地质灾害土地资源易损性评价定量探讨

地质灾害风险评估中对土地资源易损性考虑较少,作为自然资源的主要承灾体,土地资源应和人口和物质财富一样进行定量化研究。在地质灾害评价理论和土地资源价值理论的基础上,探讨了地质灾害风险评估中的土地资源易损性评估的技术方法。易损性的影响因素是灾害强度和土地资源承灾能力,承灾能力的影响因素是土地利用方式、土壤类型等,基于此,建立了数学模型进行易损性计算,核算了土地资源的经济价值、社会价值、生态价值,进行了综合易损性计算和土地资源易损性区划,并在西乡县进行了实例验证。     

Methodology for the assessment and classification of regional vulnerability to natural hazards in China: the application of a DEA model

This paper presents a new method for quantifying vulnerability to natural hazards in China. As an important area of vulnerability research, quantitative assessment of vulnerability has raised much focus in academia. Presently, scholars have proposed a variety of methods for quantitative assessment, which usually create an index of overall vulnerability from a suite of indicators, based on the understanding of the cause or mechanism of vulnerability. However, due to the complex nature of vulnerability, this approach caused some arguments on the indicator selection and the weight set for subindices. A data envelopment analysis?Cbased model for the assessment of the regional vulnerability to natural disasters is presented here to improve upon the traditional methods, and a new approach for the classification of vulnerability is proposed. The vulnerability to natural hazards in China??s mainland is illustrated as a case study. The result shows that the overall level of vulnerability to natural hazards in mainland China is high. The geographic pattern shows that vulnerability is highest in western China, followed by diminishing vulnerability in central China, and lowest vulnerability levels in eastern China. There is a negative correlation between the level of vulnerability and the level of regional economic development.     

Social vulnerability assessment to seismic risk using multicriteria analysis: the case study of Vila Franca do Campo (S?o Miguel Island, Azores, Portugal)

The increase in the frequency and magnitude of disasters triggered by earthquakes in different regions of the Earth is a major challenge to contemporary societies. The awareness that disasters and risk are processes structured on spatial?Ctemporal interactions maintained at the social-ecological system between the natural hazards and the vulnerabilities of socioeconomic, political and physical nature becomes utterly important in the increase of social systems?? resilience. Thus, the assessment of social vulnerability plays a decisive role in understanding the factors that distinguishes individuals, households and communities, in terms of their ability to anticipate, cope with, resist to and recover from the impact of disasters triggered by natural hazards. This article presents a geographic information system (GIS)-based approach model to assess the social vulnerability to seismic risk using multicriteria analysis (MCA) techniques, in a group decision-making process. The methodology applied to the municipality of Vila Franca do Campo (S?o Miguel Island, Azores, Portugal) identified moderate social vulnerability values at the neighbourhood level and higher social vulnerability values for the built environment and demographic characteristics of the social groups. The social vulnerability patterns make a clear distinction between the older/historical urban cores and the new urban areas. In the first case, the presence of ancient buildings constructed with materials of low resistance to earthquakes coupled with a higher population density and the traits of demographic and socioeconomic frailties of the social groups, results in higher vulnerability values. This pattern is common in the historic centre of S. Miguel district, Ribeira das Taínhas, northern areas of água de Alto and western and eastern neighbourhoods of Ponta Gar?a. The new urban areas, mainly found in S. Pedro, central areas of água de Alto, S. Miguel and Ponta Gar?a districts, have lower values of social vulnerability due to changes in the built, demographic and socioeconomic environments. Results recommend the integration of social vulnerability indexes into seismic risk mitigation policies and emergency management planning.     

Assessing the resilience of Delhi to climate-related disasters: a comprehensive approach

The study addresses disaster risks in Delhi through a resilience approach. It utilizes the Climate Disaster Resilience Index (CDRI) tool, which assesses disaster resilience from five dimensions: physical, social, economic, institutional, and natural. Each dimension comprises 5 parameters, and each parameter consists of 5 variables. The study is carried out in the nine revenue districts of Delhi and reveals that East Delhi is least resilient and New Delhi is most resilient. The CDRI analysis in East Delhi points out the urgent need to focus on key parameters such as housing and land use, population, intensity and frequency of natural hazards, ecosystem services, and land use in natural terms. On the other hand, New Delhi is the most resilient due to all five dimensions, where most significant parameters responsible for its high resilience are housing and land use, population, income, employment, intensity and frequency of natural hazards, ecosystem services, and land use in natural terms. In addition, the overall results of all nine districts show an inverse relationship between resilience score and population density. For example, districts with higher population density show low resilience and vice versa. Moreover, districts located on hazard-prone areas show low resilience. For example, East Delhi and North East Delhi scored low resilience because they both are situated on the Yamuna flood catchment areas. The study further develops key suggestions that are required to address disaster risk in all nine districts of Delhi and discusses future implications of CDRI to address city??s vulnerability. The approach??s distinctness is reflected through its consideration of micro-level diversities and presents some implications to resilience.     

Analysis of social vulnerability to hazards in China

To improve natural disaster management, it is important to recognize the variability of the vulnerable populations exposed to hazards and to develop location-based emergency plans accordingly. This paper presents a mathematical model to establish a model of social vulnerability index (SoVI), which includes 12 social variables, and the regional social vulnerability to natural hazards was formulated by them. Taking a city as statistical unit, the variability of vulnerability to natural hazards was explored among the 323 cities based on the SoVI. The results indicate that vulnerability is a location-based regional phenomenon, with the most vulnerable cities being located in the southwest of China and the eastern areas being generally less vulnerable. The results will be helpful for policy makers to formulate disaster management plans, which can be beneficial for people in more vulnerable areas who are responding to, coping with, and recovering from natural disasters.     

Assessment of provincial social vulnerability to natural disasters in China

Assessment of social vulnerability has been recognized as a critical step to understand natural hazard risks and to enhance effective response capabilities. Although significant achievements have been made in social vulnerability researches, little is know about the comprehensive profile of regional social vulnerability in China. In this study, the social vulnerability to natural hazards was firstly divided into socioeconomic and built environmental vulnerability. Then, using factor analysis, we identified the dominant factors that influence the provincial social vulnerability in China to natural hazards based on the socioeconomic and built environmental variables in 2000 and 2010 and explored the spatial patterns of social vulnerability. The results indicated that the provincial social vulnerability in China showed significant regional differences. The social vulnerability in the southeastern and eastern regions of China was greater than its northern and central parts over the past decade. Economic status, rural (proportion of agricultural population and percentage of workers employed in primary industries), urbanization, and age structure (children) were the dominant driving forces of variations in provincial socioeconomic vulnerability in two studied years, while lifelines and housing age could explain most of changes in built environmental vulnerability in 2000 and 2010. There were no statistically significant correlations between social vulnerability and disaster losses (p > 0.05), indicating the impact of disasters was also related to the intensity of hazards and exposure. Disaster relief funds allocated to each province of China depended more on its disaster severity than the regional integrated social vulnerability over the past decade. These findings would provide a scientific base for the policy making and implementation of disaster prevention and mitigation in China.     

Vulnerability and risk: comparing assessment approaches

The concepts vulnerability and risk are of great importance in the fields of climate change and natural hazards. Confusion is asserted in the terminology used by the respective communities, and a large conceptual literature has not solved this problem. This affects the communication within and between the two communities and the comparison of results from vulnerability and risk assessments. This paper argues that the main difference between methods to assess vulnerability and risk in the climate and the disaster communities is not a conceptual one, but rather different terminologies are used