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新型弹性盖板针布的发展 被引量:1
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作者 陈玉峰 陆荣生 《纺织器材》 2021年第3期14-18,共5页
为合理应用新型盖板针布、提高对纤维的梳理效果,介绍其发展趋势,对比MCH(TP)缎纹渐密型、MCB匀密直线斜纹型、HX稀密直缎纹结合型、MCC横密斜线缎纹型、BNT(MCBH)斜纹弧线渐密型及MCZ型新型弹性盖板针布的优点,分析植针排列、针尖和截... 为合理应用新型盖板针布、提高对纤维的梳理效果,介绍其发展趋势,对比MCH(TP)缎纹渐密型、MCB匀密直线斜纹型、HX稀密直缎纹结合型、MCC横密斜线缎纹型、BNT(MCBH)斜纹弧线渐密型及MCZ型新型弹性盖板针布的优点,分析植针排列、针尖和截面形状及植角δ、总高h 1、梳针几何尺寸与热处理、针密λ、底布问题及改进措施,从6方面探讨回转盖板技术创新应用。指出:新型弹性盖板针布产品质量显著提高,且免维护、方便维修、使用周期长,促进智能化和自动化改造;新型弹性盖板针布的发展趋势是直通道、变前角α、横向针密λ大、总高h 1小、适用广,才能符合高速高产高质高效、提高棉结杂质清除率、长使用周期的梳理要求。 展开更多
关键词 回转盖板 弹性盖板针布 梳理 短绒率 棉结 植针方式 总高h 1 植角δ 针密λ
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On Some Dispersed Cordaitean Cuticles from Cathaysian Flora in the Permian of China and Their Significance 被引量:1
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作者 李生盛 王士俊 贝月敏 《Acta Botanica Sinica》 CSCD 2003年第5期517-522,共6页
Although the research on Cordaites of the Cathaysian Flora in China started early in 1883, the study of the cordaitean cuticles began late in 1991. Up to now, four types of cordaitean cuticles in situ and three types ... Although the research on Cordaites of the Cathaysian Flora in China started early in 1883, the study of the cordaitean cuticles began late in 1991. Up to now, four types of cordaitean cuticles in situ and three types of dispersed ones have been reported from the Cathaysian Flora in China. However compared with the Euramerican Flora, the research work on cordaitean cuticles from the Cathaysian Flora in China is much more insufficient. In this paper, three kinds of dispersed cordaitean cuticles are described in detail from the Permian coal-bearing strata in China. Among these cuticles two kinds are collected from the roof shale of Coal Seam No. A(1) in Shanxi Formation (Lower Permian) in Xinzhuangzhi Coal Mine of Huainan, Anhui Province, southern border of North China Subprovince of the Cathaysian Flora in China. The third one was collected from Coal Seam No. 11 in the top of Longtan Formation (lower Upper Permian) in Dahebian Coal Mine of Shuicheng Mining District, Guizhou Province, South China Subprovince of the Cathaysian Flora in China. Comparison of these three kinds of cordaitean cuticles with the known ones from the Cathaysian Flora in China and from the Euramerican Flora is made. The authors consider that they are all new types of cordaitean cuticles. The significance they bear on palaeobotany is discussed. 展开更多
关键词 China Cathaysian Flora PERMIAN cordaitean plants cuticle new types
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A Biosystematic Study on Asplenium sarelii Complex 被引量:5
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作者 王中仁 王可青 +1 位作者 张方 侯鑫 《Acta Botanica Sinica》 CSCD 2003年第1期1-14,共14页
The series Variantia Ching et S. H. Wu mainly occur in China and its members are highly variable in morphology. The denomination on this group of Asplenium is very confused in the herbaria. We hop e by means of a bios... The series Variantia Ching et S. H. Wu mainly occur in China and its members are highly variable in morphology. The denomination on this group of Asplenium is very confused in the herbaria. We hop e by means of a biosystematic study to find out their genetic relationships in the reticulate evolution, and to raise a suggestion on their taxonomic treatment. Evidence from cytology, allozyme, morphology, and palynology shows that three ancestor diploids have formed Asplenium sarelii complex comprising 13 members. A. sarelii Hook. should be typified as a diploid. The so-called tetraploid 'A. sarelii' before is an allotetraploid that comes from the doubled hybrid between diploid A. sarelii and A. tenuicaule Hayata, which should be treated as a new species A. wudangense Z. R. Wang et X. Hou. A. pekinense Hance is an autotetraploid that comes from