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Impacts of permafrost changes on alpine ecosystem in Qinghai-Tibet Plateau

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Science china Earth {1. 2006年第11期49卷 1156-1169页

作者： wang Genxu1,3., li Yuanshou2 , WU Qingbai2 & wang Yibo3.1. {3. of Mountain Hazards and Environment, chinese academy of sciences, Chengdu 610041, china 2. cold and arid regions environmental and Engineering research {3., chinese academy of sciences,{13., china 3. Resource and Environment School, lanzhou University,{13., china 1. institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China 3. Resource and Environment School Lanzhou University Lanzhou 730000 China 2. cold and {1. regions {3. and Engineering research institute Chinese Academy of Sciences Lanzhou 730000 China

Alpine cold ecosystem with permafrost environment is quite sensitive to c{1.matic changes and the changes in permafrost can significantly affect the alpine ecosystem. The vegetation coverage, grassland biomass and soil nutrient and texture are selected to indicate the regime of alpine cold ecosystems in the Qinghai-Tibet Plateau. The interactions between alpine ecosystem and permafrost were investigated with the depth of active layer, permafrost thickness and mean annual ground temperature (MAGTs). Based on the statistics model of GPTR for MAGTs and annual air temperatures, an analysis method was developed to analyze the impacts of permafrost changes on the alpine ecosystems. Under the c{1.mate change and human engineering activities, the permafrost change and its impacts on alpine ecosystems in the permafrost region between the Kunlun Mountains and the Tanggula Range of Qinghai-Tibet Plateau are studied in this paper. The results showed that the per- mafrost changes have a different influence on different alpine ecosystems. With the increase in the thickness of active layer, the vegetation cover and biomass of the alpine cold meadow exhibit a significant conic reduction, the soil organic matter content of the alpine cold meadow ecosystem shows an exponential decrease, and the surface soil materials become coarse and gravelly. The alpine cold steppe ecosystem, however, seems to have a relatively weak relation to the permafrost environment. Those relationships resulted in the fact that the distribution area of alpine cold meadow decreased by 7.98% and alpine cold swamp decreased by 28.1.% under the permafrost environment degradation during recent 1. years. In the future 50 years the alpine cold meadow ecosystems in different geomorphologic units may have different responses to the changes of the permafrost under different c{1.mate warming conditions, among them the alpine cold meadow and swamp ecosystem located in the low mountain and plateau area will have a relatively

关键词： permafrost environment, alpine cold ecosystem, statistics relationship, climate change, impacts, Qinghai-Tibet Plateau.

Vertical quantitative and dominant population distribution of the bacteria isolated from the Muztagata ice core

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Science china Earth {1. 2005年第10期48卷 1728-1739页

作者： XIANG Shurong1, YAO Tandong1, 2, AN lizhe1, 3. WU Guangjian2, XU Baiqing2, MA Xiaojun 3. li Zhen1, {3. Junxia1 & YU Wusheng1 1. Key Laboratory of Ice Core and cold regions Environment, cold and arid regions environmental and Engineering research institute, chinese academy of sciences,{13., china 2. institute of Tibetan Plateau research, chinese academy of sciences, Beijing 100085, china 3. College of life Science, lanzhou University,{13., china Key Laboratory of Ice Core and cold {1. Environment Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China institute of Tibetan Plateau {1. chinese academy of sciences Beijing{3. College of life Science {1. University {1.{3.

Vertical distribution of the main bacteria isolated from the Muztagata ice core (about 22.4 m) was investigated by means of cultivation and 1.S rRNA sequence analysis. The results showed that the amount of culturable bacteria fluctuated with ice core depth, and was more in dirty layer than in clean ice, which suggested the close corresponding relationship between high input of the bacteria deposited by wind and snowflow and dirty layer. Most of the bacteria were psychrophiles and psychrotolerants, including α- and γ-proteobacteria, Cryobacterium psychro-philum, CFB (Cytophaga-Flavobacterium-Bacteroides) group, high-G+C gram-positive bacteria (HGC). Acinetobacter sp. and HGC repeatly occurred in different ice depths, and their quantita-tive distribution was consistent with the change of the total amount of culturable bacteria with depth, which suggested the main bio-indicator; while Flavobacterium, Cryobacterium psychro-philum, and α-proteobacteria, also functioned as a secondary indicator of climatic and environ-mental changes. This study is the first report concerning continuous quantitative variation and pattern of the main culturable bacteria in ice core section.

