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1.
为探讨山地植物区系构成特征及其垂直梯度的生态意义,根据对三峡大老岭地区植被垂直样带 调查获得的植物区系资料,分析了该地区植物区系成分构成的基本特征及其随海拔梯度的变化趋势,寻找了区系平衡点的位置;并利用聚类方法分析了山地气候垂直分异对区系成分构成的影响。结果表明:①大老岭植物区系具有温带性质,但仍反映了与热带区系的历史联系,有强烈的区域性;②属的分布区类型可归为热带分布、温带分布、地中海—中亚中心和东亚中心4组,各组区系成分的垂直梯度特征不同;热带、亚热带成分与温带成分的平衡点大致位于海拔650m;③区系成分构成和属的物种数量构成的聚类分析结果一致显示了植物区系构成与山地气候和植被垂直带相对应的格局。  相似文献   

2.
 台湾位于欧亚大陆东南缘的海洋中,地处热带的北部和亚热带的南部,约为21°45′~15°56′N,119°18′~124°34′E,是中国最大的岛屿。它是受季风气候强烈影响的地区之一,热量丰富,雨量充沛,干湿季明显。具有一个非常丰富的岛屿和山区植物区系。就其种子植物而言,约有186科,1201属,3656 种,包括热带属742属,温带属346属。根据台湾植物区系中各大科、主要植物群落优势种和中国特有种的地理分布以及热带属在整个植物区系中的主导地位,台湾地区的植物区系主体具有明显的亚热带性质。中国台湾本地特有种十分丰富,其比例远高于中国特有种的比例。这似乎表明台湾植物区系是一个古老区系在多次地质事件侵袭后又起活化的历史演变的结果。新老成分并存、共同发展是台湾植物区系的重要特点。通过台湾全部属和非特有种在周边地区地理分布的分析,中国台湾植物区系与中国大陆的关系最为密切,是东亚植物区系的重要组成部分,因此在植物分区上应属于泛北极植物区的东亚植物区系。  相似文献   

3.
毛竹生产潜力很大且具有较高的经济价值,主要分布在四川长宁、江安、兴文等县。在统计毛竹林下维管植物种类数目的基础上,对该区维管植物区系进行了初步分析。研究结果表明:长宁毛竹林下维管植物共115种,分属54科98属,科属地理成分分析结果表明:这54科可划分为7个分布型和5个变型,其中以泛热带分布为主;98属可划分为13个分布型和4个变型,其中以泛热带分布、东亚和北美洲间断分布为主。因此,其区系地理成分复杂,以热带成分为主,但同时受到温带区系成分的影响,特有植物贫乏。  相似文献   

4.
 秦岭是中国长江和黄河两大水系的分水岭,位于北纬32°5′至34°45′;东经104°30′至115°52′,最高峰达3767m。该山区是我国温带植物区系最丰实的地区之一,约有种子植物3124种,隶属于158科,892属。包括热带属220属,温带属563属,和中国特有属39属。根据该山区植物区系中各大科、主要植物群落优势种和组成种类的温带性质以及温带属在整个植物区系中的主导地位。该山区的植物区系和植被具有明显的温带性特点。特有种和非特有种的分析结果表明,该山区植物区系的特点还表现在高度特有性和以中国-日本森林植物区系为主体方面。    根据古植物学资料分析,秦岭地区植物区系的起源时间不会晚于晚白垩纪;植物群落的主要成份可能以原地生长的种类为主;秦岭及其邻近古老山区,不仅对自身的植物区系和植被具有较大的发生意义,而且对东亚植物区系具有始生性质。  相似文献   

5.
本文对内蒙古赫尔洪德沙地樟子松自然保护区维管植物的组成特征、区系地理成分进行了分析。结果表明:该区植物种数较丰富,有维管植物65科226属448种,被子植物占优势,共444种。科的组成分析表明,优势科现象十分显著。种的地理成分分析表明,温带成分的种占优势,热带成分的种所占比例很小,主要以温带亚洲成分、北温带成分和旧大陆温带成分为主,表明温带属性是该地区植物区系的基本属性。区系地理成分复杂多样、联系广泛。  相似文献   

