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Wuhan University Journal of Natural sciences 2008年第3期13卷 331-335页

作者： YAN Yan WANG Xiaodan institute of mountain hazards and {3. ChineseAcademy of Sciences Chengdu 610041 Sichuan China

Distribution characteristics of soil organic matter（sOM） and total nitrogen（TN） were studied in different plant communities of the Yajiageng vertical belt in Gongga mountain around the Dadu River banks. The results show：（1） the contents of sOM and TN of the plant communities gradually decreased with the following order： subalpine coniferous forest （3.027 m）, subalpine meadow （3.873.m）, coniferous broadleaved mixed forest（2 73. m）, subalpine shrub（3.565 m） and treeline（3.564 m）. （2） With soil profile depth increasing, the contents of sOM and TN gradually decreased. For different vegetation types, the contents of sOM and TN in sub-alpine coniferous forest were higher than that of other vegetational types. （3.The ratio of the content of carbon to the content of total nitrogen （Cc/CTN）Was 13.5-27.6, which was relatively lower than the appropriate Cc/CTN of 25-3., and indicated that the soil in favor of the organic matter decomposed and nutrients released. Cc/CTN in the soil had no correlation with sea level altitude. However, its distribution in the soil x, aried with different vegetation types. （4） Nitrogen in sOM existed mainly in the form of organic nitrogen, and Cc/CTN in the soil was not obvious correlated with sOM and TN.

关键词： Gongga mountain soil organic matter(sOM) total nitrogen(TN) vertical belt

Response of Biomass spatial Pattern of Alpine Vegetation to Climate Change in Permafrost Region of the Qinghai-Tibet Plateau,china

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Journal of mountain science 2010年第4期7卷 301-314页

作者： ZHANG Yu WANG Genxu WANG Yibo College of Resources & environment Lanzhou UniversityLanzhou 730000China institute of mountain hazards and {3. Chinese Academy of SciencesChengdu 610041China

Alpine ecosystems in permafrost region are extremely sensitive to climate *** determine spatial pattern variations in alpine meadow and alpine steppe biomass dynamics in the permafrost region of the Qinghai-Tibet Plateau,china,calibrated with historical datasets of above-ground biomass production within the permafrost region's two main ecosystems,an ecosystem-biomass model was developed by employing empirical spatialdistribution models of the study region's precipitation,air temperature and soil *** model was then successfully used to simulate the spatio-temporal variations in annual alpine ecosystem biomass production under climate *** a 0.44°C decade-1 rise in air temperature,the model predicted that the biomasses of alpine meadow and alpine steppe remained roughly the same if annual precipitation increased by 8 mm per decade-1,but the biomasses were decreased by 2.7% and 2.4%,respectively if precipitation was *** a 2.2°C decade-1 rise in air temperature coupled with a 12 mm decade-1 rise in precipitation,the model predicted that the biomass of alpine meadow was unchanged or slightly increased,while that of alpine steppe was increased by 5.2%.However,in the absence of any rise in precipitation,the model predicted 6.8% and 4.6% declines in alpine meadow and alpine steppe biomasses,*** response of alpine steppe biomass to the rising air temperatures and precipitation was significantly lesser and greater,respectively than that of alpine meadow biomass.A better understanding of the difference in alpine ecosystem biomass production under climate change is greatly significant with respect to the influence of climate change on the carbon and water cycles in the permafrost regions of the Qinghai-Tibet Plateau.

关键词： Permafrost change Qinghai-TibetanPlateau Alpine ecosystem Grassland biomass Climate change Response model

Measuring the Internal Velocity of Debris Flows Using Impact Pressure Detecting in the Flume Experiment

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Journal of mountain science 2011年第2期8卷 109-116页

作者： YANG Hongjuan WEI Fangqiang HU Kaiheng sergey CHERNOMORETs HONG Yong LI Xiaoyu XIE Tao Key Laboratory of mountain hazards and surface Process ChineseAcademy of Sciences Chengdu 610041 China institute of mountain hazards and {3. Chinese Academy of Sciences Chengdu 610041 China Faculty of Geography Moscow State University Moscow Russia

Measuring the internal velocity of debris flows is very important for debris flow dynamics research and designing debris flow control works. However, there is no appropriate method for measuring the internal velocity because of the destructive power of debris flow process. In this paper, we address this problem by using the relationship between velocity and kinetic pressure, as described by surface velocity and surface kinetic pressure data. Kinetic pressure is the difference of impact pressure and static pressure. The former is detected by force sensors installed in the flow direction at the sampling section. Observations show that static pressure can be computed using the formula for static water pressure by simply substituting water density for debris flow density. We describe the relationship between surface velocity and surface kinetic pressure using data from seven laboratory flume experiments. It is consistent with the relationship for single phase flow, which is the measurement principle of the Pitot tube.