the doubled diploid ancestor A. sarelii. A. lushanense C. Chr., a diploid species and the only ancestor of A. yunnariense group, should not been sunk as a synonym of tetraploid A. yunnariense Franch. Most probably, A. varians Wall. ex Hook. et Grev. is an autotetraploid of A. tenuicaule Hayata. Three new natural tetraploid hybrids and their origins have been found out: they are A. x longmenense ( = A. pekinense x varians), A. x jingyunense ( = A. pekinense x yunnanense) and A. x kidoi ( = A. pekinense x wudangense). Three other new natural triploid hybrids have been found and their origins have been inferred: they are A. X huawuense ( = A. sarelii X wudangense), A. x luyunense ( = A. lushanense x yunnanense) and A. x teniuvaians ( = A. tenuicaule x varians). The method of allozyme comparion combined with cytological observation is employed to reveal the complicated relationships among the members of Asplenium sarelii complex in reticulate evolution and proved to be a highly effective tool to investigate the origin of polyploid and hybrid. 展开更多
关键词 PTERIDOPHYTES Asplenium L. BIOSYSTEMATICS reticulate evolution CYTOLOGY ALLOZYME China
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Spatial and environmental effects on plant communities in the Yellow River Delta, Eastern China 被引量:8
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作者 宋创业 刘高焕 刘庆生 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第2期117-122,I0002,共7页
Types and structure of plant communities in the Yellow River Delta were investigated by using detrended canonical correspondence analyses (DCCAs) and a two-way indicator species analysis (TWINSPAN). The distributi... Types and structure of plant communities in the Yellow River Delta were investigated by using detrended canonical correspondence analyses (DCCAs) and a two-way indicator species analysis (TWINSPAN). The distribution pattern and influential factors of the plant communities were also analyzed by testing elevation, slope, soil characteristics, longitude and latitude of 134 vegetation samples collected by representative plot sampling methods. Results showed that all the 134 vegetation samples could be divided into seven vegetation groups, separately dominated by Robinia pseucdoacacia, Imperata cylindrical, Miscanthus saccharifleus, Suaeda salsa, Aeluropus sinensis, Phragmites australis and Tamarix chinensis. The vegetation distribution pattern was mainly related to elevation, ground water depth and soil characteristics such as salinity and soluble potassium. Among the factors affecting distribution pattern of the plant communities, the species matrix explained by non-spatial environmental variation accounts for 45.2% of total variation. Spatial variation and spatial-structured environmental variation explain 11.8%, and 2.2%, respectively. Remained 40.8% of undetermined variation is attributed to biological and stochastic factors. 展开更多
关键词 detrended canonical correspondence analyses environmental factors plant communities spatial factors Yellow River Delta two-way indicator species analysis
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浅析梳棉机弹性盖板针布充塞挂花起因 被引量:5
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作者 刘小云 《纺织器材》 2011年第2期11-14,共4页
为提高梳棉机弹性盖板针布对纤维的分梳、除杂、均匀、混合等梳理效果,解析了弹性盖板针布分梳纤维的过程;通过建立理论模型,进一步分析了弹性盖板针布与锡林针布之间分梳纤维时的力学状态,归纳、建立数学关系式μ=tanα;联系生产实际,... 为提高梳棉机弹性盖板针布对纤维的分梳、除杂、均匀、混合等梳理效果,解析了弹性盖板针布分梳纤维的过程;通过建立理论模型,进一步分析了弹性盖板针布与锡林针布之间分梳纤维时的力学状态,归纳、建立数学关系式μ=tanα;联系生产实际,解析弹性盖板针布充塞挂花的起因。指出:弹性盖板针布充塞挂花的根源在于对针布与纤维之间的摩擦因数μ及梳针角的控制;针布制造厂应控制生产中的影响因素,棉纺厂应提供良好的梳理状态及连续高效的物料平衡条件,以避免或消除弹性盖板针布梳针间充塞或留挂纤维。 展开更多
关键词 梳棉机 弹性盖板针布 充塞 挂花 分梳过程 力学状态 梳针 前角 摩擦因数 底布 植角
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梳棉机弹性盖板针布嵌杂原因及控制 被引量:4
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作者 陈玉峰 《纺织器材》 2015年第4期27-30,34,共5页
