25 December 2003, Volume 25 Issue 6
    

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  • CHENG Guo-dong, JIANG Hao, WANG Ke-li, WU Qing-bai
    JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY. 2003, 25(6): 603-607. https://doi.org/10.7522/j.issn.1000-0240.2003.0106
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    Because thermodynamic characteristics are changeable on the interface between atmosphere and ground and then influence thermodynamic stability of permafrost under the interface while a highway or railway built above tundra, embankment of a certain height is used as a usual measure to keep the permafrost stable. After the embankment built, the heating effect that changes with direction of side slopes is a question, which must be taken into account in the engineering measure to keep the embankment frozen. In this paper, based on mathematical physical analyses and numerical simulation, methods for calculating the freezing index and thawing index of embankment surface and some thermodynamic parameters from the maximum and minimum monthly mean air temperature are developed and applied in the Beiluhe passage of the Qinghai-Tibet Railway in 2002 as an example. The quantitative analysis shows that to protect the permafrost along the Qinghai-Tibet railway is necessary and scientific. A case analysis shows that the permafrost in the Beiluhe region is in a critical status, even if no railway built. Slope exposure can cause strong asymmetric temperature distribution. The maximum difference of thermal status is between the south or near south direction and the north or near north direction of the embankment slopes, so it is necessary to take different measures for the two opposite embankment slopes, in order to mitigate the direct negative effect of locally taking soil to build embankment on the underlaying permafrost, to minish the asymmetric temperature distribution on the embankment surface and to avoid lengthways fissure taking place.
  • HE Ping, CHENG Guo-dong, YANG Cheng-song, ZHAO Shu-ping, ZHU Yuan-lin
    JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY. 2003, 25(6): 608-613. https://doi.org/10.7522/j.issn.1000-0240.2003.0107
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    Thawing-settlement coefficient is an important parameter for engineering design to estimate the thawing strain of frozen soils, which is related with soil type, water content and dry density. The coefficient increases with water content. In unsaturated state, the greater the dry density is, the larger the thawing-settlement coefficient is. But in saturated state, it decreases with increasing dry density. Based on the analyses of experiment results, the porosity in liquid limit state is suggested as a limit porosity to divide the water contribution degree for settlement deformation during freezing. When the porosity of frozen soil is greater than the limit porosity and the water fully fills the pore of soil, the water in excess of water content at liquid limit, as free water flowing out during thawing, should be counted completely as settlement deformation. So in the calculation of thawing settlement coefficient, the three states should be considered distinctively: non-saturation, saturation and super-saturation in which the water content is more than liquid limit. Contact ratio is suggested to estimate the contribution of unsaturated water content to settlement, which is zero when the water content is zero and 1 when the water content is up to saturated water content. In this paper the calculated method of thawing-settlement coefficient is presented and it has good prediction result as compared with measurement.
  • NIU Fu-jun, YU Qi-hao, LAI Yuan-ming
    JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY. 2003, 25(6): 614-620. https://doi.org/10.7522/j.issn.1000-0240.2003.0108
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    Ground temperature was monitored for two years in the Beiluhe Testing Section of the Qinghai-Tibet Railway, where a field-testing embankment was constructed and observed. Based on the monitoring, the ground temperature change, thermal regime and thermal process are discussed. It is found that the ground temperature change and thermal process of duct-ventilation embankment with ducts posited at half height of the embankment are similar to those of normal embankment. The temperature of the roadbed roundly increases during the first two freezing-thawing circles after the embankment complicated. Both of the normal embankment and the high-posited duct ventilation embankment are passive in protecting permafrost. However, the duct-ventilated embankment with deep-posited ducts shows a striking difference. The ground temperature of the roadbed soon decreases during the second freezing-thawing circle, though it increases during the first circle. The underlying permafrost begins emission after the first circle. Such process indicates that the ventilating ducts are active in cooling the underlying permafrost when they are laid deeply in the embankment.
