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Remote Sensing Monitoring of the Subalpine Coniferous Forests and Quantitative Analysis of the Characteristics of Succession in East Mountain Area of Tibetan Plateau——A Case Study With Zamtang County 被引量:5
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作者 张学儒 张镱锂 +2 位作者 刘林山 张继平 高俊刚 《Agricultural Science & Technology》 CAS 2011年第6期926-930,共5页
The study area lies in the Dadu River drainage area in upstream Yangtze River.The spatial distribution of subalpine coniferous forests in 1989 and 2009 was extracted by means of a combined method of object orientation... The study area lies in the Dadu River drainage area in upstream Yangtze River.The spatial distribution of subalpine coniferous forests in 1989 and 2009 was extracted by means of a combined method of object orientation and visual interpretation,and then the overlaying analysis of these data was conducted.The type and spatial location of succession were discovered and served as the sample of dependant variable.Meanwhile,supported by GIS technology and based on DEM and thematic data,the eight variables including altitude,slope,sin and cosin of aspect,curvity of land surface,and distance to residential area,cultivated land and road were extracted served as the sample of spatial succession of subalpine coniferous forests to fit Logistic Regression,and then the contribution of each independent variable as well as the spatial property of the occurrence probability of succession was calculated.The results suggested that,during the succession of subalpine coniferous forests to meadow,the closer to the residential area and cultivated land,the greater the contribution to succession is.In particular,when the distance to the residential area decreases by one unit,the probability for its conversion to meadow will be increased by 1.15 times.During the succession of subalpine coniferous forests to deciduous-broadleaved shrubs,the sin of aspect and distance to residential area contribute more,and the probability of succession increases with increasing degree of northwardness,i.e.when the degree of northwardness increases by one unit,the probability will be increased by 1.2 times.The quantitative analysis of spatial succession property of subalpine coniferous forests will supply scientific basis to the protection and restoration of subalpine coniferous forests. 展开更多
关键词 Subalpine Coniferous Forests Logistic Regression GIS East mountain Area of Tibetan plateau
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Glacier change in the Tanggula Mountains, Tibetan Plateau,in 1969-2015 被引量:10
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作者 DUAN Hong-yu YAO Xiao-jun +5 位作者 LIU Shi-yin GAO Yong-peng QI Miao-miao LIU Juan ZHANG Da-hong LI Xiao-feng 《Journal of Mountain Science》 SCIE CSCD 2019年第11期2663-2678,共16页
