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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,{2. of mountain hazards and environment, The chinese academy of sciences,chengdu 610041,china [a]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%,2.%, 36%,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

Prediction of Debris-flow Danger Area by Combining Hydrological and Inundation Simulation Methods

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Journal of mountain Science 2011年第1期8卷 1-9页

作者： CUI Peng Key Laboratory of mountain hazards and Earth Surface Process Chinese Academy of Sciences Chengdu 610041 China institute of mountain {2. and environment Chinese Academy of Sciences Chengdu 610041 China Graduate School of chinese academy of sciences Beijing 100049 China

Debris flows have caused serious human casualties and economic losses in the regions strongly affected by the Ms8.0 Wenchuan earthquake of 2.o8. Debris flow mitigation and risk assessment is a key issue for reconstruction. The existing methods of inundation simulation are based on historical disasters and have no power of prediction. The rain- flood method can not yield detailed flow hydrograph and does not meet the need of inundation simulation. In this paper, the process of water flow was studied by using the Arc-SCS model combined with hydraulic method, and then the debris flow runoff process was calculated using the empirical formula combining the result from Arc-SCS. The peak discharge and runoff duration served as input of inundation simulation. Then, the dangerous area is predicted using kinematic wave method and Manning equation. Taking the debris flow in Huashiban gully in Beichuan County, sichuan Province, china on 2. Sep. 2.o8 as example, the peak discharge of water flow and debris flow were calculated as 35.52.m3·s-1 and 2.5.66 m3·s-, with error of 4.15% compared to the measured values. The simulated area of debris-flow deposition was 161,500 m2. vs. the measured area of 144,097 m2. in error of 81.75%. The simulated maximum depth was 12.3 m, consistent with the real maximum depth between lO and 15 m according to the field survey. The minor error is mainly due to the flow impact on buildings and variations in cross-section configuration. The present methodology can be applied to predict debrisflow magnitude and evaluate its risk in other watersheds inthe earthquake area.

关键词： Debris flow Arc-SCS model Inundation simulation Risk analysis Wenchuan earthquake

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 {2. and environment, 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.

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 {2. and environment, 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.

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

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Science china Earth sciences 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 {2. 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 1. institute of mountain {2. and environment Chinese Academy of Sciences Chengdu 610041 China 3. Resource and environment School Lanzhou University Lanzhou 730000 China 2. Cold and Arid Regions environmental and Engineering Research institute Chinese Academy of Sciences Lanzhou 730000 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 2..11% under the permafrost environment degradation during recent 15 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.

Optimized design model for sediment-trapped dam by GIS techniques

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Science china(Technological sciences) 2003年第z1期46卷 175-187页

作者： LI Fabin, TU Jianjun & HU Kaiheng institute of mountain {2. and environment, 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 sediment-trapped dam (STD) is one of the major engineering measures in preventing debris flow, while the design of such an STD has been proven as the most complicated systematic engineering. Supported by geographical information system (GIS)method and techniques, this paper presents an optimized STD design model which is built through calculating STD height and reservoir capacity, designing cross section,analyzing load capacity and structural stability. Guided by a principle of taking both the stability of STD as the constraint condition and the optimized design as a nonlinear programming, this model makes it possible for a precise calculation of the STD volume and its reservoir capacity, aiming at getting the minimum ratio between project investment and reservoir capacity. This model preliminarily achieves the optimized designing of important parameters of STD involving in STD volume (project investment), dam stability and reservoir capacity (sediments trapped by STD), and also provides a new solution attempting for the optimized design of project in preventing debris flow.

关键词： debris flow, sediment-trapped dam, geographical information system, optimized design, model.

Monitoring on soil erosion and sediment delivery at a typical basin of the middle and lower reaches of the Jialing River by remote sensing

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中国科学：技术科学英文版 2003年第z1期46卷 148-155页

作者： FAN Jianrong, ZHONG Xianghao & LIU Shuzhen institute of mountain {2. and environment, 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 monitoring work was performed on soil erosion in Lizixi drainage area respectively in 1986 and 1999 by multiple methods with the information extracted from the Landsat TM imagery and Spot imagery. The variation of erosion quantity in this area is calculated based on the monitoring result of the erosion intensity and area in these two years. The change of sediment delivery is also analyzed. The research result shows that compared to 1986, in 1999, the erosion area reduced, especially for the area of moderate intensity and above, and the intensity and quantity of erosion decreased. Compared to this period from 1965 to 1986, the sediment delivery ratio has been changed from 0.2. to 0.11 after 1986. The research result could help the decision-making for further water and soil conversation work in Lizixi drainage area, and it also offers reference for monitoring,evaluating and predicting soil erosion in other drainage areas.

