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Geochemical Characteristics and Sources of Ore-forming Fluids of the Mayuan Pb-Zn Deposit,Nanzheng,Shaanxi,China 被引量:5
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作者 LIU Shuwen LI Ronxi +3 位作者 CHI Guoxiang ZENG Rong LIU Lingfang SHI Shun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第3期783-793,共11页
The Mayuan stratabound Pb-Zn deposit in Nanzheng,Shaanxi Province,is located in the northern margin of the Yangtze Plate,in the southern margin of the Beiba Arch.The orebodies are stratiform and hosted in breciated do... The Mayuan stratabound Pb-Zn deposit in Nanzheng,Shaanxi Province,is located in the northern margin of the Yangtze Plate,in the southern margin of the Beiba Arch.The orebodies are stratiform and hosted in breciated dolostone of the Sinian Dengying Formation.The ore minerals are primarily sphalerite and galena,and the gangue minerals comprise of dolomite,quartz,barite,calcite and solid bitumen.Fluid inclusions from ore-stage quartz and calcite have homogenization tempreatures from 98 to 337℃ and salinities from 7.7 wt%to 22.2 wt%(NaCl equiv.).The vapor phase of the inclusions is mainly composed of CH_4 with minor CO_2 and H_2S.The δD_(fluid) values of fluid inclusions in quartz and calcite display a range from-68‰ to-113‰(SMOW),and the δ^(18)O_(fluid)values calculated from δ^(18)O_(quartz) and δ^(18)O_(calcite) values range from 4.5‰ to 16.7‰(SMOW).These data suggest that the ore-forming fluids may have been derived from evaporitic sea water that had reacted with organic matter.The δ^(13)C_(CH4) values of CH_4 in fluid inclusions range from-37.2‰ to-21.0‰(PDB),suggesting that the CH_4 in the ore-forming fluids was mainly derived from organic matter.This,together with the abundance of solid bitumen in the ores,suggest that organic matter played an important role in mineralization,and that the thermochemical sulfate reduction(TSR) was the main mechanism of sulfide precipitation.The Mayuan Pb-Zn deposit is a carbonate-hosted epigenetic deposit that may be classified as a Mississippi Valley type(MVT) deposit. 展开更多
关键词 fluid inclusion ore-forming fluids organic matter mayuan Pb-Zn deposit shaanxi
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Urban Spatial Form Optimization Strategies Based on the Principle of Climate Adaptability of Regional Architecture: A Case Study of Traditional Cave Dwelling Villages in Northern Shaanxi Province
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作者 QI Zizhuo YANG Xin 《Journal of Landscape Research》 2024年第3期1-7,共7页
A multitude of climate-adaptive design approaches are embedded in regional architecture,which have a positive impact on addressing the deformed development of urban spatial patterns and the dual challenges of climate ... A multitude of climate-adaptive design approaches are embedded in regional architecture,which have a positive impact on addressing the deformed development of urban spatial patterns and the dual challenges of climate and resources.This paper examines the principles of climate adaptability embedded in the site layout and spatial organization characteristics of traditional cave dwelling villages in northern Shaanxi Province.The extracted climate adaptability principles are summarized,and the resulting design strategies that are well-suited to the contemporary urban space form are presented.Through analysis,it can be observed that traditional cave dwelling villages in northern Shaanxi are predominantly situated on south-facing slopes in proximity to water at low altitudes.These villages are characterized by compact building groups and east-west development,which is constrained by the elements of mountains and rivers.A two-level street system is generated,comprising streets parallel to the contour line and roadways perpendicular to the contour line.This results in the formation of a courtyard form enclosed by mountains.Such site layout and spatial organization exhibit excellent climate adaptability with regard to heat,ventilation,and wind storage.In light of the aforementioned considerations,the following urban spatial form design strategies are put forth:①the topographic height difference can be exploited to obtain sufficient sunshine;②the group shape can be optimized in order to reduce building energy consumption;③the best orientation of the building can be chosen to take account of both winter and summer conditions;④the height and length can be combined in order to form natural masking;⑤the D/H ratio of streets and roadways should be controlled to achieve a balance between heat gain and cooling of groups;⑥vents should be set appropriately to optimize group ventilation;⑦climate buffers should be established to increase the level of climate response. 展开更多
