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Research in cold and arid {2. 2009年第3期1卷 238-248页

作者： Qi Feng 1,2. HaiYang Xi 1, Wei Liu 1,3. JianHua Si 1,2. ZongQiang Chang 1,2. YongHong Su 1,2.1. cold and arid {2. environmental and Engineering Research institute, chinese academy of sciences, lanzhou, Gansu 730000, china. 2. Alashan Desert Eco-hydrology Experimental Research Station, lanzhou, Gansu 730000, china. 3. {12. {13. laboratory of Hydrosciences and Engineering, Tsinghua University, Beijing 100084, china. chinese Acad Sci Cold & Arid Reg Environm & Engn Res Inst 320 West Donggang Rd Lanzhou 730000 Gansu Peoples R China Alashan Desert Ecohydrol Expt Res Stn Lanzhou 730000 Gansu Peoples R China Tsinghua Univ State Key Lab Hydrosci & Engn Beijing 100084 Peoples R China

Water is a primary controlling factor for economic development and ecological environmental protection in the inland river basins of arid western{2.. And it is groundwater, as the most important component of total water resources, that plays a dominant role in the development of western{2.. In recent years, the use-ratio of surface water has been raised, the groundwater recharge rate from surface water has been reduced, and groundwater has been exploited on a large scale. This has led to the decline of ground-water levels and the degradation of eco-environments in the Heihe watershed. Therefore, the study on the change in groundwater levels in recent years, as well as simulating and predicting groundwater levels in the future, have become very significant for im-proving the ecological environment of the Heihe River Basin, to coordinate the water contradiction among upper, middle and lower reaches of Heihe River Basin and to allocate the water resources. The purpose of this study is to analyze the groundwa-ter-level variations of the Ejina region based on a large scale, to develop and evaluate a conceptual groundwater model in Ejina Basin, to establish the groundwater flow model using the experimental observation data and combining Modular Three-Dimensional Groundwater Flow Model (MODFLOW) and GIS software, to simulate the regional hydrologic regime in re-cent 10 years and compare various water-delivery scenarios from midstream, and to determine which one would be the best plan for maintaining and recovering the groundwater levels and increasing the area of Ejina oasis. Finally this paper discusses the pos-sible vegetation changes of Ejina Basin in the future.

关键词： groundwater flow model Ejina Basin MODFLOW Heihe River

Effects of short-term low temperatures on photosystem Ⅱ function of samara and leaf of Siberian maple (Acer ginnala) and subsequent recovery

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Journal of arid Land 2009年第1期1卷 57-63页

作者： XiangLiang PAN1, DaoYong ZHANG1,2. Xi CHEN1, Li LI1, GuiJin MU1, LanHai LI1, AnMing BAO1, Jing LIU2. HuaiSong ZHU1, WenJuan SONG1, JianYing YANG1, JunYong AI1 1 Xinjiang institute of Ecology and Geography,{3., Urumqi 83.011,{2. 2.state key laboratory of environmental Geochemistry, institute of Geochemistry,{3., Guiyang 550000,{2. Xinjiang institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China state key {2. of {3. Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550000 China

Samara is the reproductive organ (seed) for many tree species in arid land in northwestern china. It is ecologically important in population development due to its dispersal function. However, information on its photosynthesis and effect of {2. stresses on its photosynthesis is still very limited. In the present study, responses of photosystem II (PSII) activity in samara and leaf of Siberian maple to short-term chilling/freezing and subsequent recovery potential were comparatively investigated by using polyphasic fluorescence test. The samara had more efficient photosynthesis (Fv/Fm and PIABS) and more efficient electron transport (φEo) but lower energy dis- sipation (DIo/RC) than leaf. Generally, the PSII performance and the electron transport for both samara and leaf were inhibited under low temperature stress, accompanied by an increase of energy dissipation in PSII reaction centers (RCs). PSII of both samara and leaf was not markedly affected by chilling and could acclimate to chilling stress. Short-term freezing could completely inhibit PSII activity in both samara and leaf, indicated by the drop of values of Fv/Fm, PIABS, φEo to zero. PSII functional parameters of short-term dark {3. samara could be largely recovered whereas those of {3. leaf could not be recovered. The higher tolerance of samara to short-term low temperature stress than leaf is of great ecological significance for seed development, population establishment of Siberian maple.

关键词： samara photosystem Ⅱ JIP-test analysis chlorophyll fluorescence

Distribution of δ18O in surface snow along a transect from Zhongshan Station to Dome A,East Antarctica

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Distribution of δ18O in surface snow along a transect from ...

