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1.
舟曲三眼峪泥石流风险评价 总被引：1，自引：0，他引：1
以往的泥石流风险评价仅局限于某个单一时点的风险分析,而对泥石流发生前后和治理前后的评价因子变化情况以及由此带来的风险变化则缺少分析和研究。选择舟曲三眼峪泥石流作为研究对象,采用单沟泥石流风险度评价模型,利用现场调查、工程勘查、工程设计等资料,分析“8．8”前、现状情况下和治理后3个不同时点的评价因子变化情况,得到各自的危险度和易损度评价参数;分别对这3个时点的泥石流风险度做了计算,得到各自风险度的大小;最后对评价结果做了讨论,分析了不同时点风险度发生变化的具体原因。 相似文献
2.
国际滑坡风险评估与管理指南研究综述 总被引：7，自引：0，他引：7
总结了国际主流滑坡风险评估与管理技术指南的进展和现状,综述了滑坡风险管理范畴中包含的理论和技术框架,研究精度和层次,滑坡编录、易发性、危险性和风险分区研究的技术方法;指出了滑坡风险分区成果的误差来源和可靠性验证方法;基于滑坡风险分区的研究成果,提出了土地利用规划中风险控制措施的建议。总结了主流国家和地区滑坡风险管理的发展历程和经验,结合中国地质灾害防灾减灾的现状,强调了出版滑坡风险评估与管理指南的紧迫性,并展望了滑坡等突发地质灾害风险评估与管理的发展前景。 相似文献
3.
Arid and semi-arid regions are susceptible to high levels of erosion.A rapid and cost effective methodological erosion assessment for these regions is required to describe and monitor the processes that control erosion.This study uses remote sensing to describe the contribution of several factors that control erosion.Topography,land use,vegetation density,soil properties and climatic proxies are used to determine erosion risk and to provide basic maps of water and soil conservation practices. A hierarchi... 相似文献
4.
Debris flows belong to sudden disasters which are difficult to forecast. Thus, a detailed and coherent hazard assessment seems a necessary step to prevent or relieve such disasters and mitigate the risk effectively. Previous researchers have proposed several methods, such as regression analysis, fuzzy mathematics, and artificial neural networks for debris-flow hazard assessment. However, these methods need further improvements to eliminate the high relativity existing in their results. The current study reported a similarity-based debris-flow hazard assessment model to determine hazard levels of debris flow in regions, with steps like determining hazard-level-type regions, selecting environmental factors and calculating the similarities between the assessment-pending regions and assessed hazard-level-type ones. This methodology was then employed to assess the regional debris hazard of Yunnan Province in China as a case study and was verified via comparison with field surveys. As the results indicate, the proposed similarity-based debris-flow risk assessment model is simple and efficient and can improve the comparability and reliability of the assessment to some degree. 相似文献
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6.
提出了基于子集模拟的边坡风险评估的高效随机有限元法（RFEM）,推导了基于子集模拟的边坡失效概率和失效风险的计算公式,并给出了基于高效RFEM的边坡可靠度分析和风险评估流程图。采用一个边坡算例验证了所提方法的有效性。结果表明,基于子集模拟的高效RFEM可以视为是对基于蒙特卡洛模拟的传统RFEM的改进,显著地提高了失效概率和失效风险的计算效率以及失效样本的产生能力,非常适用于分析小失效概率的可靠度问题,极大地增强了RFEM在边坡可靠度分析和风险评估中的实用性。高效RFEM将边坡的整体失效风险分解为对应不同概率水平的边坡失效风险,并量化了它们对整体风险的相对贡献度。在该方法中,边坡可靠度分析和风险评估与确定性边坡有限元分析互不耦合,极大地简化了它们的计算过程。此外,土体不排水抗剪强度的竖向空间变异性对边坡失效风险具有显著的影响。 相似文献
7.
