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201.
The Aquilapolles are found in Northeast and Eastern part of China. 183 speices are selected from the world. These 183 speices include Aquilapollenites, Mancicorpus, Fibulapollis and Translucentipollis. It is showed that they appeared from Albian of Early Cretaceous to Early Oligocene(?) of Tertiary. They mainly appeared in Senonian. The Aquilapolles are the most flourishing in Cretaceous during Maestrichtian. Tile six speices of which appeared in Tertiary. They are Aquilapollenites granobaculus, A. punctatus, A. quadrilobus, A. spinulosus, Funk., A. spinulosus (Mtched.) n. corab. and Fibulapollis mirificus. There are two phytogeoprovinces of the sporo-pollen in the Northern Hemisphere during Late Cretaceous. One is "Aquilapolles District "-moist subtropical climatic, Circum-Pacific and Siberia. Another is “Normapolles District”-arid (or semiarid) sub- tropical climatic, Circum-Atlantic, Europ and India. The author related the process to form the two phytogeopovinees by distribution of continent and sea in that time. In one country, Tertiary Aquilapollenites is wider than Late Cretaceous Aquilapollenites in palaeogeographic range. The Tertiary speices of Aquilapollenites are Aquila-pollenites spinulosus Funk. and A. granobaculus Song in China. Their kinds, amount and distribution fully show an evidence of relict member. They are relict Aquilapollenires and are not recycled fossils .from Upper Cretaceous strata. On Aquilapollenites, the respective characters of the growth and distribution of each Tertiary Epochs are indicated. The author also explores the relations between the growth, distribution and evolution of paleoenvironment in this paper.  相似文献   
202.
This paper deals with the taxonomy and geographic distribution of the genus Chrysosplenium L. in China. Based on the characters and evolution of the seed, capsule, disk, ovary and leaf, the species of this genus can be grouped into 2 subgenera, 5 sections and 16 series. There are 2 subgenera, 5 sections and 11 series in China. They are as follows: I. Subgen. Gamosplenium Maxim. emend. J. T. Pan Leaves alternate. Lectotype: Chrysosplenium carnosum Hook. f. et Thoms. 1. Sect. Alternifolia Franch. emend. J. T. Pan Seeds smooth and glabrous. Type: Chrysosplenium alternifolium L. (1) Ser. Nudicaulia Maxim. emend. J. T. Pan Disk obscure or absent; ovary nearly half-inferior, sometimes mostly inferior; capsule generally subtruncate and emarginate at top and bilobed with equal and horizontally divaricate or suberect lobes; seeds smooth and glabrous. Type: Chrysosplenium nudicaule Maxim. (2) Ser. Alternifolia Maxim. emend. J. T. Pan Disk 8-lobed; ovary nearly half-inferior; capsule generally subtruncate and emarginate at top, and bilobed with equal and horizontally divaricate lobes; seeds smooth and glabrous. Type: Chrysosplenium alternifolia L. 2. Sect. Nephrophylloides Turcz. Seeds minutely papillose or pilose. Type: Chrysosplenium sedakowii Turcz. (1) Ser. Macrophylla Franch. emend. J. T. Pan Disk obscure or absent; ovary nearly half-inferior; capsule nearly truncate and emarginate at top, and bilobed with equal lobes; seeds minutely papillose. Type: Chrysosplenium macrophyllum Oliv. (2) Ser. Ovalifolia Maxim. emend. J. T. Pan Disk generally 8-, rarely 4-, lobed, papillae absent around disk; ovary mostly inferior; capsule subtruncate and emarginate at top; seeds minutely papillose or pilose. Type: Chrysosplenium ovalifolium M. Bieb. ex Bunge (3) Ser. Lanuginosa Hara, emend. J. T. Pan Papillae numerous, brown around reduced disk; ovary mostly inferior; capsule nearly truncate and emarginate at top; seeds minutely papillose. Type: Chrysosplenium lanuginosum Hook. f. et Thoms. II. Subgen. Chrysosplenium Leaves opposite. Type: Chrysosplenium oppositifolium L. 1. Sect. Trichosperma J. T. Pan, sect. nov. Capsule not truncate at top, and bilobed with subequal, suberect or divergent lobes. Type: Chrysosplenium trichospermum Edgew. ex Hook. f. et Thoms. This section is divided into 4 series in the world, with only 1 in China. (1) Ser. Nepalensia Maxim. emend. J. T. Pan Disk obscure or absent; ovary generally mostly inferior; cassule not truncate at top, and bilobed with subequal and suberect or divergent lobes; seeds smooth and glabrous. Type: Chrysosplenium nepalense D. Don 2. Sect. Grayana J. T. Pan, sect. nov. Capsule bilobed with distinctly unequal and ascending lobes. Type: Chrysosplenium grayanum