关键词 Traditional cave dwellings in northern shaanxi Urban spatial form Outdoor thermal environment
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Analysis of the Current Situation of Drug Clinical Trial Institutions in Shaanxi Province
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作者 Yurong Zhang Qi Zhang +4 位作者 Li Wang Rui Xu Lili Zhao Enze Li Xin Wang 《Journal of Clinical and Nursing Research》 2024年第1期78-87,共10页
To understand the current situation of institutional registration in Shaanxi Province after the implementation ofregistration system management in drug clinical trial institutions.Relevant information was collected on... To understand the current situation of institutional registration in Shaanxi Province after the implementation ofregistration system management in drug clinical trial institutions.Relevant information was collected on the“Announcement on the Accreditation of Drug Clinical Trial Institutions”issued by the National Medical Products Administration from 2005 to August 2022,the record management information system of drug and medical device clinical trial institutions,and the drug clinical trial registration and information publicity platform.A retrospective analysis was carried out in terms of institutional development,regional distribution,registered majors,principal investigators,and the number of drug clinical trials.After the implementation of institution registration,the number of drug clinical trial institutions in Shaanxi Province increased by 47.4%,884 principal investigators were registered,the number of registered majors expanded from 58 qualified to 117,and the professional scope increased by 50.4%.The policy of institution registration is conducive to promoting the rational use of medical resources and the development of drug clinical trial institutions and improving the healthy development of the pharmaceutical industry in Shaanxi Province. 展开更多
关键词 Drug clinical trial Institution registration Registered majors Current situation analysis Professional group shaanxi Province
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Thinking on Effective Methods of Successful Prediction of Geological Hazards in Shaanxi, China
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作者 Chaowei Yao Yonghong Li +3 位作者 Yiping He Hui Li Chaomei Xu Ping Fang 《International Journal of Geosciences》 CAS 2023年第3期271-289,共19页
In the process of human survival and development, it is inevitable to transform the original state of the world, thus forming a contradiction between the earth and the earth. The violent form of this contradiction is ... In the process of human survival and development, it is inevitable to transform the original state of the world, thus forming a contradiction between the earth and the earth. The violent form of this contradiction is geological disasters. Geological disasters pose a threat to human life and property, and cause damage caused by natural or human factors, often causing casualties. The destruction process of geological disasters is usually a gradual process, showing many pre-disaster symptoms, such as local landslides, surface cracks, building deformation, tree skew, and ground sound. Evacuation can be avoided in advance according to the disaster precursors, so as to avoid casualties and achieve successful prediction. By reviewing the general situation of geological disasters in Shaanxi Province and the casualties in 2020, the difficulties in the prevention and control of geological disasters are summarized. In view of these difficulties, an on-site investigation, visit and analysis of geological disaster points and successful forecast points in Shaanxi Province in 2020 were conducted. In addition, combined with actual cases and years of work experience, the successful prediction experience of geological disasters was discussed from 8 aspects. Finally, the “Regulations on the Reward for Successful Geological Disaster Forecasting in Shaanxi Province” was revised in order to improve the successful prediction ability of geological disasters in Shaanxi Province and even the whole country, provide reference for future prevention and control of geological disasters, and effectively protect the safety of people’s lives and property. 展开更多
关键词 Geological Hazards Successful Forecast shaanxi Province China
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Dry Intrusion Analysis of A Heavy Rainstorm in Southern Shaanxi 被引量:2
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作者 刘瑞芳 郭大梅 +1 位作者 李萍云 侯建忠 《Meteorological and Environmental Research》 CAS 2010年第12期25-29,共5页
