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Effect of grass coverage on sediment yield in the hillslope-gully side erosion system 被引量:17
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作者 李勉 姚文艺 +2 位作者 丁文峰 杨剑锋 陈江南 《Journal of Geographical Sciences》 SCIE CSCD 2009年第3期321-330,共10页
By scouring experiments, the changeable process and characteristics of sediment yield in the hillslope-gully side erosion system with different coverage degrees and spatial locations of grass were studied. Five grass ... By scouring experiments, the changeable process and characteristics of sediment yield in the hillslope-gully side erosion system with different coverage degrees and spatial locations of grass were studied. Five grass coverage degrees of 0, 30%, 50%, 70%, 90%, three spatial locations of grass (upslope, mid-slope, low-slope) and two water inflow rates of 3.2 L/min, 5.2 L/min were applied to a 0.5 by 7 m soil bed in scouring experiments. Results showed that the sediment yield decreased with the increase of grass coverage degree at 3.2 L/min water inflow rate in scouring experiments and the sediment yield with different grass locations on the sloping surface was in the order of upper 〉 middle 〉 lower. At 5.2 L/min water inflow rate, the differences of sediment yield among various grass coverage degrees were increased, whereas the changeable tendency of sediment yield with different grass locations on the whole sloping surface was not very obvious. The proportion of sediment yield from the gully side increased in an exponential relationship with the increase of grass coverage degree When the grass was located on the lower position of hillslope, the influence for accelerating gully erosion is the greatest. 展开更多
关键词 grass coverage hillslope-gully side erosion system scouring experiment sediment yield
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Simplified Dynamic Models of Grass Field Ecosystem 被引量:1
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作者 曾庆存 曾晓东 卢佩生 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1994年第4期385-390,共6页
Some simplified dynamic models of grass field ecosystem are developed and investigated. The maximum simplified one consists of two variables, living grass biomass and soil wetness. The analyses of such models show tha... Some simplified dynamic models of grass field ecosystem are developed and investigated. The maximum simplified one consists of two variables, living grass biomass and soil wetness. The analyses of such models show that there exists only desert regime without grasses if the precipitation p is less than a critical value pc; the grass biomass continuously depends on p if the interaction between grass biomass and the soil wetness is weak, but the strong interaction results in the bifurcation of grass biomass in the vicinity of pc: the grass biomass is rich as p > pc, but it becomes desertification as p<pc. Periodic solutions also exist in the model, if the seasonal cycle of model's parameters is introduced. An improved model consists of three variables, i.e. the living grass biomass x, the nonliving grass biomass accumulated on the ground surface y and the soil wetness z. The behaviours of such three variables model are more complicated. The initial values of y and z play a very important role. 展开更多
关键词 Dynamic model grass field ecosystem BIFURCATION
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Infiltration pattern beneath shrub canopy and interspace grass patches in typical steppe ecosystems of Inner Mongolia, China 被引量:2
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作者 ZHANG Si-yi LI Xiao-yan +1 位作者 PENG Hai-ying ZHANG Zhi-hua 《地球环境学报》 2012年第6期1117-1125,共9页
