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Continental drift, plateau uplift, and the evolutions of monsoon and arid regions in Asia, Africa, and Australia during the Cenozoic
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作者 Xiaodong LIU Buwen DONG +2 位作者 Zhi-Yong YIN Robin S. SMITH Qingchun GUO 《中国科学:地球科学英文版》 SCIE EI CAS CSCD 2019年第7期1053-1075,共23页
Monsoon and arid regions in the Asia-Africa-Australia (A-A-A) realm occupy more than 60% of the total area of these continents. Geological evidence showed that significant changes occurred to the A-A-A environments of... Monsoon and arid regions in the Asia-Africa-Australia (A-A-A) realm occupy more than 60% of the total area of these continents. Geological evidence showed that significant changes occurred to the A-A-A environments of the monsoon and arid regions, the land-ocean configuration in the Eastern Hemisphere, and the topography of the Tibetan Plateau (TP) in the Cenozoic. Motivated by this background, numerical experiments for 5 typical geological periods during the Cenozoic were conducted using a coupled ocean-atmosphere general circulation model to systemically explore the formations and evolutionary histories of the Ceno zoic A-A-A monso on and arid regions un der the influences of contine ntal drift and plateau uplift. Results of the nu merical experime nts indicate that the timings and causes of the formations of monsoon and arid regi ons in the A-A-A realm were very different. The northern and southern African monsoons existed during the mid-Paleocene, while the South Asian monsoon appeared in the Eocene after the Indian Subcontinent moved into the tropical Northern Hemisphere. In contrast, the East Asian mon soon and northern Australian monso on were established much later in the Miocene. The establishment of the tropical monsoons in northern and southern Africa, South Asia, and Australia were determined by both the continental drift and seas onal migratio n of the In ter-Tropical Convergence Zone (ITCZ), while the position and height of the TP were the key factor for the establishment of the East Asian monsoon. The presence of the subtropical arid regions in northern and southern Africa, Asia, and Australia depended on the positions of the continents and the control of the planetary scale subtropical high pressure zones, while the arid regions in the Arabian Peninsula and West Asia were closely related to the retreat of the Paratethys Sea. The formation of the mid-latitude arid region in the Asian interior, on the other hand, was the consequence of the uplift of the TP. These results from this study provide insi 展开更多
关键词 CENOZOIC MONSOON REGION ARID REGION Continental drift Tibetan Plateau UPLIFT Climate simulation
Impact of climate change on allowable bearing capacity on theQinghai-Tibetan Plateau 预览
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作者 XU Xiao-Ming WU Qing-Bai 《气候变化研究进展:英文版》 CSCD 2019年第2期99-108,共10页
Climate change has a substantial impact on infrastructures in the permafrost on the Qinghai-Tibetan Plateau (QTP). In this study, the mean annual ground temperature (MAGT) and permafrost evolution were investigated in... Climate change has a substantial impact on infrastructures in the permafrost on the Qinghai-Tibetan Plateau (QTP). In this study, the mean annual ground temperature (MAGT) and permafrost evolution were investigated in both the historical (1950-2005) and projected (2006-2099) periods. Then, an allowable bearing capacity model was used to discuss the allowable bearing capacity change on the QTP. Results show that the MAGT increased by 0.36 ℃ during 1950-2005. The MAGT will increase by 0.40 (RCP2.6), 0.79 (RCP4.5), 1.07 (RCP6.0), and 1.75 (RCP8.5)℃C during 2006-2099. In addition, the permafrost area has decreased by 0.195 × 10^6 km2 in 1950-2005. The permafrost area will decrease by 0.232 × 10^6 (RCP2.6), 0.468 × 10^6 (RCP4.5), 0.564 × 10^6 (RCP6.0), and 0.803 × 10^6 (RCP8.5) km2 during 2006-2099. With the degradation of permafrost, the allowable bearing capacity in permafrost zones would decrease accordingly. The decreasing trend is 6 kPa per 10 years in 1950-2005, and will be 0.6 (RCP2.6), 5 (RCP4.5), 7 (RCP6.0), and 11 (RCP8.5) kPa per 10 years during 2006-2099. The most remarkable trend would be observed under RCP8.5. Meanwhile, some scientific advices for the design, construction, operation and maintenance of permafrost engineering in the context of climate change were provided. 展开更多
