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1.
This paper is a preliminary study on the Sabiaceae in aspects of its morphology,
taxonomy and geography. We propose that the Sabioideae and Meliosmoideae as two
new subfamilies of Sabiaceae according to the external morphology, flower structure
and geographical distribution of these two genera respectively.
This paper follows the taxonomic concepts of Luetha Chen on Sabia and C. F.
van Beusekom on Meliosma. We agree with them for their classification of these two
genera above the specific rank. As to the revision work of Sabia by van de Water
and C. F. van Beusekom’s work on Meliosma we disagree for their unduly broad
specific concepts. We rather treat the species of these two genera according to their
habitats in regions on a relatively narrower sense. The genus Sabia of China are
classified into 2 tribes, with 16 species, 5 subspecies and 2 varieties in which 4 sub-
species and l variety are as new combinations, the genus of Meliosma in China are
classified into 2 subgenera with 29 species, and 7 varieties of which 4 varieties are new
combinations.
After examining the affinity of the species of Sabia and Meliosma in China and
its neighboring nations such as Burma, Japan and Bhutan, we found that their migra-
tion initiated from China, as the primitive species of these two genera occured in
northeast and central part of Yunnan, sou theast of Sichuan, north of Guizhou and
west of Hubei, the region may probably be the main origin of these two genera.
As shown in tables 1 & 2, the localities where the species of these two genera den-
sely populate they are from Yunnan, Guangxi, and Guangdong coinciding with the
concepts of C. F. van Beusekom and van de Water about the distribution of exotic
species of these two genera, it may reasonable be pointed out that the center of distri-
bution of these two genera is Yunnan, Guangxi, Guangdong and nieghboring nations,
upper Burma and northern Vietnam. Futhermore, it may be seen that starting from
this center the number of species become less and less as they proceed far and far awaybut become more advance in evolution. 相似文献
2.
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
3.
中国-喜玛拉雅特有属——蓝钟花属的分类修订 总被引:2,自引:0,他引:2
Krishna K. Shrestha 《中国科学院研究生院学报》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 karyomorphology recommends a new infrageneric classification of the genus, recognizing 23 species, belonging to two subgenera, four sections and four subsections. One subgenus(Subgen. Micranthus), one section(Sect. Suffruticulosi) and two subsections(Subsect. Flavi and Subsect. 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 Nepal and one to NW India). It is evident that Cyananthus is one of the most primitive genera of Campanulaceae and within the genus, subgenus Cyananthus(Sect. Stenolobi) is more primitive than the subgenus Micranthus. It is also suggested that SW China(most probably Yunnan) is the center of origin of Cyananthus, considering the occurrence of as many as 20 species of Cyananthus, representing several primitive taxa and many endemic species. 相似文献
4.
1) The Compositae in Tibet so far known comprise 508 species and 88 genera,
which nearly amounts to one fourth of the total number of genera and one third of the
total number of species of Compositae in all China, if the number of 2290 species and 220
genera have respectively been counted in all China. In Tibet there are all tribes of Com-
positae known in China, and surprisingly, the large tribes in Tibetan Compositae are
also large ones in all China and the small tribes in Tibet are also small ones in all China.
Generally speaking, the large genera in Tibet are also large ones in all China and the
small genera in Tibet are likewise small ones in all China. In this sense it is reasonable to
say that the Compositae flora of Tibet is an epitome of the Compositae flora of all China.
In the Compositae flora of Tibet, there are only 5 large genera each containing 30
species or more. They are Aster, Artemisia, Senecio, Saussurea and Cremanthodium. And
5 genera each containing 10—29 species. They are Erigeron, Anaphalis, Leontopodium,
Ajania, Ligularia and Taraxacum. In addition, there are 77 small genera, namely 87%
of the total of Compositae genera in Tibet, each comprising 1—9 species, such as Aja-niopsis, Cavea and Vernonia, etc.
