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Ectoparasites have been investigated on gills of the ruff, perch, white bream, roach, bream, ide, and European cisco from the Pleshcheevo lake. 13 parasite species were found: Dactylogyrus falcatus, D. distinguendus, D. cornoides, D. cornu, D. sphyrna, D. robustus, D. amphibothrium, Ancyrocephalus paradoxus, Argulus foliaceus, Ergasilus sieboldi, Achtheres percarum, Ancyrocephalus percae, and Rhipidocotyle companula. A reliable negative correlation between the number of monogeneans An. paradoxus and the copepods Ac. percarum on the perch. D. falcatus, the specific monogenean of the bream, was found on the roach. The comparison of the obtained data with those of 1939 has shown the decrease of oxyphilic copepods E. seiboldi, that prove the increasing eutrophication. 相似文献
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本文研究了新疆准噶尔盆地独山子油田原油中分离出的孢子花粉35属51种。基于原油中孢子花粉的研究,追溯了该含油区的油源并讨论了油气运移问题。根据原油中找到的孢子花粉化石来判断,准噶尔盆地西南含油区有两套油源岩系,即下一中侏罗统八道湾一头屯河组和渐新统安集海河组。 相似文献
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Forty-six species of fossil spores and pollen referred to 30 genera extracted from the crude oil samples collected from the Kashi Depression of the Tarim Basin in Xinjiang were recorded . Based on the investigations of the palynomorphs in crude oil. the petroleum source of the petroliferous region was traced and the petroleum migration mechanism is discussed. The fossil spores and pollen found from crude oil of the Neogene reservoir of the Kelatuo Oilfield of the Kashi Depression comprised mainly Deltoidospora lineata, Cyathidites australis, C. minor, Gleicheniidites rousei, Dictyophyllidites harrisii, Cibothtmspora paradoxa, Todisporites major, Granulatisporites minor, Leptolepidites major, Klukisporites variegatus, Murospora jurassica, M. minor, Paleoconiferus asaccatus, Vi!reisporites jurassicus, V. shouldicei, V. jansonii, Alisporites thomasii, A. lowoodensis, Podocarpidites florinii, P. langii, P. multicinus, P. multesimus. Quadraeculina limbata, Protopinus scanicus. Protopicea exiliolides, Piceites expositus. P. latens, Pinuspollenites labdacus. Piceaepollenites alatus, Cedripites minor, Chasmatosporites major, C. elegans, C. canadensis, Cycadopites nitidus, C. typicus, Ephedripites tertiarius, CerebropoUenites carlylensis, Classopollis classoides, C. annulatus, Caryapollenites simplex, Chenopodipollis multiplex, Artemisiaepollenes sellularis, etc. According to the characteristics of the petroleum sporo-pollen assemblage, the Lower Jurassic Kangsu Formation and the Middle Jurassic Yangye and Taerga Formations should be the petroleum source rock series of the Kashi Depression. Judging from the palynomorphs of the source rocks found in crude oil. It might be concluded that the fossil spores and pollen together with oil beads must have been expelled from the source rocks along microfissure avenuses during the primary migration along fissures, joints faults, and unconformity planes during the secondary migration. 相似文献
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略论棕榈科与新分出的省藤科的系统分类、演化、区系地理及主要的经济用途 总被引:6,自引:0,他引:6
棕榈科原省藤亚科因其子房壁及外果皮被倒生、螺旋状排列的鳞片所覆盖,而区别于其他亚科,因而独立分出成一新科--省藤科。作者讨论了棕榈科的祖先种可能在石炭纪时,自原始裸子植物开以顿目在分化、衍生出苏铁目祖先种的进化干上,于白垩纪时分化出的一个分支。在棕榈科的祖先种出现不久后,在其进化的分支上,于白垩纪后期又分化出一旁支,成为棕榈科的姊妹科--省藤科的祖先种。从两祖先种分别再分化、衍生出现今分布地球上该二科的属与种。两科、尤其前者是被子植物、尤其是单子叶植物中最原始的类群之一。作者还提出棕榈科象牙椰亚科与贝叶棕亚科是该科最原始或较原始的两类群;槟榔亚科和腊材榈亚科是较进化的两类群;而水椰亚科祖先种可能源于象牙椰亚科的祖先种,但又演化为该科最进化与特化的类群。省藤科省藤亚科略比鳞果榈亚科原始。作者讨论了两科为泛热带分布的科,指出两科的"现代分布区"在南北两半球热带地区,少数种还延伸分布到两半球暖亚热带、甚至达中亚热带地区,分布区边缘最北达日本中部、中国长江流域及黄河下游的南部,美国加利佛尼亚州与佛罗里达州和地中海北部;最南达智利中部和新西兰南部;而"现代分布中心"在热带与暖亚热带的亚洲,中、南美洲,大洋洲及非洲的东、南、西部;但分布区的"密集中心"则在热带亚洲、热带中及南美洲、南太平洋群岛及非洲东南部。作者还介绍了近50年我国南方引种驯化成功的两科植物近400种(见*图谱),其中少数为耐寒的种类,有的种已引种到长江流域或更北的地区。引种的大部分种都有其重要的经济用途,包括:1. 食用,如淀粉和树液可制"西米"或制糖,酿酒、醋或作饮料;果或种子榨油,供食用或工业用;某些种的嫩芽作蔬菜,甚至种子代咖啡饮用;2. 药用,有消炎、止血、活血、驱虫、抗癌等用;3. 建筑、工艺与日用品,包括不少种的树干供建普通房子、桥梁、小船;少数种可提制工业用蜡;许多种的纤维制高级缆绳和编织品;还制工艺品与日用品等;4. 代表热带景观的园林工程、绿化及美化环境的观赏树和人行道树及建造园林景观生态类型的树种等。 相似文献