关键词 Qinghai-Tibetan PLATEAU CLIMATE CHANGE PERMAFROST Allowable BEARING capacity
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高原环境下一氧化碳对人体的毒性研究初探 预览
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作者 索朗巴珍 朱士宽 《生物化工》 2019年第4期84-85,91共3页
西藏拉萨市平均海拔为3650m,空气中年平均含氧量占平原地区含氧量的64.3%。拉萨市空气含氧量呈明显的季节变化趋势,冬季是一年中市空气含氧量最低的季节,仅占平原地区含氧量的63.3%。冬季又是一氧化碳中毒案件的高发期。本文通过收集201... 西藏拉萨市平均海拔为3650m,空气中年平均含氧量占平原地区含氧量的64.3%。拉萨市空气含氧量呈明显的季节变化趋势,冬季是一年中市空气含氧量最低的季节,仅占平原地区含氧量的63.3%。冬季又是一氧化碳中毒案件的高发期。本文通过收集2016年至2019年3月拉萨市发生的一氧化碳中毒死亡案件,对21例中毒死亡者的血样分析结果进行统计分析,结果:男性12例、女性9例,年龄19~60岁,液化气(或煤气)中毒5例,其余均为煤炭中毒。通过分析21个中毒死亡者血样的HbCO%水平测定结果,发现HbCO%的平均值大于50%。 展开更多
关键词 高原 一氧化碳 人体 HbCO%
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Quantitative indicative significance of pollen assemblages on vegetation coverage in deciduous Quercus forest in the central Loess Plateau, China
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作者 Yuanhao SUN Shengrui ZHANG +5 位作者 Qinghai XU Yiwen LI Wei SHEN Tao WANG Zhongze ZHOU Ruchun ZHANG 《中国科学:地球科学英文版》 SCIE EI CAS CSCD 2019年第6期992-1001,共10页
We compared the pollen assemblages of surface moss samples and corresponding vegetation inventory data from 34 sites in the Huangling region of the central Loess Plateau. Our aims were to determine the characteristics... We compared the pollen assemblages of surface moss samples and corresponding vegetation inventory data from 34 sites in the Huangling region of the central Loess Plateau. Our aims were to determine the characteristics of the pollen assemblages from the deciduous broadleaved forest climax community and its significance in terms of vegetation type and species composition. The pollen assemblages are dominated by woody plants such as Quercus(42% of total terrestrial pollen),Betula(16%) and Pinus(12%), with minor differences between different plant communities. The pollen assemblages of individual sampling sites differed from the vegetation composition within the 0–100 m scope and were more similar to the vegetation coverage within the 0–1000 m scope. This indicates that the surface pollen assemblages mainly reflect the comprehensive information from the vegetation composition of a large area, rather than the vegetation composition close to the sampling site. The contents of Quercus, Betula and Pinus pollen are high, and close to their vegetation coverage;whereas the contents of deciduous broadleaved arbor taxa(such as Malus and Acer) are lower, but their corresponding regional vegetation cover is higher. This suggests that the vegetation information conveyed by poorly-represented pollen taxa should be considered when interpreting stratigraphic pollen assemblages. Using the observed quantitative relationships between pollen and vegetation of the main taxa, we reconstructed the regional vegetation composition in the Gonghai Lake area of the northeastern Loess Plateau during the middle Holocene(7300–5000 yr BP). The results indicated that Quercus-dominated deciduous broadleaved forest climax community developed in the mountains surrounding the lake. 展开更多
关键词 Loess Plateau DECIDUOUS broadleaved FOREST CLIMAX community POLLEN assemblage Absolute vegetation coverage
Outcome of complex tibial plateau fractures with Ilizarov external fixation with or without minimal internal fixation
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作者 Koushik Narayan Subramanyam Madhusudhan Tammanaiah +2 位作者 Abhishek Vasant Mundargi Ritesh Nilakanthrao Bhoskar Patllola Siddharth Reddy 《中华创伤杂志:英文版》 CAS CSCD 2019年第3期166-171,共6页