To improve our knowledge of glacier change in the Tanggula Mountains located in the northeast of the Tibetan Plateau,we delineated outlines of the glaciers in 1991 and 2015 using Landsat TM/OLI images and compared the... To improve our knowledge of glacier change in the Tanggula Mountains located in the northeast of the Tibetan Plateau,we delineated outlines of the glaciers in 1991 and 2015 using Landsat TM/OLI images and compared them with the reported glacier data in the First Chinese Glacier Inventory in 1969 and the Second Chinese Glacier Inventory in 2007.These comparisons showed that the glacier area and ice volume decreased by 524.8 km2 and 37 km3,respectively.The majority of the glacier area loss was concentrated in the area class of 1-5 km2,between 5300 m and 5500 m in elevation,on north and east facing slopes and in the Dam Qu River basin.These glacier changes exhibited spatial and temporal differences.The glacier retreat rate gradually increased from 1969 to 2015,and the rate in the east was higher than that in the west.From 1969 to 2015,the warming rate in the Tanggula Mountains was 0.38°C/10a,while the annual precipitation only increased by 0.4%.The slight increase in the amount of precipitation made a limited contribution to glacier change,while the change in temperature led to noticeable shrinkage of the glaciers.Contrary to the retreat or stagnation of most glaciers in the study area,there were 10 glaciers that experienced clear advance in 1986-2015 with noticeable increases in both area and length.Whether or not these 10 glaciers are surge glaciers requires further study. 展开更多
关键词 GLACIER CHANGE GLACIER INVENTORY Advancing glaciers Climate CHANGE Tanggula mountainS TIBETAN plateau
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Design of Plateau and Mountain Ethnic Settlements with Adaptive Spatial Features:A Case Study of Jiayin Town 被引量:1
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作者 XU Jian WANG Ruli SHAN Xin 《Journal of Landscape Research》 2020年第5期65-70,共6页
Jiayin Town,Honghe Prefecture,Yunnan Province is composed of four elements,forest,water,farmland and village.The highly adaptive human settlement environmental features of ecologyproduction-living space reflect the ad... Jiayin Town,Honghe Prefecture,Yunnan Province is composed of four elements,forest,water,farmland and village.The highly adaptive human settlement environmental features of ecologyproduction-living space reflect the adaptability of ethnic settlements on plateaus and mountains to the natural environment and geographical conditions.In this article,based on the unique natural environment and regional characteristics of Jiayin Town,the background features of the human settlement environment,the features of altitude,slope and aspect,the spatial features of forests and grasslands and the features of farmland and villages were analyzed,and design concepts of coordinating and integrating the development of ecology-production-living space,integrating and transforming natural resources into human settlement environmental resources and establishing village public awareness and the design strategies of cultivating culture with life and adopting things with rural quality were proposed,in order to provide scientifi c basis for the protection and development of the plateau and mountain ethnic villages and ensure their harmonious and orderly development. 展开更多
关键词 plateau and mountain ADAPTABILITY Rural design Ecology-production-living space
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Geomorphic features of Quaternary glaciation in the Taniantaweng Mountain, on the southeastern Qinghai-Tibet Plateau 被引量:5
