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The Technique of the Tri-Layer Coating: An Effective Solution for the Protection of Earthen Constructions
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作者 Sinko Banakinao Soviwadan Drovou +1 位作者 Komlan Lolo Kodjo Attipou 《Open Journal of Civil Engineering》 2023年第4期706-722,共17页
The problem with earth constructions is their low resistance to water. Step by step, the water degrades the exterior facings of the structures and ends up creating zones of weakness through the structures, making them... The problem with earth constructions is their low resistance to water. Step by step, the water degrades the exterior facings of the structures and ends up creating zones of weakness through the structures, making them collapse and creating enormous socio-economic problems, especially in rural areas. The solutions proposed to date, like the use of straw, cow dung, boiled skins, banana leaves, tar, cement soil, have shown their limits. Generally, the poor adhesion between the protected material and the protective layer means that the latter always ends up peeling off. This work, which is inspired by the traditional practice where plant tannins are used to brush the earthen walls to waterproof them, proposes a tri-layer coating composed of soil, powder and hydrolysable tannins extracted from the stem bark of Bridelia. This work focuses on the geotechnical characterization of the soil, the extraction of hydrolysable tannin, the manufacture of the micro-coating, the resistance tests carried out on the micro-coating, the technique of implementation and the test of evaluation of the performance of the tri-layer coating. The results obtained show that not only does the tri-layer coating adhere perfectly to the layer to protect, but it also waterproofs it and protects it against shocks. 展开更多
关键词 Tri-Layer TANNIN COATING Soil Earthen constructions
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On the Principal Constructions to Express the Future Time and Their Implications
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作者 朱虹 《海外英语》 2019年第13期256-257,共2页
According to the definition of tense,English has no actual future tense.The ways to express future time in English vary with the specific situation.We should avoid frequently using the same way to express the future.I... According to the definition of tense,English has no actual future tense.The ways to express future time in English vary with the specific situation.We should avoid frequently using the same way to express the future.It is important to study the different construction of the future time in English and its implications in order to make it clear that the appropriate construction to cope with the specific situation should be noticed. 展开更多
关键词 FUTURE constructions IMPLICATION of FUTURE constructions
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Constructions and Preliminary HV Conditioning of a Photocathode Direct-Current Electron Gun at IHEP 被引量:2
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作者 李小平 王九庆 +6 位作者 徐金强 裴士伦 肖欧正 何大勇 吕琨 孔祥成 彭晓华 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第7期56-60,共5页
As one of the most important key technologies for future advanced light source based on the energy recovery linac, a photocathode dc electron gun is supported by Institute of High Energy Physics (IHEP) to address th... As one of the most important key technologies for future advanced light source based on the energy recovery linac, a photocathode dc electron gun is supported by Institute of High Energy Physics (IHEP) to address the technical challenges of producing very low ernittance beams at high average current. Construction of the dc gun is completed and a preliminary high voltage conditioning is carried out up to 440 k V. The design, construction and preliminary HV conditioning results for the dc gun are described. 展开更多
关键词 ERL constructions and Preliminary HV Conditioning of a Photocathode Direct-Current Electron Gun at IHEP HV
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THE ECOLOGICAL FEATURES AND ECOLOGICAL CONSTRUCTIONS OF A MIRE IN CHINA
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作者 黄锡畴 《Chinese Geographical Science》 SCIE CSCD 1991年第1期56-63,共8页
A mire as an ecosystem, usually is considered as an aquatic ecosystem,or a terrestrial ecosystem. The author thinks that mire is a special ecosystem between these two ecosystems, and proposes the new concept that a mi... A mire as an ecosystem, usually is considered as an aquatic ecosystem,or a terrestrial ecosystem. The author thinks that mire is a special ecosystem between these two ecosystems, and proposes the new concept that a mire is a natural ecosystem with transitional nature of semi-water and semi-land formed by water and land interaction. The paper discusses the nature of the mire ecosystem, the exploitation and utilization and ecological construction of a mire. 展开更多
