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121.
Hong Qian 《Journal of Biogeography》2019,46(5):1096-1099
In their recent paper published in Nature (2018, 554, 234‐238), Lu et al. use phylogenetic approaches to determine the proportion of the Chinese angiosperm genera that originated during the Miocene or later, and contrast divergence times and phylogenetic dispersion between eastern and western China. One of their key conclusions is that 66% of the angiosperm genera in China originated in the Miocene or later. However, an analysis of 300 angiosperm genera shows that 139 (76.8%) of the 181 genera considered as originating in the Miocene or later by Lu et al. have fossil records before the Miocene. Thus, the evolutionary history of Chinese angiosperm flora has been substantially underestimated in Lu et al. In addition, the results of Lu et al. have been biased by using an incomplete phylogeny. 相似文献
122.
A systematic molecular fragmentation pathway (SMFP) was designed as an identifier to detect swartziarboreols (abieta-8,11,13-triene diterpenoid derivatives) in Swartzia extracts. The SMFP was rationalised through the interpretation of the EI/MS of swartziarboreols isolated from S. arborescens and S. langasdorffii and by analogy with the fragmentations observed for previously isolated compounds. Two pairs of swartziarboreol epimers were identified by GC-MS in an extract of S. langsdorffii using SMFP. Acetylation and methylation of the dichloromethane extract furnished, respectively, 3 and 4, which suggested the occurrence of a new natural orthodiphenolic swartziarboreol. 相似文献
123.
描述了东亚膜翅目茎蜂科两新属:大跗茎蜂属Magnitarsijanus gen.nov.和短痣茎蜂属Stigmatijanus gen.nov.,前者分布于中国和日本,后者分布于中国东部,其模式种分别为Janus kashivorus Yano et Sato,1928和Janus stigmaticus Maa,1949.建立了2个新组合:红盾大跗茎蜂Magnitarsijanus kashivorus(Yano et Sato,1928)comb.nov.和黄鳞短痣茎蜂Stigmatijanus stigmaticus(Maa,1949)comb.nov.,其中红盾大跗茎蜂是中国新纪录种. 相似文献
124.
Mt. Wuyi, located at 27°37‛-27°54‛ N, 117°27‛-117°51‛ E, is the highest mountain
in South-East China. Its main peak, Huanggangshan, is 2158 m above the sea level. In 1955, P.
C. Chen organized the first expedition to Mt. Wuyi, and the authors investigated the different
ravines and the forests of that area in 1976 and from 1979 to 1984 respectively. Up to now
355 species of the bryophytes have been found in Mt. Wuyi.
I. The influence of the factors of geological history on the bryoflora of Mt. Wuyi
Fujian Province, belonging to Cathaysian, one of three Chinese ancient lands, was a part
of ocean until the end of the lower Tertiary. In the early Devonian, Fujian uplifted above the
sea level, but it submerged in the sea later, and then uplifted above the sea level again in the
upper Triassic.
By the end of the lower Triassic the Himalayan movement influenced the paleogeography
of China deeply, and the eastern and central mountains of Fujian uplifted again. In the Tertiary, Fujian was influenced by the hot maritime weather, so the tropical evergreen forests existed
in southern Fujian at that time. The conclusion was made by Z. B. Zhao in 1983 after his long
period of study on geological history of Fujian Province since the Yanshan movement.
According to the morden geographical distribution of Chinese bryophytes, it seems that the
above influence might be related to the bryophytes of Mt. Wuyi and also the southern part of
Zhejian Province. By the end of the Tertiary the weather became cold in most parts of China.
Since then the cold weather and hot weather alternated several times. One kind of the endemic elements of the bryoflora formed in the area from the south-eastern coast of China to the
southeastern Xizang (Tibet), including Japan. They are not specialized at the family level or
closely related to each other, but they have similar distribution and belong to different families.
In the Quaternary, Mt. Wuyi gradually uplifted following the Himalayan movement. As the
weather cooled down in the upper part of the mountain, deciduous broad-leaved and needleleaved trees increased there. Meanwhile, temperate genera and species of the bryophytes spread and
invaded South China and entered Mr. Wuyi. Rhytidiadelphus and Hvlocomium probably began to grow in Mt. Wuyi at that time, and their distribution is quite different from their primary one. On the other hand, a part of tropical and subtropical bryophytes might enjoy the
changed weather and environment in the Quaternary and existed in a few small localities of Mt.
Wuyi, and the genera Haplomitrium, Endotrichella and Floribundaria are probably their representatives. From the point of view of geological history we are now living in the interglacial
period and the present natural conditions will last continuously, so they will steadily influence
the bryoflora of Mt. Wuyi in a long period of time.