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作者 ZHANG Wei CHAI Le +5 位作者 IAN S.Evans LIU Liang LI Ya-peng QIAO Jing-ru TANG Qian-yu SUN Bo 《Journal of Mountain Science》 SCIE CSCD 2019年第2期256-274,共19页
We present geomorphological evidence for multiple glacial fluctuations during the Quaternary in the Taniantaweng Mountain, which is situated at the transition zone of the southeastern Qinghai-Tibet Plateau and the Yun... We present geomorphological evidence for multiple glacial fluctuations during the Quaternary in the Taniantaweng Mountain, which is situated at the transition zone of the southeastern Qinghai-Tibet Plateau and the Yunnan-Guizhou Plateau. To reconstruct the history of glacial evolution during the Quaternary Glaciation, we present a ~13000 km^2 geomorphologic map(1:440,000) for the Quaternary glaciations, as well as three electron spin resonance(ESR) ages and three optically stimulated luminescence(OSL) ages from the landforms. By integrating these with ages from previous studies, four major glacial advances are identified during marine oxygen isotope stages(MIS) 6, 3, 2 and 1. This glacial chronology is in reasonable agreement with existing glacial chronologies from other parts of the Hengduan Mountains and surrounding mountains. Glaciers had extended to the Yuqu River during the glacial maximum advance(MIS 6), but became successively more restricted from MIS 3 to MIS 1. The glacial distribution show that precipitation brought by the south Asian monsoon might play a primary role in driving glacial advances during the last glacial period in the southeastern Qinghai-Tibet Plateau. 展开更多
关键词 Qinghai-Tibet plateau Taniantaweng mountain GLACIAL LANDFORM ESR DATING OSL DATING South Asian monsoon
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THE GLOBAL TECTONIC SYSTEMS AND A LATITUDINAL MOUNTAIN-PLATEAU CHAIN ON THE NORTH HEMISPHERE
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作者 Ma Zongjin(Institute of Geology,China Seismological Bureau,Beijing 100029,China) 《地学前缘》 EI CAS CSCD 2000年第S1期344-345,共2页
Three global tectonic systems that formed since the middle Jurassic (160Ma ago)are outlined based on the global map of the Cenozoic and Mesozoic tectonics edited by Ma Zongjin et al.(1996).They are the circum\|Pacific... Three global tectonic systems that formed since the middle Jurassic (160Ma ago)are outlined based on the global map of the Cenozoic and Mesozoic tectonics edited by Ma Zongjin et al.(1996).They are the circum\|Pacific tectonic system,the mid\|ocean ridge tectonic system and the intra\|continental tectonic system of the north hemisphere.The map shows that about 80% of the total length of the continental orogens are concentrate on the north hemisphere of the earth,of which a latitudinal mountain\|plateau chain occur within a zone between north latitude 20°and 50°.Seismic and volcanic activities demonstrate that the intracontinental tectonic system on the north hemisphere is still active.Whilst distribution of the continental deep\|focus earthquakes and almost ultra high\|pressure rock found so far over the World,that are assumed both related to recent or previous deep subduction of continent,along with this zone.The latitudinal mountain\|plateau chain is subdivided into four active tectonic region of Qinghai—Xizang(Tibet),Iranian,eastern mediterranean and North American,both characterized by an individual similar