Water is the most critical factor for controlling die vegetation pattern in arid and semiarid regions.Using a dye-tracing experiment,we analyzed the infiltration pattern beneath shrub canopy and interspace grass patch... Water is the most critical factor for controlling die vegetation pattern in arid and semiarid regions.Using a dye-tracing experiment,we analyzed the infiltration pattern beneath shrub canopy and interspace grass patches in typical steppe ecosystems.The dye coverage,uniform infiltration depth,maximum infiltration depth,total stained area and heterogeneous infiltration stained area were measured by two indices,the maximum infiltration depth index(MIDI)and heterogeneous infiltration index(HII),which were calculated by processing dye-stained photos.The MIDI and HII of soil under shrubs were 1.41±0.14 and 0.29±0.068,respectively,and larger than those of grass soil,1.26±0.14 and0.20±0.076.Using the MIDI,HII,field soil moisture and rainfall data,the infiltration depth and heterogeneous infiltration amount for 26 nature rainfall events were calculated.The results imply that water can infiltrate to a deeper layer beneath shrub canopy than beneath grass patches and that more water infiltration occurs beneath shrub canopy than beneath grass patches.These results are of prime importance for arid and semiarid ecosystems with a limited water supply due to high evaporation and low precipitation. 展开更多
关键词 Infiltration pattern dye-tracing SHRUB grass patches typical steppe ecosystems
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The Building of Grass-roots Agricultural Technology Extension System
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作者 Wen YANG Jian HUANG 《Asian Agricultural Research》 2013年第1期31-35,共5页
Based on the survey of 154 farmers in Guiyang City, we analyze the basic situation of building of grass-roots agricultural technology extension system in Guiyang City. Then we point out some problems in the building o... Based on the survey of 154 farmers in Guiyang City, we analyze the basic situation of building of grass-roots agricultural technology extension system in Guiyang City. Then we point out some problems in the building of grass-roots agricultural technology extension system in Guiyang City: the function of grass-roots agricultural technology extension center weakens; the content of agricultural technology extension is difficult to adapt to farmers' needs for technology; the extension mode of agricultural technology departments does not adapt to the needs of modern agriculture. In order to perfect the building of grass-roots agricultural technology extension system, the countermeasures and recommendations are put forth as follows: strengthening the input of funds, and ensuring that the basic work of public welfare agricultural technology extension is smoothly carried out; innovating upon the system, and improving the function of grass-roots agricultural technology extension center; implementing management on agricultural technology extension personnel's performance, and promoting the extension efficiency; strengthening the building of extension team in rural areas, and cultivating high-quality agricultural technology extension personnel; exploring the advanced service mode to meet farmers' needs. 展开更多
关键词 grass ROOTS AGRICULTURAL TECHNOLOGY EXTENSION Buil
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Construction of Rural Grass-roots Water Conservancy Service System in the Context of Institutional Changes
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作者 Ning WANG 《Asian Agricultural Research》 2015年第11期49-52,共4页
At present,it is urgent to solve problems of reforming and improving grass-roots water conservancy management mode in rural areas and improving rural water conservancy public service ability. Through analyzing institu... At present,it is urgent to solve problems of reforming and improving grass-roots water conservancy management mode in rural areas and improving rural water conservancy public service ability. Through analyzing institutional changes of grass-roots water conservancy management in rural areas,this paper discussed current situations and outstanding problems in grass-roots water conservancy services in rural areas of Kunming City. On the basis of current situations and problems,it came up with policy recommendations from reform of management institutions,reform of personnel system,construction of human resources,development of rural water use cooperation organizations,and improvement of fund input mechanism,to build rural grass-roots water conservancy service system. 展开更多
关键词 INSTITUTIONAL CHANGES RURAL areas grass-roots water conservancy service system POLICY RECOMMENDATIONS
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Curcumin attenuates ochratoxin A and hypoxia co‑induced liver injury in grass carp(Ctenopharyngodon idella)by dual targeting endoplasmic reticulum stress and apoptosis via reducing ROS content