为了解决梳棉机弹性盖板针布嵌杂问题,介绍了弹性盖板针布嵌杂的分类,分析其原因并提出相应的控制措施,并对高速高产梳棉机针布嵌杂的控制进行了探讨。指出:弹性盖板针布嵌杂是因为针布自身缺陷、原料含糖含杂大、针布选型不当、流程排... 为了解决梳棉机弹性盖板针布嵌杂问题,介绍了弹性盖板针布嵌杂的分类,分析其原因并提出相应的控制措施,并对高速高产梳棉机针布嵌杂的控制进行了探讨。指出:弹性盖板针布嵌杂是因为针布自身缺陷、原料含糖含杂大、针布选型不当、流程排杂工艺配合及管理不当等因素影响所致;生产时,应加强针布选型、设备管理和维护,降低弹性针布总高,增大植针角度和针密,改进底布结构和原料钢丝截面,就能有效控制弹性盖板针布嵌杂。 展开更多
关键词 梳棉机 弹性盖板针布 嵌杂 分梳 梳针 植角 针密 底布
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起毛针布与起毛 被引量:3
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作者 陈翔鸿 《纺织器材》 2006年第3期38-43,共6页
分析了起毛针布钢丝、底布、针形、织物与起毛速度对起毛效果的影响,简述了不同织物的起毛要求和对起毛针布的选择。
关键词 起毛针布 纤维 织物 底布 植角 前角 起毛速度
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Study on Shoot Tip Culture of Illciaceae Ornamental Plants
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作者 方向明 赵后斌 +2 位作者 刘文倩 郑必平 谈建中 《Agricultural Science & Technology》 CAS 2012年第4期735-738,759,共5页
[Objective] This study aimed to establish a technology system for tissue culture and rapid propagation of Illciaceae ornamental plants. [Method] Effects of medium components and anti-browning agents on the survival an... [Objective] This study aimed to establish a technology system for tissue culture and rapid propagation of Illciaceae ornamental plants. [Method] Effects of medium components and anti-browning agents on the survival and growth of shoot tips were investigated by using apical buds of IItciaceae plant Haierlian as experiment material and MS as basic medium. [Result] The results showed that apical buds at the early germination period in spring were the most suitable explants for tissue culture of IIIciaceae plant Haierlian. Sterilization with 0.1% HgCI2 for 6 min achieved the best effect, while conventional surface-sterilization with ethanol would affect the survival of explants. The optimal medium for primary culture was MS-D (with modifications in major elements and organic components) + anti-browning agents (equa~ volume) + 2.0 mg/L of 6-BA + 0.5 mg/L of NAA. The optimal subculture medi- um was MS-F (with modifications in inorganic and organic components) + anti-brown- ing agents (equal volume) + 2.0 mg/L of 6-BA + 0.1 mg/L of NAA. [Conclusion] This study laid the foundation for establishment of tissue culture and rapid propagation technology system for Haierlian. 展开更多
关键词 Illciaceae plant Haieflian Shoot tip culture Sterile system Tissue browning
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LAZY1 controls rice shoot gravitropism through regulating polar auxin transport 被引量:96
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作者 Peijin Li Yonghong Wang +6 位作者 Qian Qian Zhiming Fu Mei Wang Dali Zeng Baohua Li Xiujie Wang Jiayang Li 《Cell Research》 SCIE CAS CSCD 2007年第5期402-410,共9页
Tiller angle of rice (Oryza sativa L.) is an important agronomic trait that contributes to grain production, and has long attracted attentions of breeders for achieving ideal plant architecture to improve grain yiel... Tiller angle of rice (Oryza sativa L.) is an important agronomic trait that contributes to grain production, and has long attracted attentions of breeders for achieving ideal plant architecture to improve grain yield. Although enormous efforts have been made over the past decades to study mutants with extremely spreading or compact tillers, the molecular mechanism underlying the control of tiller angle of cereal crops remains unknown. Here we report the cloning of the LAZY1 (LA1) gene that regulates shoot gravitropism by which the rice tiller angle is controlled. We show that LA1, a novel grass-specific gene, is temporally and spatially expressed, and plays a negative role in polar auxin transport (PAT). Loss-of-function of LA1 enhances PAT greatly and thus alters the endogenous IAA distribution in shoots, leading to the reduced gravitropism, and therefore the tiller-spreading phenotype of rice plants. 展开更多
关键词 LAZY1 GRAVITROPISM auxin transport tiller angle plant architecture Oryza sativa L.