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Galán de Mera A Linares Perea E Campos de la Cruz J Vicente Orellana JA 《Revista de biología tropical》2011,59(2):809-828
The vegetation of the sandy hills ("lomas") constitutes the main originality of the Peruvian and Chilean desert with a high number of endemics that shapes the vicarious associations. In this work, a phytosociological view of sandy environments of the Peruvian coastal desert is presented. According to the Braun-Blanquet method, we have made up 32 phytosociological inventories and added 138 ones from others authors. In each inventory, we have analyzed its floristic composition and ecological parameters, as altitude, soil and geomorphology. All releves were synthesized in a table to deduce the different associations, higher phytosociological units, and the distribu tion of its flora along the Peruvian coast and the Andean Cordillera. Using the Shannon-Wiener diversity index, the diversity of this flora is discussed making a comparison with historical data about the use of the territory with livestock during pre-Inca and Inca cultures, and Spanish invasion. As a result, two associations from Southern Peru -Nolanetum scaposo-spathulatae and Palauetum camanensis-weberbaueri-, two alliances -Nolanion humifusae from central Peru, and Nolanion spathulatae from the Southern Peru- and a new order -Tetragonio crystallinae-Plantaginetalia limensis- are described. In Nolanetum scaposo-spathulatae, Dictyophragnus englerianus, Leptoglossis lomana, Nolana scaposa, N. spathulata, Palaua velutina and Tetragonia vestita are the main characteristics, while in Palauetum camanensis-weberbaueri association N. scaposa and P. velutina are replaced by Palaua camanensis and P. weberbaueri. Nolanion humifusae alliance integrates species as Geranium limae, Hymenocallis amancaes, Nolana humifusa, N. latipes, Palaua rhombifolia or Villanova oppositifolia. Likewise, Cistanthe weberbaueri, Cryptantha parviflora, Hoffmannseggia miranda, Lupinus mollendoensis, Nolana confinis, N. pallidula, N. scaposa, N. spathulata, Palaua camanensis, P. velutina, P. weberbaueri, Tetragonia vestita and Weberbauerella brongniartioides are the characteristic species of Nolanion spathulatae alliance. The Tetragonio crystallinae-Plantaginetalia limensis order presents characteristic plants don't linked with eutrophic soils, as Calandrinia alba, Cryptantha limensis, Dyschoriste repens, Monnina macrostachya, Oxalis lomana, Palaua malvifolia, Pectocarya lateriflora, Plantago limensis or Tetragonia crystallina, with a distribution that claps the geographical area of the new alliances. On the other hand, the vegetation of the desert ravines is discussed in the context of the coastal river plant communities and its disturbance by the dunes. After the application of the Shannon-Wiener diversity index on the synthetic table columns, we can deduce that an increase in Andean and European ruderal species is linked to an intensive livestock activity. The transhumance between the Andes and the coast from pre-Inca times until now, produces the plant dispersion of high Andean plants toward the coast; the Spanish colonization was the origin of the presence of European plants in the "lomas" vegetation of Peru. 相似文献
8.
