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基于垂直带谱的南北过渡带1:5万植被类型图遥感制图研究——以太白山为例 认领
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作者 姚永慧 索南东主 张俊瑶 《地理学报:英文版》 SCIE CSCD 2020年第2期267-280,共14页
The compilation of 1:250,000 vegetation type map in the North-South transitional zone and 1:50,000 vegetation type maps in typical mountainous areas is one of the main tasks of Integrated Scientific Investigation of t... The compilation of 1:250,000 vegetation type map in the North-South transitional zone and 1:50,000 vegetation type maps in typical mountainous areas is one of the main tasks of Integrated Scientific Investigation of the North-South Transitional Zone of China.In the past,vegetation type maps were compiled by a large number of ground field surveys.Although the field survey method is accurate,it is not only time-consuming,but also only covers a small area due to the limitations of physical environment conditions.Remote sensing data can make up for the limitation of field survey because of its full coverage.However,there are still some difficulties and bottlenecks in the extraction of remote sensing information of vegetation types,especially in the automatic extraction.As an example of the compilation of 1:50,000 vegetation type map,this paper explores and studies the remote sensing extraction and mapping methods of vegetation type with medium and large scales based on mountain altitudinal belts of Taibai Mountain,using multi-temporal high resolution remote sensing data,ground survey data,previous vegetation type map and forest survey data.The results show that:1)mountain altitudinal belts can effectively support remote sensing classification and mapping of 1:50,000 vegetation type map in mountain areas.Terrain constraint factors with mountain altitudinal belt information can be generated by mountain altitudinal belts and 1:10,000 Digital Surface Model(DSM)data of Taibai Mountain.Combining the terrain constraint factors with multi-temporal and high-resolution remote sensing data,ground survey data and previous small-scale vegetation type map data,the vegetation types at all levels can be extracted effectively.2)The basic remote sensing interpretation and mapping process for typical mountains is interpretation of vegetation type-groups→interpretation of vegetation formation groups,formations and subformations→interpretation and classification of vegetation types&subtypes,which is a combination method of top-down m 展开更多
关键词 vegetation type map high resolution REMOTE SENSING data MOUNTAIN altitudinal BELTS REMOTE SENSING interpretation Taibai MOUNTAIN
The Field Shielding Effect of Mountain on the Lightning Electromagnetic Field 认领
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作者 Xiaoyu Peng Lei Wang +2 位作者 Jinbo Zhang Jiawen Chen Bingzhe Dai 《电磁分析与应用期刊(英文)》 2020年第2期15-28,共14页
In this paper we have studied the effect of strike to a cone-shaped mountain surrounded by two chains of hills on the lightning vertical electric field and azimuthal magnetic field at different distances, by using two... In this paper we have studied the effect of strike to a cone-shaped mountain surrounded by two chains of hills on the lightning vertical electric field and azimuthal magnetic field at different distances, by using two-dimensional finite-difference time-domain (2-D FDTD) method in cylindrical coordinate systems. In order to analyze the electrostatic shielding effect of strike to a cone-shaped mountain surrounded by two chains of hills on the lightning, we chose three mountains, and the left one is stroke by lightning, and the right one is near the obervation site, and the middle one with the top heights increasing from 0 to 2 km is between them. For the observed point, the electrostatic shielding effect of the right one on the lightning vertical electric field is the most serious, and the electric field