6.
通过半个世纪以来对金佛山近2000号藓类植物标本的鉴定,现确定金佛山藓类植物有40科,133   属和245种(包括4亚种、9变种和1变型)。其区系成分以东亚成分为主(33.77%),其次为温带成分   (28.57%)及热带、亚热带成分(24.68%)。文内还全面分析了金佛山藓类植物区系及我国南北8个山区藓   类植物区系之间的关系,用排序方法统计它们之间的相似性与非相似性系数,并着重就金佛山藓类植物区  系的过渡性特点作了探讨,提出在该山区与其邻近地区,存在一个苔藓植物东亚特有属的分布中心。  相似文献   

7.
中国种子植物特有属是局限分布于中国行政区域范围内的植物成分,就其分布特点看,集中分布于中国南部亚热带广阔区域。由于中国地域广袤,虽然大多数特有属分布在东亚自然地域范围内,但南部特有属的分布范围已进入古热带植物区的马来亚森林植物亚区的北部,而西部的特有属的分布范围已进入青藏高原地区。局限于不同地域分布的特有属,各自的起源发生、所经历的地质历史过程存在一定差别。本文以自然地理区划作为研究中国种子植物特有属分布区类型的依据,将中国特有属分布区类型划分为中国东部和中部特有分布变型、中国南部特有分布变型、中国西部特有分布变型和中国北部特有分布变型4类。其中中国南部特有分布变型所含特有属为热带区系成分,其它3个特有分布变型所含特有属为温带区系成分。这样能较客观地反映中国特有属的自然地理特征,有利于研究局部地区植物区系的地质历史演变过程。  相似文献   

8.
对陈巴尔虎草甸草原自然保护区维管植物的组成特征、区系地理成分进行了分析,结果表明:该区植物种数较丰富,有维管植物61科240属466种,被子植物占优势。科的组成分析表明,优势科现象十分显著。种的地理成分分析表明,温带成分的种占优势,热带成分的属种所占比例很小,温带属性是该地区植物区系的基本属性。  相似文献   

9.
本文根据对舟山群岛种子植物348个种(及种以下分类单位)在18个地理单位的分布状况进行 计算机聚类分析和主成分分析(PCA),表明了该群岛与我国大陆的浙江和江苏植物区系有着密切的亲 缘关系和相似性;与日本和我国台湾植物区系的联系则不如一般所认为的那样接近,当然,仍有不少十 分有意义的连锁植物存在于三者之间。     舟山群岛在植物区系区划上应为中亚热带北部亚地带,区系特点之一是岛屿植物较发达,而山地森 林区系则与我国南方植物区系相接近。  相似文献   

10.
湘西北壶瓶山自然保护区植物区系   总被引:1,自引:0,他引:1  
壶瓶山自然保护区具有丰富的植物区系成分,现知维管束植物有205科(蕨类和拟蕨类 植物40科,裸子植物7科,被子植物158科),839属,约1961种(包括154变种)。其中,古  和原始的科、属不乏其代表。从种子植物属的分布区类型的比较分析,该区具有我国15个种子植物属的分布区类型中的14个,表明了与世界各地区植物区系的联系程度。另一方面,该 地区的植物区系虽含有丰富的热带成分,但根据各类温带属占该区总属数的百分比以及分布于该地区的中国特有属中的木本属几乎所有都是落叶的乔木或灌木,该区的植物区系性质明显偏重于温带性质。而且,这种温带性质可能与该区的山体海拔高度有着重要的联系。  相似文献   

