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chinese Science Bulletin 2005年第24期50卷 2866-2871页

作者： WANG Ninglian Key Laboratory of Cryosphere and Environment, cold and {1. regions environmental and engineering research institute, chinese academy of sciences, lanzhou 73000, china institute of Tibetan Plateau research, chinese academy of sciences, Beijing 1.0085, china Key Laboratory of Cryosphere and Environment Cold and And Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 73000 China Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China

By analyses of the dust layers in the Malan ice core from the northern Tibetan Plateau, it was found that dirty ratio in this core might be a good proxy for dust event frequency. The variations in the dirty ratio displayed a de- crease trend over the past 200 years, which implies that dust events became less frequent during the study period. The decrease trend in the variations in dust event frequency might be caused mostly by the natural processes, including increasing precipitation and weakening westerly which might be related with global warming. Furthermore, significant negative correlation was found between the dirty ratio and δ 1.O in the Malan ice core. This is highly important for studying the effect of atmospheric dust on climate change.

关键词：青藏高原马伦冰核气候变化扬尘事件发生频率

Impact of land-use change on hydrological processes in the Maying River basin, china

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Science china Earth {1. 2006年第10期49卷 1098-1110页

作者： WANG Genxu1,3, ZHANG Yu2, LIU Guimin2 & CHEN Lin3 1. institute of Mountain Hazards and Environment, chinese academy of sciences, Chengdu 610041, china 2. cold and arid regions environmental and engineering research institute, chinese academy of sciences, lanzhou 730000, china 3. Resource and Environment School, lanzhou University, lanzhou 730000, china institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu China Resource and Environment School Lanzhou University Lanzhou China cold and {1. regions environmental and engineering research institute Chinese Academy of Sciences Lanzhou China

Since the 1.60s, dramatic changes have taken place in land-use patterns characterized by the persistent expansion of cultivated land and a continuous decrease in natural woodland and grassland in the arid inland river basins of{1.. It is very important to assess the effects of such land-use changes on the hydrological processes so vital for water resource management and sustainable development on the catchment scale. The Maying River catchment, a typical arid inland watershed located in the middle of the Hexi Corridor in northwest{1., was the site chosen to investigate the hydrological responses to land-use changes. The annual runoff, base flow, maximum peak flow, and typical seasonal runoff in both spring and autumn flood periods were selected as the variables in the hydrological processes. Statistical-trend analysis and curvilinear regression were utilized to detect the trends in hydrological variables while eliminating the climatic influence. The relationship between cultivated land-use and hydrological variables was analyzed based on four periods of land-use variation data collected since 1.65. A runoff model was established composed of two factors, i.e., cultivated land use and precipitation. The impact of land use changes, especially in the large ar- eas of upstream woodland and grassland turned into cultivated lands since 1.67, has resulted in a mean annual runoff decrease of 28.1.%, a base flow decline of 35.32%, a drop in the maximum peak discharge of 35.77%, and mean discharge decreases in spring and autumn of 36.05% and 24.87% respectively, of which the contribution of cultivated land expansion to the influence of annual runoff amounts to 77%-80%, with the contribution to the influence of spring discharge being 73%-81., and that to the influence of base flow reaching 62%-65%. Thus, a rational regulation policy of land use patterns is vitally important to the sustainable use of water resources and the proper development of the entire catchment.

关键词： land-use change, arid inland river catchment, hydrological process, impact, Maying River.