  • ZHANG Xue-fu, SU Xin-min, LAI Yuan-ming, YU Wen-bing, WU Ya-ping
    JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY. 2003, 25(6): 621-627. https://doi.org/10.7522/j.issn.1000-0240.2003.0109
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    From in-situ measurement of air temperature and ground temperature inside the Kunlunshan Tunnel in the Qinghai-Tibet Railway, it is found that the thawed range of the permafrost surrounding the tunnel is very large, due to the hydration heat of the concrete lining, insulation measures during winter and other artificial activities. In this paper, taking water transfer and phase change into account, the finite element formulae of this problem and computer program on the base of ANSYS Software are derived from the governing differential equations and water transfer equations using Galerkin’s method. Using the computer program, forecast analysis for the re-freezing of the Kunlunshan Tunnel is made. The analysis shows that insulation will delay the re-freezing. The thawed range of the permafrost surrounding the tunnel in cold regions caused by tunneling must be considered. The observation duration should be prolonged, because much time is needed for the tunnel going to be stable.
  • ZHANG Jian-ming, SHENG Yu, LAI Yuan-ming
    JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY. 2003, 25(6): 628-631. https://doi.org/10.7522/j.issn.1000-0240.2003.0110
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    In this paper, the thermal conductivity of railway ballast is measured by steady comparison method. The experiment was carried out at room temperature and two thermal conditions, heated from below and from above, were studied. The test results show that the thermal conductivity of the railway ballast is almost the same for the two thermal conditions when the temperature difference between the top and bottom of the ballast is smaller. When the temperature difference of the ballast is larger, however, the thermal conductivity for the condition of being heated from below is greater than that of being heated from above. Moreover, under the condition of being heated from below, the thermal conductivity increases with increasing temperature difference between the top and bottom of the ballast. It means that the heat transfer in the railway ballast is dissymmetric for the two thermal conditions. For the engineering of railway construction in cold regions, it is hoped that the permafrost under the railway embankment can be protected and reinforced if this advantage of heat transfer in railway ballast is taken.
  • FENG Wen-jie, MA Wei, ZHANG Lu-xin, ZHOU Cheng-lin, WU Zhi-jian
    JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY. 2003, 25(6): 632-637. https://doi.org/10.7522/j.issn.1000-0240.2003.0111
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    From a laboratory-modeling test, combined with the air temperature and permafrost temperature data of a field test roadbed in Fenghuoshan, the advantage of riprap slope protection for rising permafrost table along a road or a railway in permafrost regions is shown. The superiority and feasibility of the riprap lope protection were confirmed. From the test results, it is found that riprap has an obvious function on permafrost table, and the change of permafrost table is positively related to air temperature. With climate warming, permafrost table will descend step by step, but at the same temperature, to add riprap can obviously uplift permafrost table. Thus, it is suggested to use riprap slope protection in the base of a slope. The riprap slope protection is a measure of actively controlling ground temperature, adjusting heat convection and controlling heat conduction. Riprap acts as a thermo-diode, transferring heat in one-way, largely lifting permafrost table. Riprap slope protection is very important for a roadway to operate in safety without block.
  • YU Wen-bing, LAI Yuan-ming, ZHANG Xu-fu, XIAO Jian-zhang, NIU Fu-jun, ZHANG Shu-juan
    JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY. 2003, 25(6): 638-643. https://doi.org/10.7522/j.issn.1000-0240.2003.0112
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    Engineering troubles of railway/roadway in cold regions are mainly caused by thaw settlement of permafrost. Reducing the embankment soil temperature and maintaining permafrost is the main construction principle. Experimental models of block stone layer and crushed stone layer were set in a big modeling chamber at one time. Temperature boundary of them was vibrated periodically with constant wind speed. The experiment shows that both the block stone and the crushed stone can cool the bottom of themselves. The cooling effect of crushed stone with a mean grain size of 7 cm is better than that of block stone whose mean grain size is about 22 cm, and the temperature at the bottom of crushed stone layer at the end of the test was 3.5 ℃ lower than that of block stone layer; At the end of the negative temperature period and the positive temperature period, temperature in block stone changes monotonously from top to bottom, but it is no-monotonously in crushed stone; At the end of positive temperature, temperature of block stone layer surface is warmer than the pore-air temperature in block stone layer; A critical thickness of block stone or crushed stone is the necessary condition if they have effects of cooling. The cooling function of block stone or crushed stone can be used to prevent asymmetry thaw settlement and longitudinal cracks of embankments and maintain the stability of slopes in permafrost regions.