Purpose: To evaluate the clinico-radiological outcome of complex tibial plateau fractures treated with Ilizarov external fixation with or without minimal internal fixation. Methods: This retrospective review was condu... Purpose: To evaluate the clinico-radiological outcome of complex tibial plateau fractures treated with Ilizarov external fixation with or without minimal internal fixation. Methods: This retrospective review was conducted on all the cases of Schatzker types V and VI tibial plateau fractures treated by Ilizarov external fixation between July 2006 and December 2015 with the minimum follow-up duration of one year. There were 30 patients: 24 males and 6 females, mean age 43.33 years, and mean follow-up 3.6 years. Three of them were open fractures;15 cases were Schatzkertype V fractures and the other 15 type VI. According to AO/OTA classification, there were 11 type C1, 12 C2 and 7 type C3 fractures. Outcome assessment was made with American Knee Society Score (AKSS) and Rasmussen's Radiological Score (RRS) at final follow-up. Results: Out of the 30 cases, mini-open reduction was performed in 7, bone graft in 4, minimal internal fixation in 10 and knee temporary immobilisation in 11 patients. Mean duration of external fixation was 11.8 weeks. All fractures united. Pin tract infections in 7 and common peroneal neuropathy in 2 patients were self-limiting. Two patients had axial misalignment of less than 10°. At final follow-up, the mean knee range of motion was 114.7, mean AKSS 81.5 and mean RRS 16.7. On statistical analysis, Schatzker type of fractures, use of minimal internal fixation and knee-spanning did not influence the final outcome. Conclusion: Ilizarov external fixator with or without minimal internal fixation provides acceptable outcome for complex tibial plateau fractures. Care must be taken to look for minor loss of alignment, especially in Type VI Schatzker fractures after removal of the fixator. However small sample size precludes firm conclusions. 展开更多
关键词 TIBIAL plateau FRACTURES Schatzker's classification ILIZAROV techniques Ring FIXATOR
次仁加布:我的人生从一场梦开始 预览
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作者 Cheng Yao(Text/Photo) 《中国西藏:英文版》 2019年第4期63-70,共8页
I did not know how far it was between Tsonyi County and NagquTown until I checked the map: a whopping 520 kilometers! Located in the northwestern area of the northern Tibet and inside the Changtang National Nature Res... I did not know how far it was between Tsonyi County and NagquTown until I checked the map: a whopping 520 kilometers! Located in the northwestern area of the northern Tibet and inside the Changtang National Nature Reserve, Tsonyi is the county standing upon the highest plateau of the world. The place was once known as "No Man's Land" due to it as well as Hoh Xil to the north being so unfrequently visited? 展开更多
关键词 TIBET PLATEAU COUNTY Uninhabited LAND
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An Untouched Natural Paradise 预览
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作者 JIAO FENG 《今日中国:英文版》 2019年第6期74-77,共4页
HOH Xil Nature Reserve,“Hoh Xil” meaning ‘beautiful girl’ in Mongolian, is located in the hinterland of the Qinghai-Tibet Plateau. Because of its harsh natural environment, no people live here. Therefore it’s als... HOH Xil Nature Reserve,“Hoh Xil” meaning ‘beautiful girl’ in Mongolian, is located in the hinterland of the Qinghai-Tibet Plateau. Because of its harsh natural environment, no people live here. Therefore it’s also known as the “forbidden zone for humans” or “mysterious land.” It is one of the regions on earth that humans have little knowledge of, thus preserving it as an untouched natural paradise. Located in the northeastern corner of the Qinghai- Tibet Plateau, Hoh Xil Nature Reserve covers a large area of mountains and grassland at an altitude of more than 4,500 meters above sea level. 展开更多
关键词 NATURAL PARADISE Qinghai-Tibet PLATEAU
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高原缺氧暴露对大鼠海马组织HIF-1α表达的影响 预览
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作者 李晓琳 李茂星 陶文迪 《解放军医药杂志》 CAS 2019年第10期1-5,共5页