关键词 MIRE ECOSYSTEM nature of semi-water and semi- land ECOLOGICAL constructions
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Some Explicit Constructions of Type-Ⅱ,Ⅲ,Ⅳ,Ⅴ QC-LDPC Codes with Girth 6
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作者 Farzaneh Abedi Mohammad Gholami 《China Communications》 SCIE CSCD 2020年第5期89-109,共21页
Multi-type quasi-cyclic(QC) low-density parity-check(LDPC) codes can be considered as multiple-edge protograph QC-LDPC codes having some advantages in the minimum Hamming distance bound over single-edge protograph cod... Multi-type quasi-cyclic(QC) low-density parity-check(LDPC) codes can be considered as multiple-edge protograph QC-LDPC codes having some advantages in the minimum Hamming distance bound over single-edge protograph codes or type-Ⅰ QC-LDPC codes when the base matrices have the same size. In this paper, we investigate a class of multi-type QC-LDPC codes whose parity-check matrices contain just one blockrow of circulants and we obtain the generator matrix of such codes in general form. Using the permutation arrays and defining injection arrays, we present a new approach to construct a class of high-rate type-Ⅰ QC-LDPC codes with girth 6 from the constructed 4-cycle free multi-type QC-LDPC codes. In continue, for 2 ≤ w≤6, some type-w QC-LDPC codes with girth 6 are constructed explicitly such that the constructed codes are flexible in terms of rate and length. To the best of our knowledge, for w = 5,6, this is the first paper which deals with the explicit construction of type-w QC-LDPC codes with girth 6 and high rates. Moreover, for w = 3, 4, the constructed type-w QC-LDPC codes have better(6,8)-cycle multiplicities than the codes with minimum achievable length recently constructed by cyclic difference families(CDFs). Simulation results show that the binary and non-binary constructed codes outperform the constituent underlying QC-LDPC codes. 展开更多
关键词 QC-LDPC codes permutation arrays GIRTH explicit constructions
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Rehabilitation of Semi-mountainous Forest Area Using Bioclimatic Forest Constructions in Greece
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作者 Sarantis-Angelos Liampas Christos Stamatiou +3 位作者 Dimitris Farmakis Christodoulos Daoutis George Tasionas Vasileios Drosos 《Journal of Environmental Science and Engineering(A)》 2018年第2期82-88,共7页
Forest constructions are structures erected for serving the forest exploitation and utilization of its products,including recreation.The construction principals of a standard forest village with wooden lodgings apply ... Forest constructions are structures erected for serving the forest exploitation and utilization of its products,including recreation.The construction principals of a standard forest village with wooden lodgings apply principles of bioclimatic design and use ecological building materials.It highlights the area and helps to maintain the natural beauty of the forest.Accurate analysis of the area of the forest village requires the creation of topographic plan with great precision.Topographical drawing in AutoCAD in coordinate system HGRS’87 with contour interval 2 meters with the help of geodetic GPS was created.The aim of this paper was the rehabilitation of a semi-mountainous area taking into consideration environmental,economic,ergonomic and architectural constrains with the help of Google Earth.The area of the camp outside the village of Dadia of Evros Prefecture was granted by the army to the Forest Office of Soufli and remains unexploited until today.The installations were recorded and shown together with the topographic diagram and an image from Google Earth for the understudy-area.All the proposed facilities are presented in a Google Earth image and in a three-dimensional view.The forest village will be composed of 20 wooden lodges with a capacity of 4 persons each.The lodges will be designed around the bioclimatic design,in order to exercise the least impact on the natural environment and to meet the needs of residents for a comfortable and relaxed living.The landscaping was based on better utilization and lower environmental cost of construction in the landscape. 展开更多
关键词 FOREST constructions FOREST village GEODETIC GPS landscape Google Earth AutoCAD
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TWO NEW CONSTRUCTIONS OF CARTESIAN AUTHENTICATION CODES FROM SYMPLECTIC GEOMETRY 被引量:4
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作者 GAO YOU AND ZOU ZENGJIA (Department of Basic Science, Northeast Institute of Electric Power, Jinn 132012). 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1995年第3期345-356,共12页
In this paper, two new constructions of Cartesian authentication codes from symplectic geometry are presented and their size parameters are computed.
