滑坡灾害风险评价的系统分析

从系统理论的观点出发,提出了滑坡灾害复杂大系统的概念,并以这一概念为基础,探讨了滑坡灾害风险特征及滑坡灾害风险评价的基本内容,提出并系统地阐述了以滑坡危险性分析、承灾体易损性分析和滑坡灾害破坏损失评估为核心内容的滑坡灾害风险评价的系统理论。     

The application of GIS-based bivariate statistical methods for landslide hazards assessment in the upper Tons river valley,Western Himalaya,India

Landslides are one of the most frequent and common natural hazards in many parts of Himalaya. To reduce the potential risk, the landslide susceptibility maps are one of the first and most important steps in the landslide hazard mitigation. Earth observation satellite and geographical information system-based techniques have been used to derive and analyse various geo-environmental parameters significant to landslide hazards. In this study, a bivariate statistics method was used for spatial modelling of landslide susceptibility zones. For this purpose, thematic layers including landslide inventory, geology, slope angle, slope aspect, geomorphology, slope morphology, drainage density, lineament and land use/land cover were used. A large number of landslide occurrences have been observed in the upper Tons river valley area of Western Himalaya. The result has been used to spatially classify the study area into zones of very high, high, moderate, low and very low landslide susceptibility zones. About 72% of active landslides have been observed to occur in very high and high hazard zones. The result of the analysis was verified using the landslide location data. The validation result shows significant agreement between the susceptibility map and landslide location. The result can be used to reduce landslide hazards by proper planning.     

滑坡灾害风险评价的关键理论与技术方法

滑坡灾害风险评估主要包括滑坡敏感性分析、危险性评价和风险评估3个不同层次的内容。但是,滑坡地质灾害本身的复杂性和滑坡强度的确定、滑坡发生的时空概率估算、承灾体的易损性时空概率分析等难点问题的存在,无疑阻碍了滑坡风险定量评估的推广和应用。在系统分析国内外滑坡灾害风险评估研究成果的基础上,对滑坡灾害风险评价的技术体系进行了总结,提出了不同层次滑坡灾害的研究内容和相应的评价方法;分析了实现滑坡风险有效评价涉及到的难点问题,并结合降雨和地震诱发的滑坡灾害危险性评价国内外的实践,提出了中国未来滑坡灾害风险评价研究的主要内容和技术方法。     

滑坡易发性危险性风险评价例析

从易发性、危险性、风险的概念入手,依据国际上流行和通用的滑坡风险评价与管理理论,分析了易发性评价的内容,包括易发性评价到危险性评价需要增加的评价要素,以及从危险性评价到风险评价需要增加的评价要素,阐明了这三种评价之间的联系和区别。并通过延安宝塔区的滑坡易发性、危险性和风险的评价与区划具体说明三者的做法和结果。     

基于Mamdani FIS模型的滑坡易发性评价研究

滑坡的形成是众多非线性关系的影响因子相互作用的结果,传统滑坡预测方法需要大量实地勘查数据。利用Mamdani FIS(模糊推理系统)模型对三峡库区巴东-秭归段进行滑坡易发性预测,并对结果进行评价。通过地理信息系统(geographic information system,GIS)、遥感(remote sensing,RS)技术和区域地质背景资料获取地形类、生态环境类和地质背景类共3类7种滑坡影响因子,建立了192条相关的推理规则,在Matlab平台下基于Mamdani FIS模型得到研究区滑坡易发性预测指数,并生成滑坡易发性区划图。预测结果的受试者工作特征曲线下的面积值为82.8%,显示滑坡评估效果良好。结果证明,与其他模型相比,基于空间信息技术的Mamdani FIS模型,利用其非线性分析能力和基于专家意见的推理规则,评估滑坡易发性时不需要先验知识支撑,简化了模型使用时对数据的要求。另外,该模型只需通过专家意见改变推理规则就可以应用于不同的地质地理环境区域,显示其较强的适应性。     

Probabilistic landslide susceptibility and factor effect analysis

The susceptibility of landslides and the effect of landslide-related factors at Penang in Malaysia using the geographic information system (GIS) and remote sensing data have been evaluated. Landslide locations were identified in the study area from interpretation of aerial photographs and from field surveys. Topographical and geological data and satellite images were collected, processed, and constructed into a spatial database using GIS and image processing. The factors chosen that influence landslide occurrence were: topographic slope, topographic aspect, topographic curvature and distance from drainage, all from the topographic database; lithology and distance from lineament, taken from the geologic database; land use from Landsat Thermatic Mapper (TM) satellite images; and the vegetation index value from SPOT HRV (High-Resolution Visible) satellite images. Landslide hazardous areas were analyzed and mapped using the landslide-occurrence factors employing the probability–frequency ratio method using the all factors. To assess the effect of these factors, each factor was excluded from the analysis, and its effect verified using the landslide location data. As a result, all factors had relatively positive effects, except lithology, on the landslide susceptibility maps in the study area.     

