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Differential response of radial growth and δ^(13)C in Qinghai spruce(Picea crassifolia) to climate change on the southern and northern slopes of the Qilian Mountains in Northwest China 被引量:1
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作者 Li Qin Huaming Shang +4 位作者 Weiping Liu Yuting Fan Kexiang Liu Tongwen Zhang Ruibo Zhang 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第3期205-218,共14页
Tree radial growth can have significantly differ-ent responses to climate change depending on the environ-ment.To elucidate the effects of climate on radial growth and stable carbon isotope(δ^(13)C)fractionation of Q... Tree radial growth can have significantly differ-ent responses to climate change depending on the environ-ment.To elucidate the effects of climate on radial growth and stable carbon isotope(δ^(13)C)fractionation of Qing-hai spruce(Picea crassifolia),a widely distributed native conifer in northwestern China in different environments,we developed chronologies for tree-ring widths and δ^(13)C in trees on the southern and northern slopes of the Qilian Mountains,and analysed the relationship between these tree-ring variables and major climatic factors.Tree-ring widths were strongly influenced by climatic factors early in the growing season,and the radial growth in trees on the northern slopes was more sensitive to climate than in trees on the southern.Tree-ring δ^(13)C was more sensitive to climate than radial growth.δ^(13)C fractionation was mainly influenced by summer temperature and precipitation early in the growing season.Stomatal conductance more strongly limited stable carbon isotope fractionation in tree rings than photosynthetic rate did.The response between tree rings and climate in mountains gradually weakened as climate warmed.Changes in radial growth and stable carbon isotope fractionation of P.crassifolia in response to climate in the Qilian Mountains may be further complicated by continued climate change. 展开更多
关键词 Tree rings qinghai spruce(Picea crassifolia Kom.) Stable carbon isotope(δ^(13)C) Qilian Mountains:Climate change
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Present-day movement characteristics of the Qinghai Nanshan fault and its surrounding area from GPS observation
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作者 Yang Liu Yuxuan Qiu +5 位作者 Jialiang Liu Luyun Xiong Caijun Xu Jianghui Geng Gang Zheng Tianchen Sheng 《Geodesy and Geodynamics》 EI CSCD 2024年第2期133-141,共9页
The Qinghai Nanshan fault is a larger fault in the Northeastern Xizang Plateau.In previous studies,its movement characteristics are mainly investigated with geological and seismic observations,and the tectonic transfo... The Qinghai Nanshan fault is a larger fault in the Northeastern Xizang Plateau.In previous studies,its movement characteristics are mainly investigated with geological and seismic observations,and the tectonic transformation role of the fault on its east is not yet clear.This study uses data fusion to obtain denser GPS observations near the Qinghai Nanshan fault.Based on tectonic characteristics,we establish a block model to investigate the fault slip rate,locking degree,and slip deficit.The results show that the Qinghai Nanshan fault slip rate is characterized by sinistral and convergent movement.Both the sinistral and convergent rates display a decreasing trend from west to east.The locking degree and slip deficit are higher in the western segment(with an average of about 0.74 and 1.1 mm/a)and lower in the eastern segment.Then,we construct a strain rate field using GPS observations to analyze the regional strain characteristics.The results indicate that along the fault,the western segment shows a larger shear strain rate and negative dilation rate.Regional earthquake records show that the frequency of earthquakes is lower near the fault.The joint results suggest that the western segment may have a higher earthquake risk.In addition,the insignificant fault slip rate in the eastern segment may indicate that it does not participate in the tectonic transformation among the Riyueshan,Lajishan,and West Qinling faults. 展开更多
关键词 The qinghai Nanshan fault Movement characteristics Block model Slip rate GPS