扶桑绵粉蚧的过冷却点和体液结冰点测定 总被引:5,自引:0,他引:5
本文测定了扶桑绵粉蚧Phenacoccus solenopsis Tinsley除卵期以外其它各虫态的过冷却点和结冰点.结果表明,该虫过冷却点以1龄若虫最低,为-24.02℃;雄虫预蛹次之,为-22.13℃;雄虫蛹、雄虫2龄若虫、雌虫3龄若虫、雄成虫、雌虫2龄若虫、雌成虫过冷却点逐渐升高,分别为-21.08℃、-20.25℃、-19.05℃、-18.42℃、-17.91℃、-16.89℃.体液结冰点也以1龄若虫最低,为-23.2℃;雄虫预蛹次之,为-19.09℃;雄虫蛹、雄虫2龄若虫、雌虫3龄若虫、雌虫2龄若虫、雌成虫、雄成虫体液结冰点逐渐升高,分别为-16.64%、-15.81℃、-13.92℃、-13.20℃、-12.85℃、-12.79℃.试验结果表明扶桑绵粉蚧过冷却点低,耐寒性较强,可能适宜在中国北部更广泛的区域生存. 相似文献
9.
本文从生态学观点出发,概述华南藤本植物的区系分布、生物学生态学特性、生长型及参与森林结构的作用,以供有关方面参考。 相似文献
10.
Three new species in Polygonum section Polygonum (Polygonaceae) from Xinjiang, China, are described and illustrated. Polygonum urumqiense F. Z. Li, Y. T. Hou & F. J. Lu is similar to P. aviculare L. in habit, but differs by having flowers densely clustered and spicate in the upper part of branches, stamens 5–6, and two types of achenes (the longer one densely and irregularly granulate on surface). Polygonum tachengense F. Z. Li, Y. T. Hou & F. J. Lu is similar to P. aviculare in the flowers not forming a raceme in the upper part of branches, the stamens 8, and the achenes striate-granulate on surface, but differs by the leaf blades linear-lanceolate, the midvein and lateral veins conspicuously raising abaxially, the ochreae longer, up to 1.1 cm, 15–20-veined, the flowers 3–6 clustered together in the upper axils of branches. This species is also similar to P. patulum M. Bieb. in the erect stem, and the flowers 3–6 clustered together in the axils of the upper part of branches, but differs by the midvein and lateral veins of leaves conspicuously raising abaxially, the ochreae longer, up to 1.1 cm, 15–20-veined, the leaves in the upper part of branches not becoming smaller gradually, and the flowers clustered in the upper axils of branches not forming a raceme, and the achenes striate-granulate on surface. Polygonum shiheziense F. Z. Li, Y. T. Hou & F. J. Lu is similar to P. argyrocoleon Steud. ex Kunze in the erect stem, the 3–6 flowers clustered in the upper axils of branches, the stamens 8, and the slightly smooth achenes, but differs by the midvein and lateral veins of leaves conspicuously raising abaxially, the ochreae longer, up to 1.1 cm, 15–20-veined, and the flowers clustered in the upper axils of branches not forming a raceme. This species is also similar to P. tachengense in habit, but differs in the leaves borne in the upper part of branches becoming smaller gradually and the smooth, slightly shiny achenes. The pollen morphology, leaf epidermal characters and achene micromorphology of the three new species and their relatives were comparatively observed under the scanning electron microscope (SEM). 相似文献
11.
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
12.
