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Reproductive height determines the loss of clonal grasses with nitrogen enrichment in a temperate grassland
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作者 Xu Chen Haining Lu +4 位作者 Zhengru Ren Yuqiu Zhang Ruoxuan Liu Yunhai Zhang Xingguo Han 《Plant Diversity》 SCIE CAS CSCD 2024年第2期256-264,共9页
Tall clonal grasses commonly display competitive advantages with nitrogen(N)enrichment.However,it is currently unknown whether the height is derived from the vegetative or reproductive module.Moreover,it is unclear wh... Tall clonal grasses commonly display competitive advantages with nitrogen(N)enrichment.However,it is currently unknown whether the height is derived from the vegetative or reproductive module.Moreover,it is unclear whether the height of the vegetative or reproductive system regulates the probability of extinction and colonization,and determines species diversity.In this study,the impacts on clonal grasses were studied in a field experiment employing two frequencies(twice a year vs.monthly)crossing with nine N addition rates in a temperate grassland,China.We found that the N addition decreased species frequency and increased extinction probability,but did not change the species colonization probability.A low frequency of N addition decreased species frequency and colonization probability,but increased extinction probability.Moreover,we found that species reproductive height was the best index to predict the extinction probability of clonal grasses in N-enriched conditions.The low frequency of N addition may overestimate the negative effect from N deposition on clonal grass diversity,suggesting that a higher frequency of N addition is more suitable in assessing the ecological effects of N deposition.Overall,this study illustrates that reproductive height was associated with the clonal species extinction probability under N-enriched environment. 展开更多
关键词 ANPP Biodiversity Clonal grass COLONIZATION EXTINCTION Nitrogen addition frequency
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Effect of Using Israel Napier Grass in Feed Ration on Growth Performance of Local Chicken of Cambodia
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作者 Sophea Rous Tola Ka +2 位作者 Sokha Thim Sath Keo Kouch Theng 《Journal of Environmental Science and Engineering(B)》 2024年第1期47-52,共6页
This study investigated the effect of Israel grass in feed formulation on growth performance of local chicken.The study was conducted from October 2023 until January 2024 in Kampong Chheutel Institute of Technology.Th... This study investigated the effect of Israel grass in feed formulation on growth performance of local chicken.The study was conducted from October 2023 until January 2024 in Kampong Chheutel Institute of Technology.The CRD(Completely Randomized Design)was used with 4 treatments and 4 replications.The local chicks were purchased from local famer at 1 day old and kept in whole pen by feeding commercial feed.At 21 days old the total 320 chicks were allocated into experimental treatments.The 4 feed formulas based on the level of Israel grass added such as 0,5%,7%and 9%,were called T1(control),T2,T3 and T4 respectively.The result showed that body weight gain,feed intake,ADG(Average Daily Gain)and FCR(Feed Conversion Ratio)in all treatments were not significantly different(p>0.05).However,there was strong correlation between living weight with carcass of al treatments,but no difference among carcass percentage of local chicken for all different diet in this study.In conclusion,the Israel grass did not affect growth performance of local chickens and can be used to replace some expensive feed ingredient,such as rice bran. 展开更多
关键词 Israel grass growth performance CARCASS local chickens
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Camalote Grass (Paspalum fasciculatum Willd) as a Sustainable Raw Material for the Production of Lignocellulosic Ethanol