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Plant community succession in modern Yellow River Delta, China 被引量:8
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作者 ZHANG Gao-sheng WANG Ren-qing SONG Bai-min 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2007年第8期540-548,共9页
Data were collected in different successional stages using a simultaneous sampling method and analyzed through quantitative classification method. Three large groups and 12 classes were made to represent the community... Data were collected in different successional stages using a simultaneous sampling method and analyzed through quantitative classification method. Three large groups and 12 classes were made to represent the community patterns of three succession stages and 12 succession communities. The succession series of plant community in the study area was as follows: saline bare land→community Suaeda salsa→community Tamarix chinensis→grassland. Succession degree and succession process of 12 succession communities were calculated. Most of these communities were in the lower succession stage, however, community Phragmites communis+Glycine soja and community Imperata cylindrica+G. soja were close to the succession stage of grassland climax. Five species diversity indices were used to study the changes in species richness, species evenness and diversity during succession of community. Heterogeneity index and richness index increased gradually during the community succession process, but species evenness tended to decrease with succession development. The relation between succession and environment was studied by ordination technique, and the results showed that the soil salt content was an important factor to halarch succession of the modern Yellow River Delta. It affected community structure, species composition and succession process. 展开更多
关键词 Community succession DCA and TWINSPAN analysis Yellow River Delta
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Corneal relaxing incision combined with phacoemulsification and IOL implantation 被引量:1
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作者 沈晔 童剑萍 李毓敏 《Journal of Zhejiang University Science》 CSCD 2004年第8期985-988,共4页
Objective: To analyze the effectiveness and safety of corneal relaxing incisions (CRI) in correcting keratometric astigmatism during cataract surgery. Methods: A prospective study of two groups: control group and trea... Objective: To analyze the effectiveness and safety of corneal relaxing incisions (CRI) in correcting keratometric astigmatism during cataract surgery. Methods: A prospective study of two groups: control group and treatment group. A treatment group included 25 eyes of 25 patients who had combined clear corneal phacoemulsification, IOL implantation and CRI. A control group included 25 eyes of 25 patients who had clear corneal phacoemulsification and IOL implantation.Postoperative keratometric astigmatism was measured at 1 week, 1 month, 3 months and 6 months. Results: CRI signifi-cantly decreased keratometric astigmatism in patients with preexisting astigmatism compared with astigmatic changes in the control group. In eyes with CRI, the mean keratometric astigmatism was 0.29±0.17 D(range 0 to 0.5 D) at 1 week, 0.41±0.21 D (range 0 to 0.82 D) at 1 month, respectively reduced by 2.42 D and 2.30 D at 1 week and 1 month postoperatively (P=0.000, P=0.000), and postoperative astigmatism was stable until 6 months follow-up. The keratometric astigmatism of all patients decreased to less than 1.00 D postoperatively. Conclusions: CRI is a practical, simple, safe and effective method to reduce preexisting astigmatism during cataract surgery. A modified nomogram is proposed. The long-term effect of CRI should be investigated. 展开更多
关键词 ASTIGMATISM Corneal relaxing incision CATARACT
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Application of Remote Sensing Detection and GIS in Analysis of Vegetation Pattem Dynamics in the Yellow River Delta
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作者 Song Chuangye Liu Gaohuan 《Chinese Journal of Population,Resources and Environment》 北大核心 2008年第2期62-69,共8页
Regional vegetation pattern dynamics has a great impact on ecosystem and climate change. Remote sensing data and geographical information system (GIS) analysis were widely used in the detection of vegetation pattern... Regional vegetation pattern dynamics has a great impact on ecosystem and climate change. Remote sensing data and geographical information system (GIS) analysis were widely used in the detection of vegetation pattern dynamics. In this study, the Yellow River Delta was selected as the study area. By using 1986, 1993, 1996, 1999 and 2005 remote sensing data as basic information resource, with the support of GIS, a wetland vegetation spatial information dataset was built up. Through selecting the landscape metrics such as class area (CA), class percent of landscape (PL), number of patch (NP), largest patch index (LPI) and mean patch size (MPS) etc., the