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Quantification of the concrete freeze–thaw environment across the Qinghai–Tibet Plateau based on machine learning algorithms
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作者 QIN Yanhui MA Haoyuan +3 位作者 ZHANG Lele YIN Jinshuai ZHENG Xionghui LI Shuo 《Journal of Mountain Science》 SCIE CSCD 2024年第1期322-334,共13页
The reasonable quantification of the concrete freezing environment on the Qinghai–Tibet Plateau(QTP) is the primary issue in frost resistant concrete design, which is one of the challenges that the QTP engineering ma... The reasonable quantification of the concrete freezing environment on the Qinghai–Tibet Plateau(QTP) is the primary issue in frost resistant concrete design, which is one of the challenges that the QTP engineering managers should take into account. In this paper, we propose a more realistic method to calculate the number of concrete freeze–thaw cycles(NFTCs) on the QTP. The calculated results show that the NFTCs increase as the altitude of the meteorological station increases with the average NFTCs being 208.7. Four machine learning methods, i.e., the random forest(RF) model, generalized boosting method(GBM), generalized linear model(GLM), and generalized additive model(GAM), are used to fit the NFTCs. The root mean square error(RMSE) values of the RF, GBM, GLM, and GAM are 32.3, 4.3, 247.9, and 161.3, respectively. The R^(2) values of the RF, GBM, GLM, and GAM are 0.93, 0.99, 0.48, and 0.66, respectively. The GBM method performs the best compared to the other three methods, which was shown by the results of RMSE and R^(2) values. The quantitative results from the GBM method indicate that the lowest, medium, and highest NFTC values are distributed in the northern, central, and southern parts of the QTP, respectively. The annual NFTCs in the QTP region are mainly concentrated at 160 and above, and the average NFTCs is 200 across the QTP. Our results can provide scientific guidance and a theoretical basis for the freezing resistance design of concrete in various projects on the QTP. 展开更多
关键词 Freeze–thaw cycles Quantification Machine learning algorithms qinghai–Tibet Plateau CONCRETE
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Origin of the Dashuigou independent tellurium deposit at Qinghai–Xizang Plateau: constraints from the light stable isotopes C, O, and H
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作者 Jianzhao Yin Yuhong Chao +2 位作者 Haoyu Yin Hongyun Shi Shoupu Xiang 《Acta Geochimica》 EI CAS CSCD 2024年第2期385-398,共14页
By studying the light isotopic compositions of carbon,oxygen,and hydrogen,combined with previous research results on the ore-forming source of the deposit,the authors try to uncover its metallogenic origin.The δ^(18)... By studying the light isotopic compositions of carbon,oxygen,and hydrogen,combined with previous research results on the ore-forming source of the deposit,the authors try to uncover its metallogenic origin.The δ^(18)O and δ^(13)C isotope signatures of dolomite samples vary between 10.2 and 13.0‰,and between−7.2 and−5.2‰,respectively,implying that the carbon derives from the upper mantle.δD and δ^(18) O of quartz,biotite,and muscovite from diff erent ore veins of the deposit vary between−82 and−59‰,and between 11.6 and 12.4‰,respectively,implying that the metallogenic solutions are mainly magmatic.According to the relevant research results of many isotope geologists,the fractionation degree of hydrogen isotopes increases as the depth to the Earth’s core increases,and the more diff erentiated the hydrogen isotopes are,the lower their values will be.In other words,mantle-derived solutions can have extremely low hydrogen isotope values.This means that the δD‰ value−134 of the pyrrhotite sample numbered SD-34 in this article may indicate mantle-derived oreforming fl uid of the deposit.The formation of the Dashuigou tellurium deposit occurred between 91.71 and 80.19 Ma. 展开更多
关键词 Carbon oxygen and hydrogen isotopes ORIGIN Independent tellurium deposit The qinghai–Xizang Plateau
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Fluid inclusion and H-O-S-Pb isotope systematics of the Chayong Cu-polymetallic deposit,Sanjiang Metallogenic Belt,Qinghai Province,China
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作者 Jian Wang Hao Wang +3 位作者 Fengyue Sun Fei Wang Xiangwen Li Hongju Yue 《Acta Geochimica》 EI CAS CSCD 2024年第6期1153-1168,共16页