2. Essential characteristics of the bryoflora in Mt. Wuyi
Due to the geographical position and the other factors of Mt. Wuyi the bryoflora is represented by numerous tropical and subtropical elements (34.1%), but the East-Asiatic endemic ones
(79.2%) are characteristic of the bryoflora in Mt. Wuyi (Tab. 1). The tropical and subtropical
families of the bryophytes, found south of Changjiang (Yangtzi) River, are Haplomitriaceae (1
genus, 3 species), Porellaceae (2 genera, 8 species), Frullaniaceae (2 genera, 10 species), Lejeun eaceae (21 genera, 35 species), Trachypodaceae (3 genera, 4 species), Meteoriaceae (10 genera, 17
species), Neckeraceae (5 genera, 8 species) and Hookeriaceae (3 genera, 3 species). The above
8 families, including 46 genera and 85 species, represent about 1/4 genera (24.3%) and less than
1/4 species (23.9%) of the bryoflora of Mt. Wuyi.
Most species of East-Asiatic elements show very close relationships with Japan, and are
widely distributed from the low altitude of Mt. Wuyi to the summit of Mt. Huanggangshan.
However, the Holarctic species (26.8%) are also important elements of the bryoflora in Mt.
Wuyi, showing its transition nature, although it is located in the subtropics. Moreover, the in fluence of the Himalayas also exists in Mt. Wuyi, and the Himalayan elements cover 14.4% in
the bryoflora of Mt. Wuyi. The similarity coefficients between the bryofloras of Central and
South America, Africa and Oceania and that of Mt. Wuyi are from 5.0-9.2% respectively. The
endemic species are not very many and cosmopolitan species are only 7 there.
In 1958, P. C. Chen designated Mt. Wuyi as “the transition region of South and North
China rich in East-Asiatic genera and species”. His very important conclusion is essentially in
accordance with the fact of the bryoflora on Mt. Wuyi. Recently, some of the new records fur ther show the characteristics of the bryoflora in Wuyi. Two facts are worth being mentioned.
One is that East-Asiatic genera are only five in Mt. Wuyi. However, there are 9 East-Asiatic
genera in Mt. Huangshan more than in Mt. Wuyi; 4 East-Asiatic genera are recorded in Mt.
Shennongjia. The other is that epiphyllous liverworts in Mt. Wuyi, consisting of 7 families, 21
genera and 36 species, are less than on Hainan Island and Xishuangbannan, located in the tro pics in China.
3. Comparison between the bryoflora of Mt. Wuyi and those of the neighbouring regions
As China covers a very large area, bryofloristic elements are quite different in the diffe rent regions. In this section, we are concentrated on making a comparison between the bryof loras of Mt. Wuyi and the regions belonging to the Central China of the bryoflora named by
P. C. Chen.
Huaping Forest Region, Guangxi Zhuang Autonomous Region in South China, with both
latitute and altitude very similar to Mt. Wuyi, is included in this comparison (Fig. 1). According to the rough estimation, the similarity coefficient of moss genera between Mt. Wuyi and
Huaping is 56.3%, and those between the mountain and southern Zhejian and Mt. Huangshan,
Anhui, are 62.7% and 51.6% respectively, while the similarity coefficient of the genera of the
mossfloras between Mt. Shennongjia and Mt. Wuyi is 46.8%. Table 2 shows the statistics of
mosses in Mt. Wuyi and the others, but the bryoflora of Huaping needs further study However,
it is very interesting to note that Haplomitrium and Pleurozia of liverworts are both found in
Mt. Wuyi and Huaping Forest Region, and the similarity coefficient between the mossfloras of
Mt. Wuyi and Zhejian Province is also higher than those mentioned above.
Tropical and subtropical elements reduce towards the north in China, and temperate ones
increase. Huaping is located in the south, and, as expected, some tropical and subtropical
genera such as Hookeriopsis and Symphyodon have been found there, but not in Mt. Wuyi; several
temperate genera, such as Schwetschkeopsis and Fauriella, have been recorded in Mt. Huangshan,
but not in Mt. Wuyi. For some unknown reasons, Octoblepharum and Neckeropsis are only
found in southern Zhejiang, but not in Mt. Wuyi. Mt. Shennongjia, with its main peak over
1000 m higher than that of Mt. Wuyi, is located in its northwest, and more than ten temperate
genera, such as, Ceratodon, Aulacomnium Myurella, Bryonoguchia and Abietinella have been
found there.
Generally, Mt. Wuyi belongs to the central subtropical region of China, and East-Asiatic
endemic genera are the main elements of its bryoflora, but the bryoflora also consists of tropical and subtropical elements with some temperate ones.
