检索结果-南通市图书馆

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

在线全文

学校读者我要写书评

暂无评论

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 research {3., 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 20th 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 20th 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

在线全文

学校读者我要写书评

暂无评论

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 research ,{3. , lanzhou 730000, china Xi an Laboratory of Loess and Quaternary Geology,{3. , Xi’ an 710054, china institute of Loess Plateau , Shanxi University, Taiyuan 03.006, china institute of desert research 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 S1 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.

research progress of desert science in china

在线全文

学校读者我要写书评

暂无评论

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 academy of sciences, Urumqi 83.011, china Cold and Arid Region Environment and Engineering {3. institute. chinese academy 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 china began in the 193.s, 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 china

关键词： research progress of desert science in china

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

在线全文

学校读者我要写书评

暂无评论

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

作者： WEI WenshouXinjiang institute of Ecology and Geography, chinese academy of sciences, Urumqi 83.011, china Open Laboratory of Ice-Core, Cold and Arid Regions Environmental and Engineering {3. institute, chinese academy 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.

Preliminary results of the study on wind erosion in the Qinghai-Tibetan Plateau using 13.Cs technique

在线全文

学校读者我要写书评

暂无评论

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. institute of {3. research, 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 research 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-13. (13.Cs) 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 13.Cs technique is introduced into the studies of wind erosion and its modern processes inthe Qinghai-Tibetan Plateau. Two 13.Cs reference inventories of 982.11 and 2 3.6.04 Bq · m-2 wereestablished preminarily, distributed in the south and middle-north parts of the studied arearespectively. By analyzing the patterns of 13.Cs 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 13.Csmodel, the average wind erosion rates for shrub coppice

关键词： 13.Cs technique Qinghai-Tibetan Plateau wind erosion.

^(13.)Cs tracing of lacustrine sediments in the Dalian Lake,Qinghai Province,china

在线全文

学校读者我要写书评

暂无评论

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

作者： VAN Ping, DONG Guangrong & DONG Zhibaochina Certer of desert research at Beijing Normal University, Beijing100875,{3.:Key Laboratory of Environmental Change and Natural Disaster, the Ministry of Education of{3., Beijing Normal University, Beijing 100875,{3. Cold and Arid Regions Environmental and Engineering research institute, chinese academy of sciences, lanzhou 730000,{3. china Certer of desert research 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 13.Cs deposition by wind and water in the Dalian Lake of Gonghe Basin, Qinghai Province are defined. The vertical profile of 13.Cs in the lacustrine sediments exhibits three 13.Cs activity maxima and one minimum. The major maximum corresponds to the global I3.Cs 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 13.Cs 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 l3.Cs has the same potential to trace environmental changes introduce by human interference in arid/semiarid regions as in humid regions.

关键词： 13.Cs technique Dalian Lake sedimentation rate.

Effects of the Extract of Ammopiptanthus mongolicus cheng f. (JA1) on Induction of Apoptosis of HepG2 in vitro and Its Molecular Mechanisms

在线全文

学校读者我要写书评

暂无评论

Biomedical and Environmental sciences 2006年第2期19卷 118-123页

作者： LEI JIA LI-ZHE AN Key Laboratory of Arid and Pastoral Agroecology of Ministry of Education and School of Life sciences LanzhouUniversity Lanzhou 730000 Gansu China Key Laboratory of desert and desertification Cold and Arid Region Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 Gansu China

Objective To study the effects and the mechanisms of extract from a leguminous plant （Ammopiptanthus mongolicus cheng f.）（JAl ） in northwest china on inducing apoptosis and inhibiting proliferation of HepG2 hepatocarcinoma cell in vitro. Methods The HepG2 cell line was used as target cells. The effect of 3. 1 on HepG2 cell growth was detected by microculture tetrazolium assay （MTr）, flow cytometry assay, DNA agarose gel electrophoresis and transmission electronic microscopy. The expressive effect of the wt-p53.in HepG2 cells was analyzed with p53.protein test-reagent. Results JAl not only had significant anti-proliferative effects depending upon time and dosage, but also induced apoptosis of HepG2 cells. Apoptotic typical morphological changes were observed in JAl-treated HepG2 cells under transmission electronic microscope, ＂Sub-G 1＂ phase peak occurred in flow cytometry and DNA ＂ladder＂ was found in DNA agarose gel electrophoresis. The expression of the wt-p53.increased in vitro, and 3.l-treated HepG2 and the positive cell percentage of the wt-p53.protein also increased. Conclusions JAl could obviously induce apoptosis and inhibit proliferation of HepG2 cells in vitro, and these effects are closely related with the increase of wt-p53.expression. JAl can be used as a good source of medicinal plant for the treatment of hepatocarcinoma.