目的探讨模拟不同高原缺氧暴露海拔和时间对大鼠海马组织HIF-1α表达的影响。方法选取72只SPF级雄性Wistar大鼠,随机分为常氧空白组、缺氧3000 m、4500 m、6000 m、7500 m和8000 m组,每组12只,常氧空白组置于兰州(海拔1500 m)常氧环境,... 目的探讨模拟不同高原缺氧暴露海拔和时间对大鼠海马组织HIF-1α表达的影响。方法选取72只SPF级雄性Wistar大鼠,随机分为常氧空白组、缺氧3000 m、4500 m、6000 m、7500 m和8000 m组,每组12只,常氧空白组置于兰州(海拔1500 m)常氧环境,其余5组分别置于低压低氧动物实验舱中进行不同海拔的缺氧暴露;缺氧暴露12 h后,观察海马组织病理学变化,检测HIF-1α蛋白表达情况。根据该次实验结果来固定海马组织损伤以及HIF-1α表达最为明显的缺氧暴露海拔,进一步将72只SPF级雄性Wistar大鼠随机分为常氧空白组、缺氧6 h、12 h、24 h、36 h、72 h组。常氧空白组置于兰州(海拔1500 m)常氧环境,其余5组分别置于低压低氧动物实验舱中在7500 m海拔下进行不同时间的缺氧暴露,观察海马组织病理学变化,检测HIF-1α蛋白表达情况。结果随着缺氧海拔升高,海马组织病理损伤及HIF-1α表达逐渐升高,7500 m时达到最高点(P<0.01);随着缺氧时间延长,海马组织病理损伤及HIF-1α表达逐渐升高(P<0.01),24 h后达到一个平台期。结论随着缺氧海拔升高以及缺氧时间延长,海马组织中HIF-1α表达逐步增高,7500 m缺氧>24 h可以作为稳定的兰州地区大鼠缺氧损伤模型。 展开更多
关键词 缺氧诱导因子-1 高原 缺氧海拔 缺氧时间 海马组织 大鼠
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The Carbon Isotope Fluctuations across the Lower–Middle Jurassic Boundary and the Paleoclimate Changes 预览
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作者 YI Haisheng XIA Guoqing +5 位作者 LI Gaojie YI Fan ZHANG Shuai CAI Zhanhu JIAO Haijing WU Chihua 《地质学报:英文版》 SCIE CAS CSCD 2019年第1期244-245,共2页
The Qiangtang Basin of Tibetan Plateau most widely outcrops marine Jurassic strata in China,even in eastern Asian,and the Jurassic strata and ammonites’occurrence are in favor of researching evolution of paleoceanogr... The Qiangtang Basin of Tibetan Plateau most widely outcrops marine Jurassic strata in China,even in eastern Asian,and the Jurassic strata and ammonites’occurrence are in favor of researching evolution of paleoceanography in the Tethyan region and global stratigraphic comparison.This work focused on the carbon isotope changes across the J I–J 2 boundary in the eastern Tethys region. 展开更多
关键词 CARBON STRATA Plateau marine CARBON most
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柴油机装车实际高原环境应用特征分析及验证用试验循环开发 预览
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作者 冀树德 杨天军 +6 位作者 刘逢春 唐智 孔祥鑫 杨文影 魏鹏程 贾晓亮 康佐明 《车用发动机》 北大核心 2019年第3期46-51,共6页
以三型柴油机为对象,基于跟踪记录的道路载荷数据,分析了柴油机装车在实际高原环境条件行驶呈现的主要特征,并就台架验证不充分的问题设计了高原台架模拟的试验循环。结果表明,柴油机在海拔4300m以上实际高原环境地区的运行主要集中在... 以三型柴油机为对象,基于跟踪记录的道路载荷数据,分析了柴油机装车在实际高原环境条件行驶呈现的主要特征,并就台架验证不充分的问题设计了高原台架模拟的试验循环。结果表明,柴油机在海拔4300m以上实际高原环境地区的运行主要集中在中高转速中高负荷区域,运行转速、排气温度、冷却水温度等参数存在较为严重的超限行为,其中柴油机冷却水温约70%以上时间处于超限状态。此外,柴油机主要工作在大于50%输出功率的区间,高原使用时增压比偏大。设计的高原台架模拟试验循环为600s的瞬态试验循环,可表征柴油机装车后高原使用时的运行行为。 展开更多
关键词 柴油机 高原 运行特征 试验循环
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Anthropogenic Aerosol Pollution over the Eastern Slope of the Tibetan Plateau 预览
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作者 Rui JIA Min LUO +4 位作者 Yuzhi LIU Qingzhe ZHU Shan HUA Chuqiao WU Tianbin SHAO 《大气科学进展:英文版》 SCIE CAS CSCD 2019年第8期847-862,共16页
In this study, a combination of satellite observations and reanalysis datasets is used to analyze the spatiotemporal distribution, classification and source of pollutants over the eastern slope of the Tibetan Plateau(... In this study, a combination of satellite observations and reanalysis datasets is used to analyze the spatiotemporal distribution, classification and source of pollutants over the eastern slope of the Tibetan Plateau(ESTP). The aerosol optical depth(AOD) over the ESTP is extremely large and even larger than some important industrialized regions and deserts. The main aerosol component over the ESTP is sulfate, followed by carbonaceous and dust aerosols. Local emissions related to human activity directly contribute to the accumulation of sulfate and carbonaceous aerosols over the Sichuan Basin. In addition, in spring, abundant carbonaceous aerosols emitted from forest, grassland and savanna fires in Southeast Asia can be transported by the prevailing southwesterly wind to southern China and the ESTP. The dust AOD over the ESTP peaks in spring because of the transport from the Taklimakan and Gobi deserts. Additionally, the high aerosol loading over the ESTP is also directly related to the meteorological background. Due to the special topography, the terrain-driven circulation can trap aerosols in the Sichuan Basin and these aerosols can climb along the ESTP due to the perennial updraft. The aerosol loading is lowest in summer because of effective wet deposition induced by the strong precipitation and better dispersion conditions due to the larger vertical temperature gradients and ascending air movement enhanced by the plateau heat pump effect. In contrast,the aerosol loading is greatest in winter. Abundant anthropogenic aerosols over the ESTP may generate some climatic and environmental risks and consequently greatly influence the downstream regions. 展开更多