关键词 Cartesian authentication code construction symplectic geometry
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Chinese Liandong(Serial Verb) Constructions from the Perspective of Figure-Ground Relation
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作者 刘鹏 《海外英语》 2011年第1X期253-254,256,共3页
Empty categories,which lack phonological form and hence are not visible in the phonetic representation of the sentence,have both syntactic and semantic properties.Null subjects PRO and pro are base-generated empty cat... Empty categories,which lack phonological form and hence are not visible in the phonetic representation of the sentence,have both syntactic and semantic properties.Null subjects PRO and pro are base-generated empty categories.This thesis,based on Chomsky's theory about empty categories and research achievements made by Chinese scholars,attempts to analyze the liandong(Serial Verb) construction from Figure and Ground perspective. 展开更多
关键词 PRO Liandong(Serial) VERB construction FIGURE-GROUND
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Traffic organization during urban road constructions
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作者 宋丽英 《Journal of Beijing Institute of Technology》 EI CAS 2012年第2期216-221,共6页
This research presented a bi-level programming approach to optimize the schedule of ur- ban road construction activities based on a hypothetical transport network, with an objective of mini- mizing the overall traffic... This research presented a bi-level programming approach to optimize the schedule of ur- ban road construction activities based on a hypothetical transport network, with an objective of mini- mizing the overall traffic delays. A heuristic algorithm was utilized to identify a set of road construction schedules, while PARAMICS was adopted to estimate the total travel time in the network under each road construction scenario. To test the performance of proposed heuristics-simulation methodology, a numerical test was implemented. The overall results suggested that the proposed methodol- ogy could quickly find the optimum solution with good convergence. 展开更多
关键词 artificial intelligence microscopic traffic simulation road construction road network
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CONSTRUCTIONS OF THE GENERAL SOLUTION FOR A SYSTEM OF PARTIAL DIFFERENTIAL EQUATIONS WITH VARIABLE COEFFICIENTS
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作者 张鸿庆 杨光 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1991年第2期149-153,共5页
Solving partial differential equations Has not only theoretical significance, but also practical value. In this paper, by the property of conjugate operator, we give a method to construct the general solutions of a sy... Solving partial differential equations Has not only theoretical significance, but also practical value. In this paper, by the property of conjugate operator, we give a method to construct the general solutions of a system of partial differential equations. 展开更多
关键词 general solution noncommutative ring construction of solution conjugate operator
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Cyclic Shear Tests on Key Connection Joints of Modularized Constructions
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作者 Deshen Chen Xiaofei Jin +3 位作者 Huajie Wang Hongliang Qian Deci Chang Feng Fan 《Journal of Harbin Institute of Technology(New Series)》 CAS 2022年第3期13-20,共8页
Modularized construction is a new type of prefabricated building system with green environmental protection and excellent performance. There are few studies on the seismic performance of its key connection joint. This... Modularized construction is a new type of prefabricated building system with green environmental protection and excellent performance. There are few studies on the seismic performance of its key connection joint. This paper presents a new type of assembled connection joint for the high-rise modularized construction. Cyclic shear tests of full-scale joints were carried out, and the key indexes of their seismic performances including the hysteretic performance, ductility, and energy dissipation capacity were analyzed and obtained. The results show that the hysteresis loops of longitudinal and lateral cyclic shear tests were both plump in shapes. The ductility coefficients were 4.54 and 4.98, and the energy dissipation coefficients were 1.83 and 1.43, respectively. The test joint had good ductility and energy dissipation capacity. The positions of yield failure of specimens were mainly concentrated in the connection areas between the column and short beam or end-plate. The research can provide the technical reference for the seismic design and engineering application of related modularized constructions. 展开更多
关键词 modularized construction assembled connection joint cyclic shear test seismic performance
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Evaluation of Inverse Modeling Techniques for Pinpointing Water Leakages at Building Constructions
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作者 A. W. M. van Schijndel 《Modeling and Numerical Simulation of Material Science》 2015年第1期15-25,共11页