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作者 Liangqin Wu Piao Zhao +6 位作者 Pei Wu Weidan Jiang Yang Liu Hongmei Ren Xiaowan Jin Xiaoqiu Zhou Lin Feng 《Journal of Animal Science and Biotechnology》 2025年第1期408-423,共16页
Background Ochratoxin A(OTA)is a toxin widely found in aquafeed ingredients,and hypoxia is a common prob-lem in fish farming.In practice,aquatic animals tend to be more sensitive to hypoxia while feeds are contaminate... Background Ochratoxin A(OTA)is a toxin widely found in aquafeed ingredients,and hypoxia is a common prob-lem in fish farming.In practice,aquatic animals tend to be more sensitive to hypoxia while feeds are contaminated with OTA,but no studies exist in this area.This research investigated the multiple biotoxicities of OTA and hypoxia combined on the liver of grass carp and explored the mitigating effect of curcumin(CUR).Methods A total of 720 healthy juvenile grass carp(11.06±0.05 g)were selected and assigned randomly to 4 experi-mental groups:control group(without OTA and CUR),1.2 mg/kg OTA group,400 mg/kg CUR group,and 1.2 mg/kg OTA+400 mg/kg CUR group with three replicates each for 60 d.Subsequently,32 fish were selected,divided into nor-moxia(18 fish)and hypoxia(18 fish)groups,and subjected to hypoxia stress for 96 h.Results CUR can attenuate histopathological damage caused by coming to OTA and hypoxia by reducing vacu-olation and nuclear excursion.The alleviation of this damage was associated with the attenuation of apoptosis in the mitochondrial pathway by decreasing the expression of the pro-apoptotic proteins Caspase 3,8,9,Bax,and Apaf1 while increasing the expression of the anti-apoptotic protein Bcl-2,and attenuation of endoplasmic reticulum stress(ERS)by reducing Grp78 expression and chop levels.This may be attributed to the fact that the addi-tion of CUR increased the levels of catalase(CAT)and glutathione reductase(GSH),increased antioxidant capacity,and ensured the proper functioning of respiratory chain complexes I and II,which in turn reduced the high produc-tion of reactive oxygen species(ROS),thus alleviating apoptosis and ERS.Conclusions In conclusion,our data demonstrate the effectiveness of CUR in attenuating liver injury caused by the combination of OTA and hypoxia.This study confirms the feasibility and efficacy of adding natural products to mitigate toxic damage to aquatic animals. 展开更多
关键词 APOPTOSIS CURCUMIN Endoplasmic reticulum stress grass carp HYPOXIA Ochratoxin A Oxidative damage
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Single-cell atlas of grass carp(Ctenopharyngodon idella)peripheral blood IgM^(+)B cells provides insights into B cell-mediated immune responses in teleost fish
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作者 Yi-Ru Pan Xue-Qing Han +2 位作者 Tian-Tian Tian Yong-An Zhang Xu-Jie Zhang 《Zoological Research》 2025年第5期953-966,共14页
Teleost peripheral blood contains a remarkably high proportion of B cells,accounting for 15%-50%of circulating lymphocytes.However,their immune responses to bacterial infection are yet to be elucidated.In the present ... Teleost peripheral blood contains a remarkably high proportion of B cells,accounting for 15%-50%of circulating lymphocytes.However,their immune responses to bacterial infection are yet to be elucidated.In the present study,10×Genomics single-cell RNA sequencing(scRNA-seq)was employed to characterize the transcriptomic landscape of peripheral blood IgM^(+)B cells in grass carp(Ctenopharyngodon idella)following challenge with Aeromonas hydrophila,a major aquatic pathogen.Six transcriptionally distinct IgM^(+)B cell subpopulations were identified,including(im)mature B cells,innate B cells,proliferating B cells,IgD^(high)B cells,and two infection-induced subsets denoted as infectionⅠandⅡB cells.Bacterial infection altered the cellular heterogeneity of IgM^(+)B cells,triggered metabolic reprogramming in(im)mature and innate B cell subpopulations,and enhanced the immunological activation of circulating B cells.Notably,infectionⅠB cells demonstrated robust induction of interferonφ1(IFNφ1),a type I IFN,following A.hydrophila exposure.This induction was further validated through in vitro bacterial stimulation,indicating that teleost B cells actively contribute to innate antibacterial responses through IFN signaling.Additionally,the IgD^(high)B cell subpopulation remained consistently present in peripheral blood across both infected and uninfected states,pointing to a constitutive and likely mature phenotype.These findings significantly advance our understanding of the heterogeneity of peripheral blood IgM^(+)B cells and provide new insights into IgM^(+)B cell-mediated immune responses in teleost fish. 展开更多