关键词 eastern SLOPE of the TIBETAN PLATEAU ANTHROPOGENIC AEROSOLS dust
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Highland County Now Famed for Fruits and Vegetables 预览
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作者 NAN BEIBAO 《今日中国:英文版》 2019年第8期60-63,共4页
THE Sichuan-Tibet Highway runs across the Litang Plateau, drawing a beautiful curve on the vast Maoyaba grassland.“Forty years ago, having vegetables was a luxury for us in Litang. We were unable to grow vegetables o... THE Sichuan-Tibet Highway runs across the Litang Plateau, drawing a beautiful curve on the vast Maoyaba grassland.“Forty years ago, having vegetables was a luxury for us in Litang. We were unable to grow vegetables owing to the technological backwardness of our area. We also had difficulties in transporting them here from inland parts of the country because of poor road conditious, and for a very few of them which were available here in the market, they were very expensive,” recalled Luorong Zeren, 51, deputy director of the Litang County Bureau of Agriculture. 展开更多
关键词 Highland COUNTY Now Famed FRUITS and VEGETABLES the Litang PLATEAU
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驻西南高原地区空军某部官兵2017年夏季军事训练伤调研 预览
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作者 叶超群 于东睿 +3 位作者 王广云 王向荣 张向阳 吉保民 《空军医学杂志》 2019年第4期300-302,323共4页
目的了解驻西南高原地区空军某部2017年夏季军事训练伤发病特点,为卫勤保障工作提供参考。方法对驻西南高原地区空军某部官兵2017年6-9月间就诊的官兵病例资料,按照《军事训练伤诊断标准及防治原则》分类统计,并按照国际疾病分类方法(IC... 目的了解驻西南高原地区空军某部2017年夏季军事训练伤发病特点,为卫勤保障工作提供参考。方法对驻西南高原地区空军某部官兵2017年6-9月间就诊的官兵病例资料,按照《军事训练伤诊断标准及防治原则》分类统计,并按照国际疾病分类方法(ICD-10)对其按部位、疾病种类进行统计;并对常驻官兵和短期驻训官兵的资料进行对比分析。结果 2017年夏季驻西南高原地区空军某部官兵中,最常见军事训练伤为软组织损伤,构成比为79.58%,关节损伤为13.32%;其中,常驻部队官兵软组织损伤构成比明显高于短期驻训组(P<0.05),但关节损伤明显低于短期驻训组;发病部位以腰部最常见占30.83%,其次依次为颈27.29%,下肢25.83%;常驻官兵颈部伤病构成比明显高于短期驻训组(P<0.05),而下肢伤病明显低于短期驻训组(P<0.01);最常见训练伤为腰痛30.83%,其次为颈痛26.67%;常驻组颈痛构成比明显高于短期驻训组(P<0.05);踝扭伤明显低于短期驻训组(P<0.05)。结论 2017年夏季驻西南高原地区空军某部军事训练伤发病率较高,其中软组织损伤发病率最高,伤部较多发生在腰部、其次为颈部、下肢;对常驻和短期驻训官兵的训练应行针对性指导。 展开更多
关键词 军事训练伤 空军 西南 高原 常驻 短期驻训
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Review on simulation of land-surface processes on the Tibetan Plateau 预览
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作者 Rui Chen MeiXue Yang +1 位作者 XueJia Wang GuoNing Wan 《寒旱区科学:英文版》 CSCD 2019年第2期93-115,共23页
The Tibetan Plateau (TP) has powerful dynamics and thermal effects, which makes the interaction between its land and atmosphere significantly affect climate and environment in the regional or global area. By retrospec... The Tibetan Plateau (TP) has powerful dynamics and thermal effects, which makes the interaction between its land and atmosphere significantly affect climate and environment in the regional or global area. By retrospecting the latest research progress in the simulation of land-surface processes (LSPs) over the past 20 years, this study discusses both the simulation ability of land-surface models (LSMs) and the modification of parameterization schemes from two perspectives, the models' applicability and improved parameterization schemes. Our review suggests that different LSMs can well capture the spatiotemporal variations of the physical quantities of LSPs;but none of them can be fully applied to the plateau, meaning that all need to be revised according to the characteristics specific to the TP. Avoiding the unstable iterative computation and determining the freeze?thaw critical temperature according to the thermodynamic equilibrium equation, the unreasonable freeze?thaw parameterization scheme can be improved. Due to the complex underlying surface of the TP, no parameterization scheme of roughness length can well simulate the various characteristics of the turbulent flux over the TP at different temporal scales. The uniform soil thermodynamic and hydraulic parameterization scheme is unreasonable when it is applied to the plateau, as a result of the strong soil heterogeneity. There is little research on the snow-cover process so far, and the improved scheme has no advantage over the original one due to the lack of some related physical processes. The constant interaction among subprocesses of LSPs makes the improvement of a multiparameterization scheme yield better simulation results. According to the review of existing research, adding high-quality observation stations, developing a parameterization scheme suitable for the special LSPs of the TP, and adjusting the model structures can be helpful to the simulation of LSPs on the TP. 展开更多
