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Ice Surface-Elevation Change and Velocity of Qingbingtan Glacier No.72.in the Tomor Region,Tianshan Mountains,Central Asia

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Journal of Mountain Science 2011年第6期8卷 855-864页

作者： WANG Puyu LI Zhongqin LI Huilin WANG Wenbin WANG Feiteng College of Geography and Environment Science Northwest Normal University Lanzhou 730070 China State Key Laboratory of Cryospheric sciences Cold and Arid Region Environment and Engineering Research Institute/Tianshan Glaciological Station Chinese Academy of Sciences Lanzhou 730000 China

Glaciers in the Tomor region of Tianshan Mountains preserve vital water resources. However, these glaciers suffer from strong mass losses in the recent years because of global warming. From 2.08 to 2.09, a large-scale scientific expedition has been carried out in this region. As an individual reference glacier, the tongue area of Qingbingtan glacier No. 72.was measured by the high precise Real Time Kinematic-Global Position System （RTK-GPS）. In this paper, changes of the tongue area of Qingbingtan glacier No.72.has been studied based on topographic map, remote sensing image and the survey during 2.08-2.09 field campaign. Results indicated that the ice surface-elevation of the tongue area changed - 0.2.~0.14 m a-1 from 1964 to 2.08. The estimated loss in ice volume was 0.0144-0.009 km3, which represented a ~2. % decrease from the 1964 volume and was equivalent to average annual mass balance of -0.2.4-0.12.m water equivalent for the tongue area during 1964-2.o8. Terminus retreated by 1852.m, approximately 41 m a-1, with the area reduction of 1.533 km2.（0.034 km2.a-0 from 1964 to 2.09. Furthermore, the annual velocity reached to -70 m a-1. Comparing with the other monitored glaciers in the eastern Tianshan Mountains, Qingbingtan glacier No.72.experienced more intensive in shrinkage, which resulted from the combined effects of climate change and glacier dynamic, providing evidence of the response to climatic warming.

关键词： Ice surface-elevation change Ice velocity Qingbingtan glacier No70 Tomor region TianshanMountains

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Hydrological Characteristics of the Rongbuk Glacier Catchment in *** Region in the Central Himalayas,china

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Journal of Mountain Science 2010年第2期7卷 146-156页

作者： LIU Weigang REN Jiawen QIN Xiang LIU Jingshi LIU Qiang CUI Xiaoqing WANG Yetang State Key Laboratory of Cryospheric sciences Cold andArid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China institute of Tibetan Plateau research Chinese Academy of Sciences Beijing 10085 China

From 8 April to 11 October in 2.05, hydrological observation of the Rongbuk Glacier catchment was carried out in the Mr. Qomolangma （Everest） region in the central Himalayas, china. The results demonstrated that due to its large area with glacier lakes at the tongue of the Rongbuk Glacier, a large amount of stream flow was found at night, which indicates the strong storage characteristic of the Rongbuk Glacier catchment. There was a time lag ranging from 8 to 14 hours between daily discharge peaks and maximum melting （maximum temperature）. As melting went on the time lag got shorter. A high correlation was found between the hydrological process and daily temperature during the ablation period. The runoff from April to October was about 80% of the total in the observation period. Compared with the discharge data in 1959, the runoff in 2.05 was much more, and the runoff in June, July and August increased by 69%, 35% and 14%, respectively. The rising of temperature is a major factor causing the increase in runoff. The discharges from precipitation and snow and ice melting are separated. The discharge induced by precipitation accounts for about 2.% of the total runoff, while snow and ice melting for about 80%.

关键词： Central Himalayas Mt. Qomolangma Rongbuk Glacier Hydrological characteristics

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THE SAND WEDGE AND MIRABILITE OFTHE LAST ICE AGE AND THEIR PALEOCLIMATICSIGNIFICANCE IN HEXI CORRIDOR

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chinese Geographical Science 2001年第1期11卷 80-86页

作者： HU Gang, WANG Nai-ang (School of Resources and Environment, lanzhou University, lanzhou 730000, P. R. {2. cold and arid Regrons Environment and engineering research institute, the chinese Academy of Scienes, lanzhou 730000, P. R. {2.) School of Resources and Environment Lanzhou University Lanzhou P. R. China cold and arid Regrons Environment and {2. research institute the Chinese Academy of Sciences Lanzhou P. R. China