is much less than that for strike to flat ground level;compared with the electric field, the shielding effect of the right one on the lightning azimuthal magnetic field becomes less, for most cases, the lightning magnetic field at the observed site is larger than that for flat ground cases mainly due to that of the increment caused by strike to the right mountain. With the increase of distance (e.g., 20 km from the lightning strike point), the shielding effect of the right mountain on the lightning field becomes less, because the reflected wave from the right mountain bottom plays a more important role over intermediate ranges, and the far radiation electromagnetic field peak value becomes larger due to such a reflecting wave. Therefore, in the lightning detecting technique, we should pay more attention to the effect caused by chains of hills on the lightning location and the estimation of lightning current peak. 展开更多
关键词 LIGHTNING Current LIGHTNING Electromagnetic MOUNTAIN HEIGHT MOUNTAIN INCLINATION PROPAGATION PATH
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Existence of Infinitely Many High Energy Solutions for a Fourth-Order Kirchhoff Type Elliptic Equation in R<sup>3</sup> 认领
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作者 Qiongfen Zhang 《应用数学与应用物理(英文)》 2020年第8期1550-1559,共10页
In this paper, we consider the following fourth-order equation of Kirchhoff type<br /> <p> <img src="Edit_bcc9844d-7cbc-494d-90c4-d75364de5658.bmp" alt="" /> </p> <p> ... In this paper, we consider the following fourth-order equation of Kirchhoff type<br /> <p> <img src="Edit_bcc9844d-7cbc-494d-90c4-d75364de5658.bmp" alt="" /> </p> <p> where <i>a</i>, <i>b</i> > 0 are constants, 3 < <i>p</i> < 5, <i>V</i> ∈ <i>C</i> (R<sup>3</sup>, R);Δ<sup>2</sup>: = Δ (Δ) is the biharmonic operator. By using Symmetric Mountain Pass Theorem and variational methods, we prove that the above equation admits infinitely many high energy solutions under some sufficient assumptions on <i>V</i> (<i>x</i>). We make some assumptions on the potential <i>V</i> (<i>x</i>) to solve the difficulty of lack of compactness of the Sobolev embedding. Our results improve some related results in the literature. </p> 展开更多
关键词 Fourth-Order Kirchhoff Type Elliptic Equation Infinitely Many Solutions Symmetric Mountain Pass Theorem Variational Methods
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Regional- to local-scale controls on waterfalls in Rocky Mountain National Park,Colorado 认领
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作者 Jose A.ORTEGA-BECERRIL Bridget LIVERS Ellen WOHL 《山地科学学报:英文版》 SCIE CSCD 2020年第8期1874-1890,共17页
Previous work on the eastern side of Rocky Mountain National Park(RMNP),Colorado indicated correlations among waterfall location,waterfall morphology,and the characteristics of bedrock joints.Characteristics of waterf... Previous work on the eastern side of Rocky Mountain National Park(RMNP),Colorado indicated correlations among waterfall location,waterfall morphology,and the characteristics of bedrock joints.Characteristics of waterfalls on the western side of the national park do not correlate as strongly with joint geometry.Longitudinal river profiles on the western side are less concave and waterfalls account for a greater proportion of the total elevation loss.We interpret these differences to result from more widely spaced joints,lithological differences,and complex glacial history.These results demonstrate that waterfall shape and typology may change due to both local and regional controls operating in a mountain region.Both regions had alpine valley glaciers,but continued landscape evolution via fluvial erosion has developed waterfalls with diverse locations and morphologies that reflect the influences of glacial deposits,bedrock erosional resistance,and joint geometry. 展开更多