2) The constituents of Compositae flora in Tibet is very closely related to those of
Sichuan-Yunnan provinces with 59 genera and 250 species in common. Such a situation
is evidently brought about by the geographycal proximity in which the Hengtuang Shan
Range links southeastern and eastern Tibet with northern and northwestern Sichuan-
Ynnnan. With India the Tibetan Compositae have 59 genera and 132 species in common,
also showing close floristic relationships between the two regions. Apparently the floris-
tic exchange of Compositae between Tibet and India is realized by way of the mountain
range of the Himalayas. The mountain range of the Himalayas, including the parallel
ranges, plays a important role as a bridge hereby some members of the Compositae of
western or northern Central Asia and of the northern Africa or of western Asia have
migrated eastwards or southeastwards as far as the southern part of Fibet and northern
part of India, or hereby some Compositae plants of eastern and southeastern Asia or
Asia Media have migrated northwestwards as the northern part of Central Asia.
Some of the species and genera in common to both Tibet and Sinjiang indicate that
this weak floristical relationship between these regions is principally realized through two
migration routes: one migration route is by way of the Himalayas including the parallel
ranges to Pamir Plataeu and Tien Shan, or vice versa. The other migration route is by
way of northern Sinjiang to Mongolia, eastern Inner Mongolia, southwards to Gansu,
Qinghai (or western Sichuan), eastern Tibet up to the Himalayas, or vice versa.
However, Tibet is not entirely situated at a migration crossroad of the floral ele-
ments. An ample amount of the data shows that Compositae flora have a particular
capability of development in Tibet. of the total number of species of Tibetan Com-
positae, 102 species and 1 genus (Ajaniopsis Shih) are endemic. Besides, 8 genera are re-
gional endemics with their range extending to its neighbourhood. The higher percentage
of endemics at specific level than at generic in Tibetan Compositae may be a result of
active speciation in response to the new enviromental conditions created by the uplifting
of the Himalayas. The flora in Tibetan Plateau as a whole appears to be of a younger
age.
3) The uprising of the Himalayas and of the Tibetan Plateau accompanied by the
ultraviolet ray radiation, the microthermal climate and the high wind pressure has, no
doubt, played a profound influence upon the speciation of the native elements of Tibetan
Compositae. The recent speciation is the main trend in the development of the Com-positae flora native in Tibet in the wake of upheaval of the plateau. 相似文献
5.
中国种子植物特有属的数量分析 总被引:3,自引:0,他引:3
王荷生 《中国科学院研究生院学报》1985,23(4):241-258
Chinese flora with many endemic elements is highly important in the world’s
flora. According to recent statistics there are about 196 genera of spermatophytes, be-
ing 6.5% of total Chinese genera. These endemic genera comprising 377 species belong
to 68 families, among which the Gesneriaceae (28 genera), Umbelliferae (13), Compo-
sitae (13), Orchidaceae (12) and Labiatae (10) are predominant. The tropical type
containing 24 families and 80 genera is dominant. After it follows the temperate type
with 23 families and 50 genera. There are also 4 families endemic to China, i.e. Gin-
kgoaceae, Bretschneideraceae, Eucommiaceae and Davidiaceae. It shows that genera
endemic to China are obviously related to the tropical and temperate flora in essence.
The endemic monotypic genera (139) and endemic obligotypic genera (48) combin-
ed make up more than 95% of the total number of genera endemic to China. Phylo-
genetically more than half of them are ancient or primitive. The life forms of all ende-
mic genera are also diverse. Herbs, especially perennial herbs, prevail with the propor-
tion of about 62%, and trees and shrubs are the next, with 33%, and the rest are lianas.
Based upon the calculated number of genera endemic to China in each province and
the similarity coefficents between any two provinces, some conclusions may be drawn
as follows:
Yunnan and Sichuan Provinces combined are the distribution centre of genera en-
demic to China and may be their original or differentiation area, because numerous
endemic genera, including various groups, exist in these two provinces. The second is
Guizhou where there are 62 endemic genera. Others form a declining order, south
China, central China and east China. But towards the north China endemic genera de-
crease gradually, and the Qinling Range is an important distributional limit.
The largest simitarity coefficient, over 50%, appears between Shaanxi and Gansu
probably because of the Qinling Range linking these two provinces. But between any
other two provinces it is less than 30% and it is generaly larger between two south pro-
vinces than between two north provinces.
