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research in cold and arid regions 2009年第3期1卷 199-206页

作者： XinRong Li 1,2, ZhiShan Zhang 1,2, Lei Huang 1,2, LiChao Liu 1,2, XinPing Wang 1,2 1. Shapotou Desert research and Experiment Station, cold and arid regions environmental and engineering research institute, chinese academy of sciences, lanzhou, Gansu 730000, china. 2. Laboratory of Stress Ecophysiology and Biotechnology, cold and arid regions environmental and engineering research In-stitute, chinese academy of sciences, lanzhou, Gansu 730000, china. chinese Acad Sci Cold & Arid Reg Environm & Engn Res Inst Shapotou Desert Res & Expt Stn Lanzhou 730000 Gansu Peoples R China chinese Acad Sci Cold & Arid Reg Environm & Engn Res Inst Lab Stress Ecophysiol & Biotechnol Lanzhou 730000 Gansu Peoples R China

arid zones, which cover approximately 40 percent of the earth’s land surface, support complicated and widely varied ecological systems. As such, arid zones are an important composition of the global terrestrial ecosystem, and water is the key and abiotic lim-ited factor in ecosystem-driven processes in these areas. Ecohydrology is a new cross discipline that provides, in an objective and comprehensive manner, novel ideas and approaches to the evaluation of the interaction and feedback mechanisms involved in the soil–vegetation systems in arid zones. In addition, ecohydrology provides a theoretical basis of ecological restoration that is cen-tered on vegetation construction. In this paper, long-term monitoring and local observations in the transitional belt between a de-sertified steppe and a steppified desert at the Shapotou Desert research and Experiment Station, Tengger Desert, in northern china, were evaluated. The primary achievements and related research progress regarding ecohydrology in arid zones were analyzed and summarized, as a keystone, and the response of soil ecohydrological processes to the changes in the species composition, structure, and function of sandland vegetation was discussed. Meanwhile, the long-term ecological effects and mechanism of regulation of vegetation on soil habitat and on water-cycling were considered. As a vital participant in the ecohydrological processes of soil–vegetation systems, the studies on biological soil crusts was also summarized, and related theoretical models of restoration based on the water balance was reviewed.

关键词： vegetation regulation by soil moisture ecohydrology process biological soil crust ecological restoration of soil–vegetation systems

Meteorological Features at 6523 m of ***(Everest)between 1 May and 22 July 2005

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Journal of Mountain Science 2006年第3期3卷 181-190页

作者： XIE Aihong REN Jiawen QIN Xiang JIANG Youyan Joint Key Laboratory of Cryosphere and Environment Cold and Arid Regions Environment and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

Mt. Qomolangma （Everest）, the highest mountain peak in the world, has little been studied extensively from a meteorological perspective, mostly because of the remoteness of the region and the resultant lack of meteorological data. An automatic weather station （AWS）, the highest in the world, was set up on 27 April 2005 at the Ruopula Pass （6523 m asl） on the northern slope of Mt. Qomolangma by the team of integrated scientific expedition to Mt. Qomolangma. Here its meteorological characteristics were analyzed according to the lo-minute-averaged and 24-hour records of air temperature, relative humidity, air pressure and wind from 1 May to 22 July 2005. It is shown that at 6523 m of Mt. Qomolangma, these meteorological elements display very obvious diurnal variations, and the character of averaged diurnal variation is one-peak-and-one-vale for air temperature, one-vale for relative humidity, two-peak-and-two-vale for air pressure, and one-peak with day-night asymmetry for wind speed. In the 83 days, all the air temperature, relative humidity and air pressure increased with some different fluctuations, while wind speed decreased gradually and wind direction turned from north to south. The variations of relative humidity had great fluctuations and obvious local differences. Then the paper discusses the reason for the characters of diurnal and daily variations. Compared with the corresponding records in May 1960, 5-day-averaged maximums, minimums and diurnal variations of air temperature in May 2005 were apparently lower.