安徽黄山市徽州区地质灾害危险性评价研究

皖南山区是安徽省地质灾害高发区域。本文选取黄山市徽州区为研究区,根据区内地形地貌和地质构造特点,选取了高程、坡度、坡向、断裂构造、水系、土地覆盖类型、工程地质岩组、人类活动强度等8项致灾因子作为地质灾害危险性评价指标。结合地质灾害野外实地调查成果,采用信息量模型法对研究区进行地质灾害危险性评价,探索建立适合皖南山区的地质灾害危险性评价模型。     

区域滑坡灾害预测预警与风险评价

区域滑坡灾害预测预警是滑坡灾害研究领域的难点和热点。过去10多年来在这方面的研究主要集中在区域降雨与地质环境的结合方面。文章总结了目前国内外滑坡灾害预测预报、预警和风险管理研究现状,认为把滑坡灾害预警预报与风险管理相结合是减灾防灾的需要,也是今后该领域研究的发展趋势。文章从区域滑坡灾害空间预测、时间预警预报的角度提出了滑坡灾害预测预报的分类和理论基础,并在此基础上,利用MapGIS软件平台进行二次开发,建立了基于WebGIS的滑坡灾害信息管理系统和实时预警发布系统。以2004年"云娜"台风期间浙江省永嘉县滑坡灾害预警预报为例,进行了滑坡危险性预测、人口易损性预测、经济易损性预测到风险预测的实例研究。     

国道213汶川—松潘段滑坡隐患遥感识别与易发性评价

国道213汶川—松潘段位于强震山区,滑坡灾害频发,每年都会因滑坡灾害导致交通中断,迫切需要查明沿线滑坡隐患的空间分布,并对其易发性进行评价。利用光学遥感和InSAR综合遥感技术对沿线滑坡隐患进行识别,共识别滑坡隐患288处,其中InSAR探测出有形变的滑坡隐患点27处。以识别出的滑坡隐患为评价样本,选取高程、坡度、坡向、地表曲率、工程地质岩组、归一化植被指数(normalizied difference vegetation index,NDVI)、距道路距离、距河流距离、距断层距离等9个影响因素作为评价因子,采用Logistic回归模型评价该沿线滑坡隐患易发性,评价结果可为国道213汶川—松潘段滑坡灾害防治提供参考。     

Landslide hazard mapping at Selangor, Malaysia using frequency ratio and logistic regression models

The aim of this study is to evaluate the landslide hazards at Selangor area, Malaysia, using Geographic Information System (GIS) and Remote Sensing. Landslide locations of the study area were identified from aerial photograph interpretation and field survey. Topographical maps, geological data, and satellite images were collected, processed, and constructed into a spatial database in a GIS platform. The factors chosen that influence landslide occurrence were: slope, aspect, curvature, distance from drainage, lithology, distance from lineaments, land cover, vegetation index, and precipitation distribution. Landslide hazardous areas were analyzed and mapped using the landslide-occurrence factors by frequency ratio and logistic regression models. The results of the analysis were verified using the landslide location data and compared with probability model. The comparison results showed that the frequency ratio model (accuracy is 93.04%) is better in prediction than logistic regression (accuracy is 90.34%) model.     

