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Variations in rare earth elements with environmental factors in lake surface sediments from 17 lakes in western china

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Journal of Mountain Science 2021年第7期18卷 1811-1822页

作者： DU Ding-ding CHEN Liu-qin BAI Yong-hui HU Hai-ping School of Earth Sciences East China University of TechnologyNanchang 330013China State Key Laboratory of Nuclear Resources and Environment Nanchang 330013China School of Earth Sciences Lanzhou UniversityLanzhou 730000China

Numerous lakes in western china are excellent sites for understanding environmental ***,what dominates rare earth element(REE) variations are still under debate in the lake environmental *** this study,we selected 28 surface sediment samples from 17 lakes(*** lakes,small water bodies,etc.) in the QinghaiTibet Plateau and Xinjiang *** samples were analyzed to reveal the behavior of the REEs and major *** REE patterns are characterized by light rare earth element(LREE) enrichment,weak Ce anomaly(0.84-0.98,0.94 on average) and negative Eu anomaly(0.53-1.00,0.67 on average).The homogeneous REE patterns may reflect similar REE of the source ***,the REE abundances showed some significant *** this study,water chemistry data analyses inferred that the highly REE values appear possibly in the saltwater lake,and also related to carbonate mineral,whereas p H played a minor role in REE *** large-scale lakes(*** Bosten and Lake Ulungur),the results showed that the relatively larger REE values are in the margins of ***,lower REE contents are towards the central *** study suggested that five major factors control the REE contents:(1) The REE tends to increase with the increase of the weathering intensity.(2) Likewise,heavy mineral(***,anatase,zircon,etc.) are probably primary in these sediments because they are highly enriched in the REE.(3) The contribution of Fe-Mn oxides is significant in sediments because their concentrations highly correlate with the REE.(4) The carbonate mineral(mainly calcite) played a significant role on the REE values in the lakes because the REEs are incorporated into the carbonate minerals generating the low REE concentrations.(5) Major element analysis,mineral analysis,and grain-size data analysis showed that the REE distribution is chiefly influenced by finer grain-size component of lake sediments due to the decreasing propor

关键词： western china Lake surface sediments Rare earth elements Environmental factors

Social Effect of Environmental Pollution on Valley-cities in western china

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Chinese Geographical Science 2009年第1期19卷 8-16页

作者： QU Tao ZHANG Yun LIU Ran DONG Mali Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beij＇ing 100101 China Beijing Normal University Beijing 100875 China

Accompanied with the acceleration of urbanization and industrialization,the large and medium-scale valley-cities in the western china are facing environmental problems at respective levels in common. The urban environmental pollution causes economic losses,and also brings out negative effects on urban society. Based on the social investigation method,this paper aims to study the harms to urban society brought by environmental pollution. After the investigation to the inhabitants of six typical valley-cities:Lanzhou,Xining,Chongqing,Baiyin,Luzhou and Zigong,we found that the urban environmental pollution has resulted in negative influences with different levels on residents' physical,psychological,work,recreations,studies and social activities. The problem of environmental pollution has become a serious restriction to sustainable development of cities mentioned above. Herewith,it has become urgent to strengthen the government regulations for controlling urban environmental pollution.

关键词： valley-city environmental pollution social effect western china

Evaluation of boron isotopes in halite as an indicator of the salinity of Qarhan paleolake water in the eastern Qaidam Basin, western china

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Geoscience Frontiers 2019年第1期10卷 253-262页

作者： Yongsheng Du Qishun Fan Donglin Gao Haicheng Wei Fashou Shan Binkai Li Xiangru Zhang Qin Yuan Zhanjie Qin Qianhui Ren Xueming Teng Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources Qinghai Institute of Salt Lakes Chinese Academy of Sciences Key Laboratory of Salt Lake Geology and Environment of Qinghai Province University of Chinese Academy of Sciences Tianjin Center China Geological Survey