关键词 TIBETAN PLATEAU land - ATMOSPHERE interaction LAND-SURFACE models model APPLICABILITY parameterized MODIFICATION
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The Tibetan Plateau Surface–Atmosphere Coupling System and Its Weather and Climate Effects: The Third Tibetan Plateau Atmospheric Science Experiment
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作者 Ping ZHAO Yueqing LI +26 位作者 Xueliang GUO Xiangde XU Yimin LIU Shihao TANG Wenming XIAO Chunxiang SHI Yaoming MA Xing YU Huizhi LIU La JIA Yun CHEN Yanju LIU Jian LI Dabiao LUO Yunchang CAO Xiangdong ZHENG Junming CHEN An XIAO Fang YUAN Donghui CHEN Yang PANG Zhiqun HU Shengjun ZHANG Lixin DONG Juyang HU Shuai HAN Xiuji ZHOU 《气象学报:英文版》 SCIE CSCD 2019年第3期375-399,共25页
The Tibetan Plateau(TP) is a key area affecting forecasts of weather and climate in China and occurrences of extreme weather and climate events over the world. The China Meteorological Administration, the National Nat... The Tibetan Plateau(TP) is a key area affecting forecasts of weather and climate in China and occurrences of extreme weather and climate events over the world. The China Meteorological Administration, the National Natural Science Foundation of China, and the Chinese Academy of Sciences jointly initiated the Third Tibetan Plateau Atmospheric Science Experiment(TIPEX-Ⅲ) in 2013, with an 8–10-yr implementation plan. Since its preliminary field measurements conducted in 2013, routine automatic sounding systems have been deployed at Shiquanhe, Gaize, and Shenzha stations in western TP, where no routine sounding observations were available previously. The observational networks for soil temperature and soil moisture in the central and western TP have also been established. Meanwhile, the plateau-scale and regional-scale boundary layer observations, cloud–precipitation microphysical observations with multiple radars and aircraft campaigns, and tropospheric–stratospheric air composition observations at multiple sites, were performed. The results so far show that the turbulent heat exchange coefficient and sensible heat flux are remarkably lower than the earlier estimations at grassland, meadow, and bare soil surfaces of the central and western TP. Climatologically, cumulus clouds over the main body of the TP might develop locally instead of originating from the cumulus clouds that propagate northward from South Asia. The TIPEX-Ⅲ observations up to now also reveal diurnal variations, macro-and microphysical characteristics, and water-phase transition mechanisms, of cumulus clouds at Naqu station. Moreover, TIPEX-Ⅲ related studies have proposed a maintenance mechanism responsible for the Asian "atmospheric water tower" and demonstrated the effects of the TP heating anomalies on African, Asian, and North American climates. Additionally, numerical modeling studies show that the Γ distribution of raindrop size is more suitable for depicting the TP raindrop characteristics compared to the M–P distribution, the o 展开更多
关键词 TIBETAN PLATEAU field observation data processing WEATHER and climate numerical forecasting
Impact of Surface Potential Vorticity Density Forcing over the Tibetan Plateau on the South China Extreme Precipitation in January 2008. Part Ⅰ:Data Analysis
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作者 Tingting MA Guoxiong WU +2 位作者 Yimin LIU Zhihong JIANG Jiahui YU 《气象学报:英文版》 SCIE CSCD 2019年第3期400-415,共16页