承灾体易损性评估模型与滑坡灾害风险度指标

承灾体易损性定量评估是制约滑坡灾害风险评估研究的瓶颈问题。为此,以滑坡体冲击冲量为致灾强度指标、建筑物整体抗剪力为抗灾性能指标,推导出典型承灾体易损性定量评估模型。在此基础上,考虑滑体运动特征参数随机性对易损性的影响,提出风险曲线和最大风险度指标的概念,以反映滑坡灾害成灾全过程中不确定性对灾害后果的影响。并采用该模型分析了坡体几何特征参数、受灾体空间位置以及受灾体抗灾性能对易损性的影响规律。将风险度指标应用于算例分析,并与以往方法进行了比较,分析发现,建立的易损性定量评估模型可以反映二维简化情况下受灾体毁损程度与各种影响因素之间关系的基本规律,为易损性定量评估提供了一种途径。     

油气长输管道滑坡地质灾害危险性评价专家系统研究

以运营的油气长输管道工程为依托,在收集、整理、综合分析既有资料基础上,通过对大量滑坡案例进行分析,明确了滑坡地质灾害的主要诱发因素与稳定性控制指标,建立了滑坡危险性评价指标体系。应用专家系统研究方法,建立油气长输管道线路滑坡地质灾害危险性评价专家系统,并对具体工程进行了地质灾害危险性评估,结果符合实际,可为油气长输管道工程地质灾害减灾防灾提供技术支撑。     

Predictive landslide susceptibility mapping using spatial information in the Pechabun area of Thailand

For predictive landslide susceptibility mapping, this study applied and verified probability model, the frequency ratio and statistical model, logistic regression at Pechabun, Thailand, using a geographic information system (GIS) and remote sensing. Landslide locations were identified in the study area from interpretation of aerial photographs and field surveys, and maps of the topography, geology and land cover were constructed to spatial database. The factors that influence landslide occurrence, such as slope gradient, slope aspect and curvature of topography and distance from drainage were calculated from the topographic database. Lithology and distance from fault were extracted and calculated from the geology database. Land cover was classified from Landsat TM satellite image. The frequency ratio and logistic regression coefficient were overlaid for landslide susceptibility mapping as each factor’s ratings. Then the landslide susceptibility map was verified and compared using the existing landslide location. As the verification results, the frequency ratio model showed 76.39% and logistic regression model showed 70.42% in prediction accuracy. The method can be used to reduce hazards associated with landslides and to plan land cover.     

基于多期DEM和滑坡强度的滑坡风险评估

滑坡危险性定量评估是滑坡风险评估中的关键和难点,也是当前国际风险管理研究中的热点问题.以滑坡密集分布的黑方台南塬为研究区,以32处典型滑坡为研究对象,依据多期三维数字高程模型(DEM),提出了一种基于强度的滑坡危险性定量评估技术方法.根据多期三维地形信息的解译及野外调查,编制多期滑坡分布图,计算滑坡活动的频率.利用GIS技术,利用滑坡体积与速度的乘积计算滑坡强度.将滑坡危险性定义为滑坡频率和滑坡强度的乘积,同时调查和分析了黑方台地区各类承灾体的类型、价值及其在相应滑坡强度下的易损性,在此基础上开展了单体滑坡风险评估和黑方台南塬滑坡风险区划.     

滑坡变形空间评价的位移速率比方法研究

实测数据表明,松散土质斜坡和具有时效变形特征的岩质斜坡的滑坡变形往往具有蠕变特点,即从开始出现变形到最终失稳破坏一般需经历初始变形、等速变形和加速变形3个阶段。基于典型的滑坡累积位移-时间曲线特征,提出了采用位移速率比作为通用指标来判定滑坡上各点变形阶段的方法：多个连续时段均为等速变形即相邻位移速率比位于0～2之间时,认为进入等速变形阶段;当位移速率比大于2时,初步认为,其进入加速变形阶段。结合典型实例建立了位移速率比判定滑坡上各点变形阶段的判定标准：在滑坡位移速率比大于2之后,滑坡体进入加速变形阶段,对加速变形阶段可再作进一步细分：位移速率比为2～6时,为滑坡体的初加速阶段,为6～8时,滑坡体进入中加速阶段,大于8则为临滑阶段。基于地理信息系统（Geographic information system,简称GIS）平台,建立了滑坡变形空间评价的位移速率比方法,并对金坪子滑坡的空间变形状态进行了评价,验证了该方法的可行性和合理性。     

Monitoring of hazards and urban growth in Villavicencio, Colombia, using scanned air photos and satellite imagery