In this study, nineteen brine samples from the Qarhan Salt Lake(QSL) in western china were collected and analyzed for boron(B) and chlorine(Cl) concentrations, total dissolved solids(TDS), pH values and stable B isotopic compositions. The B concentrations and δ^(11) B values of brines in the QSL range from 51.6 mg/L to138.4 mg/L, and from +9.32& to +13.08&, respectively. By comparison of B concentrations and TDS of brines in QSL with evaporation paths of brackish water, we found that B enrichment of brines primarily results from strong evaporation and concentration of Qarhan lake water. Combining with comparisons of B concentrations, TDS, p H values and δ^(11) B values of brines, previously elemental ratios(K/Cl, Mg/Cl, Ca/Cl, B/Cl) and δ^(11) B values of halite from a sediment core(ISL1 A), we observe good correlations between B concentrations and TDS, TDS and pH values, pH and δ^(11) B values of brines, which demonstrate that higher B concentrations and more positive δ^(11) B values of halite indicate higher salinity of the Qarhan paleolake water as well as drier paleoclimatic conditions. Based on this interpretation of the δ^(11) B values of halite in core ISL1 A, higher salinity of the Qarhan paleolake occurred during two intervals, around 46-34 ka and26-9 ka, which are almost coincident with the upper and lower halite-dominated salt layers in core ISL1 A,drier climate phases documented from the δ^(18) O record of carbonate in core ISL1 A and the paleomoisture record in monsoonal central Asia, and a higher solar insolation at 30°N. These results demonstrate that the δ^(11) B values of halite in the arid Qaidam Basin could be regarded as a new proxy for reconstructing the salinity record of paleolake water as well as paleoclimate conditions.

关键词： B isotope compositions Brine Chemical concentrations Qarhan salt lake western china Salinity of paleolake water

The Norian megalodontid fauna in Qinghai-Tibet Plateau,western china

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Science china Earth Sciences 2012年第10期55卷 1620-1626页

作者： YAO HuaZhou ZHANG RenJie SHA JingGen WANG JianXiong NIU ZhiJun DUAN QiFa Wuhan Institute of Geology and Mineral Resources China Geological Survey Wuhan 430223 China Nanjing Institute of Geology and Paleontology Chinese Academy of Sciences Nanjing 210008 China

Many well-preserved silicified megalodontids found from the Jiapila Formation of the Upper Triassic in western china show great variations in the amorphous teeth and the massive hinge plate,making the internal molds vary greatly in size and ***,the internal molds of megalodontids do not always provide reliable taxonomic *** a result,about 3/4 of the 132 species and 6 of 9 genera of Triassic Megalodontidae erected on the basis of internal molds have to be *** revised definitions of genera Neomegalodon,Triadomegalodon,and Conchodon are given in this paper.

关键词： Qinghai-Tibet Plateau western china Norian megalodontids

Cross-border Urban Networks Based on Manufacturing Global Value Chain:A Study of Listed Companies in western china

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Chinese Geographical Science 2023年第6期33卷 1033-1052页

作者： MAN Shan YANG Yongchun ZENG Tonggang WANG Meimei College of Earth and Environmental Sciences Lanzhou UniversityLanzhou730000China Key Laboratory of western china’s Environmental Systems Ministry of Education of the People’s Republic of ChinaLanzhou UniversityLanzhou730000China

Cross-border investment is essential for western china’s *** value chain(GVC)forms cross-border investment networks between industries in western china and overseas *** on GVC,this study uses the social network analysis method,entropy method,multi-index comprehensive evaluation method,and quadratic assignment procedure analysis method to examine the characteristics and influencing factors of the urban networks of research and development(R&D),production,and sales formed as a result of the overseas investments of listed manufacturing companies in western *** showed that the three types of investment networks involved multiple industry types and multiple central cities with differentiated diversity and *** R&D urban network’s leading sub-industries were the mechanical equipment and instruments,medicine and biological products,and metal and nonmetal *** destination cities were mostly those home to educational and scientific research *** production urban network’s leading sub-industries were the mechanical equipment,instrument,and food and beverage *** destination cities were mostly regional central cities in developing *** sales urban network’s leading sub-industries were the mechanical equipment and instrument,metal and nonmetal,and petrochemical and plastics *** destination cities were numerous and *** addition,the R&D urban network easily formed specialized clusters,core nodes easily controlled the production urban network,and individual nodes did not easily control the sales urban *** and economic system advantages greatly impacted the three network *** the different influencing factors,this study suggests optimizing the institutional investment environment to narrow the institutional gap,adjusting and optimizing the investment layout to expand overseas markets,and increasing R&D funds to stimulate technological progress