The location and nature of the moisture leakages are sometimes difficult to detect. Moreover, the relation between observed inside surface moisture patterns and where the moisture enters the construction is often not ... The location and nature of the moisture leakages are sometimes difficult to detect. Moreover, the relation between observed inside surface moisture patterns and where the moisture enters the construction is often not clear. The objective of this paper is to investigate inverse modeling techniques as a tool for the detection of moisture leakage locations in building constructions from inside surface moisture patterns. It is concluded that although the presented methodology is promising, more research is needed to confirm its usability. 展开更多
关键词 INVERSE MODELING BUILDING Construction MOISTURE LEAKAGE
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The Structure of Classifier Constructions and Some Related Theoretical Issues
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作者 Yang Yongzhong 《宏观语言学》 2021年第2期1-24,共24页
Some questions regarding the analysis of classifiers and classifier constructions are raised in this paper.The classifier,as a mere adjunct adjoining to the head,cannot serve as the head of the noun phrase containing ... Some questions regarding the analysis of classifiers and classifier constructions are raised in this paper.The classifier,as a mere adjunct adjoining to the head,cannot serve as the head of the noun phrase containing it,and as a result,it cannot project as ClP or nP.Under this approach,the DP analysis and the classifier construction theory are further refined.The constituents which precede and follow the classifier are analyzed in terms of their syntactic functions,semantic relations,linear features,feature assignment and syntactic occurrence in order to represent the classifier construction with the X-bar phrase structure theory appropriately and correctly and present a universal approach to classifier constructions in various languages. 展开更多
关键词 CLASSIFIER classifier construction HEAD phrase structure functional category
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Surface constructions of nano TiO_2 as the environmental and energy materials
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作者 LIN Chang-jian (State Key Laboratory of Physical Chemistry of Solid Surfaces,Xiamen University,Xiamen 361005,China) 《功能材料信息》 2007年第5期59-,共1页
TiO_2 has attracted an increasing attention because of its variety of potential applications in environments and energies,such as gas sensing,self-cleaning,solar energy conversion, wettability and photo-catalysis appl... TiO_2 has attracted an increasing attention because of its variety of potential applications in environments and energies,such as gas sensing,self-cleaning,solar energy conversion, wettability and photo-catalysis applications.In this presentation,we summarize some progress in surface constructions of nano TiO_2 and its characterizations of physicochemistry and properties. (1)Superhydrophobic nanostructure TiO_2 films Superhydrophobic nanotube,nanopore and sponge-like structure TiO_2 films are fabricated ... 展开更多
关键词 nano TiO2 surface construction physicochemistry properties
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Measurement of the Level of Knowledge of the Sands Used in Constructions in Togo
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作者 Ezoba Nayo Kossi Bollanigni Amey +1 位作者 Essé MawuléEdorh Komla Assogba Kassegne 《Journal of Minerals and Materials Characterization and Engineering》 2024年第4期225-235,共11页
Faced with the proliferation of quarries extracting silty sand and river sand used in the building and public works sector in Togo, recognition of the granular properties of these materials remains a major challenge f... Faced with the proliferation of quarries extracting silty sand and river sand used in the building and public works sector in Togo, recognition of the granular properties of these materials remains a major challenge for builders. This study aims to take stock of the use of sand in construction in Togo. One hundred and eighteen (118) sand quarries in operation, including thirty-eight (38) silty sand quarries and eighty (80) river sand quarries, were identified following surveys carried out among stakeholders involved in the chain of construction on 40% of the national territory. It appears from these surveys that river sands (59.43% to 84.68%) are prioritized over silty sands (15.32% to 40.57%). Three (3) main reasons are behind the choice of sand type;namely, proximity (28%), cleanliness (25%), good appearance (25%). These three (03) reasons partly explain the strong dependence of users on the sands located in their vicinity as well as the related expenses. Thus, making data available on the characteristics of sand, the materials most used in construction in Togo, would contribute to improving the housing conditions of the Togolese population. . 展开更多
关键词 Sands Togo Reasons for Use Construction
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Determining burn degree of fire-damaged concrete constructions by thermoluminescence 被引量:2
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作者 Pei, JX Han, Y Sun, XH 《Chinese Science Bulletin》 SCIE EI CAS 1997年第21期1829-1833,共5页
NOWADAYS there are many skyscrapers in cities. If fire-damaged, the only way to lessen
关键词 DETERMINING of thermolominescence CONCRETE constructions.