  • DENG You-sheng, MA Wei, HE Ping, ZHOU Cheng-lin
    JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY. 2003, 25(6): 644-647. https://doi.org/10.7522/j.issn.1000-0240.2003.0113
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    The authors invent a macromolecule organic material as an additive. It mixes with soil in optimum moisture content and then compacted, desiccated and concreted. The material not only increase the groundwork soil strength, but also make the soil have many favorable features, such as low penetrability and low absorbability etc. Application of this material in pavement engineering is very favorable for environment conservation and cost reducing. So the macromolecule material is looked as a new kind of pavement materials. In laboratory, soil mixed with the additive is tested to verify the property of frost heave. The test results show: 1) When the test finished, there was no or less frost heaving (less than 1%) in the sample, no matter in a close system or in an open system; 2) When samples are tested in an open system that the sample is supplied with water during experimental processing, no water enters into the sample; 3) When the test finished, moisture content of frozen soil and unfrozen soil do not change clearly. The reason is that in the freezing process, the additive mixed with soil will change from liquid to colloid in the soil pore along with temperature decreasing. The change prevents the soil from frost heaving, water penetration, but also interdicts from the contact of soil pore, reducing water migration in pore. Thus frost heaving is prevented. This material used for preventing frost heaving in cold region engineering will have the significance of further popularizing and using.
  • WU Zhi-jian, MA Wei, WANG Lan-min, CHENG Jian-jun, FENG Wen-jie
    JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY. 2003, 25(6): 648-652. https://doi.org/10.7522/j.issn.1000-0240.2003.0114
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    On the low-temperature triaxial test apparatus of MTS-810 at State Key Laboratory of Frozen Soil Engineering, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, systematic dynamic characteristics of frozen soil under seismic dynamic loading were studied by means of dynamic triaxial tests. Dynamic shear strength tests of frozen soil under different temperatures (-2,-5 and-7 ℃) and different confining pressures (1, 3 and 5 MPa ) have been carried out, and the variations of parameters (dynamic cohesion (Cd) and dynamic friction angle (φd)) of these mechanical properties under different temperatures have also been studied systematically. It is found that the dynamic shear strength of frozen loess increases with increasing confining pressure, decreasing temperature and vibration number (N); Cd rises with falling N and temperature; φd ascends with rising N and descending temperature. Models for the influence of temperature and confining pressure on the dynamic strength were established.
  • WANG Gen-xu, SHEN Yong-ping, QIAN Ju, WANG Jun-de
    JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY. 2003, 25(6): 653-659. https://doi.org/10.7522/j.issn.1000-0240.2003.0115
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    The influence of vegetation change on the water balance in a drainage area is one of the pivotal problems in the study of hydrology and eco-hydrology. In this paper, two typical small drainage areas in the source regions of the Yellow River were taken as examples. For the alpine meadow widely distributed in the river source regions in the Tibetan Plateau, measuring the soil moisture content, infiltration process and evapotranspiration characteristics under different vegetation types and coverage conditions in the drainage areas shows that there was a significant correlation between the vegetation coverage and the soil moisture. Especially, the increasing of soil moisture with vegetation coverage could be described as a quadratic parabolic equation within the depth of 20 cm. When the original plant community is kept and coverage is higher, the water retention ability would be higher in the upper layers of soil. Meanwhile, the rate of water infiltrating from the surface to deeper and surface evapotranspiration would be lower, so the function of water conservation would be obvious. After the alpine meadow degrading, the meadow is getting dry, water retention ability reduces and surface evaporation becomes higher. Even if the meadow is amended artificially, soil moisture content and water retention ability cannot be improved obviously, and surface evapotranspiration would increase. It is very important to protect the original alpine meadow for the hydrological process in the river source regions.
