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Thermal regimes and degradation modes of permafrost along the Qinghai-Tibet Highway

Science China Earth Sciences 2006年第11期49卷 1170-1183页

作者： JIN Huijun ZHAO Lin wang shaoling JIN Rui State Key Laboratory of Frozen Soils Engineering and Cryosphere Station of the Qinghai-Tibet Plateau Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of SciencesLanzhou 730000 China

Permafrost on the Qinghai-Tibet Plateau (QTP) is widespread, thin, and thermally unstable. Under a warming climate during the past few decades, it has been degrading extensively with generally rising ground temperatures, the deepening of the maximum summer thaw, and with lessening of the winter frost penetration. The permafrost has degraded downward, upward and laterally. Permafrost has thinned or, in some areas, has totally disappeared. The modes of permafrost degradation have great significance in geocryology, in cold regions engineering and in cold regions environmental management. Permafrost in the interior of the QTP is well represented along the Qing-hai-Tibet Highway (QTH), which crosses the Plateau through north to south and traverses 560 km of permafrost-impacted ground. Horizontally, the degradation of permafrost occurs more visibly in the sporadic permafrost zone in the vicinity of the lower limit of permafrost (LLP), along the margins of taliks, and around permafrost islands. Downward degradation develops when the maximum depth of seasonal thaw exceeds the maximum depth of seasonal frost, and it generally results in the formation of a layered talik disconnecting the permafrost from the seasonal frost layer. The downward degrada- tion is divided into four stages: 1) initial degradation, 2) accelerated degradation, 3) layered talik and 4) finally the conversion of permafrost to seasonally frozen ground (SFG). The upward degradation occurs when the geothermal gradient in permafrost drops to less than the geothermal gradients in the underlying thawed soil layers. Three types of permafrost temperature curves (stable, degrading, and phase-changing transitory permafrost) illustrate these modes. Although strong differentiations in local conditions and permafrost types exist, the various combinations of the three degradation modes will ultimately transform permafrost into SFG. Along the QTH, the downward degradation has been proceeding at annual rates of 6 to 25

关键词： QTP QTH permafrost ground temperatures degradation modes geothermal gradients.

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Thawing and freezing processes of active layer in Wudaoliang region of Tibetan Plateau

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Chinese Science Bulletin 2000年第23期45卷 2181-2187页

作者： Lin Zhao Guodong Cheng Shuxun Li Xinmin Zhao shaoling wang Chinese Acad Sci Inst Cold & Arid Reg Environm & Engn Res State Key Lab Frozen Soil Engn Lanzhou 730000 Peoples R China

The interaction between permafrost and atmosphere is accomplished through transfer of heat and moisture in the overlay active layer. Thus, the research on the thermal and hydrodynamics of active layer during the thawing and freezing processes was considered a key to revealing the heat and moisture exchanges between permafrost and atmosphere. The monitoring and research on active layer were conducted because permafrost occupies about two thirds of the total area of the Tibetan Plateau. Based on the analysis of the ground temperature data and soil moisture data of monitoring near the Wudaoliang region of the Tibetan Plateau, the thawing and freezing processes of active layer were divided into four stages, i.e. summer thawing stage (ST), autumn freezing stage (AF), winter cooling stage (WC) and spring warming stage (SW). Coupled heat and water flow is much more complicated in ST and AF, and more amount of water is migrating in these two stages. Heat is transferred mainly via conductive heat flow in the

关键词： active layer freezing process water and heat couple.

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Monitoring of frozen soil hydrology in macro-scale in the Qinghai-Xizang Plateau

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Chinese Science Bulletin 2000年第12期45卷 1143-1149页

作者： Yongjian Ding Baisheng Ye Shiying Liu Yongping Shen shaoling wang Meixie Yang Chinese Acad Sci Lanzhou Inst Glaciol & Geocryol Lanzhou 730000 Peoples R China

Monitoring of frozen soil hydrology in macro-scale was performed by Chinese and Japanese scientists from 1997 to 1998. Quality measured data were obtained. Measured data on soil moisture and temperature are preliminarily analyzed. Based on profiles of soil temperature and moisture in individual measured sites, intra-annual freezing and melting process of soil is discussed. Maximum frozen and thawed depths and frozen days in various depths are estimated. The work emphasized the spatial distribution on soil temperature and moisture in macro-scale and the effect of topography on conditions of soil water and heat.