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作者 María Luz May-Reyes Cintya Valerio-Cárdenas +3 位作者 Gloria Ivette Bolio-López Manuel Mateo Hernández-Villegas Miguel Ángel Velázquez-Carmona Patricia De la Cruz-Burelo 《Journal of Sustainable Bioenergy Systems》 2024年第2期23-33,共11页
The current trend of replacing a percentage of gasoline with ethanol has promoted the development of new processes for its production from lignocellulosic biomass. This work reports the production of ethanol from the ... The current trend of replacing a percentage of gasoline with ethanol has promoted the development of new processes for its production from lignocellulosic biomass. This work reports the production of ethanol from the Camalote grass (Paspalum fasciculatum Willd). The lignocellulosic biomass was subjected to acid hydrolysis at 125C and 15 psi with H2SO4 concentrations at 5%, 10%, and 20%, obtaining an average of reducing sugars (pentoses and hexoses) from the hydrolyzed juice with 12.3%, 10%, and 17% Brix, respectively. The sugars were fermented using yeast of the Saccharomyces cerevisiae at 30C for 48 hours. Finally, the ethanol was distilled at 78C, and the average yields were obtained through analysis of variance with a 95% confidence level. The values indicate that there is a significant difference (p > 0.05), the Tukey study shows that all the % v/v averages are different from each other. For H2SO4 concentration at 5% (10.33 ± 2), H2SO4 at 10% (9.33 ± 1.8), and H2SO4 at 20% (6.33 ± 2). The acidity analysis for the ethanol obtained from each treatment gave a value of 1.8 mg/L of acetic acid in all cases. 展开更多
关键词 Lignocellulosic Ethanol Lignocellulosic Biomass Camalote grass Acid Hydrolysis Energy Crops
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Decoding the Genetic Blueprint of Grass Skyscrapers
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《Bulletin of the Chinese Academy of Sciences》 2024年第1期25-26,共2页
In the lush forests of Asia,towering bamboos stand tall,defying the folk expectations for grassy plants.These woody giants,some reaching the staggering height of nearly 40 meters,are the world’s largest members of th... In the lush forests of Asia,towering bamboos stand tall,defying the folk expectations for grassy plants.These woody giants,some reaching the staggering height of nearly 40 meters,are the world’s largest members of the grass family. 展开更多
关键词 family. grass grass
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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:1
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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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Dietary protein levels changed the hardness of muscle by acting on muscle fiber growth and the metabolism of collagen in sub-adult grass carp(Ctenopharyngodon idella) 被引量:1
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作者 Min Dong Lu Zhang +8 位作者 Pei Wu Lin Feng Weidan Jiang Yang Liu Shengyao Kuang Shuwei Li Haifeng Mi Ling Tang Xiaoqiu Zhou 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第2期729-744,共16页
Background:Nutrient regulation has been proven to be an effective way to improve the flesh quality in fish.As a necessary nutrient for fish growth,protein accounts for the highest proportion in the fish diet and is ex... Background:Nutrient regulation has been proven to be an effective way to improve the flesh quality in fish.As a necessary nutrient for fish growth,protein accounts for the highest proportion in the fish diet and is expensive.Although our team found that the effect of protein on the muscle hardness of grass carp was probably related to an increased collagen content,the mechanism for this effect has not been deeply explored.Moreover,few studies have explored the protein requirements of sub-adult grass crap(Ctenopharyngodon