One hundred and eight species of fossil spores and pollen referred to 55 genera found from the Lower Cretaceous Kapushaliang (Kizilsu) Group in the Tarim Basin of Xinjiang have been studied in this paper. The Kapushaliang Group may be divided into the Yageliemu Formation, the Shushanhe Formation and Baxigai Formation in ascending order. The Yageliemu palynoflora is characterized by the predominance of gymnospermous pollen, the relative abundance of pteridophytic spores and the absence of angiospermous pollen. Coniferae is dominant, while Lygodiaceae and Schizaeaceae are important in the flora. The most common species of palynomorphs are Todisporites minor, Cicatricosisporites dorogensis, C. australiensis, Lygodiumsporites subsimplex, Schizaeoisporites cretacius, S. zizyphinus, S. certus. Cibotiumspora paradoxa, Cyathidites australis, C. minor, Biretisporites potoniael, Cycadopites minimus, Pseudowalchia hiangulina, Parvisaccites radiatus, Podocarpidites multesimus, P. canadensis, Alisporites bilateralis, Cedripites cretaceus, C. canadenris, Abietineaepollenites microalatus, Clarsopollis classoides, C annulatus, C. xinjiangensis (sp. nov.), Ephedripites multicostatus, E. tarimensis (sp. nov.), etc . The palynoflora is comparable with those of the lower part of the Lower Xinminbu Formation in northwestern China and the lower part of the Lower Mannville Formation in western Canada, which is considered corresponding from Berriasian to Valanginian in age. The Shushanhe palynoflora is also characterized by dominance of gymnosperms and subdominance of pteridophyta. Some primitive angiospermons pollen grains are found in the upper part of the formation. In addition to the most common species of the above mentioned palynoflora, the important species in the present palynoflora comprise Cicatricosisporites potomacensis, C. orbiculatus, C. subrotundus, Concavissimisporites punctatus, C. verrucosus, C. globosus, lmpardecispora apiverrucata, Trilobosporites crassus, T. trioreticulosus, Pilosisporites verus, P. trichopapillosus, Klukisporites pseudoreticulatus, Verrucosisporites obscurilaesuratur, Converrucosisporites saskatchewanensis, Foraminisporis wonthaggiensis, Cingulatisporites valdensis, C. ruginosus, Jiaohepollis verus, Pityosporites constrictus, etc. More than 40 in dicative species of Early Cretaceous occur in the assemblage. The palynoflora compares clcsely with those of the middle part of the Lower Xinminbu Formation and the Quartz Sand Member of the Lower Mannville Formatton. It is suggested that the Shushanhe Formation should belong to Hauterivian of Barremian in age. The Baxigai palynoflora is basically similar to the Shushanhe palynoflora. But the palynoflora shows an obvious increase in abundance of lygodiaceous spores and angiospermous pollen accompanied by a great reduction of Classopollis and Ephedripltes. Most of the Early Cretaceous species occurring in the above mentioned palynofloras are present. In addition, some Cretaceous species recorded from Aptian and Albian Stages in Europe, North America and Australia, such as Trilobosporites tribotrys, T. trioreticulosus, Coptospora paradoxa, Camarozonosporites insignis, Crybelosporites punctatus, etc., appear in the assemblage. In comparison with the microfloras of the upper part of the Lower Xinminbu Formation, the Upper Mannville Formation and the lower part of the Lower Colorado Group, the Baxigai Forma- tion should be referred to Aptian to Albian in age. Judging from the palynofloras, the early Cretaceous palaeoclimate in the basin should belong to the arid or semi-arid type of the subtropic zone. However, from Barremtan through Albian the climatic conditions might appear relatively wet. 相似文献
13.
红原鸡全基因组中微卫星分布规律研究 总被引:1,自引:0,他引:1
本文对红原鸡Gallus gallus全基因组中微卫星数量及分布规律进行了分析,查找到l~6个碱基重复类型的微卫星序列共282728个,约占全基因组序列(1.1Gb)的0.49%,分布频率为1/3.89kb,微卫星序列的长度主要在12~70个碱基长度范围内。第1、2、3条染色体上微卫星分布频率较高,而32号染色体上无微卫星分布。不同类型微卫星中,单碱基重复类型数目最多,为184192个,占总数的65.1%;其次是四、二、三、五、六碱基重复单元序列,分别占到总数的12.8%、9.7%、7.2%、4.6%、0.8%。T、A、AT、GTTT、AAAC、G、C、ATTT、AC、GT、AAAT、ATT、AAC、AAT、GTT、AG、CT、CTTT、AAAG、GTTTT、AAACA、AAGG、CCTT是红原鸡基因组中最主要的微卫星重复类型。本研究为红原鸡微卫星标记的分离筛选、遗传多样性的研究以及不同物种微卫星的比较分析奠定了基础。 相似文献
14.
15.