These characteristics mentioned above are correlated with topography and climate,
and they may be resulted from the diversification in geography and climatic influence
for a long time. 相似文献
6.
论胡桃科植物的地理分布 总被引:1,自引:0,他引:1
路安民 《中国科学院研究生院学报》1982,20(3):257-274
The present paper aims to discuss the geog raphical distribution of the Juglandaceae
on the basis of unity of the phylogeny and the process of dispersal in the plants.
The paper is divided into the following three parts:
1. The systematic positions and the distribution patterns of nine living genera in
the family Juglandaceae (namely, Engelhardia, Oreomunnea, Alfaroa, Pterocarya, Cyclo-
carya, Juglans, Carya, Annamocarya and Platycarya) are briefly discussed. The evolu-
tional relationships between the different genera of the Juglandaceae are elucidated. The
fossil distribution and the geological date of the plant groups are reviewed. Through
the analysis for the geographical distribution of the Juglandaceous genera, the distribu-
tion patterns may be divided as follows:
A. The tropical distribution pattern
a. The genera of tropical Asia distribution: Engelhardia, Annamocarya.
b. The genera of tropical Central America distribution: Oreomunnea, Alfaroa.
B. The temperate distribution pattern
c. The genus of disjunct distribution between Western Asia and Eastern Asia:
Pterocarya.
d. The genus of disjunct distribution between Eurasia and America: Juglans.
e. The genus of disjunct distribution between Eastern Asia and North America:
Carya.
f. The genera whose distribution is confined to Eastern Asia: Cyclocarya, Platy-
carya.
2. The distribution of species
According to Takhtajan’s view point of phytochoria, the number of species in every
region are counted. It has shown clearily that the Eastern Asian Region and the Coti-
nental South-east Asian Region are most abundant in number of genera and species. Of
the 71 living species, 53 are regional endemic elements, namely 74.6% of the total species.
The author is of the opinion that most endemic species in Eurasia are of old endemic
nature and in America of new endimic nature. There are now 7 genera and 28 species
in China, whose south-western and central parts are most abundant in species, with Pro-
vince Yunnan being richest in genera and species.
3. Discussions of the distribution patterns of the Juglandaceae
A. The centre of floristic region
B. The centre of floristic regions is determined by the following two principles: a.
A large number of species concentrate in a district, namely the centre of the majority;
b. Species of a district can reflect the main stages of the systematic evolution of the
Juglandaceae, namely the centre of diversity. It has shown clearly that the southern
part of Eastern Asian region and the northern part of Continental South-east Asian
Region (i.c. Southern China and Northern Indo-China) are the main distribution centre
of the Juglandaceae, while the southern part of Sonora Region and Caribbean Region
(i.c. South-western U.S.A., Mexico and Central America) are the secondary distribution
centre.
As far as fossil records goes, it has shown that in Tertiary period the Juglanda-
ceae were widely distributed in northern Eurasia and North America, growing not only
in Europe and the Caucasus but also as far as in Greenland and Alaska. It may be
considered that the Juglandaceae might be originated from Laurasia. According to
the analysis of distribution pattern for living primitive genus, for example, Engelhar-
dia, South-western China and Northern Indo-China may be the birthplace of the most
primitive Juglandaceous plants. It also can be seen that the primitive genera and the
primitive sections of every genus in the Juglandaceae have mostly distributed in the
tropics or subtropics. At the same time, according to the analysis of morphological cha-
racters, such as naked buds in the primitive taxa of this family, it is considered that
this character has relationship with the living conditions of their ancestors. All the
evidence seems to show that the Juglandaceae are of forest origin in the tropical moun-
tains having seasonal drying period.
B. The time of the origin
The geological times of fossil records are analyzed. It is concluded that the origin
of the Juglandaceae dates back at least as early as the Cretaceous period.
C. The routes of despersal
After the emergence of the Juglandaceous plant on earth, it had first developed and
dispersed in Southern China and Indo-China. Under conditions of the stable tempera-
ture and humidity in North Hemisphere during the period of its origin and development,
the Juglandaceous plants had rapidly developed and distributed in Eurasia and dis-
persed to North America by two routes: Europe-Greenland-North America route and
Asia-Bering Land-bridge-North America route. From Central America it later reached
South America.