关键词 WATERFALL Rocky Mountain National Park KNICKPOINT BEDROCK Mountain stream regional-scale controls
Altitude-dependent distribution of 137Cs in the environment:a case study of Aragats massif,Armenia 认领
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作者 Konstantin Pyuskyulyan Stephen P.LaMont +3 位作者 Vovik Atoyan Olga Belyaeva Nona Movsisyan Armen Saghatelyan 《中国地球化学学报:英文版》 EI CAS CSCD 2020年第1期127-138,共12页
This paper considers the distribution of technogenic 137Cs and naturally occurring radionuclides:238 U,232 Th and40 R concentrations in soils and 137Cs in atmospheric dry depositions by altitudinal belts of the Aragat... This paper considers the distribution of technogenic 137Cs and naturally occurring radionuclides:238 U,232 Th and40 R concentrations in soils and 137Cs in atmospheric dry depositions by altitudinal belts of the Aragats mountain massif,Republic of Armenia.Undisturbed soil samples were collected at altitudes from 1000 to 3200 m.For the determination of geochemical variability,two soil sampling campaigns were undertaken.Atmospheric dry depositions were sampled from five stations at1100-3200 m collected onto organic fiber filters between June and December 2016.137Cs activity was measured using a high-purity Germanium detector coupled to a multichannel analyzer(Canberra).Results indicated that specific activity of 137Cs in soils at 1000 m is495-528 Bq m^-2,andat3200 mis10,500-11,470 Bq m^-2.No correlation observed for 137Cs versus naturally occurring radionuclides,which varies in distribution by altitude.Specific activities of 137Cs in dry atmospheric depositions varies from 1.06 at 846 m to2.37 Bq m^-2 per quarter at 3200 m and increases as the altitude increases.Activities of 137Cs in soil and dry atmospheric deposition correlated significantly,and 137Cs activity in soils and atmospheric dry depositions decrease as the absolute altitude decreases.The 50-year effective dose from exposure to 137Cs fallout varies with altitude from 0.007 to 1.42 m Sv. 展开更多
关键词 137Cs DISTRIBUTION by ALTITUDE Naturally occurring radionuclides TOPSOIL Dry atmospheric depositions Gamma radiation Mountain regions
Survey of Ecotourism Landscape Resources and Shrub Landscape Resources in Western Sichuan Mountains 认领
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作者 YU Qiannan PENG Yong +4 位作者 LIU Zheng LI Ting HU Jun HUANG Tao LIU Qing 《景观研究:英文版》 2020年第5期26-33,共8页
As a high-end tourism activity advocating back to nature and protecting the nature,ecotourism has won increasing attention in recent years home and abroad.Being endowed with outstanding topographical and natural lands... As a high-end tourism activity advocating back to nature and protecting the nature,ecotourism has won increasing attention in recent years home and abroad.Being endowed with outstanding topographical and natural landscape resources,Sichuan has been a major ecotourism province in China.Particularly,western Sichuan mountains is more scarcely populated area with great topographical fluctuations,thus it is more suitable for developing ecotourism activities than eastern Sichuan.Based on previous researches and statistical analysis,this paper reviewed the overall situation of ecotourism landscape resources in western Sichuan mountains,including its geomorphological landforms,hydrographic landscapes,biological landscapes,meteorological and climatic landscapes.More importantly,in view of the blank area found in the statistical analysis,the paper analyzed the shrub landscapes on the basis of fi eld investigation,to support further research on the development and utilization of local ecotourism resources. 展开更多
关键词 ECOTOURISM Landscape resources Shrub landscape Mountain Western Sichuan
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Gorilla Thriller More Chinese tourists keen to encounter mountain gorillas 认领
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作者 Godfrey Olukya 《中国与非洲:英文版》 2020年第8期36-37,共2页