关键词： active layer of frozen soil soil temperature soil moisture monitoring in macro-scale.

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Bacteremia complicated with pneumonia caused by Corynebacterium diphtheriae

Infectious Medicine

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Infectious Medicine 2022年第4期1卷 276-280页

作者： Xiaojun Zhou Xuebing wang Hua Wua Meihui Huang shaoling wang Xuming wang Haijian Zhou Department of Clinical Laboratory Hainan General HospitalHainan Affiliated Hospital of Hainan Medical UniversityHaikou570311China State Key Laboratory of Infectious Disease Prevention and Control National Institute for Communicable Disease Control and PreventionChinese Center for Disease Control and PreventionChangpingBeijing102206China Hainan Center for Disease Control and Prevention Haikou570203China

Due to the use of vaccines,infections caused by Corynebacterium diphtheriae are now *** we describe a case of bacteremia complicated with pneumonia caused by *** in a 69-year-old male *** patient presented at the emergency department with a 2 days history of fever of unknown *** examinations revealed pneumonia and ***-toxigenic *** strains were isolated from blood and *** patient had antimicrobial therapy with good *** highlight the important role of *** in causing bacteremia and pneumonia,and its accurate and timely diagnosis is needed to avoid poor visual outcomes.

关键词： Corynebacterium diphtheriae Pneumonia Bacteremia China

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Evolution of permafrost in China during the last 20 ka

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Science China Earth Sciences 2019年第8期62卷 1207-1223页

作者： Huijun JIN Xiaoying JIN Ruixia HE Dongliang LUO Xiaoli CHANG shaoling wang Sergey S MARCHENKO Sizhong YANG Chaolu YI Shijie LI Stuart A HARRIS Northeast China Observational Station of Cold-regions Engineering and Environment State Key Laboratory of Frozen Soils EngineeringNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China School of Civil Engineering Harbin Institute of TechnologyHarbin150090China School of Resources and Environment University of Chinese Academy of ScienceBeijing100049China Hunan University of Science and Technology Xiangtan411201China Permafrost Laboratory Geophysical InstituteUniversity of Alaska FairbanksFairbanksAK99775USA GFZ German Research Centre for Geosciences TelegrafenbergPotsdam D-14473Germany Institute of Tibetan Plateau Research Chinese Academy of SciencesBeijing100010China Institute of Geochemistry Chinese Academy of SciencesGuiyang550081China Department of Geography University of CalgaryCalgaryAlberta T2N1N4Canada

The formation and evolution of permafrost in China during the last 20 ka were reconstructed on the basis of large amount of paleo-permafrost remains and paleo-periglacial evidence, as well as paleo-glacial landforms, paleo-flora and paleofauna records. The results indicate that, during the local Last Glacial Maximum(LLGM) or local Last Permafrost Maximum(LLPMax), the extent of permafrost of China reached 5.3×106-5.4×106 km2, or thrice that of today, but permafrost shrank to only0.80×106-0.85×106 km2, or 50% that of present, during the local Holocene Megathermal Period(LHMP), or the local Last Permafrost Minimum(LLPMin). On the basis of the dating of periglacial remains and their distributive features, the extent of permafrost in China was delineated for the two periods of LLGM(LLPMax) and LHMP(LLPMin), and the evolution of permafrost in China was divided into seven periods as follows:(1) LLGM in Late Pleistocene(ca. 20000 to 13000-10800 a BP)with extensive evidence for the presence of intensive ice-wedge expansion for outlining its LLPMax extent;(2) A period of dramatically changing climate during the early Holocene(10800 to 8500-7000 a BP) when permafrost remained relatively stable but with a general trend of shrinking areal extent;(3) The LHMP in the Mid-Holocene(8500-7000 to 4000-3000 a BP)when permafrost degraded intensively and extensively, and shrank to the LLPMin;(4) Neoglaciation during the late Holocene(4000-3000 to 1000 a BP, when permafrost again expanded;(5) Medieval Warming Period(MWP) in the late Holocene(1000-500 a BP) when permafrost was in a relative decline;(6) Little Ice Age(LIA) in the late Holocene(500-100 a BP), when permafrost relatively expanded, and;(7) Recent warming(during the 20 th century), when permafrost continuously degraded and still is degrading. The paleo-climate, geography and paleopermafrost extents and other features were reconstructed for each of these seven periods.