Maxim. This section consists of 4 series in the world, with 3 series in China. (1) Ser. Sinica Maxim. emend. J. T. Pan Disk obscure or absent; ovary nearly half-superior; capsule bilobed with distinctly unequal and ascending lobes; seeds minutely papillose. Type: Chrysosplenium sinicum Maxim. (2) Ser. Esulcata Franch. emend. J. T. Pan Disk (4)-8-lobed; ovary generally half-inferior; capsule bilobed with unequal and ascending lobes; seeds minutely papillose or pilose. Lectotype: Chrysosplenium dubium J. Gayex DC. (3) Ser. pilosa maxim. emend. J. T. Pan Disk obscure or absent; ovary nearly half-inferior; capsule bilobed with distinctly unequal and ascending lobes; seeds distinctly longitudinally ll-18-costate and minutely papillose or tuberculate on the ridge. Type: Chrysosplenium pilosum Maxim. 3. Sect. Chrysosplenium Capsule nearly truncate and emarginate at top, and bilobed with equal and horizontally divaricate lobes. Type: Chrysosplenium oppositifolium L. (1) Ser. Romosa J. T. Pan, ser. nov. Disk distinctly 8-lobed, papillae sparse, brown around disk; ovary mostly inferior; capsule nearly truncate and emarginate at top, and bilobed with equal and horizontally divaricate lobes; seeds smooth and glabrous. Type: Chrysosplenium ramosum Maxim. This series is monospecific one, also occurring in China, namely C. ramosum Maxim. (2) Ser. Delavayi Hara Disk distinctly 8-lobed, Papillae sparse, brown around the disk; ovary mostly inferior; capsule nearly truncate and emarginate at top, and bilobed with equal and horizontally divaricate lobes; seeds distinctly longitudinally 10-16-costate and transversely striate on the ridge. Type: Chrysosplenium delavayi Franch. This series can be considered as the most advanced one in the Chrysaspleninm L. So far, the Chrysosplenium L. comprises 64 species in the world, among which 1 species is found in North Africa, 2 in South America, 4 in Europe, 5 in North America, 56 in Asia, of which 3 occur in Sikkim, 5 Bhutan, 5 Mongolia, 6 north Burma, 6 Korea, 7 north India, 8 Nepal, 12 Japan, 17 U.S.S.R. (of which 3 also in Europe), 34 China (including 22 endemic species and 3 new species). In China, Fujian and Guangdong Provinces and Zhuang Autonomous Region of Guangxi each has only 1 species, Taiwan, Zhejiang, Shanxi and Hebei Provinces and Uygur Autonomous Region of Xinjiang each has 2, Anhui, Jiangxi and Hunan Provinces each has 3, Qinghai Province 4, Heilongjiang, Liaoning and Guizhou Provinces each has 5, Jilin and Hubei Provinces each has 6, Gausu Province 8, Shaanxi Province and Xizang (Tibet) Autonomous Region each has 10, Yunnan Province has 11, Sichuan Province has 14. Thus the distribution centre of this genus should be in the north temperate zone of Asia, and the region covering Shaanxi Gansu, Sichuan, Yunnan and Xizang may be regarded as an important part of this centre. The 7 species of Ser. Nudicaula Maxim. emend. J. T. Pan can be considered as the most primitive ones in this genus. They are mostly distributed in Shaanxi (Qin Ling), south Gansu, southeast Qinghai, southwest Sichuan and nothwest Yunnan of China. This region may be considered as the centre of the origin (or at least differentiation) of this genus. The new species and the new varieties described in this paper are as follows: C. hydrocotylifolium Levl. et Vant. var. emeiense J. T. Pan, C. taibaishanense J. T. Pan, C. lixianense Jien ex J. T. Pan, C. qinlingense Jien ex J. T. Pan.  相似文献   
203.
The genus Calligonum L. includes a total number of 35 species in the world, of which 24 are in China. They are grouped into four sections, of which Sect. Calliphysae (Fisch. et Mey.) Borszcz. is the most primitive and Sect. Medusae Sosk. et Alexender. is the most progressive. The Calligonum L. is an ancient genus in the arid desert flora, and central Asia is the place of its origin. Some species migrated to the Middle Asia and Iran, developing into a second center there. Also, some newly occurred species of the Middle Asia emigrated eastwards to central Asia, so the genus Calligonum L. in China comprises components of both central Asia and the Middle Asia. The genus Calligonum L. is distributed in North Africa, south Europa and Asia, and China is the eastmost part of the distribution range. They grow in Nei Monggol, Gansu, Qinghai and Xinjiang. There are 12 species in the Zhuengar Basin, covering 50 percent of the total number of species in China, amd thus the genus is the most abundant there.  相似文献   
204.