  • ZHOU Shang-zhe, LI Ji-jun
    JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY. 2003, 25(6): 660-666. https://doi.org/10.7522/j.issn.1000-0240.2003.0116
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    There are broad planation surfaces, basins, and mountain ranges in the Tibetan Plateau. Research in the past several decades demonstrates that Quaternary glaciations developed around high mountains on the plateau only, not the whole plateau. In recent years, the oldest moraines in several mountain ranges are dated by ESR. The relative ages of these moraines were first confirmed based on their geomorphologic position and degree of weathering. It is revealed that the oldest glaciation, Zhonglianggan Glaciation, in the Qilian Mountains occurred at about 462.9 ka BP, and the high-elevation moraine of the Wangfeng Glaciation, the oldest one in the Tianshan Mountains, was dated at 477.1 and 459.7 ka BP. The oldest glaciation in the Hengduan mountains, Daocheng Glaciation, was dated at 571.2 ka BP, which is characterized by moraines with deeply weathered red soils with a SiO2/Al2O3 ratio of about 2.42 and a SiO2/R2O336Cl age of the bottom ice of a 309-m ice core from the Guliya Ice Cap. The Liuhuangshan Glaciation, the oldest one in the Nyainq阯gtanglha Rang, was dated at 678 ka BP. These dating results of the oldest moraines in several mountain ranges suggest that glaciers began to develop during MIS12 in the Qilian Mountains and Tianshan Mountains, MIS14 in the Hengduan Mountains and, perhaps, MIS16 in the Kunlun Mountains and Nyainqêngtanglha Rang. Cui Zhijiu and Li Jijun suggest that there was a widespread and rapid uplift of the plateau (Kunlun-Huanghe Tectonic Movement) from 1.1 to 0.6 Ma BP. It is believed that uplift of mountain ranges on the plateau during this period initiated a widespread mountain glaciation.
  • PENG Xuan-ming, WU Qing-bai, TIAN Ming-zhong
    JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY. 2003, 25(6): 667-671. https://doi.org/10.7522/j.issn.1000-0240.2003.0117
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    Owing to climate change and human activities, regional groundwater table and ecological water table are generally decreasing, resulting in a series of environmental geological problems, such as degradation of swampy meadow and vegetation, and desertification. On the base of field survey, the cause of the groundwater table decreasing is analyzed, and the relationship between the ecological environmental effect and groundwater table lowering is discussed. It is found that groundwater table has greatly changed. The groundwater outcrop in mountain areas are moving downwards with decreasing runoff. The groundwater table of civil well in river valleys has fallen 0.52 to 1.18 m. Meanwhile, lake shrinking causes groundwater table lowering around the basin and the outcome in alluvial and diluvium deposits also moves downwards. The groundwater table lowering is caused by permafrost degradation, geological structure action, lake shrinking and human activities. The survey results show that permafrost is in degradation in the headwaters of the Yellow River, discontinuous permafrost degrades into thawed area, the lower boundary of permafrost is rising, and permafrost table is decreasing. The permafrost degradation results in cryogenic waterproof layer moving downward and groundwater table obviously lowering. With groundwater table lowering, a series of ecological environmental problems appear. Swampy meadow and vegetation is in degradation and biological diversity is on the decrease owing to the ecological water table lowering and the depth of seasonal thaw layer increasing. Desertification is enlarging.
  • MA Xiao-bo, SHI Ya-feng, SHEN Yong-ping, YANG Bao
    JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY. 2003, 25(6): 672-675. https://doi.org/10.7522/j.issn.1000-0240.2003.0118
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    In this paper, instrumental meteorology station data in Northwest China and climatic proxy data such as tree-ring index, dryness and wetness grades series and solar activity index are used to analyze climate characteristics and changing trend. The results show that precipitation increases in west part of Northwest China significantly; solar activity is intensive in hundred-year scale, and tree-ring index indicates that dryness and wetness variation in Northwest China has a period of 64 years and has good positive relationship with sunspot’s 11-year cycle.