关键词： drainage area, soil erosion, remote sensing, sediment delivery.

Debris Flow Hazard Assessment Based on Support Vector Machine

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Wuhan University Journal of Natural sciences 2006年第4期11卷 897-900页

作者： YUAN Lifeng 1, 2., ZHANG Youshui 3 1. institute of mountain {2. and environment, chinese academy of sciences, chengdu 610041, sichuan, china 2. Graduate University of chinese academy of sciences, Beijing 100049, china 3. institute of Geographical sciences and Natural Resources Research, chinese academy of sciences, Beijing 100101, china institute of mountain {2. environment Chinese Academy of Sciences 610041 Chengdu Sichuan China Graduate University of chinese academy of sciences 100049 Beijing China institute of Geographical sciences Natural Resources Research Chinese Academy of Sciences 100101 Beijing China

Seven factors, including the maximum volume of once flow , occurrence frequency of debris flow , watershed area , main channel length , watershed relative height difference , valley incision density and the length ratio of sediment supplement are chosen as evaluation factors of debris flow hazard degree. Using support vector machine （SVM） theory, we selected 2.9 basic data of 37 debris flow channels in Yunnan Province as learning samples in this study. We create a debris flow hazard assessment model based on SVM. The model was validated though instance applications and showed encouraging results.

关键词： debris flow hazard assessment support vector machine (SVM)

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

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Science china Earth sciences 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 {2. 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 1. institute of mountain {2. and environment Chinese Academy of Sciences Chengdu 610041 China 3. Resource and environment School Lanzhou University Lanzhou 730000 China 2. Cold and Arid Regions environmental and Engineering Research institute Chinese Academy of Sciences Lanzhou 730000 China

Since the 1960s, 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 china. 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 china, 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 1965. 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 1967, has resulted in a mean annual runoff decrease of 2..12., 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 2..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.

Validation of three infiltration models on purple soil under simulated rainfall

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Progress in Natural Science:Materials International 2007年第9期17卷 1059-1066页

作者： Wang Yukuan1,2.Fu Bin1,3,Xu Pei1,2.Wang Daojie1,2.Wang Xiantuo1,3 and Wang Yongqiang1,3(1.Key Laboratory of mountain Surface Process and hazards,{2. academy of Seiences,chengdu 610041,china 2.institute of mountain hazards and environment,{2. academy of sciences,chengdu 610041,china 3.Graduate University of the chinese academy of sciences,Beijing 100049,china) Key Laboratory of mountain Surface Process and hazards Chinese Academy of Seiences Chengdu 610041 China institute of mountain {2. and environment， chinese academy of sciences， chengdu 610041 China Graduate University of the chinese academy of sciences Beijing 100049 China

So as to find models suitable for the prediction of water infiltration in purple soil,infiltration rates simulated by three popular empirical infiltration models,Horton model,Kostiakov model,and the modified Kostiakov model,were compared by using those observed results on slope in purple soil under rainfall simulation.2. sets of infiltration data were divided into two parts for parameter estimation and validation *** performance of the three infiltration models was evaluated with the Nash and Sutcliffe efficiency *** results show that the percent for Nash and Sutcliffe efficiency greater than 0.7 is about 69.7% for the Horton model,and 48.48%,and 54.55% for the Kostiakov model and the modified Kostiakov model,*** model is better than Kostiakov model and the modified Kostiakov model in most rain events in the ***,Kostiakov model is still suitable for reasonable prediction of the infiltration in purple soil sloping farmland because fewer parameters are ***,rainfall intensity has significant effects on the parameter values used in the simulation *** simulation results can be improved by choosing suitable parameters according to the rainfall intensity.

关键词： infiltration model sloping farmland purple soil rainfall simulation