关键词 ScRNA-seq B cells Peripheral blood grass carp Bacterial infection
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Growing Quality Grass for the Plateau
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作者 Xiangan Huang Wenjuan 《China's Tibet》 2025年第5期46-49,共4页
In mid-June,Kangmar County was swept by strong mountain winds.Just after stepping off the plane,Yu Chengqun hurriedly led his team of doctoral students and postdoctoral researchers from the Grass-Industry Inn ovation ... In mid-June,Kangmar County was swept by strong mountain winds.Just after stepping off the plane,Yu Chengqun hurriedly led his team of doctoral students and postdoctoral researchers from the Grass-Industry Inn ovation Team straight to the grassland. 展开更多
关键词 strong mountain winds grass PLATEAU mid june Yu Chengqun Kangmar County doctoral students quality
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Grass hay mixed‑in creep feed or separately‑fed differentially affects digestive development in pre‑and post‑weaning piglets
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作者 Renjie Yao Tetske G.Hulshof +4 位作者 Hubèrt M.J.van Hees An Cools Mattijs Merckx Dominiek Maes Geert P.J.Janssens 《Journal of Animal Science and Biotechnology》 2025年第5期2302-2321,共20页
Background Based on observations in feral pigs,the role of dietary fibre and structure may be underestimated in suckling piglet nutrition.This study investigated the effect of grass hay offered to suckling piglets eit... Background Based on observations in feral pigs,the role of dietary fibre and structure may be underestimated in suckling piglet nutrition.This study investigated the effect of grass hay offered to suckling piglets either separately or included in their creep feed,combined with nursery diets with or without grass pellet inclusion on growth performance and gastrointestinal development.Methods Thirty-six litters(14–15 piglets per litter)were divided into three equal groups of 12 litters per treatment during the suckling phase:control group(CON)received regular creep feed;GH group received chopped grass hay as-is in separate feeders alongside regular creep feed;PGH group received regular creep feed but barley and wheat were replaced by 28%grass pellets.After weaning(d 23),each litter was split into two dietary treatments in a splitplot design(pre-wean treatment as main plot).Two of the pre-wean diets were also offered until d 14 post-weaning,i.e.,CON(CON nursery diet,CON-C,GH-C,PGH-C)and PGH(GH nursery diet,CON-GH,GH-GH,PGH-GH).Thereafter,transitioning to a diet containing 13%wheat/barley or grass pellets,respectively,until d 39 post-weaning.Gastrointestinal morphology,gene expression of intestinal nutrient transporters and barrier proteins,metabolite profile and microbiota were assessed on the day before weaning,d 10 and d 38 post-weaning.A total of 24 piglets were sacrificed at each dissection point.Results At weaning,GH group had consumed 7 g/piglet grass hay,and PGH group had consumed 46 g/piglet creep feed.One day before weaning,GH piglets showed heavier emptied small intestine(P=0.044)and colon(P=0.065),higher SCFA production in proximal segments and lower SCFA production in colon(P<0.05).Higher abundance of Prevotellaceae NK3b31 group was observed in caecal and colonic content of PGH compared to GH group(P<0.05),and PGH group showed a lower energy conversion ratio(net energy intake/gain,P=0.035).Following weaning,GH nursery group had a reduced average daily gain(226 vs.183 g,P<0.001)during d 0–14,while this group showed compensatory growth afterwards(P=0.056).Main plot effects on increased expressions of CLDN3 and FFAR2 were observed in GH and PGH by d 38 post-weaning(P<0.05).An interaction effect showed greater luminal abundance of the Prevotellaceae NK3b31 group in GH-GH and PGH-GH groups compared to CON-GH on d 38.The GH nursery diet showed a better energy conversion ratio(P=0.006)with no influence on body weight and their SCFA production shifted towards proximal segments.Conclusion In conclusion, feeding a structured and fibre-rich diet to suckling piglets enhance their digestive tractdevelopment and adapt their microbiome to fibre digestion in later life. Maintaining a fibre-rich diet from sucklingto nursery is recommended, though this come with a transient reduction in weight gain caused by lower feed intakethat, however, can be recovered afterwards accompanied with an optimized energy conversion ratio. 展开更多