The Chayong Cu-polymetallic deposit is a recently discovered Cu-polymetallic deposit hosted in the Sanjiang Metallogenic Belt within the Tibetan Plateau of China to the northeast of the North Qiangtang terrane.The ore... The Chayong Cu-polymetallic deposit is a recently discovered Cu-polymetallic deposit hosted in the Sanjiang Metallogenic Belt within the Tibetan Plateau of China to the northeast of the North Qiangtang terrane.The ore body occurs in siltstone and is controlled by a northwest-trending fault structure.According to the associations,assemblages,and cutting relationships between ore veins,the hydrothermal mineralization period can be divided into three mineralization stages:(1)a molybdenite mineralization stage,(2)a Cu-polymetallic sulfide stage,and(3)a quartzcarbonate stage.Two types of fluid inclusions(FIs),namely,liquid and vapor-rich inclusions,are present in quartz as so ciated with sulfide minerals.Early-stage FIs are both iquid and vapor-rich,homogenized at temperatures ranging from 364.1 to 384.2℃,and have salinities ranging from0.70%to 9.60%NaCl equivalent(eqv).The middle-stage FIs are also both liquid-and vapor-rich,homogenized at temperatures ranging from 272.4 to 355.6℃,and have salinities ranging from 0.53%-17.10%NaCl eqv.The late-stage FIs are liquid,homogenized at temperatures ranging from 209.4to 255.3℃,and have salinities ranging from 0.35%-6.87%NaCl eqv.The samples from the deposit haveδ^(34)S values of-21.8‰to-19.2‰and-5.5‰to-6.0‰,suggesting that sulfur was derived from the host sediments and magmatic fluids,respectively.The metallic minerals within the deposit have^(206)Pb/^(204)Pb,^(207)Pb/^(204)Pb,and^(208)Pb/^(204)Pb values of 18.439-18.458,15.656-15.679,and 38.772-38.863,respectively,suggesting that the metals were derived from the upper crust and orogenic belts.The samples from the deposit haveδ^(18)O_(W)values of 2.99‰-7.99‰andδD_(W) values ranging from-84.4‰to-73.9‰,indicating that the pre-forming fluids were magmatic and mixed with minor amounts of meteoric water.The ore-forming fluid of the Chayong copper polymetallic deposit was a high-temperature,medium-to low-salinity H_(2)O-NaCl-CH_(4)-N_(2)±CO_(2)fluid system.The early high-temperature magmatic fluid,due to boiling,decreased in temperature,and via the mixing of meteoric water,gradually evolved towards the later-stage medium-to low-temperature and low-salinity fluid,causing nolybdenite mineralization and forming copper polymetallic sulfide veins and quartz carbonate veins. 展开更多
关键词 Fluid inclusions S isotope Pb isotope H-O isotope Chayong Cu-polymetallic deposit Sanjiang Metallogenic Belt YUSHU qinghai
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Spatial-temporal heterogeneity of ecological quality changes across the Qinghai-Tibet Plateau under the influence of climate factors and human activities
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作者 ZiPing Zhang YuWei Cui +1 位作者 WenJia Tang Sen Li 《Research in Cold and Arid Regions》 CSCD 2024年第3期129-140,共12页
Over the last few decades,the ecological quality of the Qinghai–Tibet Plateau(QTP)has significantly changed due to climate warming,humidification,and increasing human activities.Thus,evaluating this region's ecol... Over the last few decades,the ecological quality of the Qinghai–Tibet Plateau(QTP)has significantly changed due to climate warming,humidification,and increasing human activities.Thus,evaluating this region's ecological quality and dominant factors is crucial for sustainable development.In this study,the changes in the ecological quality on the QTP from 2000 to 2020 were evaluated based on aggregated indices and Sen–MK trend analyses,and the dominant factors affecting the ecological quality of the QTP were quantitatively analyzed using decision tree classification.The results revealed that(1)the ecological quality of the QTP exhibited an overall high trend in the east and a low pattern in the west;(2)the ecological quality of the QTP significantly increased from 2000 to 2020,and human activities were the dominant factors causing this change;and(3)the changes in the ecological quality and dominant factors exhibited obvious spatiotemporal heterogeneity.The area with an improved ecological quality occurred mainly in the northern QTP region.It was governed by human activities and precipitation.In contrast,the area with a deteriorated ecological quality occurred largely in the southern QTP region and was dominated by human activities and temperature.The 2000–2010 period was the most significant period of heterogeneity regarding of ecological quality and its driving factors.