idella).Therefore,the effects of different dietary protein levels on the growth performance,nutritional value,muscle hardness,muscle fiber growth,collagen metabolism and related molecule expression in grass carp were investigated.Methods:A total of 450 healthy grass carp(721.16±1.98 g)were selected and assigned randomly to six experimen-tal groups with three replicates each(n=25/replicate),and were fed six diets with 15.91%,19.39%,22.10%,25.59%,28.53%and 31.42%protein for 60 d.Results:Appropriate levels of dietary protein increased the feed intake,percentage weight gain,specific growth rate,body composition,unsaturated fatty acid content in muscle,partial free amino acid content in muscle,and muscle hardness of grass carp.These protein levels also increased the muscle fiber density,the frequency of new muscle fibers,the contents of collagen and IGF-1,and the enzyme activities of prolyl 4-hydroxylases and lysyloxidase,and decreased the activity of matrix metalloproteinase-2.At the molecular level,the optimal dietary protein increased col-lagen type Iα1(Colα1),Colα2,PI3K,Akt,S6K1,La ribonucleoprotein domain family member 6a(LARP6a),TGF-β1,Smad2,Smad4,Smad3,tissue inhibitor of metalloproteinase-2,MyoD,Myf5,MyoG and MyHC relative mRNA levels.The levels of the myostatin-1 and myostatin-2 genes were downregulated,and the protein expression levels of p-Smad2,Smad2,Smad4,p-Akt,Akt,LARP6 and Smad3 were increased.Conclusions:The appropriate levels of dietary protein promoted the growth of sub-adult grass carp and improved muscle hardness by promoting the growth of muscle fibers,improving collagen synthesis and depressing collagen degradation.In addition,the dietary protein requirements of sub-adult grass carp were 26.21%and 24.85%according to the quadratic regression analysis of growth performance(SGR)and the muscle hardness(collagen content),respectively. 展开更多
关键词 Collagen degradation Collagen synthesis grass carp Muscle fibers Muscle hardness PROTEIN
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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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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 artificial grass tufting machine LMC20 CANopen bus touch screen panel servo system
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Mannan oligosaccharides alleviate oxidative injury in the head kidney and spleen in grass carp(Ctenopharyngodon idella)via the Nrf2 signaling pathway after Aeromonas hydrophila infection
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作者 Zhiyuan Lu Lin Feng +8 位作者 Weidan Jiang Pei Wu Yang Liu Jun Jiang Shengyao Kuang Ling Tang Shuwei Li Chengbo Zhong Xiaoqiu Zhou 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第4期1744-1758,共15页
Background Mannan oligosaccharides(MOS)are recommended as aquaculture additives owing to their excellent antioxidant properties.In the present study,we examined the effects of dietary MOS on the head kidney and spleen... Background Mannan oligosaccharides(MOS)are recommended as aquaculture additives owing to their excellent antioxidant properties.In the present study,we examined the effects of dietary MOS on the head kidney and spleen of grass carp(Ctenopharyngodon idella)with Aeromonas hydrophila infection.Methods A total of 540 grass carp were used for the study.They were administered six gradient dosages of the MOS diet(0,200,400,600,800,and 1,000 mg/kg)for 60 d.Subsequently,we performed a 14-day Aeromonas hydrophila challenge experiment.The antioxidant capacity of the head kidney and spleen were examined using spectrophotometry,DNA fragmentation,qRT-PCR,and Western blotting.Results After infection with Aeromonas hydrophila,400-600 mg/kg MOS supplementation decreased the levels of reactive oxygen species,protein carbonyl,and malonaldehyde and increased the levels of anti-superoxide anion,antihydroxyl radical,and glutathione in the head