关键词 Dietary fibre Gastrointestinal development grass hay Suckling piglets
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Space and Power-An Interpretation of“The Grass is Singing”from the Perspective of Spatial Criticism Theory
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作者 LIU Xue-ru 《Journal of Literature and Art Studies》 2025年第5期404-407,共4页
Nobel Prize winner Doris Lessing is a renowned writer in the contemporary British literary scene.Her debut novel The Grass is Singing is based on a case in which a black manservant kills a white mistress who is poor a... Nobel Prize winner Doris Lessing is a renowned writer in the contemporary British literary scene.Her debut novel The Grass is Singing is based on a case in which a black manservant kills a white mistress who is poor and mentally unbalanced.Doris Lessing arranges a tangible form of perception for the expression of the colonial discourse in the work by seeking the relationship between spatial structure and the writer’s value.This paper focuses on the spatial writing in The Grass is Singing and analyses it in depth with reference to the spatial critical theories of Henri Lefebvre and Michel Foucault.The oppressed and enslaved characters in the novel are analysed from three perspectives:physical space,social space and mental space respectively to explore how power oppression is made visible through space and the writer’s critique of colonial relations and racial discrimination as well as unequal gender relations. 展开更多
关键词 The grass is Singing Doris Lessing SPACE POWER spatial criticism colonial discourse
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On Translation Strategies for the Grass Imagery in Classical Chinese Poetry:A Cultural Semiotic Perspective
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作者 REN Rui LI Yutong SUN Yujingjing 《Sino-US English Teaching》 2025年第2期42-47,共6页
Grass constitutes a vital poetic imagery in classical Chinese poetry,embodying multifaceted symbolic connotations ranging from the tenacity of life to sentiments of separation and nostalgic longing.The translation of ... Grass constitutes a vital poetic imagery in classical Chinese poetry,embodying multifaceted symbolic connotations ranging from the tenacity of life to sentiments of separation and nostalgic longing.The translation of this botanical motif necessitates not merely lexical equivalence,but more importantly,the transmission of its profound cultural resonance and aesthetic essence.This study posits that effective rendition of grass imagery should adopt an integrative approach synthesizing the objectives of cultural translation with the intrinsic aesthetic characteristics of classical poetry.Through systematic analysis of the cultural semiotics embedded in grass symbolism,the research investigates practical translation techniques at lexical,syntactic,and stylistic dimensions.The findings aim to contribute to the theoretical framework of cultural image translation in Chinese poetic tradition while providing methodological references for cross-cultural interpretation of classical verse.By bridging cultural semiotics with translation praxis,this investigation seeks to advance the intercultural communication of Chinese poetic heritage through nuanced treatment of its botanical symbolism. 展开更多
关键词 classical Chinese poetry grass translation strategies cultural image
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Efficiency of Elephant Grass(Cenchrus purpureus)as Bioaccumulator Plant and Soil Weathering Enhancer
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作者 Naira A.Ibrahim Zavier Smith +3 位作者 Hayleigh Harrison Subrata C.Roy Saiful M.Islam William B.Evan 《Journal of Environmental & Earth Sciences》 2025年第5期520-533,共14页