Impact of human activities on soil respiration:A review

中国科学院地质与地球物理研究所第十届(2.10年度)学术年会

作者： DING MingHu~(1,2,3.),XIAO CunDe~2,JIN Bo~4,REN JiaWen~2,QIN DaHe~2 & SUN WeiZhen~2 1 Division of Cenozoic Geology and Environment,institute of Geology and Geophysics,chinese academy of {3.,Beijing 100029,china 2 state key laboratory of Cryospheric {3.,cold and arid regions environmental and Engineering Research institute,chinese academy of {3.,lanzhou 730000,china 3.Graduate University of chinese academy of sciences,Beijing 100049,china 4 chinese Arctic and Antarctic Administration,Beijing 100860,china

Surface snow samples were collected during the 14th(1997/1998)and 2.th(2.07/2.08){3. National Antarctica Research Expeditions along a transect from Zhongshan Station to Dome *** stable oxygen isotope ratios of these samples were measured to investigate their relationships with temperature and geographical parameters(latitude,longitude,altitude and distance to the coast).The results reveal a strong positive correlation(R=0.945)betweenδO and mean annual temperature,with a gradient of 0.84‰℃,which is a little higher than that in Terre Adelie *** analyses also show that theδO of surface snow is strongly correlated with distance to the coast(R=0.942.,latitude(R=0.942.,and altitude(R=0.941).But no significant correlation was found betweenδO and longitude in study *** should be the most important factor influencing theδO distribution because of distinctive ***δO-altitude and T-altitude gradients along this transect are determined to be-1.1‰/100 m and 1.3.℃/100 m,respectively.

关键词： Antarctica ITASE isotope Dome A δ18O chinaRE

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Research in cold and arid {2. 2009年第4期1卷 287-299页

作者： Fang Zhang,Tao Wang,Xian Xue,Jian Guo state key {2. of Desert and Desertification,{3. and arid regions environmental Engineering Research institute,Chi-nese academy of sciences,lanzhou,Gansu 730000,{12.. 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 {3. 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

降温速率和粒径对砂土中甲烷水合物形成过程影响研究

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天然气地球科学 2011年第5期22卷 920-925页

作者：蒋观利吴青柏展静中国科学院寒区旱区环境与工程研究所冻土工程国家重点实验室甘肃兰州730000

为研究降温速率和多孔介质粒径对天然气水合物形成过程的影响,在2.不同粒径的砂土中开展了甲烷水合物的形成实验研究。5个不同的降温速率被应用到2.粒径砂土中甲烷水合物的形成实验。实验结果表明,降温速率对砂土中甲烷水合物的成核... 详细信息

为研究降温速率和多孔介质粒径对天然气水合物形成过程的影响,在2.不同粒径的砂土中开展了甲烷水合物的形成实验研究。5个不同的降温速率被应用到2.粒径砂土中甲烷水合物的形成实验。实验结果表明,降温速率对砂土中甲烷水合物的成核时间有明显的影响。降温速率越快,甲烷水合物所需的成核时间就越短。同时,降温速率越慢,甲烷气体形成甲烷水合物的气体转化率就越高。不同的降温速率也影响形成实验中降温阶段和恒温阶段的甲烷水合物形成情况。在较低的降温速率下,恒温阶段的气体转化率相对较少。不同的多孔介质对甲烷水合物的形成过程也具有明显的影响。相对来说,在相同条件下,甲烷水合物在粗砂土中比在细砂土中更容易形成;在粗砂土中形成甲烷水合物,其气体转化率比在细砂土中形成的甲烷水合物更高。

关键词：甲烷水合物降温速率粒径砂土成核时间气体转化率

Thermal features of Qinghai-Tibet Railway Embankment with Crushed-stone Slope Protection in Permafrost regions

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地学前缘 2009年第S1期16卷 58-58页

作者： Guoyu Li,Ning Li,Wei Ma,Huijun Jin,Yu Sheng state key {2. of {3. soil Engineering,cold and arid regions environmental and Engineering Research institute, chinese academy of Science,{12. {{13.,china.