Impacts of permafrost changes on alpine ecosystem in Qinghai-Tibet Plateau

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Science china Earth {1. 2006年第11期49卷 1156-1169页

作者： WANG Genxu1,3 , LI Yuanshou2 , WU Qingbai2 & WANG Yibo3 1. institute of Mountain Hazards and Environment, chinese academy of sciences, Chengdu 610041, china 2. cold and arid regions environmental and engineering research institute, chinese academy of sciences, lanzhou 730000, china 3. Resource and Environment School, lanzhou University, lanzhou 730000, china institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu China Resource and Environment School Lanzhou University Lanzhou China cold and {1. regions environmental and engineering research institute Chinese Academy of Sciences Lanzhou China

Alpine cold ecosystem with permafrost environment is quite sensitive to climatic changes and the changes in permafrost can significantly affect the alpine ecosystem. The vegetation coverage, grassland biomass and soil nutrient and texture are selected to indicate the regime of alpine cold ecosystems in the Qinghai-Tibet Plateau. The interactions between alpine ecosystem and permafrost were investigated with the depth of active layer, permafrost thickness and mean annual ground temperature (MAGTs). Based on the statistics model of GPTR for MAGTs and annual air temperatures, an analysis method was developed to analyze the impacts of permafrost changes on the alpine ecosystems. Under the climate change and human engineering activities, the permafrost change and its impacts on alpine ecosystems in the permafrost region between the Kunlun Mountains and the Tanggula Range of Qinghai-Tibet Plateau are studied in this paper. The results showed that the per- mafrost changes have a different influence on different alpine ecosystems. With the increase in the thickness of active layer, the vegetation cover and biomass of the alpine cold meadow exhibit a significant conic reduction, the soil organic matter content of the alpine cold meadow ecosystem shows an exponential decrease, and the surface soil materials become coarse and gravelly. The alpine cold steppe ecosystem, however, seems to have a relatively weak relation to the permafrost environment. Those relationships resulted in the fact that the distribution area of alpine cold meadow decreased by 7.98% and alpine cold swamp decreased by 28.1.% under the permafrost environment degradation during recent 1. years. In the future 50 years the alpine cold meadow ecosystems in different geomorphologic units may have different responses to the changes of the permafrost under different climate warming conditions, among them the alpine cold meadow and swamp ecosystem located in the low mountain and plateau area will have a relatively

关键词： permafrost environment, alpine cold ecosystem, statistics relationship, climate change, impacts, Qinghai-Tibet Plateau.

Water transfer characteristics during methane hydrate formation and dissociation processes inside saturated sand

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Journal of Natural Gas Chemistry 2010年第1期19卷 71-76页

作者： Peng Zhang, Qingbai Wu, Yibin Pu, Guanli Jiang, Jing Zhan, Yingmei Wang State Key Laboratory, cold and {1. regions environmental and engineering research institute, chinese academy of sciences, lanzhou 730000, Gansu, china State Key Laboratory Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 Gansu China

Gas hydrates formation and dissociation processes inside porous media are always accompanied by water transfer behavior, which is similar to the water behavior of ice freezing and thawing processes. These processes have been studied by many researchers, but all the studies are so far on the water transfer characteristics outside porous media and the water transfer characteristics inside porous media have been little known. In this study, in order to study the water transfer characteristics inside porous media during methane hydrate formation and dissociation processes, a novel apparatus with three pF-meter sensors which can detect water content changes inside porous media was applied. It was experimentally observed that methane hydrate formation processes were accompanied by water transfer from bottom to top inside porous media, however, the water behavior during hydrate dissociation processes was abnormal, for which more studies are needed to find out the real reason in our future work.

关键词： methane hydrate formation and dissociation processes: water transfer inside porous media saturated

^(1.7)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 research 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 research institute, chinese academy of sciences, lanzhou 730000, china china Certer of Desert {1. 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 {1. 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 1.7Cs deposition by wind and water in the Dalian Lake of Gonghe Basin, Qinghai Province are defined. The vertical profile of 1.7Cs in the lacustrine sediments exhibits three 1.7Cs activity maxima and one minimum. The major maximum corresponds to the global I37Cs fallout in 1.63; the two secondary maxima correspond to the leakage of the Chernobyl reactor in 1.86 and complete desiccation of the lake in 1.94, respectively. The minimum corresponds to aeolian deposition caused by extensive reclamation in the late 1.80s and early 1.90s. The 1.7Cs data set was used to evaluate average sedimentation rate of the Dalian Lake since 1.63. The deposition was stable in 1.63-1.86 and 1.94-1.98, and it was rapid during 1.86?994. This preliminary study reveals that l37Cs has the same potential to trace environmental changes introduce by human interference in {1./semi{1. regions as in humid regions.