D. The formaation of the modern distribution pattern and reasons for this forma-
tion.
According to the fossil records, the formation of two disjunct areas was not due to
the origin of synchronous development, nor to the parallel evolution in the two con-
tinents of Eurasia and America, nor can it be interpreted as due to result of transmis-
sive function. The modern distribution pattern has developed as a result of the tectonic
movement and of the climatic change after the Tertiary period. Because of the con-
tinental drift, the Eurasian Continent was separated from the North American Conti-
nent, it had formed a disjunction between Eurasia and North America. Especially, under
the glaciation during the Late Tertiary and Quaternary Periods, the continents in Eu-
rasia and North America were covered by ice sheet with the exception of “plant refuges”, most plants in the area were destroyed, but the southern part of Eastern Asia
remained practically intact and most of the plants including the Juglandaceae were
preserved from destruction by ice and thence became a main centre of survival in the
North Hemisphere, likewise, there is another centre of survival in the same latitude in
North America and Central America.
E. Finally, the probable evolutionary relationships of the genera of the Juglanda-ceae is presented by the dendrogram in the text. 相似文献
7.
张志耘 《中国科学院研究生院学报》1988,26(5):394-403
The morphological characters in the genus Orobanche were evaluated from the
taxonomic point of view. The author finds that the plants of this genus are relatively similar
to each other in respect to characters of vegetative organs, fruits and seeds. But the differences
in the floral structures can be served as a basis for delimitating infrageneric taxa. The seed
coat of 18 species and pollen grains of 6 species were also examined under scanning electron
microscope (SEM). They seem to have little significance for distinguishing species.
The result supports G. Beck’s (1930) division of the genus Orobanche into 4 sections, of
which 2 occur in China, based on the characters of the inflorescence, bracteoles and calyx.
The author considers that some characters, such as anther hairy or not, upper lip of corolla
entire or not, lower lip longer or shorter than the upper one, the state of corolla-tube inflec-
tion and the hair type of filaments and plants, are important in distinguishing Chinese species.
A key to the species of Orobanche in China is given.
This genus consists of about 100 species, and is mostly confined to Eurasia, with over 60
species found in Caucasus and Middle Asia of USSR, where may be the mordern distribu-
tional centre.
Orobanche L. in China is represented by 23 species, 3 varieties and l forma. As shown in
Table 1, most species (12 species) are found in Xinjiang, which clearly shows a close floristic
relationship between this region and Middle Asia of USSR. 6 species are endemic to China,
of which 4 are confined to the Hengduan Mountains (Yangtze-Mekong-Salwin divide).
The relationships between this genus and related ones of Orobanchaceae are also discussed.
The author holds the following opinions: the genus Phelypaea Desf. should be considered as a
member of Orobanche L. Sect. Gymnocaulis G. Beck, the monotypic genus, Necranthus A.
Gilli endemic to Turkey, is allied with Orobanche L. Sect. Orobanche, the monotypic genus,
Platypholis Maxim, endemic to Bonin Is. of Japan, is far from Orobanche L. in relation and
should be regarded as a separate genus.
The 11 OTU’s, including all the sections of Orobanche L. and 7 genera of Orobanchaceae,
and 15 morphological characters were used in the numerical taxonomic treatment to test the
above-mentioned suggestions. After standardization of characters, the correlation matrices were
computerized. The correlation matrices were made to test the various clustering methods. At
last the UPGMA clustering method was chosen and its result is shown in a phenogram. The
result of numerical analysis is basically in accordance with the suggestions. 相似文献
8.
我国悬钩子属植物的研究 总被引:1,自引:0,他引:1
陆玲娣 《中国科学院研究生院学报》1983,21(1):13-25
The genus Rubus is one of the largest genera in the Rosaceae, consisting of more
than 750 species in many parts of the world, of which 194 species have been recorded
in China.
In the present paper the Rubus is understood in its broad sense, including all the
blackberries, dewberries and raspberries, comprising the woody and herbaceous kinds.
So it is botanically a polymorphic, variable and very complicated group of plants.