关键词： Pamirs Plateau, ice core, pattern of bacteria, bio-indicator.

Development of a chinese land data assimilation system:its progress and prospects

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Progress in Natural Science:Materials International 2007年第8期17卷 881-892页

作者： li Xin~(1**) Huang Chunlin~1 Che Tao~1 Jin Rui~1 wang Shugong~l wang Jiemin~1 Gao Feng~1 Zhang Shuwen~2 Qiu Chongjian~2 wang Chenghai~2 (1.cold and arid regions environmental and Engineering research institute,chinese {13. of sciences,lanzhou 73.000,china 2.College of Atmospheric sciences,lanzhou University,lanzhou 73.000,china) [a]cold and {1. regions {3. and Engineering research institute Chinese Academy of Sciences Lanzhou China [b]College of Atmospheric sciences Lanzhou University Lanzhou China

The objective of land data assimilation is to merge multi-source observations into the dynamics of land surface model for improving the estimation of land surface *** have developed a land data assimilation system for china's land *** this sys- tem,the Common Land Model and Simple Biosphere Model 2 are used to simulate land surface *** radiative transfer models of thawed and frozen soil,snow,lake,and vegetation are used as observation operators to transfer model predictions into estimated bright- ness temperatures.A Monte-Carlo based sequential filter,the ensemble Kalman filter,is implemented as data assimilation method to inte- grate mode{1.ng and *** system is capable of assimilating passive microwave remotely sensed data such as special sensor mi- crowave/imager (SSM/I),TRMM microwave imager (TMI),and advanced microwave scanning radiometer enhanced for EOS (AMSR- E) and the conventional in situ measurements of soil and snow.A spatiotemporally consistent assimilated dataset for soil moisture,soil temperature,snow and frozen soil,with a spatial resolution of 0.25 degree and temporal resolution of one hour,has been *** paper introduces the development of chinese land data assimilation system and the progress made on data assimilation algorithms,land sur- face mode{1.ng,microwave remote sensing of land surface hydrological variables,and the preparation of atmospheric forcing *** dis- tinct characteristics and challenges of developing land data assimilation system and the perspectives for future development are also dis- cussed.

关键词： land data assimilation land surface model passive microwave remote sensing Kalman filter

Effects of sunspot cycle length and CO_2 on air temperature along Qinghai-Xizang railway and air temperature's trend prediction

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Science china Earth {1. 2004年第z1期47卷 131-141页

作者： li Dongliang, QUO Hui, wang Wen & WEI licold & arid regions environmental and Engineering research institute, chinese academy of Science, lanzhou 73.000,{13. Department of Atmospheric sciences, lanzhou University, lanzhou 73.000,{13. 1. cold & {1. {3. environmental and Engineering research institute Chinese Academy of Science 730000 Lanzhou China2. Department of Atmospheric Sciences Lanzhou University 730000 Lanzhou China

There are well coherences between annual averaged air temperatures at every meteorological station along the Qinghai-Xizang railway, and its 1.-year moving average correlation coefficient is 0.92. Thus, the regional averaged annual mean temperature series along the Qinghai-Xizang railway (Trw) from 1.3. to 2000 are constructed. The investigation is suggested that: Trw had significant responses to the 5-year lagged sunspot cycle length (SCL) and 1.-year lagged concentration of atmospheric carbon dioxide (CO2), and the correlation coefficients between them are -0.76 (SCL) and 0.88 (CO2), respectively. The future SCL is predicted by the model of average generated function constructed with its main cycles of 76a, 93., 1.8a, 205a and 275a. The result shows that the SCL would be becoming longer in the first half of the 21.t century, and then it could be becoming shorter in the second half of the 21.t century. Based on the natural change of SCL and the effect of double CO2 concentration, Trw in the 21.t century is forecasted. It could warm up about 0.50℃ in the first half of the 21.t century compared with the last decade of last century. The mean maximum air temperature could be likely about 0.20℃ in July and from 0.40℃ to 1.1.℃ in January. The annual air temperature difference would likely reduce 0.3.1.00℃. The probability of above predictions ranges from 0.64 to 0.73.

关键词： Qinghai-Xizang railway, annual mean air temperature, sunspot cycle length (SCL), atmospheric carbon dioxide concentration (CO2), prediction.

