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Vicissitude of sogo Nur and environmental-climatic change during last 1500 years

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science china Earth sciences 2004年第z1期47卷 61-70页

作者： JIN Heling, XIAO Honglang, sUN Liangying, ZHANG Hong, sUN Zhong & LI XiaozeKey Laboratory of desert and desertification, Cold and Arid Regions Environmental and Engineering {2. institute, chinese academy of sciences, lanzhou 730000, china school of Resources and Environment, lanzhou University, lanzhou 730000, china Key Laboratory of desert and desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China school of Resources and Environment Lanzhou University Lanzhou China

Lakes in arid zone are sensitive to climatic changes. The lacustrine sediment sequence in sogo Nur has well and truly recorded climatic events such as the sui-Tang Dynasty Warm Period, the song-Liao Dynasty Cold Period, the Medieval Warm Period, the Little Ice Age and the 2.th Century Warm Period. Commonly, the climate in warm Periods was relatively humid,accordingly the lake area extended and water level rose, and vice versa. Apart from climatic change, human activity is also an important factor of influencing lake vicissitude, and they played the dominant role alternatively during different periods; the factor of climatic change predominated in historical period, while since the beginning of the 2.th century the utilization of water resources by human has became decisive.

关键词： granularity, soluble salt, lake vicissitude, climatic change, sogo Nur.

New views on age of the salawusu Formation of Late Pleistocene in northern china

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chinese science Bulletin 1999年第7期44卷 646-650页

作者： DONG Guangrong, sU Zhizhu and JIN Heling institute of desert {2. , chinese academy of sciences , lanzhou 730000, china Xi an Laboratory of Loess and Quaternary Geology, chinese academy of sciences , Xi’ an 710054, china institute of Loess Plateau , shanxi University, Taiyuan 030006, china institute of desert {2. Chinae Academy of Sciences Lanzhau China Xi’an Laboratory of Lass and Quaternary Geology Chinese Academy of Sciences Xi’an China institute of Lass Plateau Shanxi University Taiyuan China

The salawusu Formation in the salawusu River basin of Inner Mongolia is a typical sequence of the Upper Pleistocene in northern china. However, there have been some different views about the division and age of stratigraphic facies since the establishment of the salawusu Formation. According to the stratigraphic subdivision and dating of the Dishaogouwan section, it is thought that the fluviolacustrine-aeolian sand sequence from the Dishaogouwan section can be compared with loess, deep-sea deposit records and climatic fluctuations of glacial period. The salawusu Formation of fluviolacustrine facies was formed in the last interglacial period from 140 to 70 ka BP, roughly corresponding to the fifth stage of deep-sea oxygen isotope, and developed in the same period as the palaeosol ssub>1sub> on the Loess Plateau; the aeolian sand of the Chengchuan Formation was formed in the last glacial period from 70 to 10 ka BP, constituting the heteropic geological body along with the Malan Loess on the Loess Plateau; the

关键词： salawusu Formation age deep-sea oxygen isotope.

Preliminary results of the study on wind erosion in the Qinghai-Tibetan Plateau using 137Cs technique

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chinese science Bulletin 2000年第11期45卷 1019-1025页

作者： YAN Ping, DONG Guangrong, ZHANG Xinbao & ZHANG Yiyun1. Key Laboratory of Environmental Change and Natural Disaster, the Ministry of Education of china, Beijing Normal University, Beijing 100875, china {2., chinese academy of sciences, lanzhou 730000, china 3. institute of Mountain Hazards and Environment, chinese academy of sciences, Chengdu 610041, china 4. Department of Physics, sichuan Union University, Chengdu 610041, china Key Laboratory of Environmental Change and Natural Disaster the Ministry of Education of China Beijing Normal University Beijing China institute of desert {2. Chinese Academy of Sciences Lanzhou China institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu China Department of Physics Sichuan Union University Chengdu China

The worldwide fallout of caesium-137 (137Cs) associated with the nuclear weapon tests during the 1950s and 1960s has provided a valuable man-made tracer for studies of soil erosion and sediment delivery. But relatively few researchers have used it to estimate wind erosion. In this note, the 137Cs technique is introduced into the studies of wind erosion and its modern processes inthe Qinghai-Tibetan Plateau. Two 137Cs reference inventories of 982.11 and 2.376.04 Bq · m-2.wereestablished preminarily, distributed in the south and middle-north parts of the studied arearespectively. By analyzing the patterns of 137Cs depth profiles from sampling sites, the aeolianprocesses of erosion and deposition in nearly 40 years have been revealed, i.e. the shrub coppicedunes (s1) and semi-fixed dunefields (s3) experienced the alternation of erosion and deposition,while the grasslands (s4, s6 and s7) and dry farmlands (s5) suffered erosion only. By using 137Csmodel, the average wind erosion rates for shrub coppice

关键词： 137Cs technique Qinghai-Tibetan Plateau wind erosion.