mountain\|plateau\|basin structure with major active boundaries or controlling faults (Fig.1).These active regions are all close to primary dynamic boundaries of continent\|continent collision.Solution of source mechanisms shows that regional tectonic stress field in these regions are dominated by a nearly NS or NNE—SSW direction compression corresponding to a local plate motions and a global compressive zone.Correlation between the formation of the continental latitudinal mountain\|plateau chain on north hemisphere and the oceanic plate tectonics is discussed using the information of the “Map of Magnetic Lineations of the World’s Ocean Basins (Cande et al.,1989)”and the Cenozoic and Mesozoic tectonic evolution in the continents.Total 49 accretion units formed during 6 accretion stages of the ocean spreading in three chief oceans (the Pacific,the India and the Atlantic)si nce 160Ma ago,are subdivided.The distinguished oceanic accretion tectonics in combination with the geometrical and kinematics data of adjust continental f ragments allowed outline of the development of the continental latitudinal tecto nic zone of north hemisphere.Whilst,two global asymmetrical geodynamic systems of north\|south an east\|west direction,that may be composed of meridional conve ction,latitudinal convection and inertial flow resulting from the variation of the Earth’s rotational velocity,are used to discuss on the two global geodynamic systems in which the intracontinental latitudinal tectonic zone developed. 展开更多
关键词 GLOBAL asymmetrical SYSTEM geodynamics mountain\| plateau CHAIN SEISMOTECTONIC SYSTEM latitudinal TECTONIC zone
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THE ENVIRONMENTAL QUALITY AND RENOVATING PLAN OF THE LOESS PLATEAU AND LIUPANSHAN MOUNTAINOUS AREA IN NINGXIA
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作者 Chen Jisen Ningxia Research Institute of Environmental Protection, Yinchuan 《干旱区资源与环境》 CSCD 1993年第Z1期480-483,共4页
1. The environmental quality of the Loess Plateau and Liupanshan mountainous area in Ningxia The landuse structure in the studied region was very irrational in 1970s, the propor-tions covered by farming, forestry and ... 1. The environmental quality of the Loess Plateau and Liupanshan mountainous area in Ningxia The landuse structure in the studied region was very irrational in 1970s, the propor-tions covered by farming, forestry and animal husbandry are separately 50.91%, 6.32% and33.3%. Since 1980s, the farmland has been returned back to forestry and pasture so that 展开更多
关键词 The LOESS plateau Liupanshan mountainS Environmental Qulity
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Spatial variability and its main controlling factors of the permafrost soil-moisture on the northern-slope of Bayan Har Mountains in Qinghai-Tibet Plateau 被引量:5
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作者 cao wei sheng yu +1 位作者 wu ji-chun li jing 《Journal of Mountain Science》 SCIE CSCD 2017年第12期2406-2419,共14页
