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

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. {3. of Desert Research, chinese academy of sciences, Lanzhou 73.000, 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 {3. 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.

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GIS-based Earthquake-Triggered Landslide Hazard Zoning Using Contributing Weight Model

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Journal of mountain Science 2010年第4期7卷 339-352页

作者： WANG Meng institute of mountain hazards and {3. ChineseAcademy of Science Chengdu 610041 China Graduate University of chineseacademy of sciences Belling 100049 China Key Laboratory of Geo-surface Process and mountain hazards Institute of Mountain Hazards and Environment Chinese Academy of Science Chengdu 610041 China

Earthquake-triggered landslides have aroused widespread attention because of their tremendous ability to harm people's lives and *** best way to avoid and mitigate their damage is to develop landslide hazard maps and make them available to the public in advance of an *** construction can then be built according to the level of hazard and existing structures can be retrofit as *** recent years various approaches have been made to develop landslide hazard maps using statistical analysis or physical ***,these methods have *** study introduces a new GIS-based approach,using the contributing weight model,to evaluate the hazard of seismically-induced *** this study,the city and surrounding area of Dujiangyan was selected as the research area because of its moderate-high seismic *** parameters incorporated into the model that related to the probability of landslide occurrence were:slope gradient,slope aspect,geomorphology,lithology,base level,surface roughness,earthquake intensity,fault proximity,drainage proximity,and road *** parameters were converted into raster data format with a resolution of 25×25m2 *** of the GIS correlations shows that the highest earthquake-induced landslide hazard areas are mainly in the hills and in some of the moderately steep mountainous areas of central *** highest hazard zone covers an area of 11.1% of the study area,and the density distribution of seismically-induced landslides was 3.025/km2 from the 2008 Wenchuan *** moderately hazardous areas are mainly distributed within the moderately steep mountainous regions of the northern and southeastern parts of the study area and the hills of the northeastern part;covering 3..0% of the study area and with a density distribution of 2.123.km2 resulting from the Wenchuan *** lowest hazard areas are mainly distributed in the topographically flat plain in the northeas

关键词：危险性区划山体滑坡地震活动物理模型权重引发 GIS 地理信息系统

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Risk and size estimation of debris flow caused by storm rainfall in mountain regions

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Science china(Technological sciences) 2003年第Z1期46卷 12-19页

作者： CHENG Genwei institute of mountain hazards and {3., chinese academy of sciences and Ministry of Water Resources, chengdu 610041, china chinese Acad Sci Inst Mt Hazards & Environm Chengdu 610041 Peoples R China Minist Water Resources Chengdu 610041 Peoples R China

Debris flow is a common disaster in mountain regions. The valley slope, storm rainfall and amassed sand-rock materials in a watershed may influence the types of debris flow. The bursting of debris flow is not a pure random event. Field investigations show the periodicity of its burst, but no directive evidence has been found yet. A risk definition of debris flow is proposed here based upon the accumulation and the starting conditions of loose material in channel. According to this definition, the risk of debris flow is of quasi-periodicity. A formula of risk estimation is derived. Analysis of relative factors reveals the relationship between frequency and size of debris flow. For a debris flow creek, the longer the time interval between two occurrences of debris flows is, the bigger the bursting event will be.

关键词： debris flow, periodicity, estimating method.

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GULLY-SPECIFIC DEBRIS FLOW HAZARD ASSESSMENT IN china

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chinese Geographical Science 2003年第2期13卷 112-118页

作者： LIU Xi-lin (institute of mountain hazards and {3., chinese academy of sciences, C hengdu 610041, P.R. china) institute of mountain hazards and {3. Chinese Academy of Sciences Chengdu P. R. China

Techniques of gully-specific debris flow hazard assessment develope d in four periods since the end of the 1980s have been discussed in the present paper. The improvement for the empirical assessment method is the sectionalized function transformation for the factor value, rather than the classified logical transformation. The theoretical equation of the gully-specific debris flow haz ard is expressed as the definite integral of an exponential function and its num erical solution is expressed by the Poisson Limit Equation. Current methods for assessment of debris flow hazard in china are still valid and practical. The fur ther work should be put on the study of the reliability (or uncertainty) of the techniques. For the future, we should give a high priority to the relationship b etween debris flow magnitude and its frequency of occurrence, make more developm ents of prediction model on debris flow magnitude, so as to finally reach the go al of assessing the hazard of debris flow by theoretical model, and realize both actuality assessment and prediction appraisal of debris flow.