The detailed analysis and investigation of the evolutionary trends of the main organs
in this genus have indicated the passage from shrubs to herbs in an evolutionary line,
although there is no obvious discontinuity of morphological characters in various taxa.
From a phylogenetic point of view, the Sect. Idaeobatus Focke is the most primitive
group, characterized by its shrub habit armed with sharp prickles, aciculae or setae,
stipules attached to the petioles, flowers hermaphrodite and often in terminal or axill-
ary inflorescences, very rarely solitary, druplets separated from receptacles. Whereas
the herbaceous Sect. Chamaemorus L. is the most advanced group, which is usually
unarmed, rarely with aciculae or setae, stipules free, flowers dieocious, solitary, dru-
plets adhering to the receptacles and with high chromosome numbers (2n = 56).
Basing upon the evolutionary tendency of morphological features, chromosome nu-
mbers of certain species recorded in literature and the distribution patterns of species,
a new systematic arrangement of Chinese Rubus has been suggested by the present
authors. Focke in his well-known monograph divided the species of Rubus into 12
subgenera, while in the Flora of China 8 sections of Focke were adapted, but some im-
portant revisions have been made in some taxa and Sect. Dalibarda Focke has been
reduced to Sect. Cylactis Focke. In addition, the arrangement of sections is presented
in a reverse order to those of Focke’s system. The species of Rubus in China are
classified into 8 sections with 24 subsections (tab. 3) as follows: 1. Sect. Idaeobatus,
emend. Yü et Lu(11 subsect. 83 sp.); 2. Sect. Lampobatus Focke (1 sp.); 3. Sect.
Rubus (1 sp.); 4. Sect. Malachobatus Focke, emend. Yü et Lu (13 subsect. 85 sp.); 5.
Sect. Dalibardastrus (Focke)Yü et Lu (10 sp.); 6. Sect. Chaemaebatus Focke (5 sp.);
7. Sect. Cylactis Focke, emend. Yü et Lu (8 sp.); 8. Sect. Chamaemorus Focke (1 sp.).
In respect to the geographical distribution the genus Rubus occurs throughout the
world as shown in tab. 2, particularly abundant in the Northern Hemisphere, while
the greatest concentration of species appears in North America and E. Asia. Of the
more than 750 species in the world, 470 or more species (64%) distributed in North
America. It is clearly showm that the center of distribution lies in North America at
present time. There are about 200 species recorded in E. Asia, of which the species
in China (194) amount to 97% of the total number. By analysis of the distribution
of species in China the great majority of them inhabit the southern parts of the Yangtze
River where exist the greatest number of species and endemics, especially in south-
western parts of China, namely Yunnan, Sichuan and Guizhou (tab. 3. 4.). It is in-
teresting to note that the centre of distribution of Rubus in China ranges From north-
western Yunnan to south-western Sichuan (tab. 5), where the genus also reaches its
highest morphological diversity.
In this region the characteristics of floristic elements of Rubus can be summarized
as follows: it is very rich in composition, contaning 6 sections and 94 species, about
66% of the total number of Chinese species; there are also various complex groups,
including primitive, intermediate and advanced taxa of phylogenetic importance; the
proportion of endemic plants is rather high, reaching 61 species, up to 44% of the
total endemics in China. It is noteworthy to note that the most primitive Subsect.
Thyrsidaei (Focke) Yü et Lu, consisting of 9 endemic species, distributed in southern
slopes of the Mts. Qin Ling and Taihang Shan (Fig. 4). From the above facts we may
concluded that the south-western part of China is now not only the center of distribu-
tion and differentiation of Rubus in China, but it may also be the center of origin ofthis genus. 相似文献
9.
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
10.
王文采 《中国科学院研究生院学报》1980,18(3):266-282
1. Having analyzed the external morphology of the genus Microula, the author
has proposed a series of criteria as bases for the construction of a classification scheme
of this genus. The most important ones are as follows:
1) The normally developed stem is primitive, and the strongly abbreviated stem
more advanced.
2) The small inconspicuous bracts are more primitive than the large suborbicular
densely arranged ones, which almost entirely cover the flowers and the fruits.