kidney and spleen of grass carp.The activities of copper-zinc superoxide dismutase,manganese superoxide dismutase,catalase,glutathione S-transferase,glutathione reductase,and glutathione peroxidase were also enhanced by supplementation with 400-600 mg/kg MOS.Furthermore,the expression of most antioxidant enzymes and their corresponding genes increased significantly with supplementation of 200-800 mg/kg MOS.mRNA and protein levels of nuclear factor erythroid 2-related factor 2 also increased following supplementation with 400-600 mg/kg MOS.In addition,supplementation with 400-600 mg/kg MOS reduced excessive apoptosis by inhibiting the death receptor pathway and mitochondrial pathway processes.Conclusions Based on the quadratic regression analysis of the above biomarkers(reactive oxygen species,malondialdehyde,and protein carbonyl)of oxidative damage in the head kidney and spleen of on-growing grass carp,the recommended MOS supplementation is 575.21,557.58,531.86,597.35,570.16,and 553.80 mg/kg,respectively.Collectively,MOS supplementation could alleviate oxidative injury in the head kidney and spleen of grass carp infected with Aeromonas hydrophila. 展开更多
关键词 ANTIOXIDANT Apoptosis Functional organs grass carp Mannan oligosaccharides
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Implications of vitamin D for flesh quality of grass carp(Ctenopharyngodon idella):antioxidant ability,nutritional value,sensory quality,and myofiber characteristics
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作者 Yao Zhang Chaonan Li +9 位作者 Xiaoqiu Zhou Weidan Jiang Pei Wu Yang Liu Hongmei Ren Lu Zhang Haifeng Mi Jiayong Tang Ruinan Zhang Lin Feng 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第6期2596-2613,共18页
Background Muscle represents a unique and complex system with many components and comprises the major edible part of animals.Vitamin D is a critical nutrient for animals and is known to enhance calcium absorption and ... Background Muscle represents a unique and complex system with many components and comprises the major edible part of animals.Vitamin D is a critical nutrient for animals and is known to enhance calcium absorption and immune response.In recent years,dietary vitamin D supplementation in livestock has received increased attention due to biological responses including improving shear force in mammalian meat.However,the vitamin D acquisition and myofiber development processes in fish differ from those in mammals,and the effect of vitamin D on fish flesh quality is poorly understood.Here,the influence of dietary vitamin D on fillet quality,antioxidant ability,and myofiber development was examined in grass carp(Ctenopharyngodon idella).Methods A total of 540 healthy grass carp,with an initial average body weight of 257.24±0.63 g,were allotted in 6 experimental groups with 3 replicates each,and respectively fed corresponding diets with 15.2,364.3,782.5,1,167.9,1,573.8,and 1,980.1 IU/kg vitamin D for 70 d.Results Supplementation with 1,167.9 IU/kg vitamin D significantly improved nutritional value and sensory quality of fillets,enhancing crude protein,free amino acid,lipid,and collagen contents;maintaining an ideal pH;and reduc-ing lactate content,shear force,and cooking loss relative to respective values in the control(15.2 IU/kg)group.Average myofiber diameter and the frequency of myofibers>50μm in diameter increased under supplementation with 782.5–1,167.9 IU/kg vitamin D.Levels of oxidative damage biomarkers decreased,and the expression of antioxi-dant enzymes and nuclear factor erythroid 2-related factor 2 signaling molecules was upregulated in the 1,167.9 IU/kg vitamin D treatment compared to respective values in the control group.Furthermore,vitamin D supplementation activated cell differentiation by enhancing the expression of myogenic regulatory factors and myocyte enhancer factors compared to that in the control group.In