The increasing challenges of environmental degradation,soil erosion,and climate change have driven interest in sustainable solutions like enhanced weathering(EW)and phytoremediation.Elephant Grass(Cenchrus purpureus),... The increasing challenges of environmental degradation,soil erosion,and climate change have driven interest in sustainable solutions like enhanced weathering(EW)and phytoremediation.Elephant Grass(Cenchrus purpureus),a fast-growing perennial species,shows promise as a bioaccumulator and agent for soil weathering.This study assessed the potential of C.purpureus to improve soil quality through heavy metal(HM)uptake and EW facilitation.A 60-day greenhouse pot experiment at Jackson State University evaluated plant performance in soils amended with metabasalt rock powder at 1:1 and 2:1 rock-to-soil ratios.Biomass,growth,and HM concentrations in roots and shoots were measured via ICP-MS after wet digestion.Soil pH and magnesium(Mg)release were also monitored to assess weathering and carbon drawdown.Results showed that C.purpureus accumulated more HMs in roots at higher amendment levels,while at lower levels,metals like As,Cd,and Cr were more translocated to shoots,enhancing phytoextraction potential.High treatment favored Fe and Al uptake,possibly reducing toxic metal accumulation in edible parts.Notably,C.purpureus contributed to the weathering of 38%of metabasalt rock,leading to a 42%increase in Mg release.With high biomass,HM tolerance,and weathering capacity,C.purpureus offers a sustainable strategy for soil remediation,improved soil health,and potential support for renewable energy systems. 展开更多
关键词 Elephant grass(Cenchrus purpureus) PHYTOREMEDIATION Heavy Metals BIOENERGY Soil Enhancer
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Mythical Tales of Mountains and Seas:Foxtail Grassland
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作者 Hai Shui Yan Qing Shi Yi 《China Book International》 2025年第6期116-117,共2页
On the grassland,flowers bloomed again and again.Little fox Lili became acquainted with many of them:the pink Indian cress,the red Rubyleaf Bloom,the yellow Sunny Sourblossom,and the blue grass flowers.Before she knew... On the grassland,flowers bloomed again and again.Little fox Lili became acquainted with many of them:the pink Indian cress,the red Rubyleaf Bloom,the yellow Sunny Sourblossom,and the blue grass flowers.Before she knew it,Lili had arrived at her very first summer,and with it,the day of her first-ever hike. 展开更多
关键词 red rubyleaf bloom yellow sunny sourblossom blue grass flowers MOUNTAINS pink indian cress FLOWERS mythical tales SEAS
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Design of Control and Monitor System Applied in Artificial Grass Tufting Machine
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作者 于永民 宋佳玲 《Journal of Donghua University(English Edition)》 EI CAS 2015年第2期294-299,共6页
Based on the control requirements of artificial grass tufting machine,an overall plan is proposed on control of CANopen bus.In the control system,on the basis of CoDeSys soft PLC technology of fieldbus control system,... Based on the control requirements of artificial grass tufting machine,an overall plan is proposed on control of CANopen bus.In the control system,on the basis of CoDeSys soft PLC technology of fieldbus control system,LMC20 realizes the communication by making CANopen bus connect with ATV71,OTB module and these underlying slave stations.The humanized operation interface is realized by touch screens and user-friendly application which is developed through CoDeSys,and detailed analysis of the monitor system and the principle and method of monitor system are also provided in the paper. 展开更多
关键词 CANopen monitor slave connect friendly touch realized servo underlying hardware
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Comparative Microsatellite Analysis of Grass Carp Genomes of Two Gynogenetic Groups and the Xiangjiang River Group 被引量:10
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作者 郑康 林凯东 +1 位作者 刘正华 罗琛 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第4期321-330,共10页
