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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 Environment 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 32.0% 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： Earthquake-triggered landslide GIS Contributing weight model Hazard zoning

Astronomical function and date of the Taosi observatory

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Science china(Physics,Mechanics & Astronomy) 2009年第1期52卷 151-158页

作者： WU JiaBi1, CHEN MeiDong2 & LIU CiYuan3 1 National Astronomical Observatories, chinese academy of sciences, Beijing 100012, china 2 Institute for the History of Natural Science, chinese academy of sciences, Beijing 100010, china 3 National Time Service Center, chinese academy of sciences, Xi’an 710600, china National Astronomical Observatories Chinese Academy of Sciences Beijing China Institute for the History of Natural Science Chinese Academy of Sciences Beijing China National Time Service Center Chinese Academy of Sciences Xi’an China

The Taosi site in Xiangfen County,Shanxi Province,may be the capital of the King Yao. Archeologists recently discovered a large semi-circular stamped-earth platform, II FJT1,which has a clear and definite pounded-earth central core together with a curved wall perforated by twelve gaps. The platform is said to be an ancient observatory used to determine the seasons by watching the sunrise. Each feature of II FJT1 was precisely measured and the data are reproduced in this paper. An astronomical analysis of slots E2 and E12 was carried out using the azimuths of the slots' centerlines and the vertical angle of the mountain ridge opposite, above which the sun rises. The results show that at present the sun is close to the two slots but does not exactly enter them at summer and winter solstice sunrise. Using 14C analysis archeologists dated the site to about 2100 BC. Because of the secular change in the obliquity of the ecliptic,at that date on the summer solstice the half-risen sun would have appeared inside slot E12 just to the right of the centerline,and on the winter solstice the sun would have been exactly on the centerline of slot E2. This result provides compelling proof that II FJT1 is an ancient observatory.

关键词： astro-archeology astro-chronology Taosi culture ancient observatory time service

Hedychium menghaiense (Zingiberaceae),a new species from Yunnan,china

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Journal of Systematics and Evolution 2010年第2期48卷 146-151页

作者： 1,2,3Xiu HU 1Nian LIU 1(Zhongkai University of Agriculture and Engineering,Guangzhou 510225,china) 2(South china Botanical Garden,chinese academy of sciences,Guangzhou 510650,china) 3(Graduate School of chinese academy of sciences,Beijing 100049,china) (Zhongkai University of Agriculture and Engineering Guangzhou 510225 China) (South china Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China) (Graduate School of chinese academy of sciences Beijing 100049 China)

Hedychium menghaiense *** & ***,a new species of the Zingiberaceae from Yunnan Province,china,is described and *** new species is currently known only from its type locality,Nannuoshan mountain,Menghai County,growing under evergreen broad-leaved forests at altitudes of 1400-1700 *** is similar to Hedychium forrestii Diels,but differs in its narrower and emarginate labellum folded inwards lengthwise,narrower staminodes,and scarlet *** recognition of the new species is supported by the results from analysis of sequence-related amplified polymorphism markers.

关键词： Hedychium Hedychium menghaiense X.Hu & N.Liu new species SRAP markers Zingiberaceae

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 Environment, chinese academy of sciences, C hengdu 610041, P.R. china) Institute of mountain Hazards and Environment 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： debris flow hazard gully-specific debris flow assessment theoreticalequation

On Post-Shear-Instability in Saturated Soils

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地学前缘 2009年第S1期16卷 262-263页

作者： Xiaobin Lu~1,Xuhui Zhang~2 1.Institute of Mechanics,chinese academy of sciences,Beijing 100080,china. 2.Institute of mountain Hazard and Environment,chinese academy of sciences,Chengdu china,

The study on the development of shear band is very import since it is the main reason of landslide. According to experimental results,there is only one shear band forming at last when the soil specimen beard shear loa... 详细信息

关键词： shear band landslide finite amplitude disturbances

Soil Evolution Features of Debris Flow Waste-Shoal Land

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Journal of mountain Science 2009年第2期6卷 181-188页

作者： CUI Peng GE Yonggang ZHUANG Jianqi WANG Daojie Key Laboratory of mountain Hazards and Land Surface Processes Chinese Academy of Sciences Chengdu 610041 China Institute of mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China Graduate University of chinese academy of sciences Beijing 100049 China

The reclamation and utilization of debris flow waste-shoal land plays an important role in the mitigation and control of debris flow hazards, which thus contributes a lot to the exploitation of insufficient land resources in mountainous areas and the reduction of losses caused by debris flow. The aim of this paper is to discuss the features and mechanism of soil evolution of debris flow waste-shoal land so as to search for the available modes of its reclamation and utilization. The Jiangjiagou Ravine, a typical debris flow ravine, was selected to study soil evolution features of debris flow waste-shoal land based on the analysis of soil physicochemical properties and soil microstructure. It was found that the soil evolution rates of debris flow waste-shoal land varied with different modes of reclamation. For the land which had been reclaimed for less than 10 years, soil evolved most rapidly in paddy fields, and more rapidly in dry farmland than in naturally restored waste-shoal land. For the land which had been used for more than 10 years, the soil evolution rates of dry farmland, naturally restored waste-shoal land and paddy farmland decreased in the file. For the same utilization period of time, significant differences were recognized in soil evolution features under different modes of reclamation. Analysis data showed that soil clay content, soil thickness, the psephicity of skeleton particles and contents of microaggregates (2 mm) in paddy farmland were all highest. Soil nutrients and porosity of dry farmland were better than those of paddy farmland and naturally restored waste-shoal land, and those of paddy farmland were superior to those of naturally restored waste-shoal land. Paddy farmland characterized by rapid pedogenesis, stable evolution and high utilizability was the priority candidate for the reclamation and utilization of debris flow waste-shoal land.