The majestic mountain gorilla has a very secluded home,living exclusively in the tropical forests of the Democratic Republic of the Congo(DRC),Rwanda and Uganda.According to the World Wildlife Fund for Nature(WWF),the... The majestic mountain gorilla has a very secluded home,living exclusively in the tropical forests of the Democratic Republic of the Congo(DRC),Rwanda and Uganda.According to the World Wildlife Fund for Nature(WWF),there are more than 1,000 mountain goril las living in the world,less than a half of which live in the Virunga Mountains on the border of the DRC and Rwanda,with the remainder calling tlie Bwindi Impeneti able National Park in Uganda home. 展开更多
关键词 MOUNTAIN RILL TOURIST
安全保障视角的山地户外旅游报警装备的研制 认领
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作者 栗长春 《粘接》 CAS 2020年第2期170-173,共4页
在现代社会经济不断发展的过程中,我国旅游业也在不断发展。但是目前旅游环境问题越来越严重,为了避免出现旅游安全问题,就对基于安全保障视角中的山地户外旅游报警装备进行分析,介绍系统工作原理及电路的设计。在旅游地点中使用报警系... 在现代社会经济不断发展的过程中,我国旅游业也在不断发展。但是目前旅游环境问题越来越严重,为了避免出现旅游安全问题,就对基于安全保障视角中的山地户外旅游报警装备进行分析,介绍系统工作原理及电路的设计。在旅游地点中使用报警系统方案,只要其中一个旅游地点报警,那么报警控制中心就能够接收报警信号,利用报警区域显示器将数据进行显示,从而对报警区域进行确定。 展开更多
关键词 安全保障 山地 户外旅游 报警装置
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山脉对于风电场影响的计算分析 认领
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作者 韩晓亮 高志鹰 《电网与清洁能源》 2020年第8期112-115,共4页
针对内蒙古区域典型风电场,采用专业软件Wasp计算分析了山脉对于风电场发电量的影响,通过假设山脉有无的方式对比分析了与山脉不同距离时,发电量减少的相对差值与距离、高度的关系,通过对比分析得出以下结论:山脉对于周围风电场的发电... 针对内蒙古区域典型风电场,采用专业软件Wasp计算分析了山脉对于风电场发电量的影响,通过假设山脉有无的方式对比分析了与山脉不同距离时,发电量减少的相对差值与距离、高度的关系,通过对比分析得出以下结论:山脉对于周围风电场的发电量有影响;随着风电场距离山脉越远,山脉对于风电场发电量的影响逐渐降低,与山脉距离由0 km至1 km时,发电量减少的相对差值幅度最大;山脉的高度越高,其对风电场的影响越大,对于所研究的区域,主峰区域的风电场发电量减小相对差值是中段区域的风电场发电量减小相对差值的1.5倍左右。 展开更多
关键词 山脉 尾流模型 风电场
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山地乡村聚集式新民居设计探讨 认领
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作者 罗卿平 高佳妮 陈蕙如 《建筑与文化》 2020年第7期266-267,共2页
山地乡村新民居建设往往存在环境破坏严重、设计形式单一、建造难度大等问题,基于此背景,文章展开对山地乡村聚集式新民居设计新思路的探讨。文章以真实项目基地为载体,提出山地乡村新民居设计既要与自然地形地貌有机结合,节约用地,最... 山地乡村新民居建设往往存在环境破坏严重、设计形式单一、建造难度大等问题,基于此背景,文章展开对山地乡村聚集式新民居设计新思路的探讨。文章以真实项目基地为载体,提出山地乡村新民居设计既要与自然地形地貌有机结合,节约用地,最大限度保护生态环境;在实现高效及可推广性设计建造的同时,保证村落形象的多样和自由;还应具有乡村风貌特色,能够引领乡村高品质生活生产新方式。 展开更多
关键词 乡村 山地 聚集式新民居 模块化
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热刺法对皮肤局部温度的影响:一项临床研究 认领
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作者 廖泽寰 赵雁 《世界针灸杂志:英文版》 CSCD 2020年第3期202-206,共5页
Objective:This clinical study was performed to examine the influence of heat-producing acupuncture(HPA)treatment on the local skin temperature of Zusanli(足三里ST36)acupoint in healthy participants.Methods:30 healthy ... Objective:This clinical study was performed to examine the influence of heat-producing acupuncture(HPA)treatment on the local skin temperature of Zusanli(足三里ST36)acupoint in healthy participants.Methods:30 healthy participants received four successive sessions of heat-producing acupuncture(HPA),non-acupoint HPA(NAHPA),normal stable acupuncture(Norm)and non-invasive sham acupuncture(Sham)on the ST36 acupoint in random order.Within each treatment session,the local skin temperature of ST36 acupoint and basal body temperature of each participant were measured at 1 min before needle insertion(T1 B),just after needle insertion and manipulation(T0),5 min after needle insertion(T5)and 5 min after needle removal(T5 A).Visual Analogue Scale(VAS)scores of the participants’perceived needling and heat sensation felt during the acupuncture treatment period(T0-T5)were also recorded on a scale of 1 to 10.Results:Intra-session group statistical analyses of the different time points in the HPA treatment session group demonstrates that ST36 local skin temperature remained relatively stable between T1 B and T0,increased significantly between T0 and T5 and decreased significantly between T5 and T5 A.For intersession group statistical analysis of all treatment session