Mabuchi Y Shirasawa N Sakuma E Wada I Horiuchi O Kikuchi M Sakamoto A Herbert DC Soji T 《Tissue & cell》2008,40(3):157-166
Since [Westlud, K.N., Chils, G.V., 1982. Localization of serotonin fibers in the rat adenohypophysis. Endocrinology 111, 1761-1763] initially identified the serotonin nerve fibers in the anterior pituitary gland, attention has been paid to the rostral zone of the anterior lobe into which nerve fibers enter and subsequently spread to deeper regions of the lobe. The rostral zone is the trifurcated junction of the partes tuberalis, intermedia and distalis, and has the important role(s) for hormone secretion via the "transitional zone" [Sato, G, Shirasawa, N, Sakuma, E, Sato, Y, Asai, Y, Wada, I, Horiuchi, O, Sakamoto, A, Herbert, DC, Soji, T, 2005a. Intercellular communications within the rat anterior pituitary. XI: An immunohistochemical study of distributions of S-100 positive cells in the anterior pituitary of the rat. Tissue and Cell 37, 269-280.]. The objective of this study was to focus on the ultrastructure of this "zone." All of the animals studied were fixed by perfusion with glutaraldehyde via the left ventricle of the heart and examined by electron microscopy. In the "transitional zone," a cluster of neuronal elements was observed between the folliculo-stellate cell-rich area and the anterior lobe. This cluster consisted of myelinated fibers, unmyelinated fibers, neuroendocrine fibers, large cells, and supporting cells. The large cells were perikarya of neurons which made a "ganglion-like" structure with associated satellite cells. Agranular, folliculo-stellate cells were intermingled among the elements. This is the first report that neuronal elements form clusters in the "transitional zone." A relationship of the unmyelinated and neuroendocrine fibers in the basal layer and in the "transitional zone" is discussed. 相似文献
16.
Cocaine 总被引:1,自引:0,他引:1
M. G. Hadfield 《Molecular neurobiology》1995,11(1-3):47-53
Cocaine HCl (0, 10, or 50 mg/kg) was injected into adult male ICR mice ip. Thirty minutes later, the brains were removed,
and nine regions were isolated: olfactory bulbs, olfactory tubercles, prefrontal cortex, septum, striatum, amygdala, hypothalamus,
hippocampus, and thalamus. Using high-performance liquid chromatography, concentrations of norepinephrine, dopamine, serotonin,
and their major metabolites and the metabolite/neurotransmitter ratios were determined as an indicator of utilization. Serotonergic
systems responded most dramatically. 5HIAA/5-HT decreases were seen in all the brain regions, except the septum, hippocampus,
and olfactory bulbs. In most instances, the alterations were dose-dependent. The most profound changes were seen in the amygdala,
prefrontal cortex, hypothalamus, and thalamus. For noradrenergic systems, significant responses were seen only in the amygdala,
prefrontal cortex, and hypothalamus, but then only at the lower dose. The dopaminergic responses were more complex and not
always dose-dependent. The DOPAC/DA ratio was decreased only in the amygdala and striatum at the lower dose, and the olfactory
tubercles at the higher dose. It was increased in the septum. The HVA/DA ratios were decreased in the amygdala, prefrontal
cortex, and hypothalamus, but only at the lower dose (like MHPG/NE). The 3MT/DA ratio was decreased in the thalamus at the
lower dose and in the olfactory tubercles at the higher dose, whereas it was increased in the prefrontal cortex at the lower
dose. The HVA and DOPAC routes of degradation were both utilized only by the amygdala. Thus, cocaine produced its most comprehensive
effects in this nucleus, as well as the greatest absolute percentage changes for all three of the monoamine systems studied. 相似文献
17.
18.