4. East-Asiatic endemic genera in the bryoflora of Mt. Wuyi
In the bryoflora of Mt. Wuyi, one of the main elements, East-Asiatic endemic genera, should
not be neglected (Tab. 4). East-Asiatic endemic genera in Mt. Wuyi (five) are less than in Mt.
Huangshan and Mt. West Tianmu, although the positions of the latter two are very close to Mt.
Wuyi. East-Asiatic endemic genera of liverworts are Trichocolea and Macvicaria so far found
in Mt. Wuyi, and the mosses are Myuriopsis, Meteoriella, Pseudospiridentopsis (Fig. 1). Myuriopsis is only distributed in Taiwan Province and Mt. Wuyi, and the other four are distributed in Mt.
Huangshan or Mt. West Tianmu, and also in Taiwan, besides in Mt. Wuyi. About thirty EastAsiatic endemic genera have so far been known in China, which means that about one sixth of
East- Asiatic endemic genera of the bryophytes occur in Mt. Wuyi. We may notice that nine
and seven East-Asiatic endemic genera of the bryophytes have been recorded in Mt. Huangshan
and Mt. West Tianmu respectively. In Mt. Shennongjia, Central China, there are four East
Asiatic endemic genera, but only two have been found in the Huaping Forest Region, South
China. In Mt. Dinghua, located south of Mt. Wuyi, on East-Asiatic endemic genus of the bryophytes has so far been found.
East-Asiatic endemic genera of the bryophytes are mainly limited to China, Korea and Japan,
including the East Himalayas, rarely occur in South Asia, Siberia of the Soviet Union. Therefore,
these genera enjoy a warm and moist environment. In Mt. Wuyi, all the East-Asiatic endemic
genera are monotypic ones with a disjunct distribution. Now in Taiwan Province five of six
recorded East-Asiatic endemic genera are common to Mt. Wuyi. In Japan, about eleven, i.e.
one third of, East Asiatic endemic genera so far found are common to China, which shows a
long history of the phytogeographical relationships between Japan and China. East Asiatic endemic genera of the bryophytes might therefore exist on islands of Taiwan Province and Japan
before they were separated from the mainland of Asia. However the fossil evidence is still
lacking in the bryophytes, so we are not able to discuss about the distribution area and the distribution center of the East-Asiatic bryoflora in detail. The above estimation is more or less
related to geological history, and we assume that the East-Asiatic endemic genera have existed at
least since the end of the Tertiary. Starting from the Quaternary, the climatic change during
glacial epoch has been possibly the most important factor affecting the bryoflora in Asia, and
the upheaval of the Himalayas has stimulated the diversity and the specialization of the bryophy tes. Considering these factors, East-Asiatic endemic genera might be the “Tertiary fossil
plants”.
Another problem is difficult to explain, because Mts. Huangshan, West Tianmu and Shen nongjia were once influenced by glaciation directly, although Chinese geologists hold different
views. However, no evidence of glaciation has been found in Mt. Wuyi. It is worth to study the
close relationships between Mt. Wuyi, Mt. Huangshan and Mt. West Tianmu, where is the distri bution center of the East-Asiatic endemic genera. The above three mountain regions share half
of the East-Asiatic endemic genera, and about 32% genera of the others are found in two of
them (Fig. 2). Myuriopsis, one of the East Asiatic types, was only recorded in Taiwan Pro vince, Japan and Korea. Neodolichomitra, occuring in Taiwan Province, is endemic to China.
More or less the differentiation has taken place in Mt. Huangshan, Mt. West Tianmu and Mt.
Wuyi. The number of the East-Asiatic endemic genera is smaller in Mt. Wuyi, so it is possibly
located on the border of the distributional center of the East-Asiatic endemic genera. Moreo ver, three of four East-Asiatic endemic genera in Mt. Shennongjia are also found in Mt. Huang shan and Mt. West Tianmu, but the other East-Asiatic genus in Mt. Wuyi is common to the
mountain areas in SW China, the Qinglin Range of NW China, and the isolated mountain areas
of NE China. Considering all the characteristics of the bryoflora of Mt. Shennongjia, we assume
that Mt. Shennongjia may belong to another distribution center, including SW part of Sichuan
Province, and the other neighbouring mountains. 相似文献
125.
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
126.
China, under highly varied ecological conditions resulted from wide latitudinal and altitudinal ranges and from the adequate precipitation, has developed a
very rich flora of great diversity. As far as flowering plants are concerned, there are
2980 genera, 214 of which, belonging to 64 families, are endemic. Among these endemic genera, there are 9 genera of taxads and conifers, 19 genera of monocots and
others of dicots. Of the approximately 129 herbaceous endemic genera in the Chinese
flora as a whole, about 22 (17%) are annual and 107 (83%) are biennial or perennial.