addition,supplementation with 1,167.9 IU/kg vitamin D improved protein deposition associated with protein synthesis molecule(target of rapamycin)signaling and vitamin D receptor paralogs,along with inhibition of protein degradation(forkhead box protein 1)signaling.Conclusions Overall,the results demonstrated that vitamin D strengthened antioxidant ability and myofiber devel-opment,thereby enhancing nutritional value and sensory quality of fish flesh.These findings suggest that dietary vitamin D supplementation is conducive to the production of nutrient-rich,high quality aquaculture products. 展开更多
关键词 ANTIOXIDANT grass carp Myofiber development Nutritional value Sensory quality Vitamin D
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Sporting Usefulness Potential of Nine Local Taxa of Grasses for Lawns in the Agro-Ecological Zone with Bimodal Rainfall in Cameroon
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作者 Meboma Zanga Yanique Lionel Godswill Ntsomboh Ntsefong +2 位作者 Temegne Nono Carine Tonfack Libert Brice Youmbi Emmanuel 《American Journal of Plant Sciences》 2023年第8期845-856,共9页
The Cameroonian flora has a very high biodiversity that remains largely unexplored. It contains many grasses that can be used for sports lawns, but are currently underutilized. In order to contribute to the improvemen... The Cameroonian flora has a very high biodiversity that remains largely unexplored. It contains many grasses that can be used for sports lawns, but are currently underutilized. In order to contribute to the improvement of the quality of sports lawns, nine local grass taxa from the agro-ecological zone with bimodal rainfall in Cameroon were evaluated for their potential for sporting use in natural lawns. The method of the Study and Control Group for Varieties and Seeds was used to evaluate the sports lawn characteristics of the taxa. The resistance to trampling and pulling, the density of the lawn, and the aesthetic appearance, which are factors in calculating the sports index, were monitored at two sites, including the experimental space at the University of Yaounde 1 in the Center region and Kagnol 2 in the East region, from January 2017 to January 2020. The monthly lawn characteristic data allowed for the differentiation between the means and the determination of the sports index of the taxa compared to commercialized lawn varieties. The sports index of the evaluated taxa varied: Cynodon dactylon (6.989), Eleusine indica (6.338), Sporobolus natalensis (6.301), Cynodon cf Cynodon dactylon (6.257), Eragrostis tremula (5.939), Sporobolus pyramidalis (5.583), Agrostis rupestris (5.335), Axonopus compressus (4.991), and Digitaria sp. (4.544). These results show that these grass taxa have potential for sporting use in lawn mixtures at different levels of sports disciplines. 展开更多
关键词 Sports Lawn Characteristics Sports Index Natural Sports Lawn Local grass Taxa Resistance to Trampling and Pulling
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The Destruction of Diasporic White Individuals’Sense of Identity in The Grass is Singing
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作者 LIU Rui 《Journal of Literature and Art Studies》 2023年第7期499-505,共7页
The importance of diaspora identity has grown in recent years as the world becomes more interconnected and diaspora individuals are increasingly involved in matters among different ethnics.The Grass is Singing by Dori... The importance of diaspora identity has grown in recent years as the world becomes more interconnected and diaspora individuals are increasingly involved in matters among different ethnics.The Grass is Singing by Doris Lessing is considered one of the most outstanding works of literature after World War II.Interest in ethnic identity has been heightened.The book is recognized as an introspective reflection of the spiritual crisis suffered by diaspora people and societal crises of the time.The thesis will examine the oppression imposed by dominant white group by exploring the transformation of diasporic white individuals’identity. 展开更多