[Objective] One regional rainstorm weather in the south area of Shaanxi was expounded.[Method] By employing the NCEP/NCAR 1°×1°reanalysis data,routine observation and automatic precipitation station dat... [Objective] One regional rainstorm weather in the south area of Shaanxi was expounded.[Method] By employing the NCEP/NCAR 1°×1°reanalysis data,routine observation and automatic precipitation station data,the large scale circulation background field of regional precipitation in the south area of Shaanxi province from July 16-18 in 2010 was expounded.By dint of physical quantity such as the meridional wind,relative humidity and false relative temperature,the characteristics of dry intrusion and its role in rainstorm were expounded.[Result] The mild and high latitude at 500 hPa was stable.The continental high pressure and subtropical high pressure were stable.The 700 and 850 hPa shear lines or low vortexes were the main influence system that resulted into large scale of rainstorm in south Shaanxi.The landing typhoon had distinct influences on the importance of storm.The influence of typhoon and subtropical high was mutual.It not only formed and strengthened the torrent in the low air,also transmitted water vapor and energy incessantly to the south area of Shaanxi,playing an important role in augment of rainstorm.There were two distinct dry intrusions in the rainstorm process,showing a dense dry layer in the high layer of convective layer.The existence of dry layer was conductive to the accumulation of convective unstable energy in the low layer.The release of convective unstable energy could transmit warm and wet airstream in the low level to the higher level,being conductive to the occurrence of precipitation.The analysis of θse in the warp direction vertical profile suggested that there was frontal zone in this rainstorm process and the dry air activity in this rainstorm process was very strong.[Conclusion] The study provided theoretical reference to the forecast in future. 展开更多
关键词 RAINSTORM Dry air intrusion South area of shaanxi China
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Analysis of Meteorological Conditions of Freeze Damage to Citrus in Southern Shaanxi in the Winter of 2010 and Defensive Countermeasures 被引量:4
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作者 柏秦凤 王景红 +3 位作者 霍治国 梁轶 张维敏 郭民主 《Agricultural Science & Technology》 CAS 2013年第3期444-449,共6页
In order to take advantage of the climate resources more effectively ac- cording to the local circumstances and to plan and develop the citrus industry in Southern Shaanxi more reasonably. On the basis of the investig... In order to take advantage of the climate resources more effectively ac- cording to the local circumstances and to plan and develop the citrus industry in Southern Shaanxi more reasonably. On the basis of the investigation of freeze dam- age to citrus occurring in Southern Shaanxi in the winter of 2010, the climatic back- ground for the formation of this freeze damage was analyzed. In combination with the freeze damage indicators during the overwintering period and the harmful accu- mulated cold during the cold wave, indexes for grading the freeze damage in southern Shaanxi were analyzed and verified, and the perspective of grading the freeze damage using the harmful accumulated cold during the cold wave was also presented. Through analyzing the extremely lowest temperature and the harmful ac- cumulated cold in the winter of 2010 and in history at 12 citrus growing counties (districts) in Ankang area and Hanzhong area, the reasons why the freeze damage to citrus during the overwintering period was severer in the west than in the east of Southern Shaanxi were discussed, and the results obtained were basically consistent with the actual situation observed from investigation. Finally, defensive countermea- sures against the freeze damage to citrus during the overwintering period were put forward from several aspects. 展开更多
关键词 CITRUS Southern shaanxi Freeze damage during the overwintering peri- od Meteorological conditions Defensive countermeasures
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Rural Tourism Development Strategies of Shaanxi Province in North China 被引量:1
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作者 丁华 岳丹 董风 《Journal of Landscape Research》 2011年第8期70-73,81,共5页