The soil moisture movement is an important carrier of material cycle and energy flow among the various geo-spheres in the cold regions.Thus, this research takes the north slope of Bayan Har Mountains in Qinghai-Tibet ... The soil moisture movement is an important carrier of material cycle and energy flow among the various geo-spheres in the cold regions.Thus, this research takes the north slope of Bayan Har Mountains in Qinghai-Tibet Plateau as a case study.The present study firstly investigates the change of permafrost moisture in different slope positions and depths. Based on this investigation, this article attempts to investigate the spatial variability of permafrost moisture and identifies the key influence factors in different terrain conditions. The method of classification and regression tree(CART) is adopted to identify the main controlling factors influencing the soil moisture movement. The relationships between soil moisture and environmental factors are revealed by the use of the method of canonical correspondence analysis(CCA). The results show that: 1) Due to the terrain slope and the freezing-thawing process, the horizontal flow weakens in the freezing period. The vertical migration of the soil moisture movement strengthens. It will lead to that the soil-moisture content in the up-slope is higher than that in the down-slope. The conclusion is contrary during the melting period. 2) Elevation, soil texture, soil temperature and vegetation coverage are the main environmental factors which affect the slopepermafrost soil-moisture. 3) Slope, elevation and vegetation coverage are the main factors that affect the slope-permafrost soil-moisture at the shallow depth of 0-20 cm. It is complex at the middle and lower depth. 展开更多
关键词 Qinghai-Tibet plateau Northern-slope of Bayan Har mountains PERMAFROST Soil moisture Spatial variability Controlling factors
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2023年12月18日甘肃积石山M_(S)6.2地震触发次生灾害快速评估 被引量:3
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作者 徐岳仁 窦爱霞 +3 位作者 李智敏 梁朋 梁泽毓 陆玲玉 《地震》 CSCD 北大核心 2024年第1期209-215,共7页
2023年12月18日甘肃积石山县发生M_(S)6.2地震,该次地震触发官亭盆地中川乡金田泥流灾害,造成严重的破坏和人员伤亡。通过震前、震后的高分辨率卫星影像对比分析,初步判断此次地震没有引发大型同震滑坡与密集砂土液化,但是震前震中区发... 2023年12月18日甘肃积石山县发生M_(S)6.2地震,该次地震触发官亭盆地中川乡金田泥流灾害,造成严重的破坏和人员伤亡。通过震前、震后的高分辨率卫星影像对比分析,初步判断此次地震没有引发大型同震滑坡与密集砂土液化,但是震前震中区发育的大量大型黄土滑坡和密集液化砂脉是由更老的地震事件触发。金田泥流灾害是物源区高含水量黏性土在强震动条件下沿沟谷发生流动所致,其发生可能与人类的耕作方式(引黄灌区震前冬季灌溉导致浅表土层含水量提高)有关。 展开更多
关键词 金田泥流 积石山 青藏高原 地震灾害链
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Simulating potential vegetation distribution in a mountainous region of the Eastern Tibetan Plateau:A case study of Barkam County
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作者 Xueru Zhang Yili Zhang +1 位作者 Linshan Liu Jiping Zhang 《Chinese Journal of Population,Resources and Environment》 2013年第2期180-186,共7页
The main objective of this study is to simulate the potential vegetation types on the basis of environmental parameters.The paper took Barkam County in a mountainous region of the Eastern Tibetan Plateau as the study ... The main objective of this study is to simulate the potential vegetation types on the basis of environmental parameters.The paper took Barkam County in a mountainous region of the Eastern Tibetan Plateau as the study area.The vegetation distribution was mapped in 1994 and 2007 based on TM remote sensing images by object-oriented interpretation method.We overlaid the two maps to find out the vegetation patches which have not changed,and took them as stable types.Fifty per cent of the stable patches were randomly sampled to operate the logistic