Respondence and feedback of modern sand deserts to climate change ——A case study in Gurbantunggut desert

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chinese science Bulletin 2000年第12期45卷 1137-1142页

作者： WEI WenshouXinjiang institute of Ecology and Geography, chinese {2. of sciences, Urumqi 830011, china Open Laboratory of Ice-Core, Cold and Arid Regions Environmental and Engineering research institute, chinese {2. ofsciences, lanzhou 730000, china Xinjiang institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China Open Laboratory of Ice-Core Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

The research on the respondence and feedback of modern sand deserts to the climate change is an important component part in the studies on the global climate change. deserts respond to the climate change, meanwhile, they affect the climate with their feedback of peculiar environment during the respondence. Many researches on desert climate have been carried out at home and abroad. However, there is little research on the respondence and feedback of modern fixed, semi-fixed and mobile deserts in arid areas to the climate change, in which the factor analysis as well as the parameter changing effects is especially the difficult problem all along. In this note, the parameters of the respondence and feedback of Gurbantunggut desert to the climate change are measured and analyzed, some variable parameters of water-heat exchange are obtained, and a numerical model of desertification is developed according to a series of climate change of about 40 years and the variable relations of meteorological and physical

关键词： Gurbantunggut desert climate change respondence and feedback numerical model.

research progress of desert science in{2.

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chinese science Bulletin 2000年第24期45卷 2209-2213页

作者： XIA Xuncheng & FAN shengyueXinjiang institute of Ecology and Geography, chinese {2. of sciences, Urumqi 830011, china Cold and Arid Region Environment and Engineering research institute. chinese {2. of sciences, lanzhou 730000. china Xinjiang institute of Ecology and Geography Chinese Academy of Sciences Urumqi China Cold and Arid Region Environment and Engineering research Instiute Chinese Academy of Sciences Lanzhou China

research of desert science in{2. began in the 1930s, when Chen Zongqi et al. first made apreliminary investigation in several deserts. shortly after the founding of the People’s Republic ofchina a few studies were carried out to meet the demand for the establishment of windbreak andsandbreak forests, for example, the studies of moving sand dunes in Yulin. Jingbian and Dingbianregions of shaanxi Province. However, the comprehensive study of desert science in{2.

关键词： research progress of desert science in{2.

On the sand surface stability in the southern part of Gurbantünggüt desert

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中国科学：地球科学英文版 2005年第6期48卷 778-785页

作者： WANG Xueqin1,2. WANG Tao1, JIANG Jin2.& ZHAO Congju2.1. Laboratory of Blown sand Physics and desert Environment, Cold and Arid Regions of Environmental and Engineering research In-stitute, {2. academy of sciences, lanzhou 730000, china 2. Xinjiang institute of Ecology and Geography, {2. academy of sciences, Urmqi 830011, china Correspondence should be addressed to Wang Xueqin Laboratory of Blown sand Physics and desert Environment Cold and Arid Regions of Environmental and Engineering Research In-stitute Chinese Academy of Sciences Lanzhou China Xinjiang institute of Ecology and Geography Chinese Academy of Sciences Urümqi China

Longitudinal dunes are the most widespread dune types in the world sand seas but comprehensive study on the sand surface stability is scarce. The southern part of Gurbantnggt desert is mainly covered by longitudinal dune in which fixed and semi-fixed dunes occupy over 80% of the total area. systematic analysis on the climatic conditions, the soil moisture and vegetation distributions, and the sand surface activities showed that the fixed and semi-fixed dunes are in a comprehensive low-energy wind environment. snow cover and frozen soil provide a good protection to the ground surface in winter. The temporal distribution of precipitation and corresponding variation of temperature create a favorable condition for the desert plants growth, especially for the ephemeral plants. The occurrence of effective winds for sand moving in April to June coincides with the stage of relatively wet sand surface and good vegetation cover, which effectively keep the sand surface stable at the interdune and the plinth of the dunes. Activity sand surface appears only at the crest and the upper part of the sand dunes.

关键词： Gurbantünggüt desert, longitudinal dune, sand surface stability.

Magnetic characteristics of dustfall in urban area of north china and its environmental significance

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science china Earth sciences 2007年第11期50卷 1724-1732页

作者： XIA Dunsheng1,2. YANG LiPing2. MA JianYing1, YU Ye1, WANG Guan2.& CHEN FaHu2.1 Key Laboratory of desert and desertification, {2. of Cold and Arid Regions Environmental and Engineering, chinese academy of sciences, lanzhou 730000, china 2.CAEP, Key Laboratory of West china’s Environmental system (Ministry of Education), lanzhou University, lanzhou 730000, china Key Laboratory of desert and desertification Institute of Cold and Arid Regions Environmental and Engineering Chinese Academy of Sciences Lanzhou China CAEP Key Laboratory of West China’s Environmental System (Ministry of Education) Lanzhou University Lanzhou China