The classification and the relationships among the genera of Chinese Triticeae were studied based on morphological characters with reference to geographical distribution and habitat conditions. The spike of Triticeae might have been derived from a panicled inflorescence like that in the Bromeae through a racemose inflorescence like the one in the Brachypodieae. There might be three evolutionary lines in the tribe. 1. Pedicels of the panicled inflorescence have become short and bracts decreased in size, which has resulted in a panicled spike with indefinite spikelets or false solitary spikelets at each node of rachis. The middle ribes of both glumes and lemmas and rachilla are not in a single plane. 2. A simple spike with usual solitary spikelets at each node of rachis has been derived from the raceme. The middle ribe of both glumes and lemmas and rachilla are in a single plane. 3. A cymose spike with 3-spikelets at each node of rachis has evolved from the cymose panicle. The glume on the central spikelet is behind the lemma, while those on the lateral spikelets are on lateral sides of the lemmas. From what we have described above Triticeae may be divided into three subtribes: Elyminae, Triticinae and Hordeinae. Then according to the morphological characters of glume, lemma and other organs as well as the habitats and distribution, the native and introduced triticeous plants are classified into 13 genera (Leymus, Elymus, Roegneria, Elytrigia, Aegilops, Triticum, Agropyron, Eremopyrum, Secale, Haynaldia, Psathyrostachys, Hordeum and Hystrix) and their relationships are also discussed meanwhile.  相似文献   
205.
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   
206.
中国油松林生产力格局与模拟   总被引:7,自引:2,他引:5  
基于全国380块样地资料,从宏观上阐明了油松林生物生产力的分布格局,建立了联系叶面积指数分布规律和地植物学知识的生产力水热相关模型与地理分布模型.在油松正常分布范围内(年均气温2~14℃,年降水量400/300~700/900mm),林分叶面积指数随年均气温的变化呈指数递减的函数关系,这是油松林适应水分协迫环境的一种机制.  相似文献   
207.
长喙毛茛泽泻的种群分布格局和群落内种间关联   总被引:10,自引:0,他引:10       下载免费PDF全文
长喙毛茛泽泻茶陵种群呈斑块分布,格局类型为聚集分布型,每个亚种群也呈聚集分布,但聚集强度不同。长喙毛茛泽泻与其几个主要伴生种的相关性经测定结果是:与莼菜及黄花狸藻之间的相关性不显著;与柳叶箬、双穗雀稗及石龙尾之间正相关显著;与疏勿蓼之间负相关显著,长喙毛茛泽泻种子近距离传播以及无性繁殖特性是造成其聚集分布的主要原因。柳叶箬、双穗雀稗和石龙尾对长喙毛茛泽泻具有极强的竞争作用。  相似文献   
208.
对大鲵自然种群在河北省(含京津)分布的质疑   总被引:1,自引:0,他引:1  
在多年对野生动物种群调查的基础上, 通过检索河北省(含京津) 境内92 个市县, 自明清时代至今的近200 卷册地方志和走访有关学者, 分析并确定在河北省境内并无大鲵自然种群的分布。在部分地区偶见大鲵成体, 乃为幼鲵自繁殖地被偶然携带至该地而异地育肥的结果。  相似文献   
209.
In drug discovery, lipophilicity is a key parameter for drug optimization. Lipophilicity determinations can be both work and time consuming, especially for non-UV active compounds. Herein, an improved and simple 1H NMR-based method is described to estimate the lipophilicity at physiological pH (log D7.4) in 1-octanol and D2O buffer. The method can be applied to both UV and non-UV active compounds. In addition, neither calibration curves nor internal/external standards are needed. We have demonstrated that log D7.4 can be accurately measured using 1H NMR for compounds within the log D7.4 interval between 0.7 and 3.3. The method was also compared to a previously described HPLC method.  相似文献   
210.
To avoid unnecessary waste of limited resources and to help prioritize areas for conservation efforts, this study aimed to provide information on habitat use by elephants between the wet and dry seasons in the Mole National Park (MNP) of Ghana. We compiled coordinates of 516 locations of elephants’ encounters, 256 for dry season and 260 for wet season. Using nine predictor variables, we modeled the probability of elephant's distribution in MNP. We threshold the models to “suitable” and “nonsuitable” regions of habitat use using the equal training sensitivity and specificity values of 0.177 and 0.181 for the dry and wet seasons, respectively. Accuracy assessment of our models revealed a sensitivity score of 0.909 and 0.974, and a specificity of 0.579 and 0.753 for the dry and wet seasons, respectively. A TSS of 0.488 was also recorded for the dry season and 0.727 for the wet season indicating a good model agreement. Our model predicts habitat use to be confined to the southern portion of MNP due to elevation difference and a relatively steep slope that separates the northern regions of the park from the south. Regions of habitat use for the wet season were 856 km2 and reduced significantly to 547.68 km2 in the dry season. We observed significant overlap (327.24 km2) in habitat use regions between the wet and dry seasons (Schoener's D = 0.922 and Hellinger's‐based I = 0.991). DEM, proximity to waterholes, and saltlicks were identified as the key variables that contributed to the prediction. We recommend construction of temporal camps in regions of habitat use that are far from the headquarters area for effective management of elephants. Also, an increase in water point's density around the headquarters areas and selected dry areas of the park will further decrease elephant's range and hence a relatively less resource use in monitoring and patrols.  相似文献   
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