Rural tourism development in Shaanxi Province is introduced:largely improved with a fast speed; large quantity of rural tourist sites covering a great range, a complete product system; more and more investment; new pr... Rural tourism development in Shaanxi Province is introduced:largely improved with a fast speed; large quantity of rural tourist sites covering a great range, a complete product system; more and more investment; new progress in the construction of management system and guarantee system; progress in the construction of new countryside. Development advantages and opportunities of rural tourism industry in Shaanxi Province are analyzed: rich humanistic, natural and agricultural resources are inborn advantages of its rural tourism development; excellent location and increasing GDP per capita provides more market opportunities for rural tourism development; prospering tourism industry provides an excellent exterior environment for rural tourism development; a complete traffic network facilitates rural tourism development. Then development strategies for the rural tourism industry of Shaanxi Province are given:government should be a guider, planning should be accelerated, layouts reasonably designed, rural tourism development concepts clarified; brands should be created to drive the overall development by using several prominent scenic spots and promote the scale-development of rural tourism industry; the core strategy is to launch concrete programs and promote rural tourism development; publicity should be enhanced to make the good reputation of rural tourism more popular; standard regulations should be made, special staff trained for rural tourism services and the system of "farm-stay" association improved. 展开更多
关键词 shaanxi PROVINCE RURAL TOURISM Development STRATEGIES
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Analysis of Heavy Metal Content in Food Crops Planted Along the Shaanxi Inner Mongolia Expressway 被引量:2
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作者 艾海舰 张雄 +2 位作者 刘翠英 纪晓玲 卜耀军 《Agricultural Science & Technology》 CAS 2009年第3期108-111,119,共5页
To understand the effect of the running of Shaanxi Inner Mongolia Expressway on food crops planted along the sides, we determined the heavy metal contents(Zn, Pb, Cu and Cb) in the digestion solutions of the root, ste... To understand the effect of the running of Shaanxi Inner Mongolia Expressway on food crops planted along the sides, we determined the heavy metal contents(Zn, Pb, Cu and Cb) in the digestion solutions of the root, stem and leaf from rice and corn. The results showed that highway promoted the accumulation of heavy metal elements in corn and rice. Compared with the CKs(crops produced where no highway extend), contents of heavy metal elements in two crops tested from two sampling sites were both over standard. This indicates that food crops planted within 100 m away from the highway are been polluted by heavy metals, which is directly related with the running of Shaanxi Inner Mongolia Expressway. Based on this, the areas within 100 m away from the highway are not suggested to cultivate food crops. 展开更多
关键词 shaanxi Inner Mongolia Expressway Food crop Heavy metal
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Construction of Monastery Garden Landscapes in Northern Shaanxi Province of China 被引量:1
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作者 张颖 商铁林 《Journal of Landscape Research》 2011年第4期13-16,21,共5页
In view of the present construction of monastery garden landscapes in northern Shaanxi,landscape features were pointed out as:harsh natural environment of monastery garden,dual functions of religion and tourism,large ... In view of the present construction of monastery garden landscapes in northern Shaanxi,landscape features were pointed out as:harsh natural environment of monastery garden,dual functions of religion and tourism,large spatial capacity of architectural complex,long history and profound cultures,and also working as botanic gardens.Problems in these monastery gardens were proposed as:poor overall landscaping design,insufficient plants of religious cultures,lacking in artistic plant furnishings showing ornamental effects and seasonal aspects of plants,plant furnishings failed to show cultural characteristics of northern Shaanxi,poor diversity and improper ratio of plant furnishings,attaching insufficient importance to vertical greening,similar plant communities.On the basis of investigating characteristics and problems of monastery garden landscapes in northern Shaanxi,layouts and plant furnishings of incense roads,religious sectors and living sectors in those gardens were analyzed,suitable plant species were given as references,so as to explore new landscape modes of "human-nature oneness" and provide useful experience for the landscape construction of monastery gardens in Shaanxi. 展开更多