11.
 Xizang (Tibet) is rich in Leguminosae flora, comprising 41 genera and 254 species so far known, exclusive of the commonly cultivated taxa (including 11 genera and 16 species). There are 4 endemic genera (with 8 species), 10 temperate genera (with 175 species) and 19 tropical genera (with 46 species) as well as the representatives of those genera whose distribution centers are in East Asia-North  America, Mediterranean and Central Asia.       1.  There are altogether 4 endemic genera of Leguminosae in this region. Accord- ing to their morphological characters, systematic position and geographical distribution, it would appear that Salweenia and Piptanthus are Tertiary paleo-endemics, while Straceya and Cochlianths are neo-endemics. Salweenia and Piptanthus may be some of more primitive members in the subfamily Papilionasae and their allies are largely distributed in the southern Hemisphere.  The other two genera might have been derived from the northern temperate genus Hedysarum and the East Asian-North American genus Apios respectively, because of their morphological resemblance. They probably came into existanc during the uplifting of the Himalayas.       2. An analysis of temperate genera       There are twelve temperate genera of Leguminosae in the region, of which the more important elements in composition of flora, is Astragalus, Oxytropis and Cara- gana.       Astragalus  is a  cosmopolitan  genus comprising 2000 species, with its center distribution in Central Asia. 250 species, are from China so far known, in alpine zone of Southwest and Northwest, with 70 species extending farther to the Himalayas and Xizang Plateau.       Among them, there are 7 species (10%) common to Central Asia, 12 species (15.7%) to Southwest China and 40 species (60%) are endemic, it indicates that the differentia- tion of the species of the genus in the region is very active, especially in the subgenus Pogonophace with beards in stigma. 27 species amounting to 78.5% of the total species of the subgenus, are distributed in this region.  The species in the region mainly occur in alpine zone between altitude of 3500—300 m. above sea-level. They have developed into a member of representative of arid and cold alpine regions.      The endemic species of Astragalus in Xizang might be formed by specialization of the alien and native elements. It will be proved by a series of horizontal and vertical vicarism of endemic species.  For example, Astragalus bomiensis and A. englerianus are horizontal and vertical vicarism species, the former being distributed in southeast part of Xizang and the latter in Yunnan; also A. arnoldii and A. chomutovii, the former being an endemic on Xizang Plateau and latter in Central Asia.      The genus Oxytropis comprises 300 species which are mainly distributed in the north temperate zone. About 100 species are from China so far known, with 40 species extending to Himalayas and Xizang Plateau.  The distribution, formation and differ- entiation of the genus in this region are resembled to Astragalus.  These two genera are usually growing together, composing the main accompanying elements of alpine mea- dow and steppe.      Caragana is an endemic genus in Eurasian temperate zone and one of constructive elements of alpine bush-wood. About 100 species are from China, with 16 species in Xi- zang. According to the elements of composition, 4 species are common to Inner Mon- golia and Kausu, 4 species to Southwest of China, the others are endemic. This not only indicates that the species of Caragana in Xizang is closely related to those species of above mentioned regions, but the differentiation of the genus in the region is obviously effected by the uplifting of Himalayas, thus leading to the formations of endemic species reaching up to 50%.      3. An Analysis of Tropical Genera      There are 19 tropical genera in the region. They concentrate in southeast of Xizang and southern flank of the Himalayas. All of them but Indigofera and Desmodium are represented by a few species, especially the endemic species. Thus, it can be seen that they are less differentiated than the temperate genera.      However, the genus Desmodium which extends from tropical southeast and northeast Asia to Mexio is more active in differentiation than the other genera. According to Oha- Shi,s system about the genus in 1973, the species of Desmodium distributed in Sino-Hima- laya region mostly belong to the subgenus Dollinera and subgenus Podocarpium.  The subgenus Dollinera concentrates in both Sino-Himalaya region and Indo-China with 14 species, of which 7 species are endemic in Sino-Himalaya.  They are closely related to species of Indo-China, southern Yunnan and Assam and shows tha tthey have close con- nections in origin and that the former might be derived from the latter.      Another subgenus extending from subtropical to temperate zone is Podocarpium. Five out of the total eight species belonging to the subgenus are distributed in Sino- Himalaya and three of them are endemic.      An investigation on interspecific evolutionary relationship and geographic distribu- tion of the subgenus shows that the primary center of differentiation of Podocarpium is in the Sino-Himalaya region.      Finally, our survey shows that owing to the uplifting of the Himalayas which has brought about complicated geographic and climatic situations, the favorable conditions have been provided not only for the formation of the species but also for the genus in cer-tain degree.  相似文献   