The genomes of three groups of grass carp, namely the Xiangjiang River grass carp group (Xiangjiang group), a one-generation artificially induced meio-gynogenetic grass carp group (meio-gynogenetic-1 group), and a... The genomes of three groups of grass carp, namely the Xiangjiang River grass carp group (Xiangjiang group), a one-generation artificially induced meio-gynogenetic grass carp group (meio-gynogenetic-1 group), and a two-generation artificially induced meio-gynogenetic grass carp group (meio-gynogenetic-2 group), were comparatively analyzed with microsatellite markers. Genetic polymorphism had been observed in the Xiangjiang group and most of the examined loci had more than two alleles. But the degree of genetic diversity was not very high. Although all the examined genetic loci in the analyzed individuals were in homozygous state, the genotypes of different individuals of the group were not identical in the meio-gynogenetic-1 group. In the meio-gynogenetic-2 group, not only the examined genetic loci of each individual were homozygous but also the genotypes of all the analyzed individuals of the group were the same. These results suggested that the examined meio-gynogenetic-2 group is a homozygous group and homozygous clone could be produced by continuous artificial induction of gynogenesis for two generations. It was found that the polymorphism existed not only at the allele level but also at the locus level; many alleles of the microsatellite loci and some of the microsatellite loci had been lost during the process of artificial gynogenesis. Therefore, both protection of the diversity of natural grass carp resource and selection of homozygous traits with desired economic genotypes are very important aspects for grass carp breeding. 展开更多
关键词 grass carp GYNOGENESIS GENOME microsatellite locus
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Comparative Analysis on Growth and Morphology in Yangtze River ♀,Zhujiang River ♂ and Their F_1 Hybrids of Juvenile Grass Carp 被引量:6
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作者 傅建军 王荣泉 +3 位作者 刘峰 宣云峰 朱树人 李家乐 《Agricultural Science & Technology》 CAS 2009年第5期119-122,共4页
[ Objective] The aim of this study was to investigate the growth and morphological characteristics of juvenile hybrids of grass carp. [Method] Three inbred generations of YR (Yangtze River stock ♀×Yangtze River... [ Objective] The aim of this study was to investigate the growth and morphological characteristics of juvenile hybrids of grass carp. [Method] Three inbred generations of YR (Yangtze River stock ♀×Yangtze River stock ♂ ), ZR (Zhujiang River stock ♀ ×Zhujiang River stock♂ ) and hybrids F1 ( Yangtze River stock ♀ × Zhujiang River stock ♂ ) were established, and their growth or morphological data were also measured. [ Result] The orders of body weight, standard length and absolute growth rate were F1 〉 ZR 〉 YR. No significant difference was found in body weight or standard length of 50 day-old generations ( P〉0. 05), while there was an extremely significantly difference in those of 170 day-old generations ( P 〈0.01 ). However, the absolute growth rate of F1 was 20.00% and 50.00% higher than that of ZR and YR respectively, and no significant difference was found between F1 and ZR ( P 〉 0.05), but significant difference between F1 and YR ( P 〈 0.05). F1 showed a significant hybrid vigor with rate of 20.09%. There was no significant difference among three inbred generations in standard length/total length ( P 〉 0.05), while significant difference in head length/total length, body height/standard length and body width/standard length ( P 〈 0.05), which indicated that F1 had the characteristics of shorter head, higher and wider body. [ Conclusion]F1 has advantages in growth performance and morphological characteristics. 展开更多
关键词 grass carp Hybrid Growth performance Morphological parameter
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Adaptability Comparison of Chinese Milk Vetch (Astragalus sinicus) Varieties for Double-rice Cropping System in Hunan 被引量:4
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作者 鲁艳红 廖育林 +5 位作者 周兴 涂赛军 聂军 谢坚 杨曾平 曹卫东 《Agricultural Science & Technology》 CAS 2015年第9期1902-1906,共5页
