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1.
Zheng Yi 《中国海洋湖沼学报》1998,16(4):369-372
Hypoglossum fujianensis sp. nov. is an epiphytic alga in the intertidal zone. Plants are light red, 0.9–2 cm high. Margin of branches gives rise
to uniseriate hair-like rhizoids, formed outward from the fusion of the second-and third-order cells. Blades are single layered
(except the midrib) and uncorticated. Tetrasporangial sori are formed on the middle part of blades. The globular tetrasporangia
are developed from lateral pericentral cells.
Project 39391800 supported by the NSFC. 相似文献
2.
Ｂｉｖａｌｖｅｓｈａｖｅｔｒａｎｓｌｕｃｅｎｔｔｈｉｎｍｅｍｂｒａｎｅｓ—ｔｈｅｇａｓｔｒｉｃｓｈｉｅｌｄｃｏｖｅｒｓｏｎｔｈｅｌｅｆｔｏｆｔｈｅｐｏｓｔｅｒｉｏｒｓｔｏｍａｃｈｗａｌｌｓ;ｔｈｅｈｅａｄｏｆｔｈｅｃｒｙｓｔａｌｌｉｎｅｓｔｙｌｅｈｏｕｓｅｄｉｎｔｈｅｓｔｙｌｅ ｓａｃｉｓｒｏｔａｔｅｄｆｏｒｗａｒｄｉｎｔｏｔｈｅｓｔｏｍａｃｈｔｏｉｍｐｉｎｇｅｔｈｅｆｏｏｄｏｎｔｈｅｇａｓｔｒｉｃｓｈｉｅｌｄ (ＺｈａｎｇａｎｄＴａｉ,1 961 ) .Ｉｔｗａｓｒｅｐｏｒｔｅｄｔｈａｔｔｈｅｇａｓｔｒｉｃ… 相似文献
3.
Morphogenesis of a population of the marine euplotid ciliate, Uronychia binucleata, which was found in Yellow Sea coastal waters next to a sewage outfall at a beach near Zhanqiao Pier, Qingdao, China, was investigated using protargol staining. The main pattern of morphogenesis is typical for the genus and can be summarized as follows: 1) the oral primordium in both proter and opisthe develops de novo in a subcortical pouch. In each daughter cell, the developing adoral zone of membranelles divides into two parts. The new membranelles formed in the proter's oral primordium will replace the leftmost five parental ones; six parental membranelles are retained by the proter; 2) the undulating membranes anlage is formed and develops independently from the oral primordium within the same subcortical pouch; 3) five primary front oventral-transverse cirral anlagen appear de novo on the cell surface; 4) the marginal cirral anlagen are formed de novo; 5) the leftmost frontal cirrus develops de novo on the cell surface; 6) two caudal cirri are formed at the posterior end of the rightmost anlage while the second primordium from the right gives rise to the third caudal cirrus. In contrast to its congeners, the anlage of the leftmost frontal cirrus is formed to the right of the undulating membranes anlage and before the formation of the latter. 相似文献
4.
We present a taxonomic study of taxa of the red algae genus Herposiphonia (Rhodophyta, Rhodomelaceae), collected from the coast of eastern Guangdong, China. We made detailed morphological studies and considered recent taxonomic criteria for species delimitation, and are making the first report of five different species on the coast of Guangdong, including a new species. The species identified were H. caespitosa Tseng, H. hollenbergii Dawson, H. pecten - veneris (Harvey) Falkenberg, H. subdisticha Okamura and H. pinnata Ding and Tan sp. nov. H. pinnata sp. nov. is characterized by bright green thalli; most parts of the feathery thalli are free of the substratum; determinate branches and indeterminate branches are arranged in a chaotic sequence; the primary axis has bare segments; the determinate branch has 9–11 periaxial cells per segment; vegetative trichoblasts are abundant; and tetrasporangia are formed on the middle of the determinate branch with 1–8 successive segments in a single rectilinear series. This paper is also the first record of sporophyte plants of H. pecten-veneris. 相似文献
5.
The early stages and capsulogenetic stages of sporogenesis of Myxobolus kwangsiensis were studied indetail by electron microscopy. M. kwangsiensis is an intrasellular myxsporen infecting the epithelial cellsof kidney tubules of young dace Labeo rohita. The M. kwangsiensis sporogenesis presents the typical featuresof myxosporea. The initial stages are multinuceate primary cells, with one primary cell typicallyenclosing one secondary cell. The secondary cells are formed directly by cytokinesis inside the primary cells. Theprimary cell participates in the formation of the secondary cell nucleus. The nuclear division of primarycell is asynchronous by amitosis. The parasitic organisms may degenerate inside the epithelial cells at anystage. The modes of sporoblast formation , the typical features of myxosporea and the cause of its degradationare discussed. 相似文献
6.