The external source/sink of potential vorticity (PV) is the original driving force for the atmospheric circulation. The relationship between surface PV generation and surface PV density forcing is discussed in detail ... The external source/sink of potential vorticity (PV) is the original driving force for the atmospheric circulation. The relationship between surface PV generation and surface PV density forcing is discussed in detail in this paper. Moreover, a case study of the extreme winter freezing rain/snow storm over South China in January 2008 is performed, and the surface PV density forcing over the eastern flank of the Tibetan Plateau (TP) has been found to significantly affect the precipitation over South China in this case. The TP generated PV propagated eastward in the middle troposphere. The associated zonal advection of positive absolute vorticity resulted in the increasing of cyclo-nic relative vorticity in the downstream region of the TP. Ascending air and convergence in the lower troposphere developed, which gave rise to the development of the southerly wind. This favored the increasing of negative meridio-nal absolute vorticity advection in the lower troposphere, which provided a large-scale circulation background conducive to ascending motion such that the absolute vorticity advection increased with height. Consequently, the ascending air further strengthened the southerly wind and the vertical gradient of absolute vorticity advection between the lower and middle troposphere in turn. Under such a situation, the enhanced ascending, together with the moist air transported by the southerly wind, formed the extreme winter precipitation in January 2008 over South China. 展开更多
关键词 potential VORTICITY DENSITY (PVD) ABSOLUTE VORTICITY advection TIBETAN Plateau winter precipitation
Analysis of vegetation changes and dominant factors on the Qinghai-Tibet Plateau, China 预览
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作者 HongWei Wang Yuan Qi +3 位作者 ChunLin Huang XiaoYing Li XiaoHong Deng JinLong Zhang 《寒旱区科学:英文版》 CSCD 2019年第2期150-158,共9页
This research was undertaken to clarify the characteristics of vegetation change and its main influencing factors on the Qinghai-Tibet Plateau. Using the greenness rate of change (GRC) and correlation factors, we anal... This research was undertaken to clarify the characteristics of vegetation change and its main influencing factors on the Qinghai-Tibet Plateau. Using the greenness rate of change (GRC) and correlation factors, we analyzed the trend of vegetation change and its dominant factors from 2000 to 2015. The results indicate that the vegetation tended to improve from 2000 to 2015 on the Qinghai-Tibet Plateau, with the improved area accounting for 39.93% of the total;and the degraded area accounting for 19.32%. The areas of degraded vegetation are mainly concentrated in the low-relief and intermediate- relief mountains of the high-altitude and extremely high-altitude areas on the Qinghai-Tibet Plateau, as the vegetation characteristics are impacted by the terrain. Temperature and precipitation have obvious response mechanisms to vegetation growth, but the effects of precipitation and temperature on vegetation degradation are not significant over a short time frame. Overgrazing and population growth are the dominant factors of vegetation degradation on the Qinghai-Tibet Plateau. 展开更多
关键词 Qinghai-Tibet PLATEAU REMOTE SENSING VEGETATION activity degraded DOMINANT factors
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Multi-scale spatial relationships between soil total nitrogen and influencing factors in a basin landscape based on multivariate empirical mode decomposition
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作者 ZHU Hongfen CAO Yi +3 位作者 JING Yaodong LIU Geng BI Rutian YANG Wude 《干旱区科学:英文版》 SCIE CSCD 2019年第3期385-399,共15页