关键词 NORTHERN shaanxi MONASTERY GARDEN LANDSCAPE CONSTRUCTION
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A New Species of Simulium (Diptera: Simuliidae) from Shaanxi, China 被引量:2
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作者 刘增加 安继尧 《Entomotaxonomia》 CSCD 北大核心 2009年第2期143-146,共4页
Simulium (Simulium) liubaense, sp. nov. is described based on the female specimens collected from Liuba, Shaanxi Province, China. This species is assigned to the variegotum-group of the subgenus Simulium, and is clo... Simulium (Simulium) liubaense, sp. nov. is described based on the female specimens collected from Liuba, Shaanxi Province, China. This species is assigned to the variegotum-group of the subgenus Simulium, and is closely related to S. (S.)jingfui Cai and An, 2008, S. (S.) taiwanicum Takaoka, 1979, S. (S.) hackeri Edwards 1928, S. (S.) chamlongi Takaoka and Suzuki, 1984. However it is clearly differentiated from them by the structure of cibarium, genital fork, genital plate, paraproct and cercus of the female. All the specimens are kept in the Medical Entomology Collection Gallery, Academy of Military Medical Sciences, Beijing. 展开更多
关键词 DIPTERA SIMULIIDAE SIMULIUM Simulium (Simulium) new species shaanxi Province China
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Effect of Different Land Use Patterns on Physical Properties of Soil Water in Yellow River Wetland in Shaanxi Province 被引量:2
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作者 刘云鹏 张社奇 +1 位作者 谷洁 解迎革 《Agricultural Science & Technology》 CAS 2010年第9期148-152,共5页
[Objective] This study was to reveal the effect of different land use patterns on physical characteristics of soil water in the Yellow River wetland in Shaanxi Province.[Method]Taking Yellow River wetland in Shaanxi P... [Objective] This study was to reveal the effect of different land use patterns on physical characteristics of soil water in the Yellow River wetland in Shaanxi Province.[Method]Taking Yellow River wetland in Shaanxi Province as experimental plot,we compared the physical properties of the soil water under different land use patterns and studied the physical properties and the change law of soil water during the wetland degeneration process.[Result]Under different land use patterns,soil bulk density rose with the increase of soil depth.During the degeneration process of from river wetland to reclaimed wetland(paddy field),finally to abandoned land owing to salinization,the mean soil bulk density reduced correspondingly from 1.474 to 1.522 g/cm3,finally to 1.593 g/cm3 when abandoned.Accompanying wetland degeneration,soil became compact increasingly,and the indicators of soil porosity(total porosity,capillary porosity,non-capillary porosity)were also reduced with the change of land use patterns,in which,capillary porosity and total porosity reached the extremely significant level with the change of land use patterns,and non-capillary porosity reached significant level.The changes of soil porosity condition accelerated the deterioration of wetland.Under different land use patterns,the maximum soil moisture capacity,capillary moisture capacity and minimum moisture capacity all showed a similar change law.Compared with wetland,the maximum soil moisture capacity of reclaimed land(paddy field)and salinized land respectively decreased by 5.7% and 22.3%,capillary moisture capacity by 0.2% and 19.4%,minimum moisture capacity by 2.7% and 15.9%.Of the three land use patterns,wetland displayed both higher water holding capacity and water drainage capacity over reclaimed land(paddy field)and salinized land.By comparison with wetland,the reclaimed land(paddy field)and salinized land respectively decreased by 12.4% and 15.2% in total water holding capacity,and by 2.7% and 15.9% in total water drainage capacity.[Conclusion]To conserve the water resource in Yellow River wetland,regulate the hydrological cycle and enhance drought and water logging resistances,it should be noted that reasonable countermeasures be taken to exploit the state-owned forest land and paddy field around the wetland and the related resources. 展开更多
关键词 Yellow River wetland in shaanxi Land use pattern Soil bulk density Water holding capacity Water drainage capacity
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A New Species of the Genus Chorthippus (Orthoptera: Arcypteridae) from North of Shaanxi, China 被引量:1
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作者 王延峰 郑哲民 《Entomotaxonomia》 CSCD 北大核心 2006年第1期17-20,共4页