A method is presented to monitor the development of geomorphic hazard areas by overlaying time series of air photos in a digital image processing system. The present study deals with such hazards affecting an urban area, Villavicencio at the foot of the eastern Andes in Colombia. The relevant windows of the air photos are digitized by flat-bed scanning and then transformed geometrically to be overlain on SPOT panchromatic imagery where available. The 10 m resolution of the satellite imagery allows, in practice, sufficient detail to bring out the differences, which are a yardstick to monitor the development of the phenomenon over time. Where no SPOT panchromatic imagery is available, one of the photos may be taken as a reference; registration to a topographic base map is also possible. A development over time to the present hazardous situations can be read from the analyzed imagery. Air photo series dating back to 1937 are available for this research, in the context of a geomorphic hazards study currently undertaken in the eastern Colombian Andes front where it pushes against the Llanos Orientales. The mountain front is quite steep and high, and the contact with the plains is very abrupt. A thrust fault zone in which the rocks are strongly mylonitized, marks the eastern front. Villavicencio lies just below this zone, but its main access road has to cross it. The terrain is mostly made up of Mesozoic and Palaeozoic sedimentary series, with prominent black lutites; Tertiary sedimentaries are found in the foreland. All rocks are strongly folded and faulted. Precipitation is in the order of 3500–5500 mm per year. Records on river discharge events are scarce or absent. Seismic events are frequent in the area. This area is prone to strong and rapid geomorphic processes posing hazards to the inhabitants. The town of Villavicencio is the gateway to the Llanos Orientales. It is the major town for hundreds of kilometres around, and a commercial, educational and health centre for the whole eastern region of Colombia. It is connected to Santa Fe de Bogotá, the national Capital, by the only highway to the Llanos, which traverses very difficult terrain through the Eastern Andes, and is cut frequently by landslides, bridge collapse etc., as a result of the torrential rainfall and the instability of the terrain. A major hazard is a big landslip known as the Mirador, close to Villavicencio, on the main road to Bogotá. Its rapid advancement has caused numerous road closures; its growth could be monitored on the scanned and registered air photos. The shifting and flooding of the Guatiquía River threatens the left bank, on which the airport of Villavicencio is situated. The development of the flood hazard, and the areal extent of the area threatened, is monitored and measured on the scanned and referenced air photos. The areal growth of the town of Villavicencio itself could likewise be monitored and measured. This revised version was published online in July 2006 with corrections to the Cover Date.     

基于风险评价的黄土滑坡分类及特征

整理分析了国际上通用的滑坡分类方法,并对国内有关的滑坡分类体系汇总,在此基础上,将运动形式、规模大小或运动速度综合考虑,形成一个二维的分类表,提出了基于风险评价的黄土滑坡分类方法。根据该方法,黄土滑坡可分为剥落、倾倒、崩塌、滑塌、滑动、泥流、复合型7个类,每一大类再分为不同的亚类或小类,共将黄土滑坡分为7个大类,10个亚类,38个小类。每一种黄土滑坡的变形破坏方式和运动学特征不同,具有不同的规模、速率和滑移距离,因此其风险特征也不同,对不同类型黄土滑坡的风险特征做了分析和总结。     

基于GIS的巴东新县城滑坡灾害风险系统

本文提出了基于GIS的滑坡灾害风险预测系统流程。并将滑坡灾害风险评价模型与GIS技术先进的图形处理和空间分析功能相结合,建立了巴东县新县城区滑坡灾害风险预测系统。系统由信息管理子系统、危险性预测子系统、易损性预测子系统、风险预测子系统四大子系统构成。系统在对相关信息进行采集、存贮、检索和管理的基础上,结合物元模型、BP模型等专业预测模型,实现了滑坡灾害危险性、易损性评价,最终取得了滑坡灾害风险分布图,为三峡库区内各县的滑坡灾害信息管理和风险预测提供了新途径。预测成果可为研究区的国土规划和移民工程的顺利实施提供依据和保障。     

RS、GIS在贵州省环境地质综合调查中的应用--以崩塌、滑坡、泥石流调查为例

通过遥感图像的目视解译吸人机交互解译来识别地质灾害体,并在GIS系统支持下参考区域地质、地貌背景,对地质灾害发育规律和分布特征作进一步分析。可大大提高工作效率和成果的准确性,对于区域性地质灾害(尤其是崩塌、滑坡和泥石流)的调查目前是最为有效的方法。这个方法为地质灾害的地学分析提供了一个直观的工作平台,对于发现其各种地学规律,提高研究程度帮助极大。