关键词： Extract from Ammopiptanthus mongolicus cheng f. (JAl) HepG2 Apoptosis Induction wt-p53

Progress in studies of the climate of humid period and the impacts of changing precession in early-mid Holocene

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2008年第12期18卷 1459-1464页

作者： Jianbin Huang~a Shaowu Wang~a Xinyu Wen~a Bao Yang~b a Department of Atmospheric sciences,School of Physics,Peking University,Beijing 100871,china b Laboratory for desert and desertification,Cold and Arid Regions Environmental and Engineering research institute,chinese academy of sciences,lanzhou 730000,china Department of Atmospheric sciences School of Physics Peking University Beijing 100871 China Laboratory for desert and desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

Studies on the climate of humid period and the impacts of changing precession in the early-mid Holocene are reviewed in this paper. High-resolution proxy data indicated that the African Humid Period,strong summer monsoon from the Arabian Sea to South Asia, northward migration of ITCZ (lntertropical Convergence Zone) over the northern South America,and the humid period of china appeared in 10.5-5.5 kaBP,10.0-6.0 kaBP,10.5 5.4 kaBP,and 11.0-8.0 kaBP,*** studies proved that summer inso- lation over the Northern Hemisphere increased following the changes of precession in the early Holocene,which increased the land-sea temperature contrasts,intensified the summer monsoon circulation in the Northern Hemisphere,and finally induced a humid climate over the area under the influence of summer ***,modeling results underestimated the increase of precipitation and the degree of northward extension of monsoon rain belt compared with palaeo-environmental *** discrepancies between the modeling results and the palaeo-environmental data may be associated with the changes of North Atlantic circulation,sea ice and veg- etation ***,climate of the humid period was not stable,in which several droughts were inlaid on centennial *** this review,perspectives for further studies of the climate change of the humid period in the early-mid Holocene are also proposed.

关键词： Holocene Humid period Precession Summer monsoon

Preliminary reconstruction of the desert and sandy land distributions in china since the last interglacial period

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science china Earth sciences 2004年第Z1期47卷 89-100页

作者： CHEN Huizhong, SU Zhizhu, YANG Ping & DONG GuangrongKey Laboratory of desert and desertification, Cold and Arid Regions Environmental and Engineering research {3., chinese academy of sciences, lanzhou 730000, china State Key Laboratory of Loess Quaternary Geology, {3. of Earth Environment, chinese academy of sciences, Xi’an 710075, china {3. of Loess Plateau, Shanxi University, Taiyuan 03.006, china Key Laboratory of desert and desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China State Key Laboratory of Loess Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China institute of Loess Plateau Shanxi University Taiyuan China

The desert and sandy land are the products of arid climate. The spatial distribution of modern deserts and sandy land in china and their relation to climate show following characteristics: arid and hyper-arid desert zones, at isohyet of less than 200 mm, are dominated by mobile dunes; semi-arid steppe and arid desert steppe with the precipitation between 200-400mm, are dominated by semi-fixed and fixed sand dunes; the precipitation of sub-humid forest grassland and humid forest zones with scattered fixed sand land is higher than 400 mm. With this as reference, in combination with considerable amount of paleoclimatic data in desert regions and adjacent regions, the distributions of desert and sandy land in china during the last interglacial period, the last glacial maximum (LGM), and the Holocene megathermal, were preliminarily reconstructed. The results compared with that of today show that the distribution of desert and sandy land in china was greatly dwindled during last interglacial period, and the mobile dune area was about two-thirds of that of today's, but greatly expanded during LGM. However, the dwindling area of desert and sandy land in the Holocene megathermal was smaller than that in the last interglacial period. The forcing mechanism was mainly related to the changes of East Asian winter and summer monsoon, south-northward swing of the westerlies and the variations of the Qinghai-Tibet Plateau monsoon intensity caused by global climate changes during the cold and warm intervals since the last interglacial period.

关键词： the glacial-interglacial period, desert, sandy land, spatial distribution.