regression with related environmental parameters;others were used as test data of simulated results.Seven environmental parameters were mapped,including elevation,slope,aspect,surface curvature,solar radiation,temperature and precipitation,based on DEM data and meteorological site data by GIS technology.The relationship between the spatial distribution of vegetation and environmental variables were quantified by logistic regression.The distribution probabilities of each vegetation type were calculated.Finally,the spatial distribution of potential vegetation was simulated.This research can provide a scientific basis for vegetation restoration and ecological construction in this area. 展开更多
关键词 potential VEGETATION simulation mountainous region of the EASTERN TIBETAN plateau LOGISTIC regression GIS
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RATIONAL UTILIZATION OF MOUNTAIN SOILS IN SOUTHEAST QINGHAI-XIZANG (TIBETAN) PLATEAU
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作者 Li Mingsen(Commission for Intngated Survey of Natural Resources, CAS, Bejing 100101 People’s Republic of China) 《Journal of Geographical Sciences》 SCIE CSCD 1996年第4期38-44,共7页
The southeast Qinghaicozang (Tibetan) Plateau is a physcal mpon ofvery complicated eco-envirorunent with optimum hydrothermal conditions. Thisregon conains not ouly vast expanse of alpine soils but also abounds in mos... The southeast Qinghaicozang (Tibetan) Plateau is a physcal mpon ofvery complicated eco-envirorunent with optimum hydrothermal conditions. Thisregon conains not ouly vast expanse of alpine soils but also abounds in mosttypes of Chinese forest soils. The distributon and tallization of soils presents avery evident horizontal-vertical zonality. At present, panial soil resources arebeing damaged and the mountain ecology also tends to be instable. So rationalcuttin and forest conservation, barren mountain afferestation, retuming thecultivated land on stop slopes to forest, controlled graking, and soil ameliorationconstitute importan means for rational use of soil resources and improvement andstabilization of mountain ecology in tyis region 展开更多
关键词 mountain ecology soil types Qinghai-Xizang (Tibetan) plateau
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高原环境山区道路农用拖拉机掺烧生物柴油污染物排放因子类型量化研究
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作者 字天曦 何超 +3 位作者 包广元 赵龙庆 李加强 刘学渊 《环境工程技术学报》 CAS CSCD 北大核心 2024年第6期1821-1828,共8页
分析农用拖拉机在高原环境山区道路下行驶时掺烧大豆油B10(10%大豆油生物柴油+90%柴油)、B30(30%大豆油生物柴油+70%柴油)、地沟油W10(10%地沟油生物柴油+90%柴油)与柴油排放污染物的情况。结果表明:有效燃油消耗率(BSFC)随发动机转速... 分析农用拖拉机在高原环境山区道路下行驶时掺烧大豆油B10(10%大豆油生物柴油+90%柴油)、B30(30%大豆油生物柴油+70%柴油)、地沟油W10(10%地沟油生物柴油+90%柴油)与柴油排放污染物的情况。结果表明:有效燃油消耗率(BSFC)随发动机转速升高而降低,而生物柴油油比例的提高会导致BSFC增加。此外,通过发动机功率、燃油消耗量、行驶速度及行驶时间4个方面,对农用拖拉机排放的CO、NO_(x)、CO_(2)及HC的排放因子进行了表征。在CO排放方面,与大豆油B10相比,大豆油B30的生物柴油油比例增加,基于发动机功率的排放因子下降了6.18%。大豆油B10、B30和地沟油W10基于发动机功率的排放因子与柴油相比分别降低了23.66%、24.13%和26.85%。在NO_(x)排放方面,掺烧大豆油B10与地沟油W10时,基于发动机功率的地沟油W10的排放因子比大豆油B10高6.24%;在CO_(2)排放方面,基于燃油消耗量的排放因子显示,大豆油B10、B30和地沟油W10均高于柴油,这表明掺烧生物柴油可促进更充分的燃烧,从而增加CO_(2)排放。在HC排放方面,基于发动机功率的生物柴油HC排放因子值均高于柴油,且基于发动机功率的HC排放因子是《非道路移动源大气污染物排放清单编制技术指南》推荐值1.52倍。随着生物柴油油比例的增加,基于燃油消耗量的HC排放因子也相应增加。 展开更多
关键词 高原环境 山区道路 生物柴油 排放因子 农用拖拉机
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职业性急性高原病的氧疗研究进展