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基于Construct 3的射击类游戏设计与开发——以飞机大战为例
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作者 刘树林 杨艳瑜 李博 《微型电脑应用》 2024年第2期14-17,共4页
Construct 3作为小而精的H5跨平台游戏引擎,强大的交互性和用户友好性使其在2D游戏开发方面独具优势。借助Construct 3重构经典射击类游戏“飞机大战”,通过Event Sheet实现游戏中背景循环滚动、动画导入、角色创建与随机运动、游戏难... Construct 3作为小而精的H5跨平台游戏引擎,强大的交互性和用户友好性使其在2D游戏开发方面独具优势。借助Construct 3重构经典射击类游戏“飞机大战”,通过Event Sheet实现游戏中背景循环滚动、动画导入、角色创建与随机运动、游戏难度控制、游戏变量控制等主要功能。经过测试,游戏可打包发布成Web、移动设备和PC端.exe格式,游戏交互、特效运行流畅,游戏变量与难度控制处于合理范围。 展开更多
关键词 Construct 3 游戏开发 射击类游戏
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Evaluating the performance of genomic selection on purebred population by incorporating crossbred data in pigs
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作者 Jun Zhou Qing Lin +10 位作者 Xueyan Feng Duanyang Ren Jinyan Teng Xibo Wu Dan Wu Xiaoke Zhang Xiaolong Yuan Zanmou Chen Jiaqi Li Zhe Zhang Hao Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期639-648,共10页
Genomic selection(GS)has been widely used in livestock,which greatly accelerated the genetic progress of complex traits.The population size was one of the significant factors affecting the prediction accuracy,while it... Genomic selection(GS)has been widely used in livestock,which greatly accelerated the genetic progress of complex traits.The population size was one of the significant factors affecting the prediction accuracy,while it was limited by the purebred population.Compared to directly combining two uncorrelated purebred populations to extend the reference population size,it might be more meaningful to incorporate the correlated crossbreds into reference population for genomic prediction.In this study,we simulated purebred offspring(PAS and PBS)and crossbred offspring(CAB)base on real genotype data of two base purebred populations(PA and PB),to evaluate the performance of genomic selection on purebred while incorporating crossbred information.The results showed that selecting key crossbred individuals via maximizing the expected genetic relationship(REL)was better than the other methods(individuals closet or farthest to the purebred population,CP/FP)in term of the prediction accuracy.Furthermore,the prediction accuracy of reference populations combining PA and CAB was significantly better only based on PA,which was similar to combine PA and PAS.Moreover,the rank correlation between the multiple of the increased relationship(MIR)and reliability improvement was 0.60-0.70.But for individuals with low correlation(Cor(Pi,PA or B),the reliability improvement was significantly lower than other individuals.Our findings suggested that incorporating crossbred into purebred population could improve the performance of genetic prediction compared with using the purebred population only.The genetic relationship between purebred and crossbred population is a key factor determining the increased reliability while incorporating crossbred population in the genomic prediction on pure bred individuals. 展开更多
关键词 PIGS crossbred population genomic selection reference population construction relationship
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Promoting grain production through high-standard farmland construction:Evidence in China
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作者 Shuai Hao Guogang Wang +4 位作者 Yantao Yang Sicheng Zhao Shengnan Huang Liping Liu Huanhuan Zhang 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期324-335,共12页