groups,the increase in local skin temperature of ST36 acupoint between T0 and T5 in the HPA treatment session group was significantly higher than those of the NAHPA treatment session group(P<0.01),Norm treatment session group(P<0.01)and Sham treatment session group(P<0.01).The decrease in local skin temperature of ST36 acupoint between T5 and T5 A in the HPA treatment session group was also significantly more than those of NAHPA treatment session group(P<0.05),Norm treatment session group(P<0.01)and Sham treatment session group(P<0.001).Conclusion:Our study provides evidence that HPA treatment performed significantly better than the other three treatments in elevating the local skin temperature of ST36 acupoint temporarily.Our results also align with those of man 展开更多
关键词 ACUPUNCTURE Shaoshanhuo Heat-producing needling Setting fire on the mountain Traditional Chinese medicine Local skin temperature Nitric oxide
山地果园管道喷雾技术及植保机械研究进展 认领
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作者 李昕昊 王鹏飞 《现代农业科技》 2020年第13期147-149,共3页
我国作为世界最大的水果出产国,果品质量影响着水果产业的发展,而喷施农药是保证果品质量、减少病虫害的有效途径。但是,作为适宜水果种植的丘陵山地地区的果园植保机械化水平低。因此,发展适宜的果园植保机械才能促进我国水果产业的长... 我国作为世界最大的水果出产国,果品质量影响着水果产业的发展,而喷施农药是保证果品质量、减少病虫害的有效途径。但是,作为适宜水果种植的丘陵山地地区的果园植保机械化水平低。因此,发展适宜的果园植保机械才能促进我国水果产业的长期良性发展。本文简要介绍了目前我国适用于山地果园植保的管道喷雾设备、小型喷雾机、电动遥控喷雾技术、轨道搭载风送式喷雾机以及无人机喷雾技术,以期为促进山地果园的发展提供参考。 展开更多
关键词 果园 管道喷雾 植保机械 山地
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Low-energy Mountain Transportation System with PRT Rail Transit Technology 认领
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作者 SUN Shuai WANG Biao 《景观研究:英文版》 2020年第3期15-17,26,共4页
The PRT (Personal Rapid Transit) refers to a traffic system in which small vehicles automatically travel on a dedicated rail network or road network.It is a branch of monorail traffic and dedicated road traffic.It can... The PRT (Personal Rapid Transit) refers to a traffic system in which small vehicles automatically travel on a dedicated rail network or road network.It is a branch of monorail traffic and dedicated road traffic.It can change the situation of high energy consumption of traditional mountain transportation.It can reduce the amount of machinery used in the construction process to reduce carbon emissions.It is completely powered by electricity and reduces the friction of the cableway to reduce energy consumption.Its construction process uses small amount of traditional building materials such as concrete and steel.It has little damage to the ecological environment of the mountain,and can not damage the carbon sequestration ability of the plant community.It could serve as a means of transporting goods over long distance,reducing the need for big trucks and thus reducing the consumption of fossil fuels. 展开更多
关键词 PRT transportation system Mountain area Low energy consumption
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Types of uranium deposits in central Zhuguang Mountains in Hunan Province,South China and their metallogenic regularity and prospecting directions 认领
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作者 Zhen-hua Xiao Shen-bang Xiong +4 位作者 Chun-hua Li Ying Liu Zhong-ding Yang Xiao-xi Feng Xue-wen Liu 《中国地质(英文)》 2020年第3期411-424,共14页
The central Zhuguang Mountains in Hunan Province is located at the junction of the three provinces,namely Hunan,Jiangxi,and Guangdong,where the famous Lujing uranium ore field lies.The uranium deposits occurring in th... The central Zhuguang Mountains in Hunan Province is located at the junction of the three provinces,namely Hunan,Jiangxi,and Guangdong,where the famous Lujing uranium ore field lies.The uranium deposits occurring in this area are all granite-related and they can be divided into three types,namely endogranitic ones,perigranitic ones,and contact zone types.The endogranitic uranium deposits are mainly controlled by the structural alteration zones