(4)The change in the ecological quality was mainly affected by the synergistic relationship between human activities and climate change in this region,which encompassed multiple dominant factors.This study provides important information on the spatiotemporal heterogeneity of ecological quality change and its dominant factors on the QTP and offers systematic guidance for the planning and implementation of ecological protection projects. 展开更多
关键词 Remote sensing-based ecological index(RSEI) Dominant factors Synergies and trade-offs qinghai‒Tibet Plateau
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Investigation and Exploitation of New Medicinal Resources of Genus Bupleurum (Umbelliferae) in Qinghai Province and Xizhang (Tibet) Autonomous Region in China 被引量:1
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作者 李颖 郭济贤 +1 位作者 潘胜利 罗达尚 《Journal of Chinese Pharmaceutical Sciences》 CAS 1993年第1期38-44,共7页
In China,some species of Bupleurum (family Umbelliferae) have been used as Chinese traditional medicine under the name “Chai-Hu” for the treatment of fevers and influenza.In the present paper,the authors report a st... In China,some species of Bupleurum (family Umbelliferae) have been used as Chinese traditional medicine under the name “Chai-Hu” for the treatment of fevers and influenza.In the present paper,the authors report a study on the investigation and exploitation of new medicinal resources of “Chai-Hu” in Qinghai Province and Xizang (Tibet) Autonomous Region where no one has studied this hitherto.18 species,7 varieties,I form of Bupleurum and a new species (Bupleurum qinghaiense) have been discovered.The taxonomy and preliminary phytochemical studies of the roots of three medicinal plants,B.qinghaiense,B.rnarginatum var.stenophyllum and B.smithii var.parvifolium.are reported in this paper. 展开更多
关键词 Bupleurum qinghaiense Bupleurum smithii var parvifolium Bupleurum marginatum var stenophyllum Bupleurum spp in qinghai and Xizang
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Impacts and Countermeasures of Climate Change on Animal Husbandry in Qinghai Plateau and Its Surrounding Area 被引量:8
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作者 李红梅 李林 +1 位作者 邓振镛 黎明 《Agricultural Science & Technology》 CAS 2010年第7期138-144,共7页
The paper aims to study the impacts and countermeasures of climate change on animal husbandry in Qinghai plateau and its surrounding area,and evaluate the effect of countermeasures.Results showed that:First,the annua... The paper aims to study the impacts and countermeasures of climate change on animal husbandry in Qinghai plateau and its surrounding area,and evaluate the effect of countermeasures.Results showed that:First,the annual mean temperature,annual mean maximum temperature and annual mean minimum temperature showed an increasing trend in Qinghai plateau during the time from 1961 to 2008; the annual precipitation had not obvious change,but the obvious feature of seasonal change; wind speed and sunshine hours showed a decreasing trend during the time from 1961 to 2008.Secondly,under the current climate condition,grassland productivity showed a decreasing trend,and the grassland theoretical capacity affected by grassland productivity decreased too; warm winter was in favor of livestock overwintering safely,which resulted in a high level of the survival rate of young stock; temperature increasing and precipitation decreasing were beneficial to the fatness of livestock,but the meat yield of livestock was affected by some negative factors such as grassland degradation; livestock diseases had a close relationship with weather condition,and adverse weather condition may arose many diseases of livestock.Thirdly,in view of the current problems of livestock production,we took a series of countermeasures including grass industry construction,livestock improvement,developing new modes of animal husbandry,control and prevention of stockbreeding diseases and insect pests and recovery of meteorological disasters,which played a important role in promoting grassland productivity,solving the problem of the imbalances between livestock and forage,protecting the ecological environment and improving livestock performance. 展开更多