12.
 Situated in western part of Sichuan Province, 29°30'N, 103°20'E, the sacred Mt. Emei is one of the well-known large mountains in China. Its summit is about 3100 m ab- ove sea level with a relative height of 2550 m.        The orchid flora in Mt. Emei so far known comprises 47 genera and 109 species, among which 21 are epiphytes, 83 terrestrials and 5 saprophytes (Table 1.)        1.  The vertical distribution of the orchid flora in the mountain. The epiphytic orchids are concentrated in the lower region  below Hongchunping and Wanniansi (1100 m alt.), where there are 20 species, which make over 95% of epiphytic species; the upper limit for the epiphytic orchids is Jiulaodong and Chudian ( 1800 m alt.). The terrestrial orchids also mainly occur at the lower region below Jiulaodong and Chudian (1800 m alt.), where there are 54 species, most of which are found at even lower part of the mountain, below Hongchunping and Wanniansi (1100 m alt.). The tropicas orchids in the mountain, such as Cleisostoma, Vanda, Holcoglossum, Tropiclia, Thunia, Mischobulbum, Ludisia, Anoectochilus, Odontochilus, etc. all grow only at the lower part of the mountain below Hongchunping and Wanniansi (1100 m alt.).        2. The floristic features of the orchid flora in the Mt. Emei.        (1)  The orchid flora in the mountain so far known comprises 47 genera (over 2/3 of the total orchid genera in Sichuan) and 109 species (over 1/3 of the total orchid species in Sichuan). The Mt. Emei is very rich in orchid species, as compared with neighbouring mountains of same magnitude, such as Mt. Shennonjia in western Hubei, Qin Ling in sou- thern Shaanxi, Jinfo Shan in south-eastern Sichuan, and Erlang Shan in western Sichuan.        (2)  The orchids in the mountain are complex in floristic components as indicated below:        1)  Twenty seven species, belonging to 18 genera, are widespread, covering the whole East-Asian region.        2)  Twenty three species, belonging to 15 genera, are the elements of the Sino-Japanese Subregion. Among them 13 species occur only in Japan and eastern China with the mountain ar the westernmost limit, but the other species extend westwards as far as Kangding and ErLang Shan or Baoxing in Sichuan Province.        3)  Forty two species, belonging to 22 genera, are the elements of the Sino-Himala-yan Subregion, with 5 species having their range extending from the Himalayan  region eastwards to Mt. Emei.        4)  Some tropical genera (8 species), belonging to Indo-Malaysian floristic elements, have the mountain as their northern limit of distribution.       The orchid flora of the Mt. Emei contains not only the East-Asian elements, but also some Indo-Malaysian elements, though its composition is mainly of the temperate and subtropical Eastern Asian (Sino-Japanese) ones.        (3)  The orchid flora in the mountain is characterized by geographical vicariation and differentiation.       There are nine species-pairs (belong to genera Calanthe,  Platanthera,  Dendrobium etc.) of the vertical vicarism and six species-pairs (belonging to genera Tropidia, Aneoctochilus, Mischobulbum, Gymnadenia Orchis, etc.) of the horizontal vicarism in the Mt.  Emei.       Remarkable differentiation of orchid flora in the Mt. Emei is shown in the abundance of endemic elements and as clear geographical vicariation.        (4)  There are 8 endemic species and one variety of orchids in the Mt. Emei, more  abundant than in Xizang.      The floristic features of the orchid flora of the Mt. Emei are rich in species, compara tively complex in components, rather prolific in endemic species, and characterized by geographical vicariation and differentiation. The orchid flora in the Mt. Emei mainly consists of the subtropical and temperate East-Asian elements, with a  considerable proportion of tropical elements though.  相似文献   