Urban particulate pollutants not only affect urban air quality but also directly threaten public health. lanzhou has been one of the most seriously polluted cities in the world due to its special geophysical location and weather conditions, which makes it an ideal place for urban particulate pollution study. In this study a set of environmental magnetic parameters (χ_(1f),χ_(fd)%, χ_(ARM), sIRM, HIRM, sOFT and back field IRM) were measured and analyzed for the dustfall samples collected monthly during 1997.4—2.00.5 and 2.04.11—2.05.10 at lanzhou University campus (KLD and CCs) and at a clear site of Gaolanxian (GLX). Results demonstrate that the main magnetic minerals in the dustfall are magnetite, with some maghaemite and haematite. Cross plots of M_(rs)/M_s vs. B_(cr)/B_c and χ_(fd)% vs. χ_(ARM)/sIRM indicate that the main magnetic grain sizes are pseudo-single-domain (PsD). The high concentration of magnetic minerals in the dustfall indicates that lanzhou is seriously polluted. The main pollution sources are anthropogenic activities and nature dust, with the former posing a great threat during the whole year, which is different from the general view that the natural dust is the main contributor in summer. With great efforts of the government and local authority in the past decades, the air quality in lanzhou has been improved in winter, but it is not so obvious in summer. This study also reveals that as a simple, rapid and accurate technology, environmental magnetism could be a valuable tool for urban pollution study.

关键词： environmental magnetism,dustfall,air pollution,lanzhou

^(137)Cs tracing of lacustrine sediments in the Dalian Lake,Qinghai Province,china

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chinese science Bulletin 2001年第S1期46卷 83-87页

作者： VAN Ping, DONG Guangrong & DONG Zhibaochina Certer of desert {2. at Beijing Normal University, Beijing100875, china:Key Laboratory of Environmental Change and Natural Disaster, the Ministry of Education of china, Beijing Normal University, Beijing 100875, china Cold and Arid Regions Environmental and Engineering {2. institute, chinese academy of sciences, lanzhou 730000, china china Certer of desert {2. at Beijing Normal University Beijing China Key Laboratory of Environmental Change and Natural Disaster The Ministry of Education of China Beijing Normal University Beijing China Cold and Arid Regions Environmental and Engineering research institute Chinese Academy of Sciences Lanzhou China

Based upon the analysis of Cs and grain-size parameters, the total amounts of 137Cs deposition by wind and water in the Dalian Lake of Gonghe Basin, Qinghai Province are defined. The vertical profile of 137Cs in the lacustrine sediments exhibits three 137Cs activity maxima and one minimum. The major maximum corresponds to the global I37Cs fallout in 1963; the two secondary maxima correspond to the leakage of the Chernobyl reactor in 1986 and complete desiccation of the lake in 1994, respectively. The minimum corresponds to aeolian deposition caused by extensive reclamation in the late 1980s and early 1990s. The 137Cs data set was used to evaluate average sedimentation rate of the Dalian Lake since 1963. The deposition was stable in 1963-1986 and 1994-1998, and it was rapid during 1986?994. This preliminary study reveals that l37Cs has the same potential to trace environmental changes introduce by human interference in arid/semiarid regions as in humid regions.

关键词： 137Cs technique Dalian Lake sedimentation rate.

A high-resolution late Pleistocene record of pollen vegetation and climate change from Jingning, NW china

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science china Earth sciences 2006年第2期49卷 154-162页

作者： LI Chunhai12. TANG Lingyu1, FENG Zhaodong3,4, ZHANG Hucai2. WANG Weiguo3 & AN Chenbang3 1. Nanjing institute of Geology and Palaeontology, chinese {2. of sciences, Nanjing 2.0008, china 2. Nanjng institute of Geography and Limnology, chinese {2. of sciences, Nanjing 2.0008, china 3. Environment and Resources College, lanzhou University, lanzhou 730000, china 4. Beijing Normal University, Beijing 100875, china Nanjing institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China Nanjng institute of Geography and Limnology Chinese Academy of Sciences Nanjing China Environment and Resources College Lanzhou University Lanzhou China Beijing Normal University Beijing China

With the support of 18 AMs-14C data, a high-resolution pollen record from the suancigou section at Jingning, Gansu Province was established. Our results showed that the vegetation ex-perienced a series of changes characterized by the alternative growth and decline of forest and steppe components during the period from 44.2.to 11 ka B.P. in the Jingning area. Over the period of 44―2. ka B.P. (MIs3), coniferous forests were flourishing, indicating a humid climate with the tem-perature being lower than that of the present. since 2. ka B.P., the vegetation was dominated by steppe-desert steppe under a cold and dry condition, and entered the Last Glacial Maximum domi-nated by desert steppe. several periods of the marked decrease in the arborous pollen content in suancigou well corresponded to the North Atlantic Heinrich events, especially to Heinrich event 3, further supporting that the Heinrich events were well reflected by the pollen record in the Loess Pla-teau as well.

关键词： Western Loess Plateau, pollen record, climatic change, late Pleistocene.