关键词 Doris Lessing The grass is Singing diaspora identity societal oppression
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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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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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草业开源空间信息技术应用研究——以GRASS GIS处理地形图为例 被引量:1
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作者 郑逢令 储少林 +1 位作者 任玉平 赛里克.都曼 《草业科学》 CAS CSCD 北大核心 2010年第11期43-52,共10页
通过应用开源空间信息软件——地理资源分析支持系统(geohraphic resources analysis support system,GRASS)GIS软件处理地形图栅格数据的实践,简单介绍了GRASS GIS软件的基本情况,详细介绍了GRASS GIS开源软件中栅格数据输入,区域和坐... 通过应用开源空间信息软件——地理资源分析支持系统(geohraphic resources analysis support system,GRASS)GIS软件处理地形图栅格数据的实践,简单介绍了GRASS GIS软件的基本情况,详细介绍了GRASS GIS开源软件中栅格数据输入,区域和坐标系参数设置、栅格数据配准、投影变换、裁剪、数据输出等一系列操作,以事实证明开源技术能顺利完成草业领域中栅格数据的预处理。 展开更多
关键词 grass 开源空间信息 地形图
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不同树草共生体系下盐城地区桃园土壤改良效果及生态效应初探
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作者 林晶晶 王中军 颜振峰 《园艺与种苗》 CAS 2024年第2期27-29,共3页
[目的]筛选最适的桃园生草草种,以逐步提升桃园土壤地力,改善桃园生态环境,建设优质生态桃园。[方法]在盐城地区桃园开展以清耕和自然生草为对照,全园人工种植紫花苜蓿、紫云英、毛叶苕子、黑麦草、鼠茅草5种不同草种的田间试验,初步探... [目的]筛选最适的桃园生草草种,以逐步提升桃园土壤地力,改善桃园生态环境,建设优质生态桃园。[方法]在盐城地区桃园开展以清耕和自然生草为对照,全园人工种植紫花苜蓿、紫云英、毛叶苕子、黑麦草、鼠茅草5种不同草种的田间试验,初步探究不同树草共生体系下桃园土壤的改良效果和产生的生态效应。[结果]桃园生草能有效调节桃根际土壤p H,防控杂草滋生,改善桃园微环境,且不同树草共生体系影响效果不同。在生草的第3年尤以紫云英土壤p H改良效果最明显,但杂草抑制效果不明显,以毛叶苕子生草覆盖率和杂草抑制最优。[结论]该研究为盐城地区优质桃园的建设和生态环境建设提供了科学的理论支撑。 展开更多
关键词 生草 PH 树草共生体系 生态效应
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明代乡村慈善模式的制度设计和基层组织慈善功能的演变——以两湖地区为中心
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作者 周荣 《云南社会科学》 北大核心 2024年第1期147-157,共11页
在明初的乡村治理理念中,乡里制度是以里甲制为中心的综合多功能体,蕴含了丰富的社会管理、教化、治安等功能,也蕴含了巧妙的慈善功能。鳏寡孤独残疾有养、婚姻丧葬有助等慈善目标被融于官方的礼法体系和里甲编排等制度安排中。明中叶以... 在明初的乡村治理理念中,乡里制度是以里甲制为中心的综合多功能体,蕴含了丰富的社会管理、教化、治安等功能,也蕴含了巧妙的慈善功能。鳏寡孤独残疾有养、婚姻丧葬有助等慈善目标被融于官方的礼法体系和里甲编排等制度安排中。明中叶以后,社会分化加剧,里甲面临瓦解,部分职能废弛,有识之士在重整乡村秩序的过程中,借重的依然是明初的乡治理念。以乡约为中心的保甲、社仓等制度设计成为明代中后期基层治理和慈善救助的主要内容,保甲、乡约、社仓、社学“四合一”是明中后期理想的乡治模式。由于明代乡村治理中贯穿了精神与物质、慈善与控制相结合的原则,基层社会得以在较长时间中维持相对稳定的秩序。 展开更多
关键词 明代 乡村慈善 乡里制度 基层组织
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学生发展视角下地方本科院校基层院系发展型学生工作体系探索与实践
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作者 李秀英 周美艳 +2 位作者 陈罗庚 牟雅君 梁敏捷 《高教学刊》 2024年第13期152-155,共4页
新时代的发展对高校人才培养提出更高的要求,而学生工作作为高校人才培养的重要组成部分,对推动高校落实立德树人根本任务意义重大。院系学生工作是高校学生工作的基础和保障,构建科学合理的院系基层学生工作体系尤为重要。该文通过对... 新时代的发展对高校人才培养提出更高的要求,而学生工作作为高校人才培养的重要组成部分,对推动高校落实立德树人根本任务意义重大。院系学生工作是高校学生工作的基础和保障,构建科学合理的院系基层学生工作体系尤为重要。该文通过对玉林师范学院数学与统计学院学生工作内容进行系统的梳理、归纳和架构,探索“四航计划”和“十四大工程”为核心的发展型学生工作体系,以计划引领工程,以工程支撑计划,使得繁杂的学生工作变得规整、明确、清晰,形成“促进学生发展”的学生工作闭环,有效推进“三全育人”格局形成,努力培养符合新时代要求的高素质人才。 展开更多
关键词 学生发展 基层 学生工作体系 “四航计划” 人才培养
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Study on Plant Landscaping Methods in Garden Landscape Construction
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作者 Xiaohan WANG 《Asian Agricultural Research》 2024年第7期56-58,共3页
Garden landscape is a beautiful complex formed by space and time complementing each other and acting together.Garden plants are the core landscaping elements in garden landscape construction.It is necessary to flexibl... Garden landscape is a beautiful complex formed by space and time complementing each other and acting together.Garden plants are the core landscaping elements in garden landscape construction.It is necessary to flexibly use a variety of plant landscaping methods to create a richer and more vivid natural landscape,and promote the improvement of the quality of the living environment and the harmonious coexistence between man and nature. 展开更多
关键词 Garden landscape Plant landscaping Vertical greening Double-row and multi-row grass block paver
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