dynamics of vcgetation pattern was analyzed. The result showed that the change of vegetation pattern is significant from 1986 to 2005. From 1986-1999, the area of the vegetation, the percent of vegetation, LPI and MPS decreased, the NP increased, the vegetation pattern tends to be fragmental. The decrease in vegetation area may well be explained by the fact of the nature environment evolution (Climate change and decrease in Yellow River runoff) and the increase in the population in the Yellow River Delta. However, from 1999 2005, the area of the vegetation, the percent of vegetation, LPI and MPS increased, while the NP decreased. This trend of restoration may be due to the implementation of water resources regulation for the Yellow River Delta since 1999. 展开更多
关键词 remote sensing geographical information system (GIS) landscape metrics Yellow River Delta vegetation pattern
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EFFECT OF HUMAN AMNIOTIC MEMBRANE ON CORNEAL EPITHELIUM AND YAC-1 CELL
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作者 叶纹 沈玺 钟一声 《Journal of Shanghai Second Medical University(Foreign Language Edition)》 2003年第1期65-70,共6页
Objective To study the effect of the amniotic membrane on enhancing the proliferation ofcorneal epithelia and YAC-1 cell. Methods After the primary culture of the rabbit's corneal epithelia and YAC-1 cells, they w... Objective To study the effect of the amniotic membrane on enhancing the proliferation ofcorneal epithelia and YAC-1 cell. Methods After the primary culture of the rabbit's corneal epithelia and YAC-1 cells, they were seeded on the upper surface or stromal matrix side of amniotic membrane respectively. The proliferation results were observed by MTT test. Results The amniotic membrane was found significantly enhancing the proliferation of corneal epithelia on the d1 ,d3 , and d5 after culture. The proliferation rate was 28.93% ,23.32% ,23.41 % (P<0 .05) respectively, but the d7 proliferation rate was 20.72% (P> 0.05). On the dl , d3 , d7 after culture , the YAC-1 cells proliferation rate was 34 .87% ,36 .28% ,33 .86% (P< 0.01) respectively. Conclusion Our results demonstrated that the amniotic membrane could enhance the proliferation of both corneal epithelia and YAC-1 cells significantly. Although amniotic membrane has been suggested as an ideal material for reconstruction of ocular surface, special attention should be paid during amniotic membrane transplantation for treating ocular surface lesion resulted from epibulbar tumors. 展开更多
关键词 amniotic membrane corneal epithelium YAC-1 proliferation
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Pollen and Phytolith Analyses of Ancient Paddy Fields at Chuodun Site, the Yangtze River Delta 被引量:8
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作者 LI Chun-Hai ZHANG Gang-Ya +6 位作者 YANG Lin-Zhang LIN Xian-Gui HU Zheng-Yi DONG Yuan-Hua CAO Zhi-Hong ZHENG Yun-Fei DING Jin-Long 《Pedosphere》 SCIE CAS CSCD 2007年第2期209-218,共10页
A number of paddy fields pertaining to the Majiabang Cultures (5500-3800 years BC) were discovered during the archaeological excavations that were carried out since 1998 at the Chuodun site in the Yangtze River Delta.... A number of paddy fields pertaining to the Majiabang Cultures (5500-3800 years BC) were discovered during the archaeological excavations that were carried out since 1998 at the Chuodun site in the Yangtze River Delta. The pollen and phytolith analyses of two soil profiles from the northeastern part of this site were carried out to trace the agricultural practices of the Neolithic period. The phytolith results showed that rice domestication in the Yangtze River Delta could be traced back to as early as the Majiabang Culture. The pollen assemblage also revealed low levels of aquatic species, similar to that in modern paddy fields. This finding suggested that humans might have removed weeds for rice cultivation during the Neolithic period. Thus, pollen analysis in association with phytolith analysis was a promising method for identifying ancient paddy fields. 展开更多
关键词 ancient paddy fields Neolithic period pollen analysis phytolith analysis Yangtze River Delta
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Rice leaf inclination2, a VIN3-1ike protein, regulates leaf angle through modulating cell division of the collar 被引量:36
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作者 Shu-Qing Zhao Jiang Hu +2 位作者 Long-Biao Guo Qian Qian Hong-Wei Xue 《Cell Research》 SCIE CAS CSCD 2010年第8期935-947,共13页