关键词： Mt. Qomolangma (Everest) radiation air temperature relative humidity pressure

Analysis of the effects of rising temperature for embankments under seismic loads in cold regions

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research in cold and arid regions 2009年第4期1卷 316-321页

作者： ZhiQiang Liu 1,2,Hao Lu 1 1.School of Civil engineering,lanzhou Jiaotong University,lanzhou,Gansu 730070,china.2.State Key Laboratory of Frozen Soil engineering,cold and arid regions environmental and engineering research institute,chinese academy of sciences,lanzhou,Gansu 730000,china. lanzhou Jiaotong Univ Sch Civil Engn Lanzhou 730070 Gansu Peoples R China chinese Acad Sci Cold & Arid Reg Environm & Engn Res Inst State Key Lab Frozen Soil Engn Lanzhou 730000 Gansu Peoples R China

The effect of temperature rising for frozen soil because of dynamic load was investigated by indoor *** and railway embankments are always loaded by dynamic loads such as earthquakes and *** the Qinghai-Tibetan Plateau is a re-gion where earthquakes occur frequently,it is essential to consider the temperature-rising effect of earthquakes or vehicles on railway and road *** this paper and according to the theories of heat transfer and dynamic equilibrium equations,as-suming frozen soil as thermal elastic-viscoplastic material,taking the combination of thermal and mechanical stresses into account,we present the numerical formulae of this dynamic problem,and the computer program of the two-dimensional finite element is *** the program,the dynamic response analyses for embankments loaded by earthquake are worked *** in-dicated that the temperature-rising effect result from earthquakes for embankment in nonuniform distribution in some small areas,the maximum rising temperature is 0.16 ?C for consideration in this paper.

关键词： Qinghai-Tibetan railway temperature-rising effect frozen soil embankment

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大规模引水隧洞群施工方案三维有限元分析

水力发电学报 2004年第6期23卷 83-87页

作者：张志强李宁徐彬西安理工大学岩土所西安710048

应用奥地利大型岩土工程数值仿真分析软件FINAL[1],对马来西亚BAKUN水电站8条引水隧洞的三种开挖顺序进行了模拟施工过程的三维有限元仿真分析。通过分析,评价了引水隧洞施工期围岩稳定性与支护结构安全性,评价了锚喷结构的支护效果,最... 详细信息

应用奥地利大型岩土工程数值仿真分析软件FINAL[1],对马来西亚BAKUN水电站8条引水隧洞的三种开挖顺序进行了模拟施工过程的三维有限元仿真分析。通过分析,评价了引水隧洞施工期围岩稳定性与支护结构安全性,评价了锚喷结构的支护效果,最终得到了三种方案中最优的开挖顺序,对于类似工程的设计具有指导与借鉴意义。

关键词：水工隧洞开挖顺序有限元分析围岩稳定性大规模

Effect of temperatures and moisture content on germination of Ammopiptanthus mongolica seeds

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Effect of temperatures and moisture content on germination o...

research ON AERODYNAMIC ROUGHNESS

中国植物学会七十五周年年会

作者： Yi Li (Dunhuang Gobi and Desert Ecology and Environment research Station,cold and arid Region environmental and engineering research institute,chinese academy of sciences,lanzhou,730000)

The seed experiment with Ammopiptanthus mongolica was started in 2006 at lanzhou,china. Seeds of 4.67% and 3.73% moisture content(MC)were kept at 45,25 and 15℃ in hermetically sealed *** initial germination was 96.7%...

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RESEARCH ON AERODYNAMIC ROUGHNESS

庆祝中国力学学会成立50周年暨中国力学学会学术大会’2007

作者： MU Qingsong~(*,+) MIAO Tiande~* DONG Zhibao~+ *(Department of Mechanics,School of Civil engineering and Mechanics,lanzhou University,lanzhou 730000,china) +(Key Laboratory of Desert & Desertification,cold and arid regions environmental and engineering research institute,chinese academy of sciences,lanzhou 730000,china)

Theoretical analysis and numerical simulation are used to explain important experimental *** examples,when the wind velocity above the boundary layer increases,the aerodynamic roughness length decreases nonlinearly wi... 详细信息

关键词： wind velocity roughness length shear velocity displacement height geometric shape of roughness elements Nikuradse’s hydro-dynamical theory of roughness

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金塔绿洲不同下垫面辐射特征对比分析

太阳能学报 2006年第7期27卷 713-718页

作者：陈世强文莉娟吕世华奥银焕张宇中科院寒区旱区环境与工程研究所兰州730000

利用2005年在甘肃省金塔绿洲开展的“绿洲系统能量与水分循环过程观测试验”所取得的资料，系统的分析了夏季晴天金塔地区不同下垫面的辐射收支特征，结果表明：地表反照率呈“U”型分布，戈壁的最大，日平均为0．23，依次为沙漠点0．2... 详细信息