Relationships between δ ^(1.)O in summer precipitation and temperature and moisture trajectories at Muztagata, western china

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Science china Earth {1. 2006年第1期49卷 27-35页

作者： YU Wusheng1,2, YAO Tandong1,2, TIAN lide1,2, li Zhen2, SUN Weizhen2 & wang Yu2 1. Laboratory of Environment and Process on Tibetan Plateau, {3. of Tibetan Plateau research, chinese academy of sciences, Beijing 100085, china 2. Key Laboratory of Cryosphere and Environment, Jointly Established by cold and arid regions environmental and Engi-neering research {3. and {3. of Tibetan Plateau research, chinese academy of sciences and chinese academy of Meteorological sciences, china Meteorological Administration, CAS, lanzhou 73.000, china 1. Laboratory of Environment and Process on Tibetan Plateau Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China 2. Key Laboratory of Cryosphere and Environment Jointly Established by Cold and Arid Regions Environmental and Engineering Research Institute and Institute of Tibetan Plateau Research Chinese Academy of Sciences and Chinese Academy of Meteorological Sciences China Meteorological Administration Lanzhou 730000 China

Based on summer observations of stable isotope of precipitation at Muztagata, western china, during 2002―2003. this paper presents the relationship between δ 1.O in precipitation and air temperature, and discusses the effect of moisture transport on δ 1.O in precipitation. Results show that air temperature correlates positively with δ 1.O in precipitation, and the temperature effect controls the δ 1.O of precipitation in this area. The Muztagata region exhibits high δ 1.O values in summer precipi-tation, similar to those shown at stations in adjacent {1.. According to the results of our model set up to trace the moisture trajectories, the westerlies and local moisture circulation contribute to varia-tions of oxygen isotopes in precipitation. In addition, the impacts of the moisture transport distance, the moisture transport level, and the incursion of the polar air mass also influence the variations of δ 1.O in precipitation. The moisture origins and transport mechanisms also contribute to the variation of δ 1.O in precipitation at Muztagata.

关键词： Muztagata, δ1.O, precipitation, temperature, moisture transport.

Physico-chemical Characteristics and environmental Significance of Snow Deposition on Haxilegen Glacier No.51.in Tian Shan,{1.

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Journal of Mountain Science 2011年第3期8卷 484-494页

作者： DONG Zhiwen li Zhongqin ZHANG Mingjun {1. Feiteng WU lihua State Key Laboratory of Cryospheric sciences Cold and Arid Regions Environmental and Engineering Research Institute /Tianshan Glaeiological Station CAS Lanzhou 730000 China College of Geography and Environment Science Northwest Normal University Lanzhou 730070 China Graduate University of chinese academy of sciences Beijing 100049 China

Snow chemistry on the glaciers of alpine regions is a good indicator of atmospheric {1. *** examine snow chemistry in three snowpits at different altitudes on the Haxilegen Glacier No.51.in the Kuitun River source,Tian Shan,{3.,during July-September 2004 to *** use correlation analysis,factor analysis and sea-salt tracing methods to examine the characteristics and sources of major ions and mineral dust particles in the *** show that mineral dust particles and major ions in the snow pits vary *** the Asian dust period in springtime,the concentration of mineral dust particles and major ions deposited in snow is high,while the concentration is relatively low during the non-dust period of summer and *** may be caused by dust storm activity in central *** order of major ionic concentrations in the snow packs was determined to be Ca2+ > SO42-> NH4+ > NO3.> Cl-> Na+ > Mg2+ > K+.Ca2+ was the dominant cation;SO42- was the dominant *** find,with the exception of NO3.,that the variabilities of ionic concentrations are highly *** show that the glacier region was significantly affected by dust activity and anthropogenic *** major ions,especially Na+,originate from dust sources of central Asia and from the Ocean,transported by the westerly winds.

关键词： Snow chemistry Mineral dust environmental significance Haxilegen glacier No. 51 Tian Shan

Using lightning locating system based on time-of-arrival technique to study three-dimensional lightning discharge processes

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Science china Earth {1. 2010年第4期53卷 591-602页

作者： ZHANG GuangShu1,wang YanHui1,QIE XiuShu2,ZHANG Tong1,ZHAO YuXiang1,3.li YaJun1 & CAO DongJie11 Laboratory for Climate Environment and Disasters of Western{3.,cold and arid regions environmental and Engineering research institute,chinese academy of sciences,{13. 73.000,china 2 Laboratory for Middle Atmosphere and Global Environment Observation(LAGEO),institute of Atmospheric Physics,chinese academy of sciences,Beijing 100029,china 3.Department of Physics,Tianshui Normal College,Tianshui 741001,china 1. Laboratory for Climate Environment and Disasters of Western{1. Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China2. Laboratory for Middle Atmosphere and Global Environment Observation (LAGEO) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China3. Department of Physics Tianshui Normal College Tianshui 741001 China