The relationships between soil total nitrogen(STN)and influencing factors are scale-dependent.The objective of this study was to identify the multi-scale spatial relationships of STN with selected environmental factor... The relationships between soil total nitrogen(STN)and influencing factors are scale-dependent.The objective of this study was to identify the multi-scale spatial relationships of STN with selected environmental factors(elevation,slope and topographic wetness index),intrinsic soil factors(soil bulk density,sand content,silt content,and clay content)and combined environmental factors(including the first two principal components(PC1 and PC2)of the Vis-NIR soil spectra)along three sampling transects located at the upstream,midstream and downstream of Taiyuan Basin on the Chinese Loess Plateau.We separated the multivariate data series of STN and influencing factors at each transect into six intrinsic mode functions(IMFs)and one residue by multivariate empirical mode decomposition(MEMD).Meanwhile,we obtained the predicted equations of STN based on MEMD by stepwise multiple linear regression(SMLR).The results indicated that the dominant scales of explained variance in STN were at scale 995 m for transect 1,at scales 956 and 8852 m for transect 2,and at scales 972,5716 and 12,317 m for transect 3.Multi-scale correlation coefficients between STN and influencing factors were less significant in transect 3 than in transects 1 and 2.The goodness of fit root mean square error(RMSE),normalized root mean square error(NRMSE),and coefficient of determination(R2)indicated that the prediction of STN at the sampling scale by summing all of the predicted IMFs and residue was more accurate than that by SMLR directly.Therefore,the multi-scale method of MEMD has a good potential in characterizing the multi-scale spatial relationships between STN and influencing factors at the basin landscape scale. 展开更多
关键词 INTRINSIC MODE function MULTIVARIATE empirical MODE decomposition MULTI-SCALE spatial relationship sampling TRANSECT soil total nitrogen Chinese LOESS Plateau
Intraperitoneal injection adenovirusPmultirnai-ldhcOkay Plateau pika (Ochotona curzoniae) Skeletal MuscleLdhcGene of Silence effect 预览
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作者 Yangzhi Deng 《探索-植物与动物科学》 2019年第1期25-29,共5页
Intraperitoneal injection is a kind of simple and convenient to drug of style in order to verify intraperitoneal injection adenovirusPmultirnai-ldhcThe plateau pika (Ochotona curzoniae (Ochotona curzoniac) Skeletal Mu... Intraperitoneal injection is a kind of simple and convenient to drug of style in order to verify intraperitoneal injection adenovirusPmultirnai-ldhcThe plateau pika (Ochotona curzoniae (Ochotona curzoniac) Skeletal MuscleLdhcGene Silence of feasibility will27Only plateau pika (Ochotona curzoniae) divided into interference group, Shell Group and blank control group each group9Only individual interference group and Shell Group respectively Injection0.65 mLAdenovirusPmultirnai-ldhcAnd adenovirusPmultirnai-NSBlank control group injected with the same amount of physiological saline injection after7/dDetection Skeletal Muscle inLdhcGeneMRNAAnd protein of Expression Level Determination the lactate dehydrogenase (LDH) Activity and lactic acid (LD) And three phosphoric acid adenosine (ATP) Of content. Results show that and blank control group compared interference group inMRNAAND PROTEIN LEVEL,LdhcGene expression respectively reduce41.73%And15.76%;Lactate dehydrogenase (LDH) Activity, lactic acid (LD) AndATPContent respectively reduce23.98%,51.08%And19.29%. Results (intraperitoneal injection adenovirusPmultirnai-ldhcCan effective silence Skeletal Muscle inLdhcGene expression. 展开更多
关键词 INTRAPERITONEAL injection plateau pika LACTATE dehydrogenase LACTIC ACID three phosphoric ACID adenosine
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高原核桃采穗圃营建技术试验 预览
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作者 廖东 刘小利 +1 位作者 乔维范 耶芳芳 《青海大学学报:自然科学版》 2019年第3期34-40,共7页
为满足核桃良种推广需求,解决高原地区穗条成熟时间晚于嫁接时间的供需矛盾,以辽宁1号核桃良种建立采穗圃,研究了采穗母株截顶定干、短截促萌和肥水管理对穗条促成的影响。结果表明:采穗母树定植后截顶定干,萌芽率和成枝率分别可达83.45... 为满足核桃良种推广需求,解决高原地区穗条成熟时间晚于嫁接时间的供需矛盾,以辽宁1号核桃良种建立采穗圃,研究了采穗母株截顶定干、短截促萌和肥水管理对穗条促成的影响。结果表明:采穗母树定植后截顶定干,萌芽率和成枝率分别可达83.45%和85.14%。第二年春季萌动时对主枝进行留桩15 cm短截,可作接穗枝的长度和比率分别达54.47 cm和89.43%。采穗前追施复合肥和氮肥2~3次以上,枝条长度可达121.67 cm,粗度达1.21 cm,可作接穗枝的长度达77.40 cm,每公顷产量达12 510条,穗条促成效果明显。对采穗圃中采穗母株产穗能力和穗条质量进行比较,明确了高原核桃采穗圃穗条促成条件。 展开更多
关键词 高原 辽宁1号核桃 采穗圃 营建
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