关键词： 1.7Cs technique Dalian Lake sedimentation rate.

LANDSCAPE ECOLOGICAL CONSTRUCTION IN RURAL china:THEORY AND APPLICATION

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chinese Geographical Science 2001年第2期11卷 104-114页

作者： XIAO Du-ning (cold and {1. regions environmental and engineering research institute, the chinese academy of sciences, lanzhou 730000, P.R.china institute of Applied Ecology,the chinese academy of sciences, Shenyang 1.001.,P.R.china ) cold and {1. regions environmental and engineering research institute the Chinese Academy of Sciences Lanzhou P.R. China institute of Applied Ecology the Chinese Academy of Sciences Shenyang P. R. China

In landscape with overpopulation, intensive management for economic production, and where even small natural-vegetation patches are scarce, ecological conservation generally must be developed in the course of economic development. Thus “landscape ecological construction” has evolved in china. This approach adds spatial elements and alters landscape pattern to strengthen inter-ecosystem linkages, improve functioning of damaged ecosystems, and increase productivity and stability of the whole landscape. Five examples of managed landscapes in china are presented: dike-pond systems in a river delta; multi-pond system in a rice paddy landscape; field-grass-wood grid system on unstable sand dunes; shelterbelt network in a crop field area; and field-grass-wood mosaic system on highly erodible hilly farmland. These indicate that ecological conditions can be improved along with increased economic production. Altering landscape structure and ecological flows by introducing small landscape elements in distinct spatial patterns is considered a key to the results. This reshaping of the land has focused on changing patch size, regularity of arrangement, biological and hydrological corridors, and networks, the matrix and grain size. It suggests that such changes can increase negative feedbacks and increase stability. Finally, planning and design principles are pinpointed for the landscape ecological construction process.

关键词： landscape planning ecological construction rural china

Recent glacial retreat in High Asia in china and its impact on water resource in Northwest china

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Science china Earth {1. 2004年第12期47卷 1065-1075页

作者： YAO Tandong 1,2 ,WANG Youqing 2 ,LIU Shiying 2,1 ,PU Jianchen 2,1 ,SHEN Yongping 2 & LU Anxin 2,1 1.institute of Tibetan Plateau research,chinese academy of sciences,Beijing 100029,china 2.cold and arid regions environmental and engineering research institute,chinese academy of sciences,lanzhou 730000,china chinese {1. of sciences Institute of Tibetan Plateau Research Beijing China chinese {1. of sciences Cold and Arid Regions Environmental and Engineering Research Institute Lanzhou China

Under the impact of climatic warming, the glaciers in the High Asia in china have been retreating continuously with negative glacial mass balance in recent several decades. The retreat became more intensive in the past 1. years. The spatial pattern of the glacial retreat in the High Asia in china is that the smallest magnitude of retreat is in the inland of the Tibetan Plateau, the magnitude increases from the inland to the margin of the Tibetan Plateau, and the largest magnitude at the margin of the Tibetan Plateau. The glacial retreat in the High Asia in china has an important impact on the water resource of the arid regions in Northwest china. This study shows that the glacial retreat in the 1.90s has caused an increase of 5.5% in river runoff in Northwest china. In the Tarim River basin, the increase of river runoff is higher than 5.5%.

关键词： High Asia, glacial fluctuation, impact on water resource.