关键词： Permafrost evolution Cryogenic wedge structures Local Last Glacial Maximum(LLGM) Local Holocene Megathermal Period(LHMP) China

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Cold-region environments along the China-Russia Crude Oil Pipeline and their management

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Research in Cold and Arid Regions 2010年第2期2卷 129-136页

作者： RuiXia He HuiJun Jin LanZhi L(U) shaoling wang State Key Laboratory of Frozen Soils Engineering Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of SciencesLanzhouGansu 730000China

The cold-region eco-environments along the China-Russia Crude Oil Pipeline (CRCOP) in northern Northeast China are in disequilibrium due to the combined influences of pronounced climate warming and intensive anthropogenic *** is evidenced by the sharp areal reduction and northward shifting of the boreal forests,shrinking of wetlands,enhancing of soil erosion,accelerating degradation of permafrost and deteriorating of cold-region *** degradation of permafrost plays an important role as an internal drive in the eco-environmental *** components of the cold-region eco-environments,including frozen ground,forests,wetlands and peatlands,forest fires and 'heating island effect' of rapid urbanization,are interdependent,interactive,and integrated in the boreal *** construction and long-term operation of the CRCOP system will inevitably disturb the cold-region environments along the ***,a mandatory and carefully-elaborated environ-mental impact statement is indispensable for the proper mitigation of the ensued adverse *** management,effective protection and practical rehabilitation of the damaged cold-region environments are a daunting,costly and long-term *** recommended measures for protection and restoration of permafrost eco-environments along the pipeline route include adequate investigation,assessment and monitoring of permafrost and cold-region environments,compliance of pipeline construction and operation codes for environmental management,proper and timely re-vegetation,returning the cultivated lands to forests and grasslands,and effective mitigation of forest fire hazards.

关键词： China-Russia Crude Oil Pipeline permafrost degradation cold-region eco-environments rehabilitation

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Spatiotemporal variability of permafrost degradation on the Qinghai-Tibet Plateau

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Research in Cold and Arid Regions 2011年第4期3卷 281-305页

作者： HuiJun Jin DongLiang Luo shaoling wang LanZhi Lv JiChun Wu State Key Laboratory of Frozen Soils Engineering CoM and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou Gansu 730000 China

Based on data from six meteorological stations in the permafrost regions, 60 boreholes for long-term monitoring of permafrost temperatures, and 710 hand-dug pits and shallow boreholes on the Qinghai-Tibet Plateau （QTP）, the spatiotemporal variability of permafrost degradation was closely examined in relation to the rates of changes in air, surface, and ground temperatures. The de- cadal averages and increases in the mean annual air temperatures （MAATs） from 1961-2010 were the largest and most persistent during the last century. MAATs rose by 1.3 ℃, with an average increase rate of 0.03 ℃/yr. The average of mean annual ground surface temperatures （MAGSTs） increased by 1.3 ℃ at an average rate of 0.03 ℃/yr. The rates of changes in ground temperatures were -0.01 to 0.07 ℃/yr. The rates of changes in the depths of the permafrost table were -1 to ＋10 cm/yr. The areal extent of permafrost on the QTP shrank from about 1.50× 10^6 km^2 in 1975 to about 1.26× 10^6 km^2 in 2006. About 60% of the shrinkage in area of permafrost occurred during the period from 1996 to 2006. Due to increasing air temperature since the late 1980s, warm （〉-1 ℃） permafrost has started to degrade, and the degradation has gradually expanded to the zones of transitory （-1 to -2 ℃） and cold （〈-2 ℃） permafrost. Permafrost on the southern and southeastem plateau degrades more markedly. It is projected that the degradation of permafrost is likely to accelerate, and substantial changes in the distributive features and thermal regimes of permafrost should be anticipated. However, regarding the relationships between degrading permafrost and the degradation of rangelands, it is still too early to draw reliable conclusions due to inadequate scientific criteria and evidence.

关键词： QTP permafrost degradation ground temperatures change rates

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