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作者 张玉婷 赵诺 +1 位作者 张智健 张丽娟 《中国急救复苏与灾害医学杂志》 2024年第10期1388-1391,共4页
急性高原病是降低高原作业效率最重要的原因,吸氧是迄今为止缓解急性高原病最为便捷和有效的方法,合理用氧对于顺利开展救援任务至关重要。目前国内外缺乏贴合灾害救援职业特点的氧疗实施标准。本文从生理病理学出发,对职业性急性高原... 急性高原病是降低高原作业效率最重要的原因,吸氧是迄今为止缓解急性高原病最为便捷和有效的方法,合理用氧对于顺利开展救援任务至关重要。目前国内外缺乏贴合灾害救援职业特点的氧疗实施标准。本文从生理病理学出发,对职业性急性高原病的影响因素、氧疗研究现状等进行综述,以期为应急救援人员合理使用高原稀缺的氧疗资源、巩固救治成果提供参考。 展开更多
关键词 急性高原病 高原作业 应急救援 氧吸入疗法 综述
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高原鼠兔筑巢行为形成的裸露斑块对土壤动物多样性的影响
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作者 罗斌 黄智 +3 位作者 禅和霖 颉彩霞 赵景学 臧建成 《草地学报》 CAS CSCD 北大核心 2024年第7期2179-2189,共11页
为探究高原鼠兔筑巢行为对土壤动物多样性的影响,于2022年7月,在念青唐古拉山利用土钻法和干漏斗法进行土壤动物采集和分离,开展高原鼠兔筑巢行为形成的裸露斑块对土壤动物多样性影响的研究。此次调查共采集土壤动物311头,隶属3门,6纲,1... 为探究高原鼠兔筑巢行为对土壤动物多样性的影响,于2022年7月,在念青唐古拉山利用土钻法和干漏斗法进行土壤动物采集和分离,开展高原鼠兔筑巢行为形成的裸露斑块对土壤动物多样性影响的研究。此次调查共采集土壤动物311头,隶属3门,6纲,13目,32科,优势类群为隐颚螨科占所采样本20.26%。与原生草地相比,高原鼠兔筑巢行为形成的裸露斑块中土壤动物类群数、个体数、密度、多样性、丰富度、均匀度均减少,优势类群个体数和优势度则无显著差异。Pearson相关性分析得出土壤动物多样性与植被地上地下生物量、盖度、丰富度、多样性指数、土壤紧实度、土壤湿度呈正相关。结构方程模型进一步表明植被地上地下生物量减少对土壤动物多样性影响最为显著(P<0.01)。因此,高原鼠兔筑巢行为形成的裸露斑块内植被退化和土壤理化性质改变会导致裸露斑块中土壤动物多样性降低。 展开更多
关键词 念青唐古拉山 高原鼠兔 植被 土壤 土壤动物多样性
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青藏高原东北部祁连山一次降水层状云微物理特征的飞机观测研究
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作者 黄颖 付丹红 +1 位作者 郭学良 张文煜 《大气科学》 CSCD 北大核心 2024年第2期539-554,共16页
位于青藏高原东北部的祁连山是石羊河、黑河和疏勒河等多条重要河流的发源地,云微物理特征对于了解该区域大气降水形成过程具有重要作用,但关于祁连山地形云的飞机观测研究很少。本文利用青海省人工影响天气办公室空中国王-350飞机观测... 位于青藏高原东北部的祁连山是石羊河、黑河和疏勒河等多条重要河流的发源地,云微物理特征对于了解该区域大气降水形成过程具有重要作用,但关于祁连山地形云的飞机观测研究很少。本文利用青海省人工影响天气办公室空中国王-350飞机观测数据,分析研究了祁连山2020年8月16日的一次降水层状云的微物理特征。研究表明:祁连山地区此次降水层状云的形成,与偏南气流由低海拔河湟谷地区向高海拔山区运动过程中受地形强迫抬升过程密切相关,云中过冷液态水含量最大值为1.13 g m-3。低海拔山区和高海拔山区的云物理特征有明显差别,低海拔山区由于水汽相对丰富,地形抬升形成的过冷液态水含量较高。山区不同高度粒子形成机制存在显著差异:5600 m(-5.1℃)层过冷液态水含量较高,冰粒子主要通过凝华、聚并生长,也存在弱凇附过程;6560 m(-9.9℃)层存在大量聚合状冰粒子,粒子谱拓宽明显,凝华和聚并过程起主导作用;7850 m(-17.0℃)层基本为冰粒子,存在大量枝状冰粒子聚合体,说明冰粒子以凝华和聚并生长为主。 展开更多
关键词 云微物理结构特征 飞机观测 祁连山 青藏高原东北部
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巨厚高原山地式页岩高频沉积旋回特征与有机质富集机理
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作者 庞鹏 谭秀成 +2 位作者 伍坤宇 邢浩婷 邓伟 《地质论评》 CAS CSCD 北大核心 2024年第S01期27-28,共2页
高频沉积旋回是地球轨道驱动力周期性变化引起海平面升降和气候波动的高频周期性响应(吴怀春等,2011)。同时,高频沉积旋回对有机质富集和储集空间的分布具有重要的控制作用(钟寿康等,2022)。因此,高频沉积旋回分析不仅有利于揭示古气候... 高频沉积旋回是地球轨道驱动力周期性变化引起海平面升降和气候波动的高频周期性响应(吴怀春等,2011)。同时,高频沉积旋回对有机质富集和储集空间的分布具有重要的控制作用(钟寿康等,2022)。因此,高频沉积旋回分析不仅有利于揭示古气候演化、古环境重建和古地貌恢复等重要的基础科学问题,而且能为油气实践勘探提供重要理论指导。柴达木盆地位于青藏高原东北部. 展开更多
关键词 高原山地式页岩 柴达木盆地 高频旋回 古环境重建 有机质富集
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高原健康风险与潜在康养效应研究进展
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作者 范玲玲 尹立 +4 位作者 王式功 张莹 格桑顿珠 李春艳 李景鑫 《中国医药导刊》 2024年第8期755-763,共9页
相较于同纬度平原地区,高原地区属于气候变化敏感区,高原气候平均气温低、降水稀少且集中、相对湿度小、风速大、夏季短或无夏,冬季时期风寒效应显著、常伴有寒潮、沙尘暴、暴雪等极端天气。特别是在全球变暖背景下,高原气候暖湿化日益... 相较于同纬度平原地区,高原地区属于气候变化敏感区,高原气候平均气温低、降水稀少且集中、相对湿度小、风速大、夏季短或无夏,冬季时期风寒效应显著、常伴有寒潮、沙尘暴、暴雪等极端天气。特别是在全球变暖背景下,高原气候暖湿化日益明显,气候季节漂移现象更为显著,研究证实,高原低压缺氧环境会对人体造成不同程度的伤害,与海拔、停留时间、个体差异等因素相关;而适度海拔高度,适当的低压、缺氧高原气候环境,可激发人体活力,提高免疫力和身体机能。鉴于高原气候环境的特殊性以及高原地区医疗资源的相对匮乏,挖掘高原气候环境潜在的康养模式,加强高原康养医学发展建设,对于提高世居高原人群健康水平和降低移居高原人群高原病患病率具有重要意义。本研究在梳理和总结高原气候环境特点、急慢性高原病表现、高原医学(包含高原康养医学)、高原气候环境的潜在康养效应的基础上,探讨高原健康风险与潜在康养效应的国内外研究进展,提出强化高原地区趋利避害的康养理念,加强医疗基础设施建设和人才培养,加强对高原康养医学的宣传和推广,以期为相关科技工作者和广大民众正视高原气候环境对相关人群健康的利弊影响,提高公众对高原康养医学的认知和接受度,进一步为当地气候生态环境资源的挖掘及其健康方面的开发利用提供科学依据,有效保护当地居民和外来游客的身心健康,助力当地旅游经济高质量发展。 展开更多