A time-of-arrival(TOA) system based on GPS technology for locating VHF radiation sources from lightning has been developed and used in observation sites in the northern Shandong Province,*** 3. images of the lightning progression have been obtained successfully for the first time in *** 3.-channel evolutions of typical negative CG,positive CG and IC lightning flashes have been discussed together with the data of fast electric field *** was found that significant differences existed between the negative and positive CG lightning flashes in terms of the initiation and propagation of the radiation *** preliminary breakdown of a negative CG lightning flash propagated at a speed about 5.2×1.4 m/*** stepped leader of negative CG lightning flashes was trigged by negative initial ***,it propagated downward at a speed of 1.3.1.5 m/*** initial process of the positive CG lightning flashes was also a propagation process of negative *** streamers propagated dominantly horizontally in the positive charge region and accumulated positive charges at the origin of the lightning,and as a consequence,initiated downward positive streamers.A new type of lightning discharge that was triggered by a narrow bipolar pulse(NBP) is discussed in this *** NBP was originated at altitude of about 1..5 km in the upper positive charge *** a distinct difference from normal IC flash,its channels extended horizontally all around and produced a lot of radiation *** source power of the NBP could approach 1..7 kW,which is much greater than that of normal lightning discharge ranging between 1.0 mW and 500 *** 3. propagation of this new type of lightning discharge was observed and obtained for the first time in *** possible initiation mechanism of this new type of light-ning is discussed here.

关键词： time-of-arrival(TOA) technique three dimensional lightning locating system discharge process narrow bipolar pulse new-type of IC lightning

Snowpack variations and their hazardous effects under climate warming in the central Tianshan Mountains

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Advances in Climate Change {1. 2024年第3期15卷 442-451页

作者： jian-Sheng HAO Yan {1. Lan-Hai li Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences(CAS)Beijing 100101China Xinjiang Key Laboratory of Water Cycle and Uti{1.zation in arid Zone Urumqi 830011China State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Tianshan Snowcover and Avalanche Observation and research Station of Xin{1.g Xinyuan 835800China CAS research Center for Ecology and Environment of Central Asia Urumqi 830011China

Climate change alters snowpack evolution,which in turn influences the likelihood of snow avalanches and flood *** lack of systemic observational data on key snow characteristics in high mountains remains a scientific challenge in terms of systematically elucidating the dynamic chain of variations in climate-snowpack-snow *** restricts our understanding and poses challenges in the prediction of snow-related disaster *** such,this study analysed the variations of temperature and snowfall and the physical characteristics of snowpacks based on ground-based observations from the Kunse River Valley situated in the Tianshan Mountains from 1.67 to *** results reveal that the temperature increased significantly by 0.3.°C per decade(p1.during the snow season,along with more extreme snowfall *** snow-cover duration was observed to have been shortened by 4.77 d per decade(p1.from 1.67 to 2021.which is characterised by later snow-cover onset and earlier ***,average and maximum snow depths increased along with an increase in peak snow water equivalent,thus indicating a higher frequency of extremely scarce or abundant snow *** low snowpack temperature gradient and earlier snowmelt dates in spring lead to earlier occurrences of snowmelt floods and wet *** the risks of these events increase,they pose greater threats to farmlands,road transportation,water-electricity infrastructure and several other human ***,these insights are critical for providing vital information that can deepen our understanding of the impact of climate change on snowpack characteristics and improve management strategies for snow-related disaster prevention and mitigation.

关键词： Climate change Snowpack variations Snow-related disaster Tianshan Mountains

Bi_(2)S_(3. nanofiber bunch for highly efficient CO_(2) electroreduction to formate at low overpotential

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Rare Metals 2024年第7期43卷 3391-3399页

作者： li {1. Wen-Ke Gui Shan jiang liang {1. jian-Ping Yang State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China Centre for Catalysis and Clean Energy Griffith UniversityGold Coast CampusGold CoastQLD 4222Australia

Electrochemical conversion of CO_(2) into valuable chemicals represents a promising strategy to alleviate the environmental issues caused by excessive CO_(2) levels in the *** this work,Bi_(2)S_(3. with different morphologies have been fabricated via facile hydrothermal method to investigate the CO_(2) electrochemical reduction process.

关键词： process. facile Electrochemical