13.
鄂西神农架地区的植被和植物区系   总被引:1,自引:0,他引:1  
 Shennungia is generally known as “The highest mountain in Central China”. It is situated at latitude 31°342'N., longitude 110°35'E. in western Hupeh.       The area explored is deeply cut in all sides by five V-shaped valleys, giving the landscape a steep topography.  Its summit is about 3105 meters above the sea level, and the relative altitude is from 1000-2000 meters.      The climate of the region is warm temperate.  The differences of humidity-warmth condition between the eastern and the western flanks are quite marked.      In western Hupeh and the adjacent area of Szechuan the rugged topography still preserves some tracts of natural forests at higher elevations.  Our vegetational survey is confined to localities above 1500 meters. The collection of plant samples of the flora is extended to the whole mountain from the foothill to the peak.  The present article deals with only a part of the results of our survey.      1.  The vertical vegetation belts of Mt. Shennungia and relationships with other regions:  The vegetation belts on the eastern and the western flanks of the mountain are shown in diagram 2 and 3.  The comparison of the vertical vegetation zones of the Mt. Shennungia with those of the Yülungshan in N. W. Yunnan and the eastern Himalaya to the west and with those of Hwangshan and Central Japan to the east is shown in table 4, It shows that the plant communities of the Mt. Shennungia are of temperate nature, and they are more closely related to those of Hwangshan in S. Anhwei and of Central Japan than to the eastern Himalaya.      2.  Floristic composition: The generic ranges of flowering plant are relatively distinct and stable. Various distributional patterns of genera are analysized.      1)  Statistics of the genera in various distributional patterns: The total number of genera of flowering plants in this region are 762, belonging to the following four categories. A) tropical genera 239 (31.3%), B)  temperate  genera  416 (54.7%),  C) endemic genera 47 (6%), and D) comsmopolitan genera 61 (8%).       2)  Endemic genera:  An examination of the composition of the flora in western Hupeh reveals that 47 endemic Chinese genera occur in this mountain of which 24 are monotypic genera, 20 oligotypic and 2 multitypic as shown in Table 4. The arborescent genera are nearly all deciduous. They are of temperate nature.       3)  Temperate genera:  There are 416  genera in  wastern Hupeh.  They  are subdivides into the following three groups according to their distributional patterns: A)  The north temperate genera: There are 159 genera belonging to 62 families in western Hupeh. B)  Eastern Asian genera:  There are 117 genera belonging to 69 families in western Hupeh.  Among them 22 are common to the western Szechuan, adjacent regions of Yunnan and the Eastern Himalaya.  The remaining 95 genera are commom to both eastern China and Japan. C) The Eastern Asian-eastern North- American genera:  Of the total 762 genera known in western Hupeh, 64 are disjunc- tively distributed in both eastern Asia and eastern North-America.       4)  The tropical genera: Of the 762 genera of the flowering plant of western Hupeh, 239 (31%) are of tropical nature.       Finally, our survey shows:  1. Many of the primitive temperate genera and ende- mic relicts concentrate in western Hupeh and the adjacent region of Szechuan indica- ting that it might be one of refuges of tertiary flora. Moreover, it might also be one of the most important regions of differentiation, development and distribution of tem- perature flora. 2.  The vegetation of this region is not only of temperate nature, but also of a transitional nature. 3.  According to an analysis of the flora and a compari- son of the vertical distribution of the vegetation of Yülungshan and Eastern Himalaya to the west with Hwangshan and Central Japan to the east, the floristic affinity of western Hupeh is more closely related to eastern China and Central Japan rather than to the Eastern Himalaya, and phytogeographically this region is intermediate between the Sino-Himalayan and the Sino-Japanese patterns.  However, the problem of phyto- geography of western Hupeh and the adjacent region of Szechuan is a complicated one requiring further study.    相似文献   