利用2005年在甘肃省金塔绿洲开展的“绿洲系统能量与水分循环过程观测试验”所取得的资料，系统的分析了夏季晴天金塔地区不同下垫面的辐射收支特征，结果表明：地表反照率呈“U”型分布，戈壁的最大，日平均为0．23，依次为沙漠点0．2、绿洲点0．19、临近沙漠的绿洲点0．18。4个观测站的太阳总辐射基本相近，在观测期内未出现超太阳常数的现象。向下和反射的短波辐射具有相同的日变化规律。4站大气逆辐射全天约在300～400Wlrn2之间。绿洲的地面向上的长波辐射强度小，日变化也不明显，白天略大于夜间；戈壁和沙漠的向上长波辐射强度较大，日变化较明显，其峰值远大于绿洲和临近沙漠的绿洲上的。绿州地表放射的净长波辐射与短波吸收辐射之比分别为25％和33％，远小于沙漠和戈壁地区的比值57％、60％，仅为沙漠和戈壁地区的比值的50％左右。在辐射平衡中地表长波贡献最大，大气逆辐射次之，总辐射第三，净辐射第四，反射辐射最小。绿洲上的净辐射可达总辐射的一半以上，而戈壁和沙漠上则仅略大于30％。

关键词：辐射收支金塔绿洲沙漠戈壁

陆地生态系统碳源与碳汇及其影响机制研究进展

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生态学杂志 2005年第1期24卷 37-42页

作者：李玉强赵哈林陈银萍中国科学院寒区旱区环境与工程研究所兰州730000 兰州交通大学环境与市政工程学院兰州730070

全球碳循环研究中发现 ,目前已知碳源与碳汇不能达到平衡 ,存在一个很大的碳失汇。大气、海洋和陆地生态系统是人工源CO2 的 3个可能的容纳汇 ,其中陆地生态系统最复杂、最具不确定性 ,因此陆地生态系统碳源与碳汇研究是全球碳循环研究... 详细信息

全球碳循环研究中发现 ,目前已知碳源与碳汇不能达到平衡 ,存在一个很大的碳失汇。大气、海洋和陆地生态系统是人工源CO2 的 3个可能的容纳汇 ,其中陆地生态系统最复杂、最具不确定性 ,因此陆地生态系统碳源与碳汇研究是全球碳循环研究的核心问题之一。大气成分监测、CO2 通量测定、森林资源清查以及模型模拟等方面的研究都表明 ,CO2 施肥效应、氮沉降增加、污染、全球气候变化以及土地利用变化 ,是影响陆地生态系统碳储量的主要生态机制 ,但不确定在过去的 10～ 10 0年以及未来哪一种机制起最主要的作用。

关键词：陆地生态系统碳源碳汇影响机制

Impact of human activities on soil respiration:A review

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research in cold and arid regions 2009年第4期1卷 287-299页

作者： Fang Zhang,Tao Wang,Xian Xue,Jian Guo State Key Laboratory of Desert and Desertification,cold and arid regions environmental engineering research institute,Chi-nese academy of sciences,lanzhou,Gansu 730000,china. chinese Acad Sci Cold & Arid Reg Environm Engn Res Inst State Key Lab Desert & Desertificat Lanzhou 730000 Gansu Peoples R China

Soil respiration is one of the primary fluxes of carbon between soils and the *** is produced by rhizosphere respiration and soil microbial *** respiration is not only affected by environmental factors,but also changes with the hu-man-induced disturbances of ***-use,the measures of land management,the pollution of soil,and so on can affect soil respiration and change the soil *** to some research,the authors summed up their impacts on soil respiration by human activities through land-use changes and land-management measures among agroecosystem,grassland ecosystem,and for-est *** results showed that (1) when adding fertilization to farmland,the soil respiration will increase;(2) fenced land can decrease soil respiration,while soil respiration in the grazed land at a grassland ecosystem will decline with the increasing of grazing intensity;(3) with grassland fertilization;farmland cultivation;fire,fertilization,and cutting of forest,conflicting results were found in the changes of soil *** plant species,site condition,and measurement season can lead to different results on soil respiration.

关键词： human activities soil respiration agroecosystem grassland ecosystem forest ecosystem