关键词： Internal velocity Measurement Debris flow Impact pressure

Discrete Element Modeling of Debris Avalanche Impact on Retaining Walls

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Journal of mountain science 2010年第3期7卷 276-281页

作者： LI Xinpo HE siming LUO Yu WU Yong Key laboratory of mountain hazards and Earth surface Process CAS Chengdu 610041 China institute of mountain hazards and {3. CAS Chengdu 610041 China

In china,gravity retaining walls are widely used as protection structures against rockfalls,debris flows and debris avalanches along the roads in mountainous *** this paper,the Discrete Element Method(DEM) has been used to investigate the impact of granular avalanches and debris flows on retaining *** debris is modeled as two dimensional circular disks that interact through frictional sliding *** basic equations that control the deformation and motion of the particles are introduced.A series of numerical experiments were conducted on an idealized debris slide impacting a retaining *** parametric study has been performed to examine the influences of slope geometry,travel distance of the sliding mass,wall position,and surface friction on the impact force exerted on the *** show that:1) the force achieves its maximum value when slope angle is equal to 60°,as it varies from 3.° to 75°;2) an approximate linear relationship between the impact force and the storage area length is determined.

关键词： Debris flow debris avalanche rockfallretaining wall Discrete Element Method

sTRATEGIEs AND POLICIEs ON THE IMPLEMENTATION OF DEVELOPMENT OF THE WEsTERN AREA OF china

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Natural Disaster Reduction in china 2002年第1期 9-14页

作者： Zhong Xianghao (chengdu institute of mountain {3. and environment, chinese academy of sciences & Ministry of Water Resoures, PRC, chengdu 61004., china)

NEW sTRATEGIEs FOR AGRICULTURAL DEVELOPMENT IN china's mountain AREAs

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Natural Disaster Reduction in china 2002年第3期 36-41页

作者： Chen Guojie (chengdu institute of mountain {3. and environment, chinese academy of sciences & the Ministry of Water Conservancy, chengdu 61004., sichuan, china)

Now that the problems of food and clothing have been solved substantially in the mountain areas of china, new strategies are needed for developing the agriculture in these areas, such as "farming according to market demands", "minimizing time distance between demand and supply", "enlarging the scale of farming", "raising the quality of produces", "industrializing agriculture", "developing eco agriculture", "providing farmer oriented training", "pursuing integrated mountain development", and so on.

关键词： agriculture development strategy industrialization of agriculture buyer’s market

GIs-based risk analysis of debris flow:an application in sichuan, southwest china

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International Journal of sediment Research 2008年第2期23卷 138-148页

作者： B.F.DI1,2,3.N.s.CHEN1,P.CUI1,Z.L.LI1,Y.P.HE4,and Y.C.GAO1 3.1 Ph.D.,chengdu institute of mountain {3. and environment,CAs,chengdu 61004.,china,Department of Architecture & environment,sichuan University,chengdu 610065,china,Graduate University of chinese academy of sciences,Beijing 100049,china,2 Prof.,Department of Architecture & environment,sichuan University,chengdu 610065,china,3.Graduate University of chinese academy of sciences,Beijing 100049,china 4 Department of Civil and environmental Engineering,san Diego state University,5500 Campanile Dr.san Diego,CA 92121,UsA [a]Ph.D. chengdu institute of mountain {3. and environment CAs chengdu 61004. china Department of Architecture & environment sichuan University chengdu 610065 china Graduate University of chinese academy of sciences Beijing 100049 china [b]Prof. Department of Architecture & environment sichuan University chengdu 610065 china [c]Graduate University of chinese academy of sciences Beijing 100049 china [d]Department of Civil and environmental Engineering san Diego state University 5500 Campanile Dr. san Diego CA 92121 UsA

Debris flow is a serious geologic hazard in *** is estimated that nationally debris flows cause up to 2 billion RMB(250 million Us$) in damages and 3.0-600 deaths and injuries *** mitigate debris flow hazards,it is necessary to map,model,and identify zones of debris flow hazards and vulnerability as to inform the local people about the potential risk with a geographic information *** research presents a regional scale case study modeling debris flow risk(hazard and vulnerability) in sichuan Province,southwestern *** this area,3.290 debris flows have been identified and the spatial-temporal distribution and activity characteristics of them have been *** on the available meteorological data,a Digital Elevation Model with the rate of 1:250,000 and a regional geological map,the 24-hr rainfall threshold(y) for debris flow occurrence is closely related(significant at 99% confidence level) to the index(x) defined using a geology factor(rock hardness:a) and a topographical factor(channel gradient:d) where y = 21 + 10200 / x,in which x = 2.7 × ea + 1000 × *** discipline is constructive in developing the rainfall threshold for debris flow activity in remote mountainous areas that lack *** a given watershed,a four-level debris flow hazard map is developed by comparing the rainfall threshold to the design rainfall intensities with 50-,20-,and 5-year average recurrence intervals,*** degree of debris flow vulnerability is determined by the watershed socio-economic conditions.A four-class debris flow risk map,at the final phase of the research,is generated by combining debris flow hazards and *** the debris flow risk assessment,the sichuan Province is classified into the slight,moderate,severe and very severe regions,which accounts for 3.%,19%,20% and 25% of total area respectively.