Five Chinese milk vetch(Astragalus sinicus) varieties were selected to make a comparison in order to screen effective varieties which could suit for the double-rice cropping system of Hunan Province. The results sho... Five Chinese milk vetch(Astragalus sinicus) varieties were selected to make a comparison in order to screen effective varieties which could suit for the double-rice cropping system of Hunan Province. The results showed that the growth period of Xiangzi 2 is shorter than that of Xiangfei 2, Xiangfei 3 and Yujiangdaye,and is similar to that of Xinyang Chinese milk vetch. The full-bloom stage of Xiangzi 2 is also similar to Xinyang variety and obviously earlier than that of the other three varieties. The fresh grass yield of Xiangzi 2 in full-bloom stage is 23 842.5kg/hm^2, which increases by 39.9% compared with Xinyang variety. Nitrogen content in the fresh grass of Xiangzi 2 is higher than that of the other four varieties. In conclusion, Xiangzi 2 is an extremely early-blossoming and early-maturing Chinese milk vetch variety with moderate fresh grass yield, high nutrient contents, stable characters and wide adaptability. So, Xiangzi 2 is suitable for planting in double-rice cropping region in Hunan Province and other same latitude regions which have similar ecological conditions. 展开更多
关键词 Chinese milk vetch(Astragalus sinicus) Growth period Full-bloom stage Fresh grass yield Nutrient content
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GRASS文件预留系统的设计与实现 被引量:3
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作者 黄秋兰 朱随江 +1 位作者 程耀东 陈刚 《核电子学与探测技术》 CAS CSCD 北大核心 2011年第9期969-972,共4页
GRASS(Grid-enabled Advanced Storage System)分级存储系统主要负责提供海量数据的分级存储管理和数据迁移功能。目前,GRASS系统的数据迁移仅包含存储池水位、数据迁移时间间隔等系统级别的策略,而缺乏针对文件的精细控制。针对该问题... GRASS(Grid-enabled Advanced Storage System)分级存储系统主要负责提供海量数据的分级存储管理和数据迁移功能。目前,GRASS系统的数据迁移仅包含存储池水位、数据迁移时间间隔等系统级别的策略,而缺乏针对文件的精细控制。针对该问题,设计了GRASS文件预留系统,实现基于用户级的数据预留,目的是为了高能物理的研究人员可以根据需要将自己指定的文件预留在磁盘上,从而避免自己要访问的文件被迁移到磁带库中去,从而提高用户访问数据的速度。首先介绍了GRASS系统,并给出了GRASS文件预留系统的基本架构,接着详细阐述系统的设计和实现,最后给出了系统的运行结果及测试分析。 展开更多
关键词 BES grass 数据迁移 分级存储管理
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Main Resources of Ornamental Grass and Their Ornamental Value Evaluation in Kunming 被引量:3
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作者 岳锋 樊智丰 杨斌 《Journal of Landscape Research》 2010年第1期57-61,共5页
Ornamental value of 45 ornamental grass resources was evaluated by grey-correlation analysis based on the full investigation and research of ornamental grass resources in Kunming and with the characters of ornamental ... Ornamental value of 45 ornamental grass resources was evaluated by grey-correlation analysis based on the full investigation and research of ornamental grass resources in Kunming and with the characters of ornamental value, height, color of leaf and inflorescence as evaluating indexes. The results showed that the correlation degree with ideal species of 34 in the 50 ornamental grasses was higher than 0.6; Saccharum fallax, Erianthus longisetosus, Erianthus rufipilus, Zizania latifolia, etc. had better ornamental effects and their correlation degree with ideal species were 0.863 6, 0.812 5, 0.900 0 and 0.815 5, they can be used for landscaping directly. 展开更多
关键词 ORNAMENTAL grass Grey-correlation analysis ORNAMENTAL VALUE evaluation
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The Therapeutic Effect of Onion on the Pathogenic Bacteria of Gill Rot Disease in Grass Carp 被引量:2
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作者 徐大勇 韦汉群 张文丽 《Agricultural Science & Technology》 CAS 2008年第1期117-120,共4页
[Objective] The curative effect of onion on bacterial rotted gill disease in grass carp was researched [Method] The combination method of taking medicine through oral and spraying was used to cure sick grass carp for ... [Objective] The curative effect of onion on bacterial rotted gill disease in grass carp was researched [Method] The combination method of taking medicine through oral and spraying was used to cure sick grass carp for 1 period of treatment in room under artificial conditions. [Result] Different concentrations of onion generated different cure rates. When the combination was adding 1.0% - 2.0% medicine into feed and spraying 2.0 g,/m3 - 5.0 g,/m3, the curative result was the best with cure rate was 70% -90% [ Conclusion] The onion was effective on curing bacterial rotted gill disease in grass carp and could be taken as curative medicine. 展开更多
关键词 ONION Bacterial rotted gill disease Oral method Spraying method grass carp
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