Spatiotemporal dynamics: the need for an innovative approach in mountain hazard risk management 总被引：5，自引：4，他引：1
Sven Fuchs Margreth Keiler Sergey Sokratov Alexander Shnyparkov 《Natural Hazards》2013,68(3):1217-1241
Starting with an overview on losses due to mountain hazards in the Russian Federation and the European Alps, the question is raised why a substantial number of events still are recorded—despite considerable efforts in hazard mitigation and risk reduction. The main reason for this paradox lies in a missing dynamic risk-based approach, and it is shown that these dynamics have different roots: firstly, neglecting climate change and systems dynamics, the development of hazard scenarios is based on the static approach of design events. Secondly, due to economic development and population dynamics, the elements at risk exposed are subject to spatial and temporal changes. These issues are discussed with respect to temporal and spatial demands. As a result, it is shown how risk is dynamic on a long-term and short-term scale, which has to be acknowledged in the risk concept if this concept is targeted at a sustainable development of mountain regions. A conceptual model is presented that can be used for dynamical risk assessment, and it is shown by different management strategies how this model may be converted into practice. Furthermore, the interconnectedness and interaction between hazard and risk are addressed in order to enhance prevention, the level of protection and the degree of preparedness. 相似文献
8.
In recent years, through the availability of remotely sensed data and other national datasets, it has become possible to conduct national-scale flood risk assessment in England and Wales. The results of this type of risk analysis can be used to inform policy-making and prioritisation of resources for flood management. It can form the starting point for more detailed strategic and local-scale flood risk assessments. The national-scale risk assessment methodology outlined in this paper makes use of information on the location, standard of protection and condition of flood defences in England and Wales, together with datasets of floodplain extent, topography, occupancy and asset values. The flood risk assessment was applied to all of England and Wales in 2002 at which point the expected annual damage from flooding was estimated to be approximately £1 billion. This figure is comparable with records of recent flood damage. The methodology has subsequently been applied to examine the effects of climate and socio-economic change 50 and 80 years in the future. The analysis predicts increasing flood risk unless current flood management policies, practices and investment levels are changed – up to 20-fold increase in real terms economic risk by the 2080s in the scenario with highest economic growth. The increase is attributable primarily to a combination of climate change (in particular sea level rise and increasing precipitation in parts of the UK) and increasing economic vulnerability. 相似文献
9.
A “simple” geomatics-based approach for assessing water erosion hazard at montane areas 总被引：1，自引：0，他引：1
Soil erosion by water is recognised as a worldwide land degradation issue, particularly in arid and semi-arid regions. The aim of this study is to apply the powerful capabilities of advanced remote sensing and geographic information system techniques to identify the areas at risk to water erosion. This study presents the assessment of water erosion in mountainous areas (eastern Aures, Algeria) based on three main factors: the friability of the bedrock, degree of slope and density of vegetation cover. Alsat1 image was used to produce land use and vegetation (NDVI) maps. Digital elevation model was used in constructing the slope gradient map. The erosion risk map was obtained by the combination of indices assigned to thematic layers following multicriteria decision rules. Water erosion was generally not concerning in the eastern Aures (slight risk = 33 %, moderate risk = 44 % of the area). This simple–qualitative approach gave good results for assessing soil erosion equally to quantitative methods since 89.55 % of field verifications were accurate. The non-alarming state and the low rate of severe and extremely severe risk to erosion are due to (1) the low steep slopes, (2) the good quality of vegetation (forests with thick undergrowth), and which are occurring on (3) resistant materials of the substratum, and (4) the low human pressure. Results of this study, which may be conducted with reasonable costs and accuracy over large areas, are of significant help in prioritising areas in decision making and sustainable planning. 相似文献
10.