Food security is a strategic priority for a country’s economic development.In China,high-standard farmland construction(HSFC)is an important initiative to stabilize grain production and increase grain production capa... Food security is a strategic priority for a country’s economic development.In China,high-standard farmland construction(HSFC)is an important initiative to stabilize grain production and increase grain production capacity.Based on panel data from 31 sample provinces,autonomous regions,and municipalities in China from 2005–2017,this study explored the impact of HSFC on grain yield using the difference-in-differences(DID)method.The results showed that HSFC significantly increased total grain production,which is robust to various checks.HSFC increased grain yield through three potential mechanisms.First,it could increase the grain replanting index.Second,it could effectively reduce yield loss due to droughts and floods.Last,HSFC could strengthen the cultivated land by renovating the low-and medium-yielding fields.Heterogeneity analysis found that the HSFC farmland showed a significant increase in grain yield only in the main grain-producing areas and balanced areas.In addition,HSFC significantly increased the yields of rice,wheat,and maize while leading to a reduction in soybean yields.The findings suggest the government should continue to promote HSFC,improve construction standards,and strictly control the“non-agriculturalization”and“non-coordination”of farmland to increase grain production further.At the same time,market mechanisms should be used to incentivize soybean farming,improve returns and stabilize soybean yields. 展开更多
关键词 high-standard farmland farmland construction food security food production area DIFFERENCE-IN-DIFFERENCES
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Impacts of hydropower-induced flow alterations on composition and diversity of riparian vegetation in the Western Himalayas: A case study in Uttarakhand, India
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作者 Dharmveer KAINTURA Sabyasachi DASGUPTA Dhanpal Singh CHAUHAN 《Journal of Mountain Science》 SCIE CSCD 2024年第4期1272-1286,共15页
The increasing demand for water and energy resources has led to widespread dam construction,particularly in ecologically sensitive regions like the Himalayan Range.This study focuses on the Uttarakhand state in the We... The increasing demand for water and energy resources has led to widespread dam construction,particularly in ecologically sensitive regions like the Himalayan Range.This study focuses on the Uttarakhand state in the Western Himalayas,where hydroelectric projects(HEPs)have significantly altered river flow regimes.The research investigates the impact of flow alterations on the composition and structure of riparian vegetation in the Garhwal Himalayas,specifically analysing four rivers regulated by hydroelectric projects.Utilizing the paired-reach comparison method,control(undisturbed),diverted(downstream of barrage/dam),and altered flow conditions(downstream of water outlet)were examined.The research reveals diverse and unique riparian ecosystems,with 89 genera and 113 taxa identified,showcasing the dominance of families like Asteraceae and Lamiaceae.The study unveils the structural importance of key species such as Berberis asiatica and Artemisia nilagirica.The density,diversity,and richness of shrub and herb species vary significantly across flow conditions.Notably,altered flow conditions demonstrate resilience in vegetation structure,while diverted conditions exhibit decreased species richness and density.The study emphasizes the importance of nuanced environmental flow management for mitigating adverse effects on riparian biodiversity in the fragile Himalayan region.These findings contribute to the global discourse on dam impacts and riparian ecology,shedding light on the complexities of this dynamic relationship in a vulnerable ecosystem. 展开更多
关键词 Dam construction Water stress Western Himalayas Disturbed flow regimes Riparian ecosystem
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