关键词 Climate change qinghai plateau and its surrounding area Animal Husbandry Impact COUNTERMEASURES
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Antibody Detection on Mycoplasma capricolum subsp. Capripneumoniae in Qinghai Province 被引量:3
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作者 赵萍 贺英 +4 位作者 储岳峰 高鹏程 张念章 赵海燕 逯忠新 《Agricultural Science & Technology》 CAS 2010年第8期181-182,共2页
[Objective] The aim was to investigate the prevalence of Mycoplasma capricolum subsp. Capripneumoniae in Qinghai Province. [Method] By using indirect hemagglutination test kit for detecting Mycoplasma capricolum subsp... [Objective] The aim was to investigate the prevalence of Mycoplasma capricolum subsp. Capripneumoniae in Qinghai Province. [Method] By using indirect hemagglutination test kit for detecting Mycoplasma capricolum subsp. Capripneumoniae,208 goat serums were detected. [Result] The positive rate of goat sera was 16.3%,and the positive rate of sera from different regions ranged from 6.7% to 24.3%. [Conclusion] The infection rate of Mycoplasma capricolum subsp. Capripneumoniae was high in Qinghai Province,so it is necessary to strengthen the prevention and control of this disease. 展开更多
关键词 Mycoplasma capricolum subsp. Capripneumoniae Antibody detection qinghai Province
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Impact Assessment of Climate Change on Haidong Agricultural Region in Qinghai and Its Adaptive Countermeasures 被引量:1
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作者 刘彩红 祁贵明 戴升 《Meteorological and Environmental Research》 CAS 2010年第12期3-6,10,共5页
[Objective] The aim was to study climate changes and its effects on agriculture in Haidong agricultural region.[Method] Based on meteorology and agricultural observation data in Haidong agricultural region from 1961 t... [Objective] The aim was to study climate changes and its effects on agriculture in Haidong agricultural region.[Method] Based on meteorology and agricultural observation data in Haidong agricultural region from 1961 to 2009,the characteristics of climate change and its effects on agriculture were analyzed,and the possible effects of future climate change on Haidong agriculture were predicted according to the future climate scenarios provided by down-scaling climate model.[Result] Annual mean temperature in Haidong agricultural region during 1961-2009 showed obvious increase trend,with the rising rate of 0.37 ℃/10 a;annual mean precipitation and annual total sunshine duration went down slightly,with the climatic tendency of 3.70 mm/10 a and-27.55 h/10 a,respectively;climate extreme event occurred less frequently but became severer in recent 49 years.In future 100 years,temperature in Haidong agricultural region would go up significantly,with the slight increase of rainfall,and climate changes would affect agricultural production environment,arrangement,structure and productivity,namely increasing yield fluctuation of agricultural production,cost and investment and changing arrangement and structure.In order to adapt climate change,it was necessary to adjust agricultural structure,strengthen management,improve agricultural infrastructure,adopt new technology,increase the resistance ability of agricultural production to climate change actively and designedly,so as to improve adaptability,furthest reduce loss and realize potential benefit.[Conclusion] Our study could provide references for the decision of government and agricultural sector. 展开更多
关键词 Climate change Agricultural region Effect ASSESSMENT COUNTERMEASURE Haidong in qinghai China
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青海草地早熟禾(Poa pratensis L.cv.Qinghai)近几年的研究进展 被引量:9
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作者 杨时海 马玉寿 +5 位作者 施建军 董全民 王彦龙 王柳英 孙小弟 盛丽 《种子》 CSCD 北大核心 2010年第8期50-52,共3页
论述了青海草地早熟禾(Poa pratensis L.cv.Qinghai)野生栽培品种的由来,以及近几年在生物-生态性、恢复生态学、生理生化和高寒草坪方面的工作,提出了青海草地早熟禾目前依然缺乏的研究,指出今后工作的重点,应加强青藏高原育种工作,寻... 论述了青海草地早熟禾(Poa pratensis L.cv.Qinghai)野生栽培品种的由来,以及近几年在生物-生态性、恢复生态学、生理生化和高寒草坪方面的工作,提出了青海草地早熟禾目前依然缺乏的研究,指出今后工作的重点,应加强青藏高原育种工作,寻找更多更好的牧草生态型品种。 展开更多