Sixty-eight species of fossil spores and pollens referred to 39 genera extracted from the crude oil samples collected from the Turpan Basin of Xinjiang are recorded in this paper. Based on the investigations of fossil spores and pollens in petroleum, the questions on petroleum migration and source rocks are discussed. It is expounded and proved theoretically and practically that the phenomenon that the crude oil samples usually contain the fossil spores and pollen grains with different geological ages from reservoir rocks should result from petroleum migration, but not from resedimentation. The fossil spores and pollens in crude oil of the Middle Jurassic reservoir of the Qiktim Oil-Field of the Turpan Basin comprise mainly Leiotriletes pflugi, Deltoidospora gradata, D. magna, Cyathidites australir, C. minor, Biretisporites cf. potoniaei, Dictyophyllidites harrisii. Cibotiumspora paradoxa, C. jurienensis, Gleicheniidites rousei, G. conflexus, Undulatisporites concavus, U. pflugii, Granulatisporites arenaster, G. minor, Todisporites minor, Osmundacidites wellmanii, dpiculatisporis variabilis, Leptolepidites major, Aratrisporites scabratus Cycadopites nitidus, C. typicus, C. subgranulosus, Chasmatosporites elegans, Classopollis classoides, C. itunen- sis, C. annulatus, C. qiyangensis, Callialarporites dampieri, C. radius, lnaperturopollenites det- tmannii, Protoconiferus funarius, Paleoconiferus asaccatus, CaytonipoUenites pallidus, Vitreis- porites jurassicus, V. jansonii, Pseudowalchia ovalis, P. landesii, P. biangulina, Podocarpidites unicus, P. major, P. multicinus, P. multesimus, P. rousei, P. wapellaensis, Platysaccus lopsinensis, Ovalipollis enigmatica, O. minor, O. canadensis, Pteruchipollenites thomasii, Alisporites grandis, A. bilateralis, Pityosporites similis, P. divulgatus, Piceites expos us, P. podocarpoides, P. latens, Protopicea exilioides, Pseudopicea variabitifornus, Piceaepollenites complanatiformus, Abietineaepollenites dunrobinensis, A. microalatus, A. minimus, Cedripites minor, Eucommiidites troedssonii, etc. Some of the species are also found from the crude oil sampls taken from the Middle Jurassic reservoir of the Shengjinkou Oil-Field of the Turpan Basin. The above mentioned species of spores and pollens are widely distributed in the Lower to Middle Jurassic sediments of North America, Europe, Australia and China. They have also been found from the Lower to Middle Jurassic sediments of the Turpan Basin. Judging from the spores and pollen in petroleum, it may be concluded that the Lower Jurassic Badaowan-Sangonhe Formation and the Middle Jurassic Xishanyao-Toudenhe Formation should contain the favorable petroleum source rocks in the basin. As to petroleum migration mechanism, it is considered that petroleum must have migrated for comparatively short distances to accumulate into petroleum pools in this region. 相似文献
19.
水稻是我国主要粮食作物,每年都会因虫害造成大量的经济损失,为了挽回害虫造成的损失,必须对害虫进行防治。田间节肢动物群落调查是评价害虫防治效果的重要依据,取样方式对节肢动物群落调查的准确性具有重要的影响。另外,对转基因作物对稻田生物多样性安全性进行评价时,取样方式对多样性评价的准确性也具有重要的影响。本文采用吸虫器法、盆拍法和马氏网诱集法3种取样方式进行稻田节肢动物调查,并评估不同取样方式的采集效率。得到的结果有:1.采集到的节肢动物物种数:马氏网诱集法吸虫器法盆拍法;2.采集的节肢动物数量:盆拍法吸虫器法马氏网诱集法;3.吸虫器取样法在调查叶蝉科、秆蝇科、茧蜂科、姬蜂科、金小蜂科、缘腹细蜂科、蕈蚋科时,取样效率较高;4.盆拍取样法在调查叶蝉科、瘿蚊科、微蛛亚科、跳蛛科、狼蛛科、猫蛛科、弹尾虫目、飞虱科时,取样效率较高;5.马氏网诱集法在调查缟蝇科和毛蠓科时取样效率较高。马氏网诱集法善于采集具有飞行能力的节肢动物;吸虫器法对不同习性的节肢动物采集效果均较高;盆拍法适合采集活动于水稻基部的节肢动物。 相似文献
20.
Wang Jing-Xiang 《植物分类学报:英文版》1986,24(3):165-176
1. History of development of the forest flora Since the Cenozoic period, the number of forest tree species has steadily risen.
In the course of time, some of the archaic types slowly diminished and perished,
and new forms gradually evolved. During the palaeocene, the numher of the gymnosperms (with the exception of conifers) and ferns drastically decreased, and that of conifers, on the contrary, increased significantly, and meantime the broad-leaved tree species also appeared. During the Neocene, the angiosperms expanded rapidly and the vegetation gradually shifted towards the mixed deciduous-evergreen forest. Shortly before
the Quaternary, there was a series of world-wide climatic fluctuations, as illustrated by
progress and retreat of glaciers, cold-resistant and warm-loving (thermophilic) plants
appeared alternately. In the post-glaciation period, the zonal distribution of forest vegetation in Zhejiang Province was essentially similar to that of the present time. Excavations from Homu-tu, Yu-Yao County, reveal a luxuriant subtropical forest which
existed 7000 years ago.
2. Characteristics of the flora and vegetation
(1) Of ancient origin, with rich relic elements.