关键词： Debris flow waste-shoal land Reclamation mode Utilization time Soil properties Soil microstructure

On the Evolution of the Lower Energy Cutoff of Nonthermal Electrons in Solar Flares

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chinese Journal of Astronomy and Astrophysics 2002年第2期2卷 103-105页

作者： Wei－QunGan You－PingLi 等 Purplemountainobservatory ChineseAcademyofSciencesNanjing210008 NationalAstronomicalObservatories ChineseAcademyofSciencesBeijing100012

Using the method recently developed by Can et al. (2001a, 2002), We investigate the time variation of the lower energy cutoff (Ec) of nonthermal electrons for three BATSE/CGRO hard X-ray events. The result shows that Ec changes with time, from smaller before the peak flux, to larger at the peak, and then back to smaller after the peak. Such a variation of Ec, being a preliminary conclusion for the first time, should be checked in the future by using data with a higher energy resolution.

关键词： Sun: hard X-rays─Sun: gamma-rays─Sun: flares─Sun: particles

Soil water characteristics in mountain poplar stand and its benefits to soil and water conservation in loess hilly region

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Journal of Environmental sciences 1994年第3期6卷 347-354页

作者： Wu Qinxiao Liu Xiangdong Zhao Hongyan Northwestern Institute of Soil and Water Conservation,chinese academy of sciences and Ministry of Water Conservancy),Yangling 712100,china)

The soil physical properties,its water characteristics and the benefits to soil and water conservation in mountain poplar stand were determined and studied. The results of the study show that the compaction in soil profile is relatively *** specific gravity and volume weight of soil increase with deepening of soil horizon. The water infiltration rate of soil in the stand is 17,6 times as high as in *** to the intense absorption of water by root system of plants,a drying layer is formed in soil horizon from 2.3 m to 2.7m,showing that the subsoil moisture is in the state of deficit. The annual water storage capacity in 2 m of soil horizon is 360 mm 370mm,or 63% 65% of annual precipitation. Compared with farmland,mountain poplar stand reduces the surface runoff and soil loss by 70% and 99%,respectively,indicating the great benefits to soil and water conservation.

关键词： mountain poplar soil water characteristics soil and water conservation.

Lithology, kinematics and geochronology related to Late Mesozoic basin-mountain evolution in the Nanxiong-Zhuguang area, South china

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Science china Earth sciences 2004年第8期47卷 673-688页

作者： SHU Liangshu1, DENG Ping1,2, WANG Bin1, TAN Zhengzhong2, YU Xinqi1 & SUN Yan1 1. Department of Earth sciences, nanjing University, nanjing 210093, china 2. Research Institute No.290, CNNC, Shaoguan 512026, china Department of Earth sciences Nanjing University Nanjing China Research Institute No.290 CNNC Shaoguan China

The Nanxiong red-bed basin and its adjacent Zhuguang granite form a distinctive basin-mountain landform in the Nanling region, South china. Research results suggest that the Zhuguang granite is a polyphase composite pluton developed on the metamorphic basement of the paleo-Tethys-paleo-Asian tectonic regime and possesses geometrical and kinematic features of hot-doming extensional tectonics at the middle-upper crustal level, which is considered as a magmatic complex that resulted from the collision-orogeny during the Indosinian Period, the subduction-consuming during the Early Yanshanian Period and the intra-continental basaltic underplating and deep-seated geodynamics during the Late Yanshanian Period. The Nanxiong basin is a Late Cretaceous-Paleogene asymmetric faulted basin that is characterized by a fault boundary on the northern side and an uncomformable boundary on the southern side, its deposit center was migrated gradually from south to north. Structural kinematic results on the basin-mountain coupled zone demonstrate that the ductile and the brittle rheological layers show a quite coincident sense of shear, implying that it is a continuous process from the ductile extensional deformation followed by locally sinistral strike-slip shear at a middle-crustal level to the brittle tensional deformation at a upper-crustal level during formation of granitic doming extensional tectonics. The Zhuguang granite and the Nanxiong faulted basin constructed a semi-graben tectonic system. Lithological and geochemical results suggest that the Late Triassic to Jurassic granitic bodies in the Zhuguang have some similar features: high SiO2, Al2O3, K2O contents, alkalinity index > 2.8, ANKC value > 1.1, LREE-enriched pattern with high REE contents, marked negative Eu anomalies, enrichment in Rb and Th, depletion in Ba and Nb, showing a K-rich and Al-rich calc-alkaline affinity, which suggest a continuous magmatic evolution from Late Triassic to Jurassic. Formation of Nanxiong ba

关键词： lithology,structural kinematics,basin-mountain evolution,SHRIMP age,Zhuguang granite,Nanxiong basin.