In this paper, a new species of the genus Chorthippus is described from North of Shaanxi Province, China, namely: Chorthippus wuqiensis sp. nov. The type specimens are deposited in the Institute of Zoology, Shaanxi N... In this paper, a new species of the genus Chorthippus is described from North of Shaanxi Province, China, namely: Chorthippus wuqiensis sp. nov. The type specimens are deposited in the Institute of Zoology, Shaanxi Normal University. 展开更多
关键词 Onhoptera ACRIDOIDEA ARCYPTERIDAE CHORTHIPPUS new species North of shaanxi Province China
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Study on Development Countermeasures of Cave Dwellings in Northern Area of Shaanxi Province in China
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作者 程军 《Journal of Landscape Research》 2011年第6期90-93,共4页
In view of traditional house in northern area of Shaanxi Province which was cave dwelling,based on cave dwelling and its development environment,the paper had analyzed architectural characteristics and use value of ca... In view of traditional house in northern area of Shaanxi Province which was cave dwelling,based on cave dwelling and its development environment,the paper had analyzed architectural characteristics and use value of cave dwelling and its development in northern Shaanxi,and then pointed out that cave dwelling development had been reduced into an awkward situation.By using SWOT analysis method,the strengths,weaknesses,opportunities and threats of cave dwellings had been summarized.In terms of strengths,cave dwelling had ecological advantage as native architecture,was constructed based on local conditions,could solve land,energy and environment problems on Loess Plateau,and abounded in aesthetic value of native feature.In terms of weaknesses,village layout lacked of integrity,transportation was not convenient,indoor ventilation and lighting were insufficient,and pattern and space were simplified and stereotyped.In terms of opportunities,it stressed architectural ecology having received more and more attention in the world,and exploration and application of underground civil architecture.In terms of threats,it lied in construction technology of cave dwelling,contradiction between cave dwelling and urbanization and between cave dwelling and modern life,and management mode of restricted type.On this basis,it suggested that cave dwelling development in northern Shaanxi should transform people's traditio-nal concept through correct guidance of public voice;strive to eliminate weakness of cave dwelling;improve cave environment by enhancing infrastructure construction;develop characteristic cave dwelling cultural tourism in northern Shaanxi,and construct new socialist countryside of northern Shaanxi character. 展开更多
关键词 CAVE DWELLING in NORTHERN area of shaanxi SWOT analysis Development
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Comprehensive Effects of Eco-tourism Development on Tourism Destinations in South Shaanxi Province
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作者 李文正 《Journal of Landscape Research》 2009年第8期75-79,84,共6页
Eco-tourism theories were taken as the instruction in this study,qualitative and quantitative research methods were also combined to investigate and conduct questionnaire processing to nearby residents of 10 eco-touri... Eco-tourism theories were taken as the instruction in this study,qualitative and quantitative research methods were also combined to investigate and conduct questionnaire processing to nearby residents of 10 eco-tourism scenic areas in south Shaanxi Province,so as to quantify and evaluate the various effects at different levels of eco-tourism development on tourism destinations in this region.Particularly,the quantitative value and weight value of economic,social and environmental effects were utilized to quantify,analyze and evaluate the comprehensive effects generated by eco-tourism development in south Shaanxi Province.It was found that the comprehensive effects were 'good',however,these 3 kinds of effects have not been coordinated well,thus the characteristics and requirements of eco-tourism have not been well demonstrated. 展开更多
关键词 SOUTH shaanxi PROVINCE ECO-TOURISM TOURISM DESTINATION Comprehensive effects
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Shaanxi News标题语言的意识形态分析
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作者 付丹亚 彭治民 《商洛学院学报》 2016年第2期79-85,共7页
从主题、词汇选择、时态及主位化等角度分析发现,Shaanxi News新闻标题不存在为了生成主观话语对时态的扩展性使用,标题的主位结构没有为了达到一定的主观意愿刻意违背语篇发展的规律,从而客观报道了陕西各个方面的发展动态,以及与陕西... 从主题、词汇选择、时态及主位化等角度分析发现,Shaanxi News新闻标题不存在为了生成主观话语对时态的扩展性使用,标题的主位结构没有为了达到一定的主观意愿刻意违背语篇发展的规律,从而客观报道了陕西各个方面的发展动态,以及与陕西人生活息息相关的节日、风俗、特色饮食以及艺术形式,塑造了积极、乐观、向上的陕西人以及发展中的美丽新陕西形象。 展开更多
关键词 shaanxi NEWS 新闻标题 意识形态 主题 词汇选择 主位化 时态