As an important agronomic trait, inclination of leaves is crucial Ior crop architecture and grain yields. 10 understand the molecular mechanism controlling rice leaf angles, one rice leaf inclination2 (1c2, three all... As an important agronomic trait, inclination of leaves is crucial Ior crop architecture and grain yields. 10 understand the molecular mechanism controlling rice leaf angles, one rice leaf inclination2 (1c2, three alleles) mutant was identified and functionally characterized. Compared to wild-type plants, lc2 mutants have enlarged leaf angles due to increased cell division in the adaxial epidermis of lamina joint. The LC2 gene was isolated through positional cloning, and encodes a vernalization insensitive 3-like protein. Complementary expression of LC2 reversed the enlarged leaf angles of lc2 plants, confirming its role in controlling leaf inclination. LC2 is mainly expressed in the lamina joint during leaf development, and particularly, is induced by the phytohormones abscisic acid, gibberellic acid, auxin, and brassinosteroids. LC2 is localized in the nucleus and defects of LC2 result in altered expression of cell division and hormone-responsive genes, indicating an important role of LC2 in regulating leaf inclination and mediating hormone effects. 展开更多
关键词 leaf inclination RICE VIN3-1ike protein cell division LC2
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Botanical Study on Early Cretaceous Coal-Bearing Strata in Northeast China and Inner Mongolia, China
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作者 梅美棠 《Journal of China University of Mining and Technology》 2002年第1期12-14,共3页
Study on the fossil plants and the palynological assemblage is the basic botanical research on the coal bearing strata. The practice indicate that comprehensive data from the study on the fusinized wood fossil, the ph... Study on the fossil plants and the palynological assemblage is the basic botanical research on the coal bearing strata. The practice indicate that comprehensive data from the study on the fusinized wood fossil, the phyterals and the analysis of dispersed cuticles will effectively improve the level of the study on the coal bearing strata as a whole. 展开更多
关键词 fossil plants palynological assemblage fusinized wood fossil phyterals dispersed cuticles
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Contribution to the Study of Aquatic Macrophytes from Musura Bay (Danube Delta, Romania)
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作者 Daciana Sava Manuela Diana Samargiu Gabriela Mihaela Paraschiv 《Journal of Environmental Science and Engineering(A)》 2015年第12期623-627,共5页
Danube Delta--a unique, young and continuing growing region, is a favorable place for developing a unique flora and fauna with many rare and protected species in Europe. Even though the terrestrial environment is pres... Danube Delta--a unique, young and continuing growing region, is a favorable place for developing a unique flora and fauna with many rare and protected species in Europe. Even though the terrestrial environment is present in the area, the predominance of the aquatic environment led to the existence of a particular macrophytic flora. At the contact point of the sea-water and freshwater, physical, chemical and biological processes occur. As a consequence, researchers consider these coastal waters special ecosystem, in which Musura bay is the most representative one. The purpose of this paper is to contribute to the study of aquatic submerged and floating macrophytes. The present study took place over two years (2013-2014). In each year, a number of expeditions were made in different seasons in order to observe the diverse flora and flora associations. This due to seasonal variation in water quality, and might be a significantly seasonality of the vegetation also. The importance of the studies regarding flora of the Danube Delta, consist in the fact that the plants in this area are of social and economical importance, but also very important for environmental conservation. 展开更多
关键词 Danube Delta Musura bay aquatic macrophytes.
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Lipovtsy flora of Razdolnaya( Suifun) River Basin,Primorye region,Russia
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作者 E.B.Volynets E.V.Bugdaeva +1 位作者 V.S.Markevich T.A.Kovaleva 《Global Geology》 2016年第4期216-229,共14页
The Lipovtsy flora originates mostly from the synonymous Formation exposed at the coal quarries in the Razdolnaya( Suifun) River Basin in Heilongjiang Province( China) and Primorye Region( Russia). The thorough study ... The Lipovtsy flora originates mostly from the synonymous Formation exposed at the coal quarries in the Razdolnaya( Suifun) River Basin in Heilongjiang Province( China) and Primorye Region( Russia). The thorough study of this flora has revealed its high diversity and abundance. One of the most prominent groups in the Lipovtsy flora is the ferns. Next in diversity are conifers( Miroviaceae,Taxodiaceae,Podozamitaceae,Taxaceae,Cephalotaxaceae). It was revealed the remarkable quantity of bennettitalean remains( 24 taxa). The main peculiarity of this flora is the appearance of first angiosperms( pollen,dispersed cuticle,leaves). The fine preservation of the cuticles from the coals allows us to research the taxonomical composition of peat-forming plants and clear main components of the swamp plant communities. These plants supplied the material for the accumulation of resinite coals on the territory of Razdolnaya River Basin were conifers Miroviaceae,taxodialeans,bennettites,as well as gleicheniaceous and cyatheaceous ferns. 展开更多