关键词： Debris flow Geographic information system Hazard Vulnerability Risk Rainfall threshold

A study on water film in saturated sand

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International Journal of sediment Research 2010年第3期25卷 221-232页

作者： LU X. B.1 and CUI P.2 1 Dr., Laboratory for Hydraulic and Ocean Engineering, institute of Mechanics, chinese academy of sciences, Beijing 100190,{3., 2 Prof., Key Laboratory for mountain Hazard and Earth surface Process, institute of mountain Hazard and environment, chinese academy of sciences, chengdu 61004.,{3., [a] Dr. Laboratory for Hydraulic Ocean Engineering Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China [b] Prof. Key Laboratory for Mountain Hazard Earth surface Process Institute of Mountain Hazard environment Chinese Academy of Sciences Chengdu 610041 China

Water film can serve as a sliding surface and cause landslides on gentle slopes. The development of "water film" in saturated sand is analyzed numerically and theoretically based on a quasi-three-phase model. It is shown that stable water films initiate and grow if the choking state (where the fluid velocity decreases to near zero) remains steady in a liquefied sand column. Discontinuity can occur in pore water velocity, grain velocity and pore pressure after the initiation of a water film. However, the discontinuity and water film can disappear once the choking state is changed. The key to the formation of water film is the choking in the sand column caused by eroded fine grains.

关键词： saturated sand Water film Liquefaction

Mapping the Farming-pastoral Ecotones in china

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Journal of mountain science 2009年第1期6卷 78-87页

作者： ZHANG Jian WEI Jie CHEN Quangon institute of mountain hazards and {3. Chinese Academy of Sciences Chengdu 610041 China Tourism College Chongqing Normal University Chongqing 400047 China school of PastoralAgricultural science and Technology Lanzhou University Lanzhou 730020 China Graduate University of the chinese academy of sciences Beijing 100049 China

Conventional farming-pastoral ecotones methods of delineating were not quantitative and could not fully show their spatial distribution. The present paper attempts to develop quantitative methods for mapping farming-pastoral ecotones in china. Nine indicators, related to temperature, precipitation and altitude aspects, were selected to quantify ecological susceptibility of vegetation （crops and forage）. Methods of analytic hierarchy process （AHP） and expert score ranking combined with fuzzy set theory were applied to assign the weight for each indicator and to define the membership functions. The geographic information system （GIs） was used to manage the spatial database and conduct the spatial analysis. According to the spatial calculation of evaluation model integrated with GIs, the ecological susceptibility of vegetation （crops and forage） was mapped. Three different zones, pastoral area, farming-pastoral ecotones and farming area, were classified by spatial cluster analysis and the maximum likelihood classification for the numeric map of vegetation ecological susceptibility by GIs. This map was validated by the economic statistical result based on the ratio of the output value from animal husbandry in total output value of agriculture by the National Bureau of statistics in china, indicating that the mapping of the farming-pastoral ecotones may be accepted.

关键词： AHP Farming-pastoral ecotone Fuzzyset theory GIs

UNCERTAINTY ANALYsIs ON ZONATION MAPs OF DEBRIsFLOW HAZARD IN YUNNAN PROVINCE,china

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chinese Geographical science 2000年第2期10卷 138-143页

作者： LIU Xi-lin(Dapartment of Urban and environmental scicnces, Peking University Beijing 100871, P.R.china institute of Moun tain {3. and environment, the chinese academy of sicnces, chengdu 61004.,P.R.china) Department of Urban and environmental sciences Peking University Beijing P. R. China institute of mountain hazards and {3. the Chinese Academy of Sciences Chengdu P. R. China

Different researchers select different factors and use different methods to assess the regional hazard degrees of debris now. consequenily, even for the same region, tb.. are often different hazard zonation maps, and there must be some uncertainty in the zonations. Thus the ceriainty analysis of zonation maps becomes obviously *** debris now hazard, those zonation maps with a certainty analysis could provide most valuable information for land users, hazard managers and policy makers. By comparison of three researchers’ findings in Yunnan Province, this paPer shows that seven to nine iafluential factors are chosen for the zonation maps. spatial density of debris flow ravines,regional average rock-weathering coefficient, yearly precipitation, days of≥50 mm daily rainfall, and proportion of sloping land with slope≥25℃to the total land are the most acceptable factors. Mathemahcal methods of maximum-minimumvalues, upperlower limit values and Fuzzy values are used to quantify the factors. step-by-step methodoogy is commonly used for the zonation maps. Research results show that mchmum uncedrinty is 66. 6% and minimum uncertainty is 3..7% in debris now hazard maps of zhaotong Prefecture and Yunnan Province. Therefore there is still much work for us to improve the zonation methedology.

关键词： debris flow hazard zonation uncertainty zonation map