关键词 青海草地早熟禾(Poa pratensis L.cv.qinghai) 生物-生态性 生理生化 植被恢复 高寒草坪
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Status quo and Development Strategies for Protected Vegetable Industry in Qinghai Province 被引量:2
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作者 陈来生 李志成 +1 位作者 韩睿 朱为民 《Agricultural Science & Technology》 CAS 2017年第9期1764-1765,共2页
The study introduced protected agriculture development in Qinghai province and concluded its development scale, type and structure, as well as technology supports. Besides, existing problems were proposed such as lowe... The study introduced protected agriculture development in Qinghai province and concluded its development scale, type and structure, as well as technology supports. Besides, existing problems were proposed such as lower production-level, poor equipment, fewer specialized bases, and countermeasures include the following: leading protected agriculture development by macro-control; strengthening market supervision; improving scientific research and innovation to help S & T achievement transformation. 展开更多
关键词 Protected agriculture Status quo Sustainable development qinghai Province
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马流感病毒(A/equine/Qinghai/1/94)核蛋白基因的序列测定及同源性分析 被引量:3
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作者 杨建德 薛飞 +6 位作者 王晓钧 朱远茂 赵立平 吕晓玲 沈荣显 相文华 李景鹏 《中国预防兽医学报》 CAS CSCD 北大核心 2003年第2期96-98,共3页
根据已发表的马流感病毒核蛋白基因序列 ,设计并合成一对特异性引物 ,经反转录_聚合酶链反应 (RT_PCR)成功扩增出了我国马流感病毒 (A/Equine/Qinghai/ 1/ 94 )核蛋白基因 ,将该片段连接到PGEM_T_EASY载体并转化DH5α ,提取阳性菌落的... 根据已发表的马流感病毒核蛋白基因序列 ,设计并合成一对特异性引物 ,经反转录_聚合酶链反应 (RT_PCR)成功扩增出了我国马流感病毒 (A/Equine/Qinghai/ 1/ 94 )核蛋白基因 ,将该片段连接到PGEM_T_EASY载体并转化DH5α ,提取阳性菌落的质粒经EcRo1酶切和PCR鉴定其大小为 1.5kb左右 ,对其测序并进行分析发现 ,与A/Equine /Kentucky/2 / 86、A/Equine/Miami/ 1/ 6 3等关系较近 ,同源率为 93.3%~_97.4 % ,而与我国马流感吉林A/Equine/Jilin/ 1/ 89株关系较远 ,同源率仅为 84 .6 %。 展开更多
关键词 马流感病毒 NP基因 序列测定 同源性分析 核蛋白基因 A/equine/qinghai/1/94
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Analysis to the Driving Force Model and Drives Factor on the Utilized Changes of Cultivated Land in Qinghai Lake Area 被引量:5
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作者 赤旦多杰 淡乐蓉 《Agricultural Science & Technology》 CAS 2009年第6期150-154,共5页
Using path analysis, correlation analysis, partial correlation analysis and system dynamics method to study the driving force of cultivated land in Qinghai Lake Area, and using gradually regression analysis to establi... Using path analysis, correlation analysis, partial correlation analysis and system dynamics method to study the driving force of cultivated land in Qinghai Lake Area, and using gradually regression analysis to establish the driving force model of utilized change of cultivated land. Driving factors, action mechanism and process of utilized change of cultivated land were analyzed, and the differences during all factors were compared. The study provides some decision basis for sustainable utilization and management of land resources in Qinghai Lake Area. 展开更多
关键词 qinghai Lake Area Utilized change of cultivated land Driving force model Driving factors
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Genetic Diversity of SSR Markers in Cultivated Hordeum vulgare L.in Qinghai Province 被引量:1
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作者 田海宁 杨菁 何桂芳 《Agricultural Science & Technology》 CAS 2011年第1期70-73,共4页
[Objective]The aim was to analyze genetic diversity of SSR markers in Hordeum vulgare L.in Qinghai Province and lay a foundation for screening and protecting some excellent H.vulgare cultivars.[Method]SSR markers were... [Objective]The aim was to analyze genetic diversity of SSR markers in Hordeum vulgare L.in Qinghai Province and lay a foundation for screening and protecting some excellent H.vulgare cultivars.[Method]SSR markers were used to evaluate the genetic diversity of 42 cultivated H.vulgare from Qinghai Province.[Result]42 H.vulgare showed polymorphism in 7 SSR markers locus.A total of 24 alleles were identified,and the number of alleles per locus ranged from 1 to 6,with an average of 3.0.According to SSR markers polymorphism,42 H.vulgare could be divided into 4 groups,namely I,II,III and IV.[Result]The study indicated that cultivated H.vulgare from Qinghai Province is rich in genetic diversity,which will provide reference for selecting parent of H.vulgare breeding. 展开更多