In the present paper the ecological distribution, the nature of endemic genera and the
centers of endemism are discussed.
1. Three types of endemic genera are distinguished, neoendemics, palaeoendemics
and active epibiotics, The endemic genera in the flora of China are, for the most part,
considered to be very old ones, and most of them are of temperate nature.
2. the degree of endemism in our 22 floristic regions is shown in Figure 1. The
areas richest in endemic genera in the Chinese flora as a whole are the 13, 16 and 17
regions. The poorest are the 2, 4, 9 and 10 regions, and no one in the 1 and 3 regions
These results on floristic richness are of general applicability.
As shown in table 1, the difference in the degree of endemism among the seven
Chinese floristic subkingdoms are most pronounced. 101 endemic genera are known
to occur in one subkingdom, 72 to occur in two subkingdoms, and 3 to occur in four
subkingdoms, only one genus widely distributed in five subkingdoms. However, there
is no genus occurring in seven subkingdoms. The difference in the degree of endemism
in each subkingdom reveals that the distribution of endemic genera is not well-distributed in the Chinese flora as a whole.
Analysis of the vertical distribution of the 200 endemic genera of the Chinese
flora bears out that there is no evident increase in endemism as a whole with altitude.
3. Three centers of endemism are found (Fig. 2). These are as follows:
a). Eastern Sichuan-western Hubei center.
b). Southeastern Yunnan-western Guangxi center.
c). Western Sichuan-northwestern Yunnan center. The degree of endemism andcharacters of endemic genera in each center are discussed. 相似文献
127.
128.
中国东北样带树种(属)的空间特性及变化 总被引:1,自引:0,他引:1
The 16 tree species on Northeast China Transect (NECT) were analyzed from the change of geographical distribution, frequency and dominance pattern and the spatial correlation at landscape scale in 1986 and 1994. Pinus koraiensis Sieb. et Zucc. and Fraxinus rhynchophylla Hemsl. had spread rapidly towards west and east, respectively. The frontier form of species had close relation with its movement. The patch size of Pinus koraiensis, Populus davidiana Dode., Phellodendron amurense Rupr., Juglans mandshurica Maxim., Fraxinus mandshurica Rupr., Betula dahurica Pall., Picea koraiensis Nakai, Abies nephrolepis Maxim. and Larix olgeusis var. koreana Nakai decreased, however, Quercus mongolica Fisch., Betula costata Trautv., Acer mono Maxim., Tilia spp., Ulmus spp., Betula platyphylla Suk. and Fraxinus rhynchophylla increased. The frequency pattern of Populus davidiana, Betula platyphylla, Fraxinus rhynchophylla and Betula dahurica changed significantly. The dominance pattern of Populus davidiana, Tilia spp., Juglans mandshurica, Betula platyphylla, Betula dahurica and Abies nephrolepis changed significantly. The spatial correlation between Quercus mongolica and Betula dahurica, Betula costata and Picea spp., Betula costata and Abies nephrolepis, Picea spp. and Abies nephrolepis declined, however, the spatial correlation between Larix spp. and Betula platyphylla, Acer mono and Ulmus spp. increased. 相似文献
129.
130.
Yushan Zhang Mengting Chen Jingyi Guo Ning Liu Weiyi Yi Zhongtai Yuan Lifan Zeng 《Engineering in Life Science》2022,22(5):376
There are few reports on the material transformation and dominant microorganisms in the process of greening waste (GW) composting. In this study, the target microbial community succession and material transformation were studied in GW composting by using MiSeq sequencing and PICRUSt tools. The results showed that the composting process could be divided into four phases. Each phase of the composting appeared in turn and was unable to jump. In the calefactive phase, microorganisms decompose small molecular organics such as FA to accelerate the arrival of the thermophilic phase. In the thermophilic phase, thermophilic microorganisms decompose HA and lignocellulose to produce FA. While in the cooling phase, microorganisms degrade HA and FA for growth and reproduction. In the maturation phase, microorganisms synthesize humus using FA, amino acid and lignin nuclei as precursors. In the four phases of the composting, different representative genera of bacteria and fungi were detected. Streptomyces, Myceliophthora and Aspergillus, maintained high abundance in all phases of the compost. Correlation analysis indicated that bacteria, actinomycetes and fungi had synergistic effect on the degradation of lignocellulose. Therefore, it can accelerate the compost process by maintaining the thermophilic phase and adding a certain amount of FA in the maturation phase. 相似文献