关键词 fossil plants SPORES POLLEN floral assemblages Lipovtsy Formation Razdolnaya (Suifun River Basin Primorye region
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Effects of Vegetation Type on Surface Elevation Change in Liaohe River Delta Wetlands Facing Accelerated Sea Level Rise 被引量:5
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作者 WANG Guodong WANG Ming +3 位作者 JIANG Ming LYU Xianguo HE Xingyuan WU Haitao 《Chinese Geographical Science》 SCIE CSCD 2017年第5期810-817,共8页
Rising sea levels threaten the sustainability of coastal wetlands around the globe. The ability of coastal marshes to maintain their position in the intertidal zone depends on the accumulation of both organic and inor... Rising sea levels threaten the sustainability of coastal wetlands around the globe. The ability of coastal marshes to maintain their position in the intertidal zone depends on the accumulation of both organic and inorganic materials, and vegetation is important in these processes. To study the effects of vegetation type on surface elevation change, we measured surface accretion and elevation change from 2011 to 2016 using rod surface elevation table and feldspar marker horizon method (RSET-MH) in two Phragmites and two Suaeda marshes in the Liaohe River Delta. The Phragmites marshes exhibited higher rates of surface accretion and elevation change than the Suaeda marshes. The two Phragmites marsh sites had average surface elevation change rates at 8.78 mm/yr and 9.26 mm/yr and surface accretion rates at 17.56 mm/yr and 17.88 mm/yr, respectively. At the same time, the two Suaeda marsh sites had average surface elevation change rates at 5.77 mmJyr and 5.91 mm/yr and surface accretion rates at 13.42 mm/yr and 14.38 mm/yr, respectively. The elevation change rates in both the Phragmites marshes and the Suaeda marshes in the Liaohe River Delta could keep pace and even continue to gain elevation relative to averaged sea level rise in the Bohai Sea reported by the 2016 State Oceanic Administration, Peo- ple's Republic of China projection (2.4-5.5 mm/yr) in current situations. Our data suggest that vegetation is important in the accretionary processes and vegetation type could regulate the wetland surface elevation. However, the vulnerability of coastal wetlands in the Liaohe River Delta need further assessment considering the accelerated sea level rise, the high rate of subsidence, and the declining sediment delivery, especially for the Suaeda marshes. 展开更多
关键词 sea level rise wetland elevation surface accretion Phragmites marsh Suaeda marsh Liaohe River Delta
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Orientation of larval and juvenile horseshoe crabs Limulus polyphemus to visual cues: Effects of chemical odors 被引量:2
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作者 Julie M.MEDINA Richard A.TANKERSLEY 《Current Zoology》 SCIE CAS CSCD 北大核心 2010年第5期618-633,共16页
Adult horseshoe crabs Limulus polyphemus have long served as models for the study of vision in marine arthropods. Yet, little is known about the ability of early life history stages to detect and respond to visual cue... Adult horseshoe crabs Limulus polyphemus have long served as models for the study of vision in marine arthropods. Yet, little is known about the ability of early life history stages to detect and respond to visual cues. We examined the visually directed movements of larvae and first stage juveniles to horizons containing dark visual targets of different sizes. The study tested the hypotheses that (1) larval and juvenile crabs can detect and respond to visual targets and (2) the direction of orientation varies with the presence of chemical cues associated with settlement habitats. Orientation of larval and juvenile crabs to rectangles subtending angles from 30--330~ was tested in a circular arena containing water that either lacked estuarine chemical cues (offshore water) or contained odors from aquatic vegetation or known predators. In the absence of chemical odors, larvae oriented toward and juveniles moved away from dark horizons subtending angles 〉 60~. When placed in water containing chemical odors from potential nursery habitats, including the seagrasses Halodule wrightii and Syringodium filiforme, crabs reversed their direction of orientation relative to their responses in offshore water. Odors from two known predators, the mummichug Fundulus grandis and blue crab Callinectes sapidus, had no affect on the orientation of larvae. Yet, juveniles responded to both odors by moving toward the visual target. Results support the hypothesis that the visual orientation of larval and juvenile horseshoe crabs changes upon exposure to habitat and predator cues and that the direction of the response undergoes an ontogenetic shift following metamorphosis 展开更多
关键词 ORIENTATION Visual cues Chemical odors
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