The early stages and capsulogenetic stages of sporogenesis ofMyxobolus kwangsiensis were studied in detail by electron microscopy.M. kwangsiensis is an intracellular myxosporean infecting the epithelial cells of kidney tubules of young daceLabeo rohita. TheM. kwangsiensis sporogensis presents the typical features of myxosporea. The initial stages are multinucleate primary cells, with one primary
cell typically enclosing one secondary cell. The secondary cells are formed directly by cytokinesis inside the primary cells.
The primary cell participates in the formation of the secondary cell nucleus. The nuclear division of primary cell is asynchronous
by amitosis. The parasitic organisms may degenerate inside the epithelial cells at any stage. The modes of sporoblast formation,
the typical features of myxosporea and the cause of its degradation are discussed.
This research was supported by the NSFC. (No. 39070675) 相似文献
7.
It had been demonstrated that individual cells or protoplasts isolated from Porphyra thallus by enzyme could develop into normal leafy thalli in the same way as monospores, and that isolated cells develop in different way in liquid and on semi solid media. The authors observed the ultrastructure of isolated vegetative cells cultured on semi solid media and compared them with those of monospores and isolated cells cultured in liquid media. The results showed that subcellular structures were quite different among cells in different conditions. In their development, isolated cells on semi solid media did not show the characteristic subcellular feature of monospore formation, such as production of fibrous vesicles. Callus like cells formed on semi solid media underwent a distinctive modification in cellular organization. They developed characteristic cell inclusions and a special 2 layer cell covering. Golgi bodies, ER, starch grains, mitochondria. Vacuoles were not commonly found in them. 相似文献
8.
The gastric shield and underlying stomach epithelium of Chlymas ffarreri were examined at the light and ultrastructural levels.The results showed that the gastric shield consisted of two different size lobes joined together by a narrow middle piece,the thicker lobe was shaped like a funnel,but unclosed at the lateral side;the other lobe was irregularly triangular-shaped.The transverse section of the thicker lobe was obviously laminated and gradually decreased in thickness from the peak to the margins of the shield.The underlying epithelium bore numerous about 3μm diameter spherical processes formed by the apical plasmalemma of the epithelial cells becoming blunt pseudopodia.Microvilli and some interspersed cilia were present in the areas among the spherical processes regions where only microvilli existed.Rough endoplasmic reticulum,Golgi apparatus,different-sized electron-dense secretory granules and electron-lucent vacuoles as well las abundant mitochondria were present in the underlying epithelial cells.Fused droplets of the secretion from the underlying epithelial cells formed the gastric shield. 相似文献
9.
Effect of temperature and irradiance on the growth and reproduction of Enteromorpha prolifera J. Ag. （Chlorophycophyta, Chlorophyceae） 总被引：1，自引：0，他引：1
Effect of temperature and irradiance on growth and reproduction of Enteromorpha prolifera that bloomed offshore along the Qingdao coast in summer 2008, was studied. It was showed that E. prolifera propagated mainly asexually with specific growth rate (SGR) of 10.47 at 25°C/40 μmol m-2s-1. Under this condition, gametes with two flagellate formed and released in 5 days. At the beginning of the development, the unicell gamete divided into two cells with heteropolarity, and then the apical cell developed into thalli primordial cells, whereas the basal cell developed into rhizoid primordial cells. In 8-day culture, the monoplast gamete developed into juvenile germling of 240 μm in length. Unreleased gametes can develop directly within the alga body. E. prolifera could either reproduce through lateral branching or fragmenting except apomixis revealed by Microscopic observation. On aged tissue of E. prolifera, although the degraded pigments partially remained in faded algal filaments, numerous vegetative ceils could still divide actively in the algal tissues. 相似文献
10.
本文仅对广西灌阳县古怪冲锡矿床的岩石、矿石中的石英流体包裹体特征研究,探索了成岩、成矿的物理化学条件。认为成矿流体源于花岗岩浆,含锡云英岩是残余岩浆期的产物,伟晶岩与含锡石英脉具岩浆期后热液属性。根据石英包裹体的各种数据,可确定成矿物质来源,划分成岩、成矿阶段,以及矿床形成的物理化学条件。 相似文献
11.