  • WU Guang-jian, YAO Tan-dong, XU Bai-qing, LI Zhen, BAO Han-zhang
    JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY. 2003, 25(6): 676-679. https://doi.org/10.7522/j.issn.1000-0240.2003.0119
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    In August 2002, temperatures of two ice-core boreholes (one borehole reached to the bedrock) at the altitudes of 6350 m (Core 2) and 6250 m (Core 3) a.s.l. in the Muztag Ata were measured by using a thermistor. It is found that the ice temperature in the Muztag Ata is the lowest among all the mountain ice cores in the middle-low latitudes. The measured minimum temperature is-21.79 ℃ at the depth of 35 m for Core 2, and-20.91 ℃ at the depth of 55 m for Core 3. The bedrock temperature is about-20.76 ℃ at the altitude of 6350 m, which is by far lower than others. Lower temperature has a significant effect on ice core record and favors the preservation of climate information.
  • PU Jian-chen, YAO Tan-dong, DUAN Ke-qin
    JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY. 2003, 25(6): 680-684. https://doi.org/10.7522/j.issn.1000-0240.2003.0120
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    During July 4 to August 8 in 2001, an observation of glacier ablation was made on the area between 4 460 m to 4 600 m a.s.l on the terminus of the Yangbark Glacier on the west of the Muztag Ata. Based on the observation, the ablation features are discussed in this paper. There existed a short warmer period on the glacier, with the maximum ablation mainly in July 21~22 and the maximum daily net ablation of about 144.5 mm water equivalent (w.e.) and 59.5 mm w.e. at the altitude of 4 460 m and 4 600 m a.s.l., respectively. The total net ablation reached to about 640~1 260 mm w.e. and the mean daily ablation about 26~32.8 mm w.e. during this period. Therefore, the annual net ablation is estimated about 1 700~2 000 mm w.e. in this region, which was far more than that of the glaciers on the inner Tibetan Plateau. Meanwhile, the ablation generally decreases with altitude. The ablation gradient is about 0.40~0.55 mm·10 m-1 on the bare ice and 0.21~3.53 mm/10 m on the debris-covered ice. So, the mean daily net ablation at the 4 800 m a.s.l. can be calculated from the ablation gradient on the bare ice. The glacier ablation continuously increases as compared with the observation in 1960 and 1987, according to the background of global warming.
  • YANG Hui-an, LI Zhong-qin, YE Bai-sheng, JIAO Ke-qin
    JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY. 2003, 25(6): 685-691. https://doi.org/10.7522/j.issn.1000-0240.2003.0121
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    The result of supplemental glacier inventory and the features of glaciers in the basin of the Bangong Lake in China are described in this paper. The former inventory was based on 1: 1 000 000 satellite images. It is renewed by using air photographs of 1980 and 1: 50 000 topography map of 1983.The new glacier inventory and background data becomes more perfect and trustier. The former showed that there were 834 glaciers with a total area of 642.77 km2 and a total volume of ice was 33.9246 km3 in the basin of the Bangong Lake. The new result shows that the number of glaciers is 959 with a total area of 665.35 km2 and a total ice volume of 39.2316 km3. The main reason which caused the former inventory resulting in less glaciers is some small glaciers, of which the area is≤1 km2, were missing.
  • LONG Ai-hua, XU Zhong-min, ZHANG Zhi-qiang
    JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY. 2003, 25(6): 692-700. https://doi.org/10.7522/j.issn.1000-0240.2003.0122
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    Water footprint is a new concept reflecting people’s real consumption and usage of water resources. It profoundly posts the real water consumption of social-economic system and offers a new viewpoint for water resource management. In this paper, the concept of water footprint is put forward, together with its calculation methodologies. As a case, the water footprint of Northwest China including Xinjiang Region, Qinghai, Gansu and Shanxi provinces in 2000 is quantified and analyzed, mainly based on the concept of virtual water and its quantification methods. The result shows that citizens in these provinces (region) in 2000 have consumed 613.3×108m3 water resource in total, which means 713.3 m3/year per capita and 1952L /day per capital, exceeding the statistical volume of usage. The water footprint based on the virtual water not only reflects the actual water occupations of human beings, but also has great importance for water management in arid regions in Northwest China, and gives the water management decision-maker a bran-new thought of solving the water scarcity and innovation of water management mechanisms to balance the water deficit and achieve regional water and food security, by improving the water usage efficiency to changing living mode, and by applying virtual water import strategy instead of water supply-side management.