developing within granites,with fragmentation,hematitization,and alkali metasomatism as their main mineralization characteristics.The perigranitic uranium deposits are mainly produced in the carbonaceous,siliceous,and argillaceous composite layers of epimetamorphic rocks and are controlled by fractured zones formed due to interlayer compression.The contact zone type uranium deposits mainly occur in the contact parts between the granites and favorable horizons.They have developed in favorable sections where multiple sets of structures are combined and intersected.The main metallogenic regularities of uranium in the central Zhuguang Mountains are as follows.The basic conditions for the uranium mineralization in this area include the framework consisting of regional deep large faults and their associated multi-set multi-direction favorable metallogenic structures,multi-cycle and multi-stage uranium-rich rock masses,and uranium-rich folded basement.Meanwhile,the uranium deposits in this area are closely related to granites in terms of genesis and space and they are formed in different structural parts subject to the same metallization.Furthermore,based on the summary of the characteristics and regularities of uranium mineralization in this area,the controlling factors of different types of uranium deposits in the area were explored and six metallogenic target areas were predicted.All these will provide references for the exploration of uranium deposits in this area. 展开更多
关键词 Uranium deposits Magmatic hydrothermal type Metallogenic regularity Mineral exploration engineering Prospecting direction Zhuguang Mountain Hunan Province South China
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贵州山地芒果嫁接育苗关键技术 认领
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作者 张正学 刘清国 +3 位作者 刘荣 李向勇 谢忠武 赵久云 《贵州农业科学》 CAS 2020年第4期115-118,共4页
为贵州芒果产业发展提供指导参考,根据贵州低热河谷的自然条件,研究不同嫁接方法、品种接穗、嫁接时间、成熟度接穗、接穗长度对嫁接成活率的影响。结果表明:嫁接方法为切接、接穗品种为金煌芒、嫁接时间在5月1日左右、当年生木质化绿... 为贵州芒果产业发展提供指导参考,根据贵州低热河谷的自然条件,研究不同嫁接方法、品种接穗、嫁接时间、成熟度接穗、接穗长度对嫁接成活率的影响。结果表明:嫁接方法为切接、接穗品种为金煌芒、嫁接时间在5月1日左右、当年生木质化绿色春枝及接穗长度在3~5cm(2~3芽)的芒果嫁接成活率均最高,分别为97.0%、94.3%、94.3%、94.3%和95.7%。贵州芒果嫁接相关环节的技术指标可参考该研究结果在生产上应用。 展开更多
关键词 芒果 育苗 技术 山地 贵州
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Promoting the Construction of Beautiful and Rich China with the Theory of Soil and Water Ecology 认领
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作者 Fazheng SUN 《气象与环境研究:英文版》 CAS 2020年第2期20-24,共5页
Started from the problems and perplexities of ecological environment in China,the scientific principle and value of the theory of soil and water ecology are discussed. It is thought that the theory of soil and water e... Started from the problems and perplexities of ecological environment in China,the scientific principle and value of the theory of soil and water ecology are discussed. It is thought that the theory of soil and water ecology clarifies the complicated problems of ecological environment. Environmental pollution can be controlled,but it is only a matter of time and cost. Soil and water ecology is the root of ecological environment problems. The clean water and green mountain are destroyed,which cannot be restored. With the theory of soil and water ecology,the idea that clean water and green mountain are golden and silver mountains is read,as well as the way of turning clean water and green mountain into golden and silver mountains and its different impacts on eco-environment. The developed and underdeveloped areas should treat the idea that clean water and green mountain are golden and silver mountains. The application of the theory of soil and water ecology in soil and water conservation broadens the space of soil and water conservation,and it is necessary to establish a national commission for the conservation of soil and water ecology. The theory of soil and water ecology is the golden key to solve the problems of contemporary ecological environment and the theoretical basis for building a beautiful and rich China. 展开更多