Heat wave risk assessment and mapping in urban areas: case study for a midsized Central European city,Novi Sad (Serbia) 总被引：1，自引：0，他引：1
Stevan Savić Vladimir Marković Ivan Šećerov Dragoslav Pavić Daniela Arsenović Dragan Milošević Dragan Dolinaj Imre Nagy Milana Pantelić 《Natural Hazards》2018,91(3):891-911
Risk assessment and mapping methodologies for heat waves as frequently occurring hazards in central and southeastern Europe were applied in this study, and the impact of heat waves on the mortality of urban populations was determined as part of the assessment. The methodology for conducting the heat wave risk assessment is based on European Commission’s Guidelines for Risk Assessment and Mapping. The Novi Sad (Serbia) urban area was studied during summer 2015, which was one of the hottest summers in the last few decades. In situ air temperature measurements from urban stations and mortality of urban populations were used. Nocturnal urban heat island (UHI) intensity values between the various built-up zones and natural surrounding areas were used for the hazard level calculation. Temperature data from 9 p.m. to 5 a.m. were used because during the night, the UHI intensity reached its maximum values. The average daily number of deaths by LCZs was used to define the impact level of the vulnerability index. Calculations for both hazard levels were completed during two intensive heat waves (in July and August 2015) when it was expected that there may be a high level of risk. The results and maps show that the urban area is complex, and the heat wave risk on the population is not uniform. The most densely built-up areas (LCZs 2, 5 and 6) have very high or high risk values that are influenced by a higher rate of mortality. The obtained results and maps can be used by local authorities to prevent and mitigate climate-related hazards, for medical institutions as well as urban planners and for ancillary local, regional or national services. According to these results, the local authorities could define hot spots where they can place medical and rescue teams and install points with water supplies, etc. 相似文献
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12.
Huang Bolin Chen Lide Peng Xuanming Liu Guanning Chen Xiaoting Dong Haogang Lei Tianci 《Landslides》2010,7(1):1-11
In 2007 and 2008, six big damaging rockfalls occurred at four sites in Wu Gorge, the second gorge of the Three Gorges, China.
Detailed surveys and aerial-photographic interpretation identified 104 potentially dangerous rock masses. This paper reviews
previous rock-mass risk ratings, examines dangerous rock-mass structure and presents a new assessment system for rockfall
risk (ASRFR) in the Wu Gorge area. The ASRFR considers 15 factors: seven factors for hazard and eight factors for consequence.
Relative importance weights for these factors are ascertained using an analytic hierarchy process. Using an equation to calculate
the risk, the 104 dangerous rock masses were divided into three risk groups: high risk (33 sites), medium risk (33 sites)
and low risk (38 sites). The ASRFR analysis can be used to divide the shipping route through the Wu Gorge into seven courses
each of one of three classes: safe-route regions, yellow-alarm regions and red-alarm regions. The system provides geological
information and a rockfall-risk management tool for local government and the shipment-route department. 相似文献
13.
Flood risks in a dynamic urban agglomeration: a conceptual and methodological assessment framework 总被引：2，自引：1，他引：1
Annemarie Müller 《Natural Hazards》2013,65(3):1931-1950
The analysis of risk and its causes is a crucial prerequisite for the development of risk prevention and mitigation measures in the scope of disaster risk management. This paper investigates on the problem of annually occurring floods in Santiago de Chile applying a framework for risk assessment, especially developed for the usage in a large urban area. A case-specific set of variables and indicators was compiled to show the relevant components and their interrelations influencing the flood risk and to provide a tool for monitoring and evaluating their changes over time. Methods for gathering information about the three components of risk, that is, hazard, elements at risk, and vulnerability, comprise the interpretation of very high resolution satellite data, the analysis of GIS, and census data as well as household surveys and expert interviews. The work shows how the assessment framework can be applied in practice to derive a geodata-based flood risk map at the scale of the administrative unit of a building block that can be used as a local decision-making tool. 相似文献
14.