新疆包古图斑岩铜矿中性复式岩体的同化混染作用 总被引：4，自引：0，他引：4
包古图斑岩铜矿位于新疆西准噶尔地区东南部,是一大中型斑岩铜矿床,赋存于包古图中性复式岩体中。包古图中性复式岩体是由早期闪长岩株和晚期闪长玢岩脉组成,以前者为主;该岩体侵位于下石炭统包古图组酸性火山-沉积岩中。对包古图闪长岩株及其围岩进行岩相学、岩石主量和微量元素地球化学及Sm-Nd同位素地球化学等方面进行研究。结果表明:闪长岩株由(石英)闪长岩(含少量辉长岩)、似斑状(石英)闪长岩及少量斜长花岗斑岩组成;其岩石是由偏基性的中性岩浆结晶(分异)作用及岩浆与酸性围岩同化混染作用形成的。同化混染作用的程度不同,则形成不同的岩石:①岩浆直接结晶作用形成辉长岩;②岩浆结晶(分异)作用和少量同化混染作用形成(石英)闪长岩和似斑状(石英)闪长岩;③强烈的同化混染作用形成斜长花岗斑岩,斑岩基质主要由混入岩浆的围岩细碎屑经重结晶作用形成,斑晶是晚于基质结晶的"晚生斑晶"。总之,岩浆与围岩的同化混染作用是包古图岩体的重要成岩作用。 相似文献
12.
Yang Gangbin 《地球科学与环境学报》1997,(3)
延边地区北部大面积出露中生界（Ｊ３）火山岩系，为正常的钙碱性系列，由玄武岩－安山岩－石英安山岩组成，以富含ＡＳ、Ａｇ、Ｓｂ、ＡＳ、Ｂｉ为特征。其中的金矿床可分为两类即蚀变岩型高温热液矿床和浅成中低温热液矿床。同位素资料表明，其成矿热液主要来自火山岩浆。 相似文献
13.
Quaternary glacio-erosional landforms in Laoshan Mountain and their constraints on the origin of Jiaozhou Bay, Qingdao, east of China 总被引：2，自引：0，他引：2
A field investigation on Quaternary glacial landforms in Laoshan Mountain has discovered many glacial potholes, scouring grooves on top of granite ridges, and large boulders. These erosional landforms were formed by the meltwater from the overlying ice cap, suggesting that there was at least an ice cap covering Laoshan Mountain and the surrounding areas or even a continental ice sheet over the vast area of Shandong Province in the Late Pleistocene. The ice sheet was obstructed by the Laoshan Mountain, Dazhu Mountain and Xiaozhu Mountain in the coastal areas as it moved toward the Yellow Sea. The ice flows eroded the bedrock and carved the weak intersection of the fault systems in the NE and NW directions into a deep channel, which gradually formed a fjord in the area of the Jiaozhou Bay basin by 20.00 ka BP. The seawater gradually invaded the fjord from the beginning of the Holocene (11.00 ka BP) and Jiaozhou Bay was eventually formed. Similar fjords are easily found along the east of China and they share a similar origin because of the Quaternary glaciation in the region. 相似文献
14.
Eucheuma gelatinae (Esper) J. Agardh has vegetative and reproductive features distinguishing it from other species ofEucheuma. The occurrence of reproductive nemathecia containing carpogonial branches, auxiliary cells and post-fertilization stages
including gonimoblast and pericarp initiation, fusion cell formation stages and carposporophyte development are described
and ilustrated for the first time for this species.
Contribution No. 2380 of the Institute of Oceanology, Chinese Academy of Sciences. 相似文献
15.
The Dayizishan scoria cone and Jinlongdingzi scoria cone in the Longgang volcanic swarm, northeastern China are comprised of basaltic fallout tephra that derived from sub - Plinian eruptions. The airborn tephra formed a scoria cone and tephra sheets in geomorphological character. The fallout tephra deposits consist of basaltic scoria, bomb, ultramafic xenolith and lithic fragments. The tephra deposits in the tephra sheets developed plane parallel bedding and graded bedding. The size parameters of tephra changed with distance away from source and the lapse of time regularly.The Dalongwan tuff ring and Longquanlongwan tuff ring in Longgang volcanic swarm are comprised of base surge deposits, formed by phreatomagmatic explosions. The base surge deposits are composed of basaltic lapilli, pisolites and tuff.The sedimentary structure, for instance, dunelike structure, chute and pool structure, U - shaped channel and cross bedding, massive beds and sandwave beds etc. are recognized. 相似文献
16.