关键词 qinghai Province Cultivated Hordeum vulgare L. SSR markers Genetic diversity
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Changes of Organic Carbon in Soil under Different Land Use Patterns in Alpine Agricultural Region of Qinghai 被引量:14
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作者 李月梅 《Agricultural Science & Technology》 CAS 2010年第2期124-127,共4页
Using organic carbon density grouping method,the change trends of soil total organic carbon(SOC),light fraction content and light fraction organic carbon under 4 land use patterns of returning cultivated land to fores... Using organic carbon density grouping method,the change trends of soil total organic carbon(SOC),light fraction content and light fraction organic carbon under 4 land use patterns of returning cultivated land to forest(cropland,artificial forest,inter-cropping of forest and grassland and original sample plot)in alpine agricultural region of Qinghai were studied.The content of SOC was in order:intercropping of forest and grassland > original sample plot > artificial forest > cropland.There was signi... 展开更多
关键词 qinghai Returning cultivated land to forest Soil organic carbon Light fraction organic carbon
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Effect of Irrigation on Groundwater Dynamic Change in the Typical Irrigated Area of Qinghai Province 被引量:2
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作者 周鸿文 吕文星 +2 位作者 唐红波 王永峰 申国峰 《Agricultural Science & Technology》 CAS 2016年第7期1718-1722,共5页
Under the influence of the natural and human factors, water table of irri- gated area Changes frequently, but it is mainly affected by irrigation water infiltration replenishment during the irrigation. 5 groundwater o... Under the influence of the natural and human factors, water table of irri- gated area Changes frequently, but it is mainly affected by irrigation water infiltration replenishment during the irrigation. 5 groundwater observation wells were constructed in experimental plot of the Daxia irrigated area to carry out the experiment of the effect of irrigation on groundwater dynamic change in this research. The results showed that the groundwater stage dynarnic change rule of spring and seedling irri- gation stage in the typical plot was fit to the hydrological geology condition of grade- I terrace of Huangshui river valley. On the whole, lateral canal water direction formed a line effect. The No. 1 and No. 2 observation well were the closest to the lateral canal, which received more supplies, and the water level was the highest; the No, 3 observation well took the second place; The No. 4 and No. 5 observation well accepted least supplies, and the water level was the lowest. The rangeability of water table of spring irrigation period was significantly higher than that of seedling irrigation period, this is mainly due to the difference value of intake water volume and drainage water volume of spring irrigation phase was significantly higher than the seedling irrigation phase. 展开更多
关键词 Farm irrigation Water table Dynamiq Change Typical irrigated area basin in qinghai Province
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Analysis of the distribution characteristics of ^(226)Ra and ^(228)Ra and their sources in the western part of Qinghai Lake 被引量:3
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作者 孔凡翠 沙占江 +5 位作者 杜金洲 苏维刚 于晨光 赵顺利 胡菊芳 冶梅 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第6期1402-1412,共11页
The ^226Ra and ^228Ra activities of Qinghai Lake surface water, groundwater, river water, suspended particles, and bottom sediments were measured in a gamma-ray spectrometer. The sources of ^226Ra and ^228Ra were disc... The ^226Ra and ^228Ra activities of Qinghai Lake surface water, groundwater, river water, suspended particles, and bottom sediments were measured in a gamma-ray spectrometer. The sources of ^226Ra and ^228Ra were discussed according to their distribution characteristics. ^226Ra and ^228Ra activities (dpm/(100 L)) ranged from 14.13±0.22 to 19.22±0.42 and 17.724-0.66 to 30.96:kl.47 in the surface water of the North Bay, respectively, and from 7.88±0.24 to 33.80±0.47 and 15.73±0.74 to 57.31±1.44, respectively, in the South Bay. The surface water near the estuary had a lower salinity and had a higher concentration of radium isotopes than the samples collected further away. The farther offshore the sample, the higher the salinity was, and the lower the radium isotope activity. The distribution of radium activities in the western part of Qinghai Lake is controlled by several factors, including Buha River runoff, desorption from suspended particles derived from the river, groundwater discharge, and a small amount of diffusion from the sediment. 展开更多