关键词：泥石流危害工程地质理论公式预测

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Human activity response and prevention strategies on soil and water loss in Sichuan Province

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Science china(Technological sciences) 2003年第Z1期46卷 91-109页

作者： FANG Yiping & CHEN Guojie institute of mountain hazards and {3., chinese academy of sciences and Ministry of Water Resources, chengdu 610041, china chinese Acad Sci Inst Mt Hazards & Environm Chengdu 610041 Peoples R China Minist Water Resources Chengdu 610041 Peoples R China

Ten major factors have been selected to judge the degree of disturbance from human activity and the corresponding relationship of the impact on soil and water loss in Sichuan Province. Correlation analysis has demonstrated that stock-carrying capacity, percentage of land reclamation, population density, GDP per capita, mineral modulus and percentage of forest coverage are the 6 most relevant human activity factors. The analysis on the degree of disturbance has shown that population pressure, excessive or unreasonable activities in development of resources and destructive behavior of humans are the main causes of soil and water loss. Consequently, solving the various problems in the negative activity of humans and regulating human behavior are the first tasks that should be tackled in the conservation of water and soil. In the new era, the prevention and rectification of soil and water loss are measures based on the foundation of the ecosystem, which is a kind of management strategy for sustainable development. The foundation of this method is made up of the system innovations and breakthroughs in terms of aims, philosophy, measures, and aspects of the prevention and rectification of soil and water loss, simultaneous advance from the conceptual, policy, spatial, technical and mode levels and system integration on the treatment strategies.

关键词： Sichuan, degree of disturbance, soil and water loss, system innovation.

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Changes in overland flow and sediment during simulated rainfall events on cropland in hilly areas of the Sichuan Basin,china

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Progress in Natural Science:Materials International 2009年第11期19卷 1613-1618页

作者： Bin Fu,Yukuan Wang~*,Pei Xu,Daojie Wang Key Laboratory of mountain hazards and Earth Surface Process,institute of mountain hazards and environment, The chinese academy of sciences,chengdu 610041,china Key Laboratory of mountain hazards and Earth Surface Process Institute of Mountain Hazards and Environment The Chinese Academy of Sciences Chengdu 610041 China

Water and soil loss are the major causes of the land degradation in the hilly area of the Sichuan Basin,china,where purple soil(FAO, Calcaric Regosols) is widely *** research has been conducted on changes in overland flow and sediment during rain events on sloping cropland in this *** this study,45 artificial rainfall events were applied to five runoff plots with slopes of 9%,18%,27%, 3.%,and 47%,*** showed that erosion processes on purple soil of sloping cropland are complex,because the sediment concentration changes with time under different *** to correlations between runoff discharge and sediment concentration, all erosion events were classified into three types:(1) positive correlation;(2) negative correlation;and(3. no *** correlations were dominant,accounting for 60%of all *** intensity,slope gradient,and tillage treatment were the main factors that influenced erosion events.

关键词： Discharge-sediment concentration relationships Water erosion Artificial rainfall Hilly area of the Sichuan Basin Purple soil

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Assessing the Carrying Capacity of Tourist Resorts: An Application of Tourists’ Spatial Behavior Simulator Based on GIS and Multi-Agent System

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Wuhan University Journal of Natural sciences 2005年第4期10卷 779-784页

作者： ZHANG Ren-jun 1,2 1. institute of mountain hazards and {3., chinese academy of sciences, chengdu 610041, Sichuan, china 2. Graduated School of the chinese academy of sciences, Beijing 10003., china institute of mountain hazards and {3. Chinese Academy of Sciences Chengdu Sichuan China Graduated School of the chinese academy of sciences Beijing China

Based on the study of visitors' individual spatial behaviors, a tourists'spatial behavior simulator (TSBS) to assess the carrying capacity of tourist resorts was developed,TSBS employs GIS (Geographic Information System) to manage the spatial data,and Multi-Agent systemto simulate the actions of individual visitors. By utilizing TSBS, visitors' travel patterns such aslocation, cost, and state can be analyzed and predicted. Based on this analysis and prediction, themodel of assessing the carrying capacity of resorts is built. Our results show that TSBS will be aneffective tool to accurately assess the carrying capacity of tourist resorts.