  • XU Zhong-min, REN Fu-kang, MA Song-yao, GUO Ting-tian
    JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY. 2003, 25(6): 701-707. https://doi.org/10.7522/j.issn.1000-0240.2003.0123
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    The use of stated preference techniques for estimating environmental value has increased substantially in recent years. However, criticizing the most widespread stated preferences used for valuing environmental resources, the contingent valuation method (CVM) suggests that there is a need to not only refine the CVM, but also to develop alternative stated preferences techniques. In this paper, the CVM is compared with four other stated preferences: contingent rating, contingent ranking, paired comparison and choice modeling. The techniques are compared in terms of their methodologies and the validity and reliability of the results they produce. The appropriateness of using each of the stated preferences techniques in different environmental valuation applications is also discussed. It is concluded that while the CVM is prone to bias and has some practical limitations, when applied appropriately it can be used to produce theoretically valid results. Three of the other techniques such as contingent rating, contingent ranking and paired comparison are found to have weak theoretical bases and do not produce economically valid valuation estimates. The final stated preferences technique examined, choice modeling, appears to have considerable potential for providing useful and valid estimated of environmental values.
  • WU Shu-fen, HAN Ping, LI Yan, XUE Yan, ZHU Ye-chao
    JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY. 2003, 25(6): 708-711. https://doi.org/10.7522/j.issn.1000-0240.2003.0124
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    Based on the annual runoff variation over the past 40 a in the headwaters of the Tarim River and by analyzing the factors impacting annual runoff, air temperature and precipitation are selected as the prediction factors. Using PPR model, water resources are predicted of the Tarim River when climate shifts to warm humid. It is predicted that as long as temperature rising 0.5~2 ℃, water resources of the 5 streams in the headwaters will increase with temperature rising; As precipitation increasing 10%~30%, annual runoff in the rivers, of which glacier meltwater accounts for a large portion, will decrease with precipitation increasing; When temperature rises 2 ℃ and precipitation increases 10%~30%,annual runoff will increase, but it will decrease again as precipitation increasing more.
  • WANG Shun-de, LI Hong-de, XU Ze-rui, HAN Ping, WANG Jin
    JOURNAL OF GLACIOLOGY AND GEOCRYOLOGY. 2003, 25(6): 712-718. https://doi.org/10.7522/j.issn.1000-0240.2003.0125
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    The Tarim River Basin is located in the southern half of Xinjiang Uygur Autonomous Region, PRC. From the confluence of its three main contributing tributaries, the Tarim River mainstream extends 1321 km to Taitema Lake. The mainstream can be classed into the upstream with 495 km from Xiaojiake to Yinbazar, the middlestream with 398 km from Yinbazar to Kara and the lowerstream with 428 km from Kara to Taitema Lake. A number of rivers fed by snowmelt and glacier melt begin in the mountains and drain into the basin with average annual virgin flow of about 35 billion m3. A number of other subbasins exist within the Tarim Basin that does not contribute flows to the Tarim River because all of their flows either naturally evaporate in the desert or are used in irrigated agriculture areas. Peak flow months in the rivers are July, August and September. Lowest flow occurs in the period from January through April. Total streamflow of the four headstreams of the Tarim River in 2001 is 266.5×108m3, more 40.70×108m3 than annual mean streamflow, increasing 18% to annual mean value. Annual mean streamflow at Aler Gauging Station where the Tarim River mainstream begins was 46.00×108m3. The interzone consumed water of the Tarim River mainstream are estimated to be 15.33×108m3 for the upper course, account for 33.3% of Aler annual mean streamflow; 23.99×108m3 for the middle course, 52.2% of Aler ones and 6.680×108m3 for the downstream course,14.5% of Aler ones. The consumed water of both upstream and middlestream courses sum up 39.32×108m3, account for 85.5% of annual mean streamflow at Aler Gauging Station. Historical annual flows average over 40×108m3, but for the past two decades there has essentially been no flow below Daxihaizi Reservoir, 300 km upstream of Taitema Lake. In 2001, an emergency water diversion project was carried out in the "green corridor", transfer water from Bosten Lake to the Taitema Lake, and fed the "green corridor", ended the 30-years no flow history of 300 km upstream of the Taitema Lake, and ecological environment started to be restoring.