Eucheuma gelatinae (esper)J.Agardh has vegetative and reproductive features distinguishing it fromother species of Eucheuma.The occurrence of reproductive nemathecia containing carpogonial branches,auxiliary cells and post-fertilization stages including gonimoblast and pericarp initiation,fusion cell foram-tion stages and carposporophyte development are described and ilustrated for the first time for this species. 相似文献
17.
Effect of temperature and irradiance on growth and reproduction of Enteromorpha prolifera that bloomed offshore along the Qingdao coast in summer 2008, was studied. It was showed that E. prolifera propagated mainly asexually with specific growth rate （SGR） of 10.47 at 25℃/40 μmol m^-2s^-1. Under this condition, gametes with two flagellate formed and released in 5 days. At the beginning of the development, the unicell gamete divided into two cells with heteropolarity, and then the apical cell developed into thalli primordial cells, whereas the basal cell developed into rhizoid primordial cells. In 8-day culture, the monoplast gamete developed into juvenile germling of 240 μm in length. Unreleased gametes can develop directly within the alga body. E. prolifera could either reproduce through lateral branching or fragmenting except apomixis revealed by Microscopic observation. On aged tissue of E. prolifera, although the degraded pigments partially remained in faded algal filaments, numerous vegetative cells could still divide actively in the algal tissues. 相似文献
18.
ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｓｉｎｇｌｅｃｅｌｌｓａｎｄｐｒｏｔｏｐｌａｓｔｓｏｆＰｏｒｐｈｙｒａｇａｍｅｔｏｐｈｙｔｅｂｌａｄｅｓｃｏｕｌｄｄｅｖｅｌｏｐｉｎｔｏｐｌａｎｔｌｅｔｓｄｉ ｒｅｃｔｌｙｏｒｉｎｔｏｃａｌｌｕｓ ｌｉｋｅｃｅｌｌｓ (ＺｈａｏａｎｄＺｈａｎｇ ,1 981 ;Ｐｏｌｎｅ Ｆｕｌｌｅｒｅｔａｌ.,1 984 ;Ｃｈｅｎ ,1 989;ＷａｎｇａｎｄＹａｎ ,1 990 ;Ｇａｌｌｅｔａｌ.,1 993;Ｃｈｅｎ ,1 997;ＭｅｉａｎｄＦｅｉ,2 0 0 1 ) ,ａｎｄｔｈｅｉｒｇｒｏｗｔｈａｎｄｄｅｖｅｌｏｐｍｅｎｔｕｎｄｅｒ… 相似文献
19.
Donald A. FRIEND 《山地科学学报》2005,2(3):181-192
Introduction Studies on microfabric and macrofabric are common, spanning from the sedimentology of fine grained rock to fabric analyses of glacial and periglacial deposits. These studies generally focus on one deposit that is all the same age. This study is unique in that identical measures of fabric were taken on a series of like deposits on the steep slopes (~25° to ~35°) of rhyolite domes in eastern California (Figures 1 and 2) whose maximum possible age stretches over a one-million-year… 相似文献
20.
Compared to burn interiors, edges exhibit distinct biotic and abiotic conditions that include microclimate, wind speed, sunlight levels, soil composition, moisture content, nutrient availability, population density, and species diversity. This study characterized the landscapes in which burned forest edges formed in Samcheok, Korea. Over the study area, 500-m2 grid cells were generated to capture landscape characteristics. Grid cells intersecting burn boundary lines were designated as edge, while cells without these lines were classified as the interior of burned areas. Topographic variables including slope, elevation, topographic wetness index, solar radiation index, and proportions of fuel and land use types within grid cells were computed in a geographical information system （GIS）. Correlation analysis with modified t-test and regression tree analysis were performed to explore the influences of landscape variables on edge formation with avoiding spatial autocorrelation problems. The results indicated that edges formed at low elevations with mild slopes, high topographic wetness, and low solar radiation. Edges were unlikely to form in areas dominated by Japanese red pines at low elevations. Moreover, heterogeneous land use/cover types contributed significantly to edge formation. Different forest management strategies for different landscape conditions can be more effective for enhancing resilience of forests to fire. Reducing susceptible fuel types might be effective at low elevations, while enhancing forest heterogeneity might be more effective at high elevations. 相似文献