关键词： tourist resort carrying capacity TSBS GIS Multi-Agent simulator

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Effect of sediment on concentration of dissolved phosphorus in the Three Gorges Reservoir

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International Journal of Sediment Research 2011年第1期26卷 87-95页

作者： CAO Zhijing~1,ZHANG Xinbao~2,and AI Nanshan~3.institute of Architecture and environment,Sichuan University,chengdu 610065,{3., institute of mountain hazards and environment,chinese academy of sciences,chengdu 610041,{13., institute of Architecture and environment,Sichuan University,chengdu 610065,{3., Lecturer Institute of Architecture and Environment Sichuan University Chengdu 610065 China Prof. Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China Prof. Institute of Architecture and Environment Sichuan University Chengdu 610065 China

Eutrophication and algal bloom has been occurring in the Three Gorges Reservoir ever since the reservoir’s impoundment in *** concentration of dissolved phosphorus(DP) is one of the main controlling factors for algal *** sediment adsorbs DP thereby affecting the concentration of DP. The effect of the sediment reduction on the DP concentration of the Three Gorges Reservoir is discussed in this *** were taken from the Yangtze River and its tributaries,*** Minjiang River and the Tuojiang *** DP concentration of the water samples and the available phosphorus,total phosphorus,and phosphorus-fixing capacity of the sediment samples were *** amount of phosphorus adsorbed by the sediment was about 3.of the total DP load in the Yangtze *** experiment was done in the lab simulating the DP concentration,sediment concentration,and turbulence. The results showed that quite a high amount of DP was adsorbed by the *** adsorption capacity of the sediment was 13. mg/kg and the highest rate of adsorption was 29 mg/kg·*** Xiluodu Dam is located at nearly 1,100 km upstream of the Three Gorges *** Xiloudu Dam will trap sediment and thence reduce the sediment load entering the Three Gorges Reservoir after impoundment in *** is estimated that the sediment reduction due to the Xiluodu Dam may result in an increase of the DP concentration in the Three Gorges Reservoir by 6.8%.

关键词： Dissolved phosphorus Sediment load reduction Three Gorges Reservoir Adsorption capacity Eutrophication

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Study on mechanism of fiber grouted material in pre-stressed anchor rope

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中国科学：技术科学英文版 2003年第Z1期46卷 188-197页

作者： HE Siming, QIAO Jianping & WANG Chenghua institute of mountain hazards and {3., chinese academy of sciences and Ministry of Water Resources, chengdu 610041, china chinese Acad Sci Inst Mt Hazards & Environm Chengdu 610041 Peoples R China Minist Water Resources Chengdu 610041 Peoples R China

The fiber grouted material can reinforce the tension strength, shear strength as well as the index of fracture ductile, and remarkably improve the endurance of pre-stressed anchor rope under long-time loading. As a result, it has the better application foreground. Based on the shear log model and Hashin-Shtrikman upper and lower limited theorem, we have studied the mechanism of fiber grouted material applied in pre-stressed anchor rope and material property, and analyzed the effect of resistance strength of bond, resistance distribution of anchor section and the loading-deformation relationship of anchor body.

关键词： fiber grouted, pre-stressed anchor rope, shear log model, Hashin-Shtrikman upper-lower limited theorem.

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Behavior of pre-stress group anchors——Theory approach and model

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Science china(Technological sciences) 2003年第Z1期46卷 31-41页

作者： HE Siming, WANG Chenghua & QIAO Jianping institute of mountain hazards and {3., chinese academy of sciences and Ministry of Water Resources, chengdu 610041, china chinese Acad Sci Inst Mt Hazards & Environm Chengdu 610041 Peoples R China Minist Water Resources Chengdu 610041 Peoples R China

First of all the pre-stress group anchor ropes are resolved into two sub-systems: the stable rock stand lateral resistance load and inner bonding section stand lateral resistance load and pre-stress load. Then, discretization of every sub-system was carried on and it is assumed that different micro-sections possess uniform distribution side resistance. On the basis of Mindlin stress solution, stress overlay principle, modified layered-summation method as well as the load transfer method, we study the anchor group effect and present a theory model which calculates the anchor group effect and establishes the relevant iterate standard.

关键词： anchor group effect, Mindlin's stress solution, discretization, iterative solution.

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