Stochastic modelling of soil moisture dynamics in a grassland of Qilian Mountain at point scale

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Science china Earth {1. 2007年第12期50卷 1844-1856页

作者： LIU Hu,ZHAO WenZhi HE ZhiBin & ZHANG LiJie Linze Inland River Basin research Station,chinese Ecosystem research Network Laboratory of Watershed Hydrology and Ecol-ogy,cold and arid regions environmental and engineering research institute,chinese academy of sciences,lanzhou 730000,china Linze Inland River Basin research Station Chinese Ecosystem Research Network China Laboratory of Watershed Hydrology and Ecology Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China

Stochastic modeling of soil moisture dynamics is crucial to the quantitative understanding of plant responses to water stresses,hydrological control of nutrient cycling processes,water competition among plants,and some other ecological dynamics,and thus has become a hotspot in ecohydrology at *** this paper,we based on the continuously monitored data of soil moisture during 2002―2005 and daily precipitation date of 1.92―2006,and tried to make a probabilistic analysis of soil moisture dynamics at point scale in a grassland of Qilian Mountain by integrating the stochastic model improved by Laio and the Monte Carlo *** results show that the inter-annual variations for the soil moisture patterns at different depths are very significant,and that the coefficient of variance(CV) of surface soil moisture(20 cm) is almost continually kept at about 0.23 whether in the rich or poor rainy ***,it has been found that the maximal CV of soil moisture has not always appeared at the surface *** of the analytically derived soil moisture probability density function(PDF) with the statistical distribution of the observed soil moisture data suggests that the stochastic model can reasonably describe and predict the soil moisture dynamics of the grassland in Qilian Mountain at point *** extracting the statistical information of the historical precipitation data in 1.94―2006,and inputting them into the stochastic model,we analytically derived the long-term soil moisture PDF without considering the inter-annual climate fluctuations,and then numerically derived the one when considering the inter-annual fluctuation effects in combination with a Monte-Carlo *** was found that,though the peak position of the probability density distribution significantly moved towards drought when considering the disturbance forces,and its width was narrowed,accordingly its peak value was increased,no significant bimodality was observed in the soil moistur

关键词： soil moisture dynamics, stochastic modelling, Monte Carlo method, probability density function, grassland ecosystem

Vertical quantitative and dominant population distribution of the bacteria isolated from the Muztagata ice core

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Science china Earth {1. 2005年第10期48卷 1728-1739页

作者： XIANG Shurong1, YAO Tandong1, 2, AN Lizhe1, 3, WU Guangjian2, XU Baiqing2, MA Xiaojun 3, LI Zhen1, WANG Junxia1 & YU Wusheng1 1. Key Laboratory of Ice Core and cold regions Environment, cold and arid regions environmental and engineering research institute, chinese academy of sciences, lanzhou 730000, china 2. institute of Tibetan Plateau research, chinese academy of sciences, Beijing 100085, china 3. College of Life Science, lanzhou University, lanzhou 730000, china chinese {1. of sciences lanzhou University

Vertical distribution of the main bacteria isolated from the Muztagata ice core (about 22.4 m) was investigated by means of cultivation and 1.S rRNA sequence analysis. The results showed that the amount of culturable bacteria fluctuated with ice core depth, and was more in dirty layer than in clean ice, which suggested the close corresponding relationship between high input of the bacteria deposited by wind and snowflow and dirty layer. Most of the bacteria were psychrophiles and psychrotolerants, including α- and γ-proteobacteria, Cryobacterium psychro-philum, CFB (Cytophaga-Flavobacterium-Bacteroides) group, high-G+C gram-positive bacteria (HGC). Acinetobacter sp. and HGC repeatly occurred in different ice depths, and their quantita-tive distribution was consistent with the change of the total amount of culturable bacteria with depth, which suggested the main bio-indicator; while Flavobacterium, Cryobacterium psychro-philum, and α-proteobacteria, also functioned as a secondary indicator of climatic and environ-mental changes. This study is the first report concerning continuous quantitative variation and pattern of the main culturable bacteria in ice core section.

关键词： Pamirs Plateau, ice core, pattern of bacteria, bio-indicator.

Vicissitude of Sogo Nur and environmental-climatic change during last 1.00 years

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Science china Earth {1. 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 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 {1. 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.