关键词： manufacturing industry Global value chain(GVC) overseas investment cross-border networks western china

Estimation of glacier ice storage in western china constrained by field ground-penetrating Radar surveys

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Advances in Climate Change Research 2022年第3期13卷 359-374页

作者： Peng-Bin LIANG Li-De TIAN Institute of International Rivers and Eco-Security Yunnan UniversityKunming 650500China Yunnan Key Laboratory of International Rivers and Transboundary Eco-security Kunming 650091China

Recent decades have witnessed the accelerated retreat of alpine glaciers,which likely portends a decline in the glacial ice melt on which large downstream populations rely for ***,estimating water storage in alpine glaciers is critical for predicting the trend of glacier *** study compiled a rich set of ice thickness observations for glaciers of varying sizes in western *** here presented a first-order assessment of the various errors involved in interpreting ice thickness from ground-penetrating radar(GPR)*** empirical Bayesian kriging(EBK)method was used for ice thickness interpolation and volume *** then established a new volume-scaling law specific to western china glaciers based on these 36 volume-area *** together with the Second Chinese Glacier Inventory(SCGI),we obtain a regional volume estimate of 4451±298 km^(3).By comparison,we believed that this result is the most reliable estimate of the total ice storage in western china and more reliably predicts gross glacier ***,our results show that the method of glacier division can strongly affect the total volume estimation,which previous studies *** emphasizes the need for more surveyed glaciers data and more accurate glacier inventory to improve the evaluation of the climate impact on glacier melting water resources and to help ensure the future survival of these alpine glaciers.

关键词： Ground-penetrating radar Glacier thickness survey Glacier volume volume-area scaling law Distributed model western china

Granitic Magmatism in Eastern Tethys Domain(western china) and their Geodynamic Implications

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Acta Geologica Sinica(English Edition) 2022年第2期96卷 401-415页

作者： LAI Shaocong ZHU Renzhi QIN Jiangfeng ZHAO Shaowei ZHU Yu State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi’an 710069China

western china locates in the eastern section of the Tethys domain, granitic rocks in this region with variable formation ages and geochemistry record key information about the crust-mantle structure and thermal evolution during the convergent process of Tethys. In this study, we focus on some crucial granitic magmatism in the western Yangtze, Qinling orogen, and western Sanjiang tectonic belt, where magma sequence in the convergent orogenic belt can provide important information about the crust-mantle structure, thermal condition and melting regime that related to the evolution processes from Pre-to Neo-Tethys. At first, we show some features of Pre-Tethyan magmatism, such as Neoproterozoic magmatism(ca. 870–740 Ma) in the western margin of the Yangtze Block were induced by the assembly and breakup of the Rodinia supercontinent. The complication of voluminous Neoproterozoic igneous rocks indicated that the western Yangtze Block underwent the thermodynamic evolution from hot mantle-cold crust stage(ca. 870–850 Ma) to hot mantle and crust stage(ca. 850–740 Ma). The Neoproterozoic mantle sources beneath the western Yangtze Block were progressively metasomatized by subduction-related compositions from slab fluids(initial at ca. 870 Ma), sediment melts(initial at ca. 850 Ma), to oceanic slab melts(initial at ca. 825–820 Ma) during the persistent subduction process. Secondly, the early Paleozoic magmatism can be well related to three distinctive stages(variable interaction of mantle-crust to crustal melting to variable sources) from an Andeans-type continental margin to collision to extension in response to the evolution of ProtoTethys and final assembly of Gondwana continent. Thirdly, the Paleo-Tethys magmatism, Triassic granites in the Qinling orogenic display identical formation ages and Lu-Hf isotopic compositions with the related mafic enclaves, indicate a coeval melting event of lower continental crust and mantle lithosphere in the Triassic convergent process and a

关键词： granitic magmatism geodynamic western china eastern Tethys

Drivers of the Severity of the Extreme Hot Summer of 2015 in western china

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Journal of Meteorological Research 2018年第6期32卷 1002-1010页