Assessment on agricultural drought vulnerability in the Yellow River basin based on a fuzzy clustering iterative model 总被引：3，自引：2，他引：1
Di Wu Deng-Hua Yan Gui-Yu Yang Xiao-Gang Wang Wei-Hua Xiao Hai-Tao Zhang 《Natural Hazards》2013,67(2):919-936
Drought is one of the major natural disasters occurring in China and causes severe impacts on agricultural production and food security. Therefore, agricultural drought vulnerability assessment has an important significance for reducing regional agricultural drought losses and drought disaster risks. In view of agricultural drought vulnerability assessment with the characteristics of multiple factors and uncertainty, we applied the fuzzy comprehensive evaluation framework to agricultural drought vulnerability model. The agricultural drought vulnerability assessment model was constructed based on the multi-layer and multi-index fuzzy clustering iterative method, which can better reveal the drought vulnerability (including sensitivity and adaptation capacity). Furthermore, the cycle iterative algorithm was used to obtain the optimal index weight vector of a given accuracy by setting the objective function. It provides a new approach to weight determination of agricultural drought vulnerability assessment. In this study, agricultural drought vulnerability of 65 cities (as well as leagues and states) in the Yellow River basin was investigated using a fuzzy clustering iterative model and visualized by using GIS technique. The results showed clear differences and regularities among the spatial distribution of agricultural drought vulnerability of different regions. A large number of the regions in the basin consisted of those exhibiting high to very high vulnerability and were mainly distributed throughout Qinghai, Gansu, northern Shaanxi, and southern Shanxi, accounting for 46 % of the total assessment units. However, the regions exhibiting very high vulnerability were not significantly affected by droughts. Most of the regions exhibiting moderate vulnerability (21.5 % of the assessment units) were mainly concentrated among agricultural irrigation areas, where agriculture is highly sensitive to droughts, and drought occurrence in these regions will likely cause heavy losses in the future. The regions exhibiting slight to low vulnerability were relatively concentrated, accounting for 32.3 % of the assessment units, and were mainly distributed in the plains of the lower reaches of the Yellow River, where the economy was rather well developed and the agricultural production conditions were relatively stronger. 相似文献
15.
面向灾害风险评估的热带气旋路径及强度随机模拟综述 总被引：1，自引：0，他引：1
历史热带气旋记录时间序列较短空间差异大,热带气旋灾害风险评估经常面临样本不足,特别是超强台风及巨灾记录历史样本的问题,从而导致传统概率统计方法失效。过去20多年来,逐渐发展出一套完整的方法体系进行热带气旋路径及强度随机模拟,其特点是充分利用历史总体样本信息,生成大量符合历史样本特征的热带气旋路径及强度随机事件样本集,从而有效地解决了局地历史样本不足的问题。在回顾热带气旋的年频次、季节分布、路径分布、强度及影响范围时空规律研究进展基础上,系统综述了用于热带气旋路径及随机模拟的起始点模型、行进模型、终止点模型、洋面强度模型、陆地衰减模型及结果检验方法等领域的进展及不足,然后对其在世界各地的应用进行了概述,并对未来研究改进方向及应用领域进行了展望。 相似文献
16.
Dongchuan City is highly threatened by debris-flow disasters originating from Shengou gully, a typical debris-flow gully along
Xiaojiang River in Yunnan Province (Kang et al. 2004). Shengou gully is studied, and a hazard assessment with numerical simulation is developed using ArcGIS 9.2 software. Debris-flow
numerical simulation is an important method for predicting debris-flow inundation regions, zoning debris-flow risks, and helping
in the design of debris-flow control works. Meanwhile, vulnerability measurement is essential for hazard and risk research.
Based on the self-organized map neural network method, we combine the six vulnerability indicators to create an integrated
debris-flow vulnerability map that depicts the vulnerability levels of Dongchuan City in Shengou Basin. Based on the risk
assessment (including hazard assessment and vulnerability assessment), we adopt the principal–agent theory and use the risk
degree of debris flows as an important index to build the insurance model and analyze the insurance premium of debris-flow
disasters in Dongchuan City. This paper discusses the model and mechanism of property insurance in debris-flow risk regions
and aims to provide technical support for insurance companies to participate in disaster prevention and reduction. 相似文献
17.
The landslide hazard is one of the geological hazards in mountainous zone. Its occurrence is controlled by many factors. To assess the risk level of landslide in Shiwangmiao accurately, intuitionistic fuzzy sets-Topsis model is introduced at first; secondly, the decisive matrix about the intuitionistic fuzzy sets is established, and the index weight coefficients considering the uncertainty of assessment indices are determined by using the Entropy weight method, then the weighed decisive matrix is obtained. Finally, degree of membership at different levels about the landslide is determined based on the ranking sequence of degree of membership, the risk level corresponding to the maximum degree of membership is final assessment level. The conclusions are drawn that accurate rate of risk estimation about landslide hazards is very high based on the intuitionistic fuzzy sets model in comparison with the current specifications, and the method is feasible for the risk assessment of landslide hazards, so it provides a new method and thoughts to assess the risk level of landslide in future.