Archaic gymnosperms such as Ginkgo biloba, Amentotaxus argotaenia, Pseudotaxus
chienii, Torreya jackii, T. grandis, Taxus chinensis var. mairei, Podocarpus macrophyllus,
P. neriifolia, etc, are all found in the Cretaceous deposits. The occurrence of Ginkgo
can be traced hack to the Triassic. Most of the conifers, however, were found in the Jurassic, and they have remained to the present time as the main elements of the needleleaved forests.
Among the primitive angiosperms, Magnoliaceae is represented by 19 species of 8
genera; Fagaceae and Lauraceae are the dominant evergreen broad-leaved tree species,
the former by 6 genera and 43 species, and the latter by 10 genera and 42 species. Hamamelidaceae is represented by 10 genera and 18 species, while Ulmaceae, Tiliaceae, Elaeocarpaceae, by 21 species of 7 genera, 9 species of 2 genera and 6 species of 2 genera
respectively.
(2) Rich in species and consisting of diverse geographic elements, but dominated by the tropical ones.
Throughout Zhejiang Province, there are over 1300 taxa of woody plants (including varieties and cultivated ones) belonging to 109 families and 423 genera. Among
them, 8 families with 25 genera and about 45 species, are gymnosperms, and the rest, 101
families with 398 genera and about 1260 species and varieties, are angiosperms. The
major angiospermous families include Mognoliaceae, Fagaceae, Lauraceae, Theaceae,
Aquifoliaceae and Bambusoideae. Dominant families and genera are the tropical ones,
and next in the order, are the East Asiatic, the E. Asia-N. American, then the temperate, the cosmopolitan, endemic and other elements.
(3) Rich in endemic species, in monotypic and oligotypic genera.
The endemic species include Abies beshanzuensis, Ostrya rehderiana, Carpinus putoensis, Carpinus tientaiensis, Celtis chekiangensis, Calycanthus chinensis, Machilus minutiloba, M. chekiangensis, Semiliquidambar caudata var. cuspidata, Acer aeutum, A.
yangjuechi, A. Changhwaense, A. elegantulum, A. pauciflorum, Ilex qinyuanensis, Styrax zhejiangensis, Photinia zhejiangensis, Actinidia zhejiangensis, etc. The monotypic
and oligotypic genera are examplified by Ginkgo, Pseudotaxus, Pseudolarix, Fokienia,
Cyclocarya, Parakmeria, Pteroceltis, Sargentodoxa, Decaisnea, Aphananthe, Hemiptelea,
Zelkova, Fortunearia, Semiliquidambar, Polithyrsis, Ostrya, Heptacodium, Tapiscia,
Bretschneidera, Choerospondias, Kalopanax, Halesia, Hovenia, Emmenopterys, Eucommia, Pileostegia, Platycrater, Alniphyllum, etc. The majority of the species mentioned
above are rare and precious ones.
(4) Introduced species gaining importance
Zhejiang Province is mainly situated in the mid-subtropical zone, and from Yukuan District and the Wenzhou Prefecture southwards it belongs to the evergreen broad-leaved south subtropical forest belt. A number of south subtropical species, such as Eucalyptus spp., Casuarina spp., Acacia mearnsii, have been successfully introduced into this region. The introduction of other species, such as Cinnamomum cassia, Grevillea robusta, Michelia alba, Canarium album, Litchi chinensis, Euphoria longan, Kandelia candel, are successful in certain areas. Small plantations of introduced species from S. W. China e.e. Cinnamomum glanduliferum, C. septentrionale have been established. In
addition, Metasequoia glyptostroboides, Ulmus pumila, several exotic Pinus species, Carya illinoensis, Robinia pseudoacacia, Amorpha fruficosa, etc. are widely planted throughout Zhejiang Province. In recent years, cold-temperate species such as Chamaecyparis obtusa, Thuja standishii, Thuja occidentalis, Abies firma have been introduced and planted in the mountainous areas. The forest flora of the province is thus being further enriched.
3. Geographical analysis of the forest flora
(1) The south part of Zhejiang lies in the transitional belt between the East and
South China Floristic Regions, its east part being on the north margin of the South
China Floristic Region, and its west part on the south margin of the East China Floristic Region.
(2) The north part of the province is weakly influenced by the temperate elements, but the influence may extend to the central part of this province as the elevation
there is higher.
(3) Diverse floristic elements such as those belonging to Japan, Taiwan (China),
C. China and S. W. China regions also occur in the province, especially in its western
and eastern parts. 相似文献