作者： Wei CHEN Buwen DONG State Key Laboratory of Numerical Modelling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of Sciences National Centre for Atmospheric Science Department of Meteorology University of Reading

western china experienced an extreme hot summer in 2015,breaking a number of temperature *** summer mean surface air temperature(SAT)anomaly was twice the interannual *** hottest daytime temperature(TXx)and warmest night-time temperature(TNx)were the highest in china since *** extreme hot summer occurred in the context of steadily increasing temperatures in recent *** carried out a set of experiments to evaluate the extent to which the changes in sea surface temperature(SST)/sea ice extent(SIE)and anthropogenic forcing drove the severity of the extreme summer of 2015 in western *** results indicate that about 65%–72% of the observed changes in the seasonal mean SAT and the daily maximumand daily minimum(Tmin)temperatures over western china resulted from changes in boundary forcings,including the SST/SIE and anthropogenic *** the relative role of individual forcing,the direct impact of changes in anthropogenic forcing explain about 42% of the SAT warming and 60%(40%)of the increase in TNxand Tmin(TXxand Tmax)in the model *** changes in SST/SIE contributed to the remaining surface warming and the increase in hot extremes,which are mainly the result of changes in the SST over the Pacific Ocean,where a super El Ni?o event *** study indicates a prominent role for the direct impact of anthropogenic forcing in the severity of the extreme hot summer in western china in 2015,although the changes in SST/SIE,as well as the internal variability of the atmosphere,also made a contribution.

关键词： severity of temperature extremes summer 2015 western china anthropogenic forcing

Assessment on the Effects of Hepatitis B Prevention and Control Measures in western china:A Comparison of Three Population-based Serosurveys

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Biomedical and Environmental Sciences 2020年第10期33卷 735-744页

作者： CHEN Hui LIU Nan JI Zhao Hua PU Zhong Shu GUO Zhi Wen GAO Jie SHAO Zhong Jun LIU Yi Wen YAN Yong Ping Department of Epidemiology School of Public HealthAir Force Medical UniversityXi'an 710032ShaanxiChina Wuwei municipal Center for Disease Control and Prevention Wuwei 733000GansuChina

Objective Despite the remarkable progress in efforts to control disease spread,the nationwide elimination of hepatitis B in china is still hindered by the persistently high rate of hepatitis B virus(HBV)infection in western *** study aimed to evaluate the strategy of hepatitis B prevention and control in western china and identify potential areas and strategies for *** Susceptible population vaccination,health education,professional training of doctors,and other prevention and control measures have been implemented in Wuwei city since *** were obtained from three representative cross-sectional serosurveys conducted in 2010,2013,and *** serum samples were subjected to enzyme-linked immunosorbent assays to detect the following seromarkers:HBV surface antigen(HBsAg),antibody against hepatitis B surface antigen(anti-HBs),and antibody against hepatitis B core antigen(anti-HBc).Estimates of variance were determined using Taylor series linearization *** The three serosurveys revealed decreases in the prevalence of HBsAg(7.19% in 2010 vs.6.51% in 2013 vs.5.87% in 2015)and anti-HBc positivity(43.89%vs.32.87%vs.28.46%)and an increase in the prevalence of anti-HBs positivity(49.07%vs.53.66%vs.53.72%)over *** 2010 to 2015,the legally reported incidence of hepatitis B in Wuwei city decreased from 686.53/100,000 to 53.72/100,***,persistently high HBsAg-positive rates(above 5.40%)were observed among subjects aged 20–69 years old in the three serosurveys;the prevalence of HBsAg was above 1% among children younger than 10 years ***,rural subjects had higher rates of HBsAg and anti-HBc positivity than their urban counterparts(6.04%vs.4.83% and 30.26%vs.20.35%,respectively)in 2015 but had a lower rate of anti-HBs positivity(49.68 vs.55.18%).Multivariate regression analysis showed that age,urban and rural areas,and education level were the main factors affecting HBV *** Although vaccine-based preve

关键词： Hepatitis B Prevention a n d control measures Serosurvey western china