关键词 高原气候特点 高原病 高原康养医学 研究进展
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基于山区大气电场演变特征与雷电定位数据的雷电临近预警方法
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作者 齐玥 杨庆 +2 位作者 王科 胡逸 徐肖伟 《高电压技术》 EI CAS CSCD 北大核心 2024年第10期4760-4771,共12页
由于高原山区雷暴活动具有尺度小、离散性强的特点,实现山区重点资源区域的雷电灾害准确预警存在较大困难。考虑到雷暴时空演变与地面大气电场特征的关联关系,提出了一种基于大气电场监测数据与实时雷电定位信息的山区雷电临近预警方法... 由于高原山区雷暴活动具有尺度小、离散性强的特点,实现山区重点资源区域的雷电灾害准确预警存在较大困难。考虑到雷暴时空演变与地面大气电场特征的关联关系,提出了一种基于大气电场监测数据与实时雷电定位信息的山区雷电临近预警方法。通过分析典型高原山区不同雷暴发展情况下的大气电场演化特性,发现山区大气电场可作为雷电定位数据的补充源,充分表征雷云剧烈放电和雷暴临近发展的特征信息。在预警过程中,首先将大气电场形态学梯度提取的快速抖动、暂态突变特征与时空匹配的地闪活动特征输入堆叠稀疏自编码器网络模型,判断监测区域附近是否出现雷云放电迹象,再利用雷暴距离变化或者电场波形变化判断雷电活动的临近趋势,最后综合两者的结果完成半径15km监测区域的雷电活动短时预警。在2023年云南山区雷雨季节的雷暴算例分析中,通过双源数据共同提取的山区雷暴活动预警特征的有效识别,可以实现预警准确率为90%,约44%的警报提前时间不小于30 min。 展开更多
关键词 高原山区 大气电场特征 雷电定位数据 雷电临近预警 堆叠稀疏自编码器网络
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四川凉山会东县不同海拔农田土壤phoD基因群落组成及多样性特征
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作者 陈玉蓝 王勇 +4 位作者 梁锦鹏 秦磊涛 魏朝顺 陈强 辜运富 《生态学报》 CAS CSCD 北大核心 2024年第19期8488-8497,共10页
通过分析四川省凉山会东县农田土壤phoD基因群落组成及多样性对不同海拔高度的响应,以期深入认识凉山高原地区不同海拔农田土壤磷素及涉磷微生物群落的分布特点,为建立合理的施肥制度提供科学依据。以凉山州会东县不同海拔高度(1700 m、... 通过分析四川省凉山会东县农田土壤phoD基因群落组成及多样性对不同海拔高度的响应,以期深入认识凉山高原地区不同海拔农田土壤磷素及涉磷微生物群落的分布特点,为建立合理的施肥制度提供科学依据。以凉山州会东县不同海拔高度(1700 m、1900 m、2100 m)土壤为研究对象,通过化学分析和高通量测序技术对土壤理化性质、有机磷组分和含量以及phoD基因群落进行分析。结果表明,pH与海拔高度呈正相关。海拔2100 m的土壤全磷和有效磷含量最高,1900 m的有机磷(OP)、活性有机磷(LOP)、中等活性有机磷(MLOP)和中稳性有机磷(MROP)含量最高,而1700 m海拔的无机磷含量最高。对于不同海拔下的phoD基因群落变化,Shannon指数在高海拔地区最高。同时,3个海拔高度下phoD群落结构差异明显,变形菌门(Proteobacteria)、放线菌门(Actinobacteria)和酸杆菌门(Acidobacteria)是3个海拔高度的主要门类,而慢生根瘤菌(Bradyrhizobium)是低海拔1700 m的主要优势属。土壤pH和总磷(TP)是驱动不同海拔土壤phoD基因群落组成的关键因子。综上,凉山会东高原地区不同海拔高度农田土壤中的phoD基因群落变异明显(P<0.05),且受到土壤pH和总磷的显著影响(P<0.05)。农业生产上应采取因地制宜的施肥措施。 展开更多
关键词 凉山高原 海拔梯度 磷组分 phoD基因群落 多样性
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高原山地环境腹箱式灭火飞机投水数值模拟
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作者 郭曹卓尔 朱培 +1 位作者 邵荃 孙智 《哈尔滨商业大学学报(自然科学版)》 CAS 2024年第5期529-535,共7页
为探究高原山地环境下腹箱式灭火飞机投水着水特性,基于VOF多相流模型构建了飞机投水过程仿真模型,分析地形坡度和海拔高度对地面落水分布的影响,并以投水有效利用率和有效水体覆盖厚度为指标评估其投水效能.结果表明,随山地坡度增加,... 为探究高原山地环境下腹箱式灭火飞机投水着水特性,基于VOF多相流模型构建了飞机投水过程仿真模型,分析地形坡度和海拔高度对地面落水分布的影响,并以投水有效利用率和有效水体覆盖厚度为指标评估其投水效能.结果表明,随山地坡度增加,相同飞行速度下落水地面分布的长度减小而宽度增加,落水区域前端水体分布更密集;随海拔高度增加,相同飞行速度下地面落水分布中后区域更连续,且高原环境下落水地面分布宽度增加但长度变化较小.此外,投水效能普遍随坡度的增加先降低后提高;投水有效利用率在小坡度时随海拔高度增加而提高,其他工况下受海拔高度影响较小,有效水体覆盖厚度普遍随海拔高度增加而降低. 展开更多
关键词 灭火飞机 投水仿真 多相流模型 数值模拟 高原山地环境
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高原山区微型群桩基础承载特征及竖向-水平联合荷载研究
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作者 李海涛 任光明 +3 位作者 冯川 唐杨 王霆 王亮 《长江科学院院报》 CSCD 北大核心 2024年第7期139-147,共9页
为探究高原山区微型群桩基础的承载特性以及水平、竖向荷载耦合作用(V-H联合荷载)的影响,揭示联合荷载相互作用规律,在高原山区微型群桩基础现场试验的基础上,采用FLAC 3D对三种单一荷载情况进行数值反演,并对不同荷载比例下微型群桩基... 为探究高原山区微型群桩基础的承载特性以及水平、竖向荷载耦合作用(V-H联合荷载)的影响,揭示联合荷载相互作用规律,在高原山区微型群桩基础现场试验的基础上,采用FLAC 3D对三种单一荷载情况进行数值反演,并对不同荷载比例下微型群桩基础的V-H联合加载进行模拟。结果表明:①抗压和抗水平试验中,承台效应明显,荷载-位移曲线为“缓变型”;抗拔试验中,曲线为“陡变型”。②联合荷载下,施加水平荷载会削弱桩基竖向承载能力,水平荷载比例较大时,桩身抵抗力矩和桩侧极限摩阻力增大,荷载-上拔位移曲线突变点消失;在竖向荷载的影响下,存在临界荷载比n,下压-水平联合荷载中n 1=3.9,上拔-水平联合荷载中n 2=0.76,荷载比>n时,桩基水平承载力被削弱,<n时,桩基水平承载力提高。③联合荷载下,水平承载力与荷载比的倒数呈四次函数关系,竖向承载力与荷载比的倒数呈二次函数关系;联合荷载下的屈服包络线与单向极限荷载垂线所围空间分为“破坏区”与“安全区”,有别于单向加载的桩基承载特征,且桩基存在一个最优解,使各方向承载力均能得到充分发挥。 展开更多
关键词 微型群桩基础 V-H联合荷载 桩基承载性能 原型试验 数值模拟 高原山区 输变电工程
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