相似文献18.
《Applied Geochemistry》2002,17(8):1029-1045
The advantages of quantitative environmental risk assessment techniques over the more commonly used qualitative approach is widely accepted. Yet, correct implementation of quantitative risk assessment is a difficult task, given the present state of understanding of the environmental processes. One important parameter related to the level of risk is the extent and geographic spread of pollutants. Geographic information systems (GIS) provide a very powerful and highly flexible tool that increases the sophistication of the risk assessment methodology. Through spatial representation, the estimated risk becomes more comprehensive, thus facilitating the decision making process. In addition, valuable qualitative information can be incorporated into the risk assessment procedure with the help of GIS. This paper illustrates a methodology which incorporates a probabilistic risk assessment model within a GIS. The case study utilised to illustrate the methodology is a large industrial area around a number of decommissioned minerals production and processing sites with known high heavy metal loads at Lavrio, Greece. The spatial distribution of Pb concentration in soils was derived from 425 soil samples collected over a total area of 120 km2. A risk assessment model was constructed to simulate and assess the risk associated with high Pb loads in soils in the study area. The methodology consists of a typical exposure assessment model, constructed for adult and child populations. The Pb exposure for both populations is compared with relevant reference dose levels providing hazard quotients. The results of the quantitative risk assessment study are analysed and presented in the form of GIS maps covering the study area. 相似文献
19.
The assessment of the risks associated with contamination by elevated levels of pollutants is a major issue in most parts
of the world. The risk arises from the presence of a pollutant and from the uncertainty associated with estimating its concentration,
extent and trajectory. The uncertainty in the assessment comes from the difficulty of measuring the pollutant concentration
values accurately at any given location and the impossibility of measuring it at all locations within a study zone. Estimations
tend to give smoothed versions of reality, with the smoothing effect being inversely proportional to the amount of data. If
risk is a measure of the probability of pollutant concentrations exceeding specified thresholds, then the variability is the
key feature in risk assessment and risk analysis. For this reason, geostatistical simulations provide an appropriate way of
quantifying risk by simulating possible “realities” and determining how many of these realities exceed the contamination thresholds,
and, finally, provides a means of visualizing risk and the geological causes of risk. This study concerns multivariate simulations
of organic and inorganic pollutants measured in terrain samples to assess the uncertainty for the risk analysis of a contaminated
site, an industrial site in northern Italy that has to be remediated. The main geostatistical tools are used to model the
local uncertainty of pollutant concentrations, which prevail at any unsampled site, in particular by means of stochastic simulation.
These models of uncertainty have been used in the decision-making processes to identify the areas targeted for remediation. 相似文献
20.
Use of Systematic, Palaeoflood and Historical Data for the Improvement of Flood Risk Estimation. Review of Scientific Methods 总被引：2，自引：0，他引：2
Gerardo Benito Michel Lang Mariano Barriendos M. Carmen Llasat Felix Francés Taha Ouarda Varyl Thorndycraft Yehouda Enzel Andras Bardossy Denis Coeur Bernard Bobée 《Natural Hazards》2004,31(3):623-643
The catastrophic floods recently occurring in Europe warn of the critical need forhydrologic data on floods over long-time scales. Palaeoflood techniques provideinformation on hydrologic variability and extreme floods over long-time intervals(100 to 10,000 yr) and may be used in combination with historical flood data (last1,000 yr) and the gauge record (last 30–50 yr). In this paper, advantages anduncertainties related to the reconstruction of palaeofloods in different geomorphologicalsettings and historical floods using different documentary sources are described.Systematic and non-systematic data can be combined in the flood frequency analysisusing different methods for the adjustment of distribution functions. Technical toolsintegrating multidisciplinary approaches (geologic, historical, hydraulic and statistical)on extreme flood risk assessment are discussed. A discussion on the potential theoreticalbases for solving the problem of dealing with non-systematic and non-stationary data ispresented. This methodology is being developed using new methodological approachesapplied to European countries as a part of a European Commission funded project (SPHERE). 相似文献