23 out of a total of 50 species of this genus are very primitive, e.g. Michelia sphaerantha, M. lacei, M. champaca, and M. flavidiflora, which occur in Guangdong, Guangxi and Yunnan (the distributional center of the family under discussion) and extend eastwards to Taiwan of China, southern Japan through central China, southwards to the Malay Archipelago through Indo-China. westwards to Xizang of China, and south-westwards to India and Sri Lanka (Fig. 7). The members of Magnoliaceae are concentrated in Guangxi, Guangdong and Yunnan and radiate from there. The farther away from the centre, the less members we are able to find, but the more advanced they are in morphology. In this old geographical centre there are more primitive species, more endemics and more monotypic genera. Thus it is reasonable to assume that the region of Guangxi, Guangdong and Yunnan, China, is not only the centre of recent distribution, but also the chief survival centreof Magnoliaceae in the world.  相似文献   

16.
广东裸子植物区系的特点   总被引:5,自引:1,他引:4  
周云龙  廖文波   《广西植物》1995,15(4):319-322+223+324
广东省裸子植物共有8科18属34种,分别占中国同类的80.0%,52.9%和17.6%。其中泛热带分布2属,热带亚洲至热带大洋洲1属,热带亚洲1属,北温带5属,东亚和北美间断分布1属,东亚分布3属,中国特有分布5属,即热带成分共仅4属占22.2%,而亚热带至温带成分14属占77.8%为绝对优势。分析表明:广东裸子植物区系体现了东亚裸子植物区系的特点,其原始中心和现代分布中心都在中国亚热带。同时论文还将广东裸子植物种的分布区类型划分为20个亚型。  相似文献   

17.
横断山区唇形科植物的地理分布   总被引:8,自引:0,他引:8  
李锡文 《植物研究》1989,9(2):103-122
横断山区唇形科植物相当丰富,有46属240种,在国内仅次于云南和四川,但明显多于其它省区。通过对其属、种的分布区类型分析,其地理分布表现如下一些特征;1)从属的分布区类型来说,横断山区唇形科植物主要是温带性质,温带分布区类型的属数占总属数(世界分布的不计算在内,下同)85.3%,其中东亚分布类型为数最多,占总属数34.1%,其次是旧世界分布类型和北温带分布类型,分别占总属数29.2%和12.2%,而东亚分布类型中占绝对优势的是中国喜马拉雅分布亚型。2)从种的分布类型来说,我国特有分布的种占绝大多数,占总种数75%,而温带分布类型和热带分布类型分别占总种数20%和5%。在我国特有分布的种中横断山区特有的占72.8%。在横断山区特有分布的种中滇西北一地特有的占横断山区特有总种数32.1%,川西南一地特有的占横断山区特有总种数9.9%,滇西北和川西南两地共同特有的占横断山区特有总种数25.2%,要是把滇西北川西南看成一整体无疑是横断山区特有种分布中心,占横断山区特有总种数67.2%。3)滇西北川西南特有种分布中心,从其特有种组成分析,其成因有历史的也有生态的,但生态成因多于历史成因,因此该中心的植物区系较为年青,这是由于新构造运动强烈、垂直气候带变化明显,冰川多次进退,导致气候上下位移频繁以横断山脉的纵向深切,促进植物在发展过程中强烈分化的结果。  相似文献   

18.
簇毛黄耆亚属的种类主要沿亚洲的“山链”分布,即横断山,喜马拉雅,查谟和克什米尔,帕米尔—阿赖,兴都库什和苏莱曼山脉,表达了东亚、西亚和中亚的植物区系地理关系。本文基于亚属的分布式样,对其8个分布区进行了分析生物地理学中的成分分析。结果表明,这8个分布区可划分为4类,即1)华北—东北;2)横断山和西藏;3)西喜马拉雅,西巴基斯坦,塔吉克斯坦;4)内蒙古—新疆。在本亚属的分布式样中,有两个地理“结点”,即横断山和西喜马拉雅,后者主要指克什米尔。推断地理上的衍进方向是由东向西发展,喜马拉雅是连接东西分布的通道。  相似文献   

19.
青藏高原蝇科昆虫生物地理初探   总被引:3,自引:0,他引:3  
对青藏高原蝇科昆虫进行了生物地理学研究.青藏高原已知蝇科9亚科42属574种,以特有类群占优势.其中特有属占11.9%,特有种占66.2%,文中讨论了该地区区系成分的多源性,特有成份的特异性及青藏高原北缘特有属的起源与演化,特有种的狭域分布现象及理论探讨.讨论了该地区与其它地区间隔分布的多样性及高原蝇科昆虫的适应性.分析了青藏高原的隆起与冰期对蝇科昆虫的作用.青藏高原的横空崛起以及第四纪冰期--间冰期的循环往复,导致该地区生境千差万别,使蝇科区系不仅有地域分异,且垂直差异显著.在此期间,北方物种向南入侵,南北成分交互渗透,高山类群适应进化,使许多特有成分在这里被陶冶、孕育,故而造成了该地区蝇科区系的特有性和物种的多样性.  相似文献   

20.
Dirk Brandis 《Hydrobiologia》2001,452(1-3):89-100
The Himalayas are known to be a geologically young and dynamic mountain range hosting an endemic flora and fauna. To date, for freshwater crabs, one endemic subgenus within the genus Potamon, Potamon (Himalayapotamon) Pretzmann, 1966, has been described from the Himalayas. This subgenus includes two species, Potamon atkinsonianum (Wood-Mason, 1871) and Potamon emphysetum (Alcock, 1909). The taxonomic position of these two species is reconsidered. The subgenus Himalayapotamon is raised to generic level and its systematic and zoogeographic position is discussed. Based mainly on the morphology of the male copulatory system, Himalayapotamon belongs to the family Potamidae. It is more related to the Eurasian genus Potamon Savigny, and is distinct from the South-East Asian genus Potamiscus as well as from the Indian freshwater crabs of the family Gecarcinucidae. Zoogeographically Himalayapotamon appears to be an endemic genus related to Potamon, both genera presumably being isolated during the Miocene when the Gangetic waters were separated from the western Eurasian river systems. Further speciation occurred during glacial periods.  相似文献   

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