The sand wedges in Hexi Corridor occur in the alluvial gravel stratum of bajada and high terraces. The 14C ages of eolian sand in sand wedges prove that they formed during the Last Ice Age, with the mean annual air temperature about ? 5.6°C. The common 14C and AMS 14C dating ages of terrestrial branch relicts in Huahai clay-mirabilite interlayer are (11 600 ± 2.0) a B. P. and (1118 ± 54) a B. P. respectively, proving that the mirabilite formed at the cold episode of the Last Glacial Maximum(LGM) and Younger Dryers(YD) in Huahai Lake. It is pointed out that the mean annual air temperature in Hexi Corridor during LGM was about ?3°C – ?7°C, 11°C – 15°C lower than that of present, and that during YD was about 0°C – 2.C, 6°C – 8°C lower than at present. This decreasing temperature values are generally coincident with those inferred by pollen, sand wedge and ice core in the northern china, and also with the {2. on temperature-falling amplitude of middle and high latitude on the Northern Hemisphere recently.

关键词： sand wedge Last Ice Age Hexi Corridor paleoclimate

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

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Science china Earth sciences 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 china,cold and {2. regions environmental and engineering research institute,chinese Academy of sciences,lanzhou 730000,china 2.Laboratory for Middle Atmosphere and Global Environment Observation(LAGEO),institute of Atmospheric Physics,chinese Academy of sciences,Beijing 10002.,china 3 Department of Physics,Tianshui Normal College,Tianshui 741001,china 1. Laboratory for Climate Environment and Disasters of Western china 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,*** 3D images of the lightning progression have been obtained successfully for the first time in *** 3D-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 5.2.104 m/*** stepped leader of negative CG lightning flashes was trigged by negative initial ***,it propagated downward at a speed of 1.3×105 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 10.5 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 16.7 kW,which is much greater than that of normal lightning discharge ranging between 100 mW and 500 *** 3D 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

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The Glacier Area Changes in the Qangtang Plateau Based on the Multi-temporal Grid Method and its Sensitivity to Climate Change

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Journal of Mountain Science 2011年第6期8卷 882-893页

作者： WANG Liping XIE Zichu WANG Xin LIU Shiyin DING Liangfu SHANGGUAN Donghui The College of Resources and environmental Science Hunan Normal University Changsha China cold and arid {2. environmental and engineering research institute Chinese Academy of Sciences Lanzhou China Department of Geography Hunan University of Science and Technology Xiangtan China

Glacier area changes in the Qangtang Plateau are analyzed during 1970-2.00 using air photos,relevant photogrammetric maps and satellite images based on the multi-temporal grid *** results indicate that the melting of glaciers accelerated,only a few of glaciers in an advancing state during 1970-2.00 in the whole Qangtang ***,the glaciers seemed still more stable in the study area than in most areas of western *** estimate that glacier retreat was likely due to air temperature warming during 1970-2.00 in the Qangtang ***,the functional model of glacier system is applied to study climate sensitivity of glacier area changes,which indicates that glacier lifespan mainly depends on the heating rate,secondly the precipitation,and precipitation increasing can slow down glacier retreat and make glacier lifespan prolonged.

关键词： The Qangtang Plateau Glacier change Multi-temporal Climate change Functional model ofglacier system Simulation

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

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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 WANG 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 environmental *** examine snow chemistry in three snowpits at different altitudes on the Haxilegen Glacier No.51,in the Kuitun River source,Tian Shan,{2.,during July-September 2.04 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

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Simulation of oasis breeze circulation in the arid region of the Northwestern china

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Science china Earth sciences 2004年第z1期47卷 101-107页

作者： LU Shihua, AN Xingqin & CHEN Yuchuncold and arid {2. environmental and engineering research institute, chinese Academy of sciences, lanzhou 730000, china 1. cold and arid {2. environmental and engineering research institute Chinese Academy of Sciences 730000 Lanzhou China

In this paper, the process of oasis-desert circulation (ODC) is simulated by MM5V3.5 model through designing an ideal oasis-desert scheme and assuming that initial atmosphere is at rest (V= 0). The findings showed that the key of forming special oasis boundary structure is the difference of energy and water between oasis and desert. The evaporation of oasis surface consumes heat energy, and the low temperature of oasis causes an oasis breeze circulation (OBC), which drives an ODC with a downdraft over the oasis and an updraft over the desert. Later, the cold, dry and stable boundary over oasis is gradually formed, on the contrary, the atmospheric boundary over desert on the edge of oasis is hot, humid and unstable and its height is about 600 hPa. The updraft over the desert forms a wet ring that acts as a vertical wall weakening the low-level moisture exchange between the oasis and desert. The downdraft of OBC increases the atmospheric stability that reduces the oasis evaporation. The low-level outflow from the oasis (into the desert) prevents the dry, hot air flowing from the desert into the oasis. Thus an oasis self-preservation mechanism may be formed due to OBC. The horizontal area influenced by oasis is twice as oasis area and the vertical range is four times as oasis. The ODC is strong in the daytime and reaches the strongest at 17:00, and the influenced area is the largest at 2.:00.