14.
The Gongga Mountain Region, located on the eastern fringe of Qinghai- Xizang Plateau and at the north-eastern end of Hengduan Mountains, is one of the well-known large mountain areas in Sichuan Province.  There are forty five high peaks with the elavation of 6000 m or over in the area, among which the Gongga Mountain is the highest one, with its summit being at the altitude of 7556 m, whereas the Dadu River Valley in the eastern part of the area is only 1150 m above sea level;  The rela- tive height in the region is thus about 6400 m.      As we know so far the orchids in Gongga Mountain Region comprise 34 genera and 75 species with 1 variety, of which 12 species are epiphytes, 59 species with 1 variety terrestrials and 4 species saprophytes (Table 1.).      I.  The geographical distribution in the Gongga Mountain Region.      The vertical distribution of the orchids in the area.      Eastern flank:  There are 39 species with  I  variety  of orchids  at  1150-2300 (-2400) m alt. in the subtropical evergreen broadleaf forest zone, of which 12 species, such as Bulbophyllum andersonii, Dendrobium hancockii, Otochilus porrecta, etc., are epiphytic (including a semiepiphyte, Pleione bulbocodioides), 25 species with 1 variety, such as Bletilla formosana, Calanthe davidii, Cypripedium henryi, etc., are terrestrial, and 2 species are saprophytic (i.e. Gastrodia elata and Neottia listeroides), the upper limit of the real epiphytic orchids is 1800 m alt.  At the altitude 2300(-2400)-3600 (-3800) m, in the coniferous forest zone, found are 23 species, including 20 terrestrial species with 1 variety, such as Amitostigma gonggashanicum, Calanthe fimbriata, Coe- loglossum viride, etc., 2 saprophytic species (Neottia acuminata and Risleya atropurpu- rea) and one semiepiphytic species.  There are only 2 terrestrial species (i.e. Cypripe- dium tibeticum and Orchis chusua) at 3600(-3800)-4000m alt., in alpine shrub zone, the upper limit of the terrestrial orchids being 4000 m alt.  At 4000-4400 m alt., in alpine meadow zone no orchids have so far been found.      Western flank:  There are 14 species of orchids, such as Habenaria limprichtii, Hemipilia flabellata, Satyrium ciliatum, etc., at 2300-2800 m alt., in the river valley shrub zone, and they all belong to the terrestrial orchids.  At the altitude of 2800- 3800m, in the coniferous forest zone found are 19 species of orchids, among which 18 species are terrestrial (such as Amitostigma monanthum, Cephalanthera longifolia, Pe- ristylus coeloceras, etc.) and one is saprophytic.  There are only 4 species of terrestrial orchids (i.e. Cypripedium tibeticum, Gymnadenia orchidis, Orchis chusua and O. dian- tha) at 3800-4800 m alt., in the alpine shrub-meadow zone, the upper limit of vertical distribution of terrestrial orchids being 4400 m alt.  Twelve species here are common to the eastern flank.       II.  The floristic composition of orchids in Gongga Mountain Region.       1.  Twenty three species, belonging to 13 genera, are widespread in Whole East- Asian Region.       2.  Eight species, belonging to 8 genera, are the elements of the Sino-Japanese Subregion.      3.  Forty one species with 1 variety, belonging to 24 genera, are the elements of the Sino-Himalayan Subregion, more than five times the elements of the Sino-Japanese Subregion.      4.  The floristic features of the orchids in the area.       (1)  The floristic elements are mainly temperate and subtropical ones.       (2)  The life form is mostly terrestrial.       (3)  The species endemic to China are prolific (35 species with 1 variety, belong- ing to 18 genera, are endemic to China, and 26 species with 1 variety are distributed in south-western China and its adjacent region; Amitostigma gonggashanicum is endemic to the area).      The floristic composition of orchids in the area is characterized by the dominance of terrestrial species and temperate and subtropical East-Asian elements, though with a few Indo-African tropical elements (such as genus Satyrium (1 species) ).      In conclusion, it may be considered that the species of orchids are abundant and floristic elements are comparatively complex in the Gongga Mountain Region.  相似文献   

15.
兰科在横断山地区是维管束植物中的大科之一,共有91属,363种及9变种。 4属为我国特有属,其中1属为本地区所特有;155种及9变种为我国特有种。  其中69种及5变种为本地区所 特有。本文对属、种进行了分析,并对全部种的分布格局作了详细的介绍,概述了本地区兰科植物的区系组成及特点。本文从兰科植物属、种的分布提出了四川峨眉山是东亚植物区中划分中国-喜马拉雅植物亚区和中国-日本植物亚区的分界线上的一个重要的点的看法。  相似文献   

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