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Exploration of Eco-economic Development in Ecological Fragile Region——A Case Study on Wuqi County in Shaanxi Province 被引量:1
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作者 张冰 王冬 《Agricultural Science & Technology》 CAS 2012年第7期1524-1531,共8页
[Objective] The aim was to explore eco-economy in ecological fragile region with Wuqi County in Shaanxi Province as an example. [Method] Eco-economy development and major environmental problems in Wuqi County in Shaan... [Objective] The aim was to explore eco-economy in ecological fragile region with Wuqi County in Shaanxi Province as an example. [Method] Eco-economy development and major environmental problems in Wuqi County in Shaanxi Province were researched based on local social and economic conditions, population of impoverished people and environment vulnerability. [Result] The areas with vulnerable environment and backward economy should establish a virtuous circle between economy and environment and a sustainable model of economic development. [Conclusion] It is significant to change the severe situation of environment deterioration and to promote ecological civilization. 展开更多
关键词 Ecological fragile region Ecological economy Environment protection Virtuous circle Wuqi County in shaanxi Province
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An Important Ornithischian Tracksite in the Early Jurassic of the Shenmu Region,Shaanxi,China 被引量:11
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作者 LI Jianjun Martin G.LOCKLEY +3 位作者 ZHANG Yuguang HU Songmei MATSUKAWA Masaki BAI Zhiqiang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第1期1-10,共10页
A large track site with multiple, well-preserved trackways of an Early Jurassic quadrupedal ornithischian dinosaur is the first report of Moyenisauripus-like trackways from Asia, herein named Shenmuichnus youngteilhar... A large track site with multiple, well-preserved trackways of an Early Jurassic quadrupedal ornithischian dinosaur is the first report of Moyenisauripus-like trackways from Asia, herein named Shenmuichnus youngteilhardorum. The tracks occur in a clastic fluvial sequence in the Fuxian Formation in Shenmu County, Shaanxi Province, which is in the same general region as the discovery site of Sinoichnites, the first dinosaur track reported from China. Based on size and morphology, it is likely that Sinoichnites, which is now lost, also represents an ornithischian. The Shenmuichnus youngteilhardorum trackways show two modes of preservation: the first representing deeper tracks, with sediment rims, results in Deltapodus-like tracks, with indistinct pes digit traces and sub-circular manus traces, the second produces Moyenosauripus-like tracks, with clear tridactyl and pentadactyl digit traces in the pes and manus respectively. Thus the Shenmu trackways play a key role in resolving globally significant ichnotaxonomic problems surrounding the nomenclature of Sinoichnites, Moyenosauripus, Deltapodus and other named (Ravatichnus) and unnamed trackways from Asia, Africa and Europe. In addition they shed important light on the paleogeographical and paleoecological distribution of quadrupedal ornithischians in the Early Mesozoic. The track site has been the focus of a major excavation to transfer the trackways from their original remote location to the new Shenmu Museum, in Shenmu City. Other tracksites in the area which reveal Anomoepus, Grallator and the Deltapodus morphotype, together with Shenmuichnus and plant fossil evidence, suggest an Early Jurassic age for the tracksite. 展开更多
关键词 dinosaur tracks Early Jurasic Shenmu shaanxi
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Changes in Ecosystem Service Values on the Loess Plateau in Northern Shaanxi Province,China 被引量:9
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作者 LI Jing REN Zhi-yuan 《Agricultural Sciences in China》 CAS CSCD 2008年第5期606-614,共9页
The Loess Plateau in northern Shaanxi Province of China covers Yulin, Yan'an, and Tongchuan cities mainly. The kind of physiognomy is complicated and various, including the transitional region of the sand and wind, t... The Loess Plateau in northern Shaanxi Province of China covers Yulin, Yan'an, and Tongchuan cities mainly. The kind of physiognomy is complicated and various, including the transitional region of the sand and wind, the hilly-gully fragile region, the pimple mound region from North to South. Large-scale land reclamation projects that are severely affecting these ecosystems have been implemented. In this paper, we reported an investigation to the changes in land use and ecosystem services on the Loess Plateau in northern Shaanxi Province from 1978 to 2000. We used three