关键词 ^226RA ^228Ra surface water of qinghai lake groundwater river water qinghai Lake
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A Comprehensive Evaluation of Tourism Climate Suitability in Qinghai Province, China 被引量:11
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作者 TANG Chengcai ZHONG Linshen +1 位作者 KRISTEN McDonald CHENG Shengkui 《Journal of Mountain Science》 SCIE CSCD 2012年第3期403-413,共11页
Qinghai Province is an important component of the Qinghai-Tibet Plateau in China. Scientific evaluation of the suitability of Qinghai's climate for tourism can contribute to overcoming obstacles posed by climate o... Qinghai Province is an important component of the Qinghai-Tibet Plateau in China. Scientific evaluation of the suitability of Qinghai's climate for tourism can contribute to overcoming obstacles posed by climate on sustainable tourism development in Qinghai Province, including disparities between the low and high seasons, high altitude health concerns, and weather events. A tourism climate suitability evaluation model of the Qinghai-Tibet Plateau is constructed (Tourism Climate Suitability Index, or TCSI), and tourism climate suitability is comprehensively evaluated for Qinghai Province from climate data from 1960 to 2009. Results show that: (I) There is clear distributional characteristics of spatial-temporal variability of TCSI values in Qinghai Province. (II) Tourism climate suitability in Qinghai Province has significant seasonal and regional differences. The year is divided into a very suitable period (July and August), suitable tourism periods (from April and October), less suitable periods (From Nov to Mar). June to August is the most suitable tourism period in Qinghai. Qinghai Province is divided into five levels of tourism climate suitability: most suitable regions, very suitable regions, suitable regions, less suitable regions, and unsuitable region. (III) The key factor which influences regional differences in tourism climatic suitability is atmospheric oxygen. And the key factors which chiefly influence seasonal differences of tourism climate suitability are temperature and humidity, the wind chill factor, and barrier weather. 展开更多
关键词 Tourism climate Tourism climatesuitability index (TCSI) Comprehensive evaluation qinghai Province qinghai-Tibet Plateau China
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Serological Investigation on Mycoplasma Oviovipneumoniae in Qinghai Province
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作者 郭晗 储岳峰 +5 位作者 赵萍 高鹏程 贺英 冯晓明 樊祜卿 逯忠新 《Animal Husbandry and Feed Science》 CAS 2009年第4期34-35,共2页
[ Objective] To investigate the prevalence of Mycoplasma oviovipneurnoniae in Qinghai Province. [ Method] With positive indirect hemagglutination test kit for detecting antibodies against Mycoplasma oviovipneumoniae, ... [ Objective] To investigate the prevalence of Mycoplasma oviovipneurnoniae in Qinghai Province. [ Method] With positive indirect hemagglutination test kit for detecting antibodies against Mycoplasma oviovipneumoniae, 965 sheep sera and 208 goat sera were collected in Qinghai Province from 2006 to 2008 and detected. [ Result ] The positive rate of sheep sera and goat sera was 30.4% and 19.7%, respectively. The posi- tive rate of sheep sera collected from different regions ranged from 19.7% to 40.2%, and that of goat sere ranged from 6.6% to 22.2%. In addition, the incidence in winter and spring was higher than that in summer and autumn. [ Conclusion ] The infection rate of Mycoplasrna ovipneumoniae should be higher in Qinghai region than in other western regions, so it is necessary to strengthen the prevention and control of this disease. 展开更多
关键词 Mycoplasma ovipneumoniae Antibody detection Serological investigation qinghai Province
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