The Embankment with Crushed-Stone Slope Protection(ECSSP) in permafrost regions is an effective measure to cool subgrade and protect *** can mitigate the engineering hazards of the Qinghai-Tibet railway in the permafr... 详细信息

关键词： Qinghai-Tibet railway embankment with crushed-stone slope protection mechanisms of cooling effect thermal regime heat flow

Black Carbon Deposition and High Asia Glaciers

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Black Carbon Deposition and High Asia Glaciers

Modeling the Roles of Precipitation Increasing in Glacier Systems Responding to Climate Warming—Taking Xinjiang Glaciated Region as Example

强化科技基础推进气象现代化——第2.届中国气象学会年会

作者： Jing Ming1, 2. Cunde Xiao2. Zhencai Du3. Xingguo Yang2.1{3. National Climate Center (CNCC), Beijing 100081,{3. 2.{2. key laboratory of Cryospheric sciences (SKLCS), cold and arid regions {13. and Engineering Research institute, chinese academy of sciences,{12.,{3. 3.institute of Atmospheric Physics, chinese academy of sciences, Beijing 10002.,{3.

Black carbon (BC) is now concerned as one of the most significant factors impacting environment and climate mainly from anthropogenic activities. One aspect of its impacts is that the accelerated snow and ice in nature when BC is deposited in their surfaces. Since 2.00, 18 High Asia glaciers have been surveyed for black carbon deposition 2. times, and numerous snow samples and ice cores have been collected by researchers. However, most of the results were interpreted individually in papers. Here, we assemble the data and discuss the distribution of BC deposition and its impacts on the melting of the glaciers through radiative forcing. We find that BC distribution on the surfaces of High Asia glaciers primarily depends upon their elevations (i.e., higher sites have lower concentrations) and then on regional BC emissions associated with surface melting conditions. BC concentrations in High Asia glaciers are similar to the Arctic and western American mountains but are significantly less than heavy industrialized areas such as northern china. Although Himalayan glaciers, which are important due to their water resources, are directly facing the strong emissions from South Asia, their mean BC is the lowest due to high elevations. A new finding indicated by ice core records suggested great valleys in the eastern Himalayan section are effective pathways for BC entering the Tibetan Plateau and makes increasing BC trends in the local glaciers. On average, BC deposition causes a mean forcing of ～6 W m-2.(roughly estimated 5% of the total forcing) in High Asia glaciers and therefore may not be a major factor impacting the melting of most glaciers.

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Journal of Mountain Science 2005年第4期2卷 306-312页

作者： WANG Xin XIE Zichu LIU Shiyin TAO Jianjun HAN Yongshun YANG Yuelong Research institute of Geo-spatial Information Science Hunan University of Science ＆ Technology Xiangtan 411201 Hunan China key laboratory of Ice Core and {2. Region＇s Environment Cold and Arid Regions Environmental and Engineering Research Institute CAS Lanzhou 730000 China institute of Resources and Environment Hunan Normal University Changsha 410081 China institute of Tibetan Plateau Research CAS Beijing 100029 China

The studies on prediction of climate in Xinjiang almost show that the precipitation would increase in the coming 50 years, although there were surely some uncertainties in precipitation predictions. On the basis of the structure of glacier system and nature of equilibrium line altitude at steady state （ELAo）, a functional model of the glacier system responding to climate changes was established, and it simultaneously involved the rising of summer mean temperature and increasing of mean precipitation. The results from the functional model under the climatic scenarios with temperature increasing rates of 0.01, 0.03.and 0.05 K/year indicated that the precipitation increasing would play an evident role in glacier system responding to climate change： if temperature become 1 ℃ higher, the precipitation would be increased by 10%, which can slow down the glaciers retreating rate in the area by 4 %, accelerate runoff increasing rate by 8 % and depress the ELAo rising gradient by 2. m in northern Xinjiang glacier system where semi-continental glaciers dominate, while it has corresponding values of only 1%, 5 % and 18m respectively in southern Xinjiang glacier system, where extremely continental glaciers dominate.

关键词： Glacier system climate warming precipitation increasing role

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Editor’s note

chinese Science Bulletin 2009年第16期54卷 2723-2723页

作者： YAO TanDong & TIAN LiDe key laboratory of Tibetan Environment Changes and Land Surface Processes, {2. of Tibetan Plateau Research,{3., Beijing 100085, china state key laboratory of Cryosphere sciences, cold and arid regions Environment and Engineering Research {2.,{3., lanzhou 730000, china key laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China state key {2. of Cryosphere {3. Cold and Arid Regions Environment and Engineering Research Institute Chinese Academy of Sciences Lanzhou China

In 1961, the Global Network Isotopes in Precipitation (GNIP) was operated by the IAEA in collaboration with WMO, and over 500 stations across the globe participated in this program. The initial objective of this progr... 详细信息

关键词：环境同位素世界气象组织水文地球化学国际原子能机构大气环流模式气温变化水资源管理全球网络