关键词 Ecological environment SOIL and WATER ecology Clean WATER and green mountain GOLDEN and silver MOUNTAINS BEAUTIFUL and RICH
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山区某隧道的岩土工程分析 认领
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作者 罗均宇 《山西建筑》 2020年第21期123-125,共3页
通过工程实例对山区隧道穿越段的岩土层调查,查明工作区范围地层岩性、岩层产状、构造及不良地质对隧道通过的影响程度,分析隧道所穿越的岩土层的隧道围岩类别,为隧道穿越工程初步设计提供所需的相关工程地质依据和工程设计所需的岩土... 通过工程实例对山区隧道穿越段的岩土层调查,查明工作区范围地层岩性、岩层产状、构造及不良地质对隧道通过的影响程度,分析隧道所穿越的岩土层的隧道围岩类别,为隧道穿越工程初步设计提供所需的相关工程地质依据和工程设计所需的岩土工程参数等,对山区隧道的设计施工具有一定的借鉴作用。 展开更多
关键词 山区 工程地质 隧道 隧道围岩
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Mountain tunnel under earthquake force:A review of possible causes of damages and restoration methods 认领
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作者 Xuepeng Zhang Yujing Jiang Kazuhiko Maegawa 《岩石力学与岩土工程学报:英文版》 SCIE CSCD 2020年第2期414-426,共13页
Accurate seismic assessment and proper aseismic design of underground structures require a comprehensive understanding of seismic performance and response of underground structures under earthquake force.In order to u... Accurate seismic assessment and proper aseismic design of underground structures require a comprehensive understanding of seismic performance and response of underground structures under earthquake force.In order to understand the seismic behavior of tunnels during an earthquake,a wide collection of case histories has been reviewed from the available literature with respect to damage classification,to discuss the possible causes of damage,such as earthquake parameters,structural form and geological conditions.In addition,a case of Tawarayama tunnel subjected to the 2016 Kumamoto earthquake is studied.Discussion on the possible influence factors aims at improving the performancebased aseismic design of tunnels.Finally,restoration design criterion and methods are presented taking Tawarayama tunnel as an example. 展开更多
关键词 MOUNTAIN TUNNEL Seismic damage Influence factor RESTORATION method
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传统绿肥贵州山地景观化利用潜力评价 认领
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作者 张钦 姚单君 +6 位作者 吴兴洪 冉斌 张爱华 王文华 况胜剑 朱青 曹卫东 《热带作物学报》 CSCD 北大核心 2020年第7期1477-1483,共7页
为了促进贵州观光农业与生态环境的协调发展,本研究对传统绿肥贵州山地景观化利用潜力进行评价。以贵州主要种植的传统绿肥光叶苕子(Vicia villosa var.)、紫云英(Astragalus sinicus L.)、箭筈豌豆(Vicia sativa L.)、肥田萝卜(Raphanu... 为了促进贵州观光农业与生态环境的协调发展,本研究对传统绿肥贵州山地景观化利用潜力进行评价。以贵州主要种植的传统绿肥光叶苕子(Vicia villosa var.)、紫云英(Astragalus sinicus L.)、箭筈豌豆(Vicia sativa L.)、肥田萝卜(Raphanus sativus L.)、山黧豆(Lathyrus cicera L.)、油葵(Oil-sunflower)、二月兰[Orychophragmus violaceus(L.)O.E.Schulz]为研究对象,分析其花朵时空分布特征、花朵视觉特性等景观效益,以及各绿肥作物的生长特性及养分效益。二月兰的开花时间最早,随后是肥田萝卜、山黧豆、紫云英,接着是光叶苕子、箭筈豌豆,而油葵是夏季绿肥,初花期为6月中旬,花穗期17~43 d,花期长短表现依次为二月兰>肥田萝卜>油葵>光叶苕子>紫云英>山黧豆>箭筈豌豆。花朵分布高度为油葵150~200 cm、肥田萝卜75~95 cm、二月兰与光叶苕子及箭筈豌豆25~50 cm、紫云英和山黧豆15~25 cm。单株花朵数光叶苕子最多。单朵花面积油葵最大。单株花面积光叶苕子最大。结合观光与保育目标,可利用绿肥作物打造2—3月间的二月兰蓝紫色花海,3—4月间的紫云英紫红色花海、肥田萝卜白色花海,4月间的光叶苕子紫色花海,6—7月间的油葵黄色花海,以丰富贵州观光休闲农业的观光色调,延长观光时间,实现观光品牌的多样化。 展开更多
关键词 绿肥 景观 山地 农业 效益
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Unit 7 What’s the highest mountain in the world? 认领
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《时代英语:初中》 2020年第2期51-56,79,共7页
重点知识园地重点单词1.tour n.&v.旅行;旅游My brother has just left Sydney for a tour of the world.我哥哥刚离开悉尼去周游世界。We tour by car every summer.每年夏天我们都驾车旅行。拓展touristn.旅行者;观光者,2.protect... 重点知识园地重点单词1.tour n.&v.旅行;旅游My brother has just left Sydney for a tour of the world.我哥哥刚离开悉尼去周游世界。We tour by car every summer.每年夏天我们都驾车旅行。拓展touristn.旅行者;观光者,2.protect v.保护;防护protect...from/against...保护……免遭……A purple headscarf protected her from/against the wind.一条紫色头巾为她挡风。 展开更多
关键词 最高级 完成句子 Unit 7 What’s the highest mountain in the world 比较级
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