LANDSAT TM and/or ETM data sets to estimate the changes in the size of five land-cover/land-use categories, and we also used previously published value coefficients to estimate the changes in the value of ecosystem services delivered by each land category. Finally, we ranked the contribution of various ecosystem functions to the overall value of the ecosystem services, we have estimated that the annual value of the ecosystem services is 56.95 billon RMB yuan in the Loess Plateau in northern Shaanxi Province in 2000. In the region, from 1978 to 2000, the economic value of the fixing carbon was higher, the economic value of water conservation was the lowest, but the economic value of the NPP, fixing carbon, and supplying oxygen accounted for above ninety percent of the total value, obviously the vegetation created the biggest ecosystem service value. We can conclude that future land-use policy formulation should give precedence to the conservation of these ecosystems over uncontrolled reclamation, and that further land reclamation should be based on rigorous environmental impact analyses. 展开更多
关键词 LANDUSE ecosystem services the value ecosystem functions the Loess Plateau northern shaanxi Province
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Quantitative analysis of the dynamic change and spatial differences of the ecological security: a case study of Loess Plateau in northern Shaanxi Province 被引量:5
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作者 LI Jing REN Zhiyuan ZHOU Zixiang 《Journal of Geographical Sciences》 SCIE CSCD 2006年第2期251-256,共6页
Using the theory and method of the ecological footprint, and combining the changes of regional land use, resource environment, population, society and economy, this paper calculated the ecological footprint, ecologica... Using the theory and method of the ecological footprint, and combining the changes of regional land use, resource environment, population, society and economy, this paper calculated the ecological footprint, ecological carrying capacity and ecological surplus/loss in 1986-2002 on the Loess Plateau in northern Shaanxi Province. What is more, this paper has put forward the concept of ecological pressure index, set up ecological pressure index models, and ecological security grading systems, and the prediction models of different ecological footprints, ecological carrying capacity, ecological surplus and ecological safety change, and also has assessed the ecological footprint demands of 10,000 yuan GDE The results of this study are as follows: (1) the ecological carrying capacity in northern Shaanxi shows a decreasing trend, the difference of reducing range is the fastest; (2) the ecological footprint appears an increasing trend; (3) ecological pressure index rose to 0.91 from 0.44 during 1986-2002 on the Loess Plateau of northern Shaanxi with an increase of 47%; and (4) the ecological security in the study area is in a critical state, and the ecological oressure index has been increasing rapidlv. 展开更多
关键词 regional ecological security dynamic change spatial difference quantitative analysis the Loess Plateau in northern shaanxi Province
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New Thought of Meteorological Forecasting and Warning Models of Geological Disasters in Loess Plateau of North Shaanxi
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作者 高维英 李明 +1 位作者 杜继稳 王雁林 《Meteorological and Environmental Research》 CAS 2010年第8期12-16,共5页
The study established daily comprehensive precipitation equations and calculated respective critical daily comprehensive precipitation value of loess-collapse disasters and landslide disasters by dint of the geologica... The study established daily comprehensive precipitation equations and calculated respective critical daily comprehensive precipitation value of loess-collapse disasters and landslide disasters by dint of the geological disasters and corresponding precipitation data in 47 years.Considering geological disaster risk divisions,precipitation influence coefficient and daily comprehensive precipitation,hourly rolling daily-forecasting and hourly warning fine and no-gap models on the base of high temporal and spatial resolution rainfall data of automatic meteorological station were developed.Through the verifying of combination of dynamical forecasting model and warning model,the results showed that it can improve efficiency of forecast and have good response at the same time. 展开更多
关键词 Loess Plateau of North shaanxi Geological disasters Daily comprehensive precipitation Forecasting and warning models China
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