关键词： oasis atmospheric boundary layer numerical simulation.

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Protective mechanism of desiccation tolerance in Reaumuria soongorica: Leaf abscission and sucrose accumulation in the stem

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Science china(Life sciences) 2007年第1期50卷 15-21页

作者： LIU YuBing1,2. ZHANG TengGuo1, LI XingRong2.& WANG Gang1 1 School of Life sciences, lanzhou University, {2., china 2.cold and arid regions environmental and engineering research institute, chinese Academy of sciences, {2., china 1. School of Life sciences Lanzhou University Lanzhou 730000 China 2. cold and arid {2. environmental and engineering research institute Chinese Academy of Sciences Lanzhou 730000 China

Reaumuria soongorica (Pall.) Maxim., a perennial semi-shrub, is widely found in semi-arid areas in northwestern china and can survive severe desiccation of its vegetative organs. In order to study the protective mechanism of desiccation tolerance in R. soongorica, diurnal patterns of net photosynthetic rate (Pn), water use efficiency (WUE) and chlorophyll fluorescence parameters of Photosystem II (PSII), and sugar content in the source leaf and stem were investigated in 6-year-old plants during progressive soil drought imposed by the cessation of watering. The results showed that R. soongorica was char-acterized by very low leaf water potential, high WUE, photosynthesis and high accumulation of sucrose in the stem and leaf abscission under desiccation. The maximum Pn increased at first and then de-clined during drought, but intrinsic WUE increased remarkably in the morning with increasing drought stress. The maximal photochemical efficiency of PSII (Fv/Fm) and the quantum efficiency of noncyclic electric transport of PSII(ΦPSII) decreased significantly under water stress and exhibited an obvious phenomenon of photoinhibition at noon. Drought stressed plants maintained a higher capacity of dis-sipation of the excitation energy (measured as NPQ) with the increasing intensity of stress. Conditions of progressive drought promoted sucrose and starch accumulation in the stems but not in the leaves. However, when leaf water potential was less than –2..3 MPa, the plant leaves died and then abscised. But the stem photosynthesis remained and, afterward the plants entered the dormant state. Upon re-watering, the shoots reactivated and the plants developed new leaves. Therefore, R. soongorica has the ability to reduce water loss through leaf abscission and maintain the vigor of the stem cells to survive desiccation.

关键词： Reaumuria soongorica desiccation photosynthesis sucrose water use efficiency leaf abscission

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The ecohydrology of the soil-vegetation system restoration in arid zones: a review

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research in cold and {2. 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 {2. regions environmental and engineering research institute, chinese Academy of sciences, lanzhou, Gansu 730000, {12.. 2. Laboratory of Stress Ecophysiology and Biotechnology, cold and {2. regions environmental and engineering research In-stitute, chinese Academy of sciences, lanzhou, Gansu 730000, {12.. 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

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Carbon assimilation characteristics of plants in oasis-desert ecotone and their response to CO2.enrichment

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Science china Earth sciences 2004年第S1期 39-49页

作者： SU Peixi, CHEN Huaishun, AN Lizhe & LIU Xinmincold and arid {2. environmental and engineering research institute, chinese Academy of sciences, lanzhou 730000, china

Six species of more than 2.-year-old desert woody plants in the oasis-desert ecotone were selected for study. The results showed that: (1) in different growing seasons δ13C values of assimilating organ varied between -14‰ and -16‰ for Haloxylon ammodendron (HA),-14‰-15‰ for Calligonum mongolicum (CM) and-2.‰- -2.‰ for Caragana korshinskii(CK), Nitraria sphaerocarpa (NS) and Hedysarum scoparium (HS). (2. The net photosynthetic rate (Pn) of HA and CM was significantly higher than those of the other species. With the decrease in Pn for the six species, their intercellular CO2.concentration increased, but stomatal limitation value decreased under the intensive light. At the same time, the photochemical efficiency of PS II dropped to different degrees. (3) The CO2.enrichment experiment demonstrated that, Pn of HA and CM increased to different extent under 450 umol/mol, but their Pn reduced or approximated to the current condition under 650 umol/mol. Under 450 umol/mol the efficiency for solar energy u

关键词： oasis-desert ecotone carbon assimilation stable carbon isotope ratio photoinhibition CO2.enrichment.

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