3) Nutlets with small dorsal pit are more primitive than those with larger pit
on one hand or those without it on the other.
4) The dorsal pit with simple margin precedes that with double margins.
5) Nutlets with subbasal areola precede those with lateral or apical areola.
6) Nutlets without glochids precede those with glochids.
2. Basing upon these criteria the genus Microula may be divided into six sections.
The section Schistocaryum may be the primitive one, and the others may be evolved
from it respectively. The possible affinities between them are demonstrated in figure
no. two.
3. The genus Microula, containing 30 species, is mainly distributed in the
Chinghai-Tibetan plateau and the majority of its species concentrates in the eastern
border of the plateau, and of the 30 species 26—that is 90 percent—are endemic
to China, and the remaining 4 are distributed elsewhere in China, too, and extending
southward and westward to Bhutan, Sikkim, Nepal and Kashmir respectively. In the
region between Heishui, Province Szechuan, and Chinghai Lake there are 9 species,
which, curiously, represent all the six sections of Microula, hence this region seems to
be the center of maximum variation of this genus. M. ovalifolia whose nutlets have
small dorsal pit and subbasal areola may be considered the most primitive species.
Thus the author is of the opinion that the western part of province Szechuan, to
which M. ovalifolia is endemic, may probably be the center of origin of the genusMicroula. 相似文献
11.
比较了反射仪—K+试纸法(K+ts-fl)、原子吸收光谱法、ICP–aeS法测定烟株叶脉汁液中的K+含量的三种方法,确定反射仪—K+试纸法测定烟株钾含量的可行性及其最佳测定范围;在烤烟不同生育期,应用反射仪—K+试纸法对烟株叶片不同部位含K+水平的测定,确定其最佳测定时期及部位。研究结果表明,反射仪—K+试纸法与原子吸收光谱法、ICP–aeS法测定结果差异不显著,应用反射仪—K+试纸法进行烟株钾素快速诊断可行,且具有时间短,简单快速,易操作等优点。反射仪测定K+的稳定线性范围是0.30g/L~0.9g/L;在不同时期对烟株不同部位测定研究表明,最佳诊断部位为烟株第二平展叶叶脉基部2cm段。 相似文献
12.
在扫描电镜下系统研究了木兰科10属52种成熟种子内种皮合点区形态。该形态分为孔型和管型两大类。孔型为内种皮合点区具一小穿孔。木莲属Manglietia、香木兰属Aromadendron、盖裂木属Talauma(8种)、南洋含笑属Elmerrillia和鹅掌楸属Liriodendron具此类型。管型由内种皮合点区向下凹陷形成的小窝和由窝底向外伸出的小管组成。华盖木属Manglietiastrum、盖裂木属Talauma(3种)、长蕊木兰属Alcimandra、含笑属Michelia、合果木属Paramichelia和观光木属Tsoongiodendron具此类型。在木兰属部分种中还观察到两种形态之间的过渡类型。上述形态特征在属内稳定并为木兰科植物所特有,而且明显表现出原始类群的合点区形态大多为孔型,进化类群的合点区形态大多为管型的特点。 相似文献
13.
本文对我国原始木本被子植物木兰科中的木兰属Magnolia、木莲属Manglietia、含笑属Michelia、
合果木属Paramichelia、观光木属Tsoongioderdron、拟单性木兰属Parakmeria、鹅掌楸属Liriodendron、
华盖木属Manglietiastrum 8属代表种的核型进行了研究。各属代表种的核型公式如下:夜合Magnolia
coco 32m+4sm+2st(2SAT);灰木莲Manglieatia glauca 32m+4sm+2st(2SAT);合果木Paramichelia
baillonii 34m(2SAT)+2sm+2st(2SAT);观光木Tsoongiodendron odorum 32m+6sn(2SAT);拟单性木
兰Parakmeria omeiensis 56m+16sm+4st(2SAT);鹅掌楸Liriodendron chinense 32+4sm(2SAT)+2st
(2SAT);华盖木Manglietiastrum sinicum 28m+4sm+6st(6SAT);白兰 Michelia alba 34m+4sm(2SAT)。作者对木兰科核型进化问题进行了讨论。 相似文献
14.
15.
中国裸子植物分布区的研究(1)——松科植物的地理分布 总被引:3,自引:0,他引:3
应俊生 《中国科学院研究生院学报》1989,27(1):27-38
松科是裸子植物中最大的科,共有10属,约240种。我国有9属,约119种,其中2属
为我国特有属,67种为特有种。 本文概述了我国松科各属的水平分布和垂直分布规律;对各
属分布区进行了对比分析。除油杉属和松属外,其余各属的分布,既不深入到极为干旱的地
区,也不深入到热带山区。本文提出川西滇北地区是松科大部分属的发展中心,同时讨论了某
些属的分布区的退却变化。本文还认为,在目前该科化石资料不十分充足的条件下,要确定松 科及其各属的起源中心,可能性是不大的。 相似文献
16.
中国樟科植物的地理分布 总被引:1,自引:0,他引:1
李锡文 《中国科学院研究生院学报》1979,17(3):24-40
From the study of the geographical distribution of Chinese lauraceous genera and
species, we may concludely obtained some results as follows:
1) Lauraceous family is a pantropical one in distribution, sometimes it may be
reached to the subtropical or temperate zone. There are 18 genera in China natively.
Among them 17 genera are of the tropical distribution-pattern. The tropical Asia dis-
tribution-pattern, i.e. Indo-malaysian distribution-pattern, is the nucleus of Chinese
lauraceous flora. Only 1 genus is of temperate distribution-pattern, i.e. the East Asia-
North America distribution-pattern. From the analysis of the primitive forms and the
concentration of species in these genera, we may regard that: a) All genera of the
tropical distribution-pattern were originated at Gondwana in the past period. South-
western and Southern China may be the birth-land of some genera of tropical distribu-
tion-pattern because it was the northern boundary of Gondwana in the past period.
b) The genus of temperate distribution-pattern may be originated in the montane
region of Western or South-western China.
2) Yunnan, Guangdong, Guangxi and Sichuan are the provinces having laura-
ceous species in abundance. But the provinces having lauraceous endemic species in
abundance are Yunnan, Guangdong, Taiwan,, Guangxi and Sichuan. In general Chinese
lauraceous plants are distributed mainly in south-western and southern parts of China.
The southeastern and southern parts of province Yunnan are of great abundance in
lauraceous species or endemic species. The species amount of lauraceous species in
these two parts of Yunnan is 67.3% of the total species amount of the lauraceous
flora in that province. It may be explained by the fact that a) where it is of existence
of primary forest, b)of great specific endemism in the rocky region and c) the
passway in migration of lauraceous plant from east to west or reverse.
3) The great similarity of lauraceous flora between Yunnan (especially its
western or north-western part) and Xizang (especially its southern or south-eastern
part), as well as between Guangdong and Guangxi, may be exhibited by the background
in perfect harmony of each own flora with environment in the past period. The en-
demism of lauraceous flora in Taiwan and Hainan is manifest from the standpoint of
island's isolation. But the latter is of a more manifest one, because it is situated at
the southern latitude and is more adaptive to the development of lauraceous plant.
4) The deciduous species of lauraceous plant which are the principal elements
in the flora of subtropical or temperate zone, are mainly of inland distribution-pattern.
Their geographical distribution are more concentrated at the montane region of
Western or South-western China. Where it may be the birth-land of the subtropical
or temperate lauraceous species, or even of the whole temperate flora.
相似文献
17.
马兜铃科的地理分布及其系统 总被引:1,自引:0,他引:1
马金双 《中国科学院研究生院学报》1990,28(5):345-355
马兜铃科基本是一个热带科。 东亚的横断山至华南一带是其原始分布与分化中心,热带美洲是其次生分布与分化中心。科的形态演化趋势是花被由分化的双被到不分化的单被,由分离到合生,由杯状到管状;雄蕊由多数到少数,由分离到与雌蕊结合成为合蕊柱;于房由半下位到完全下位;果实由蓇葖状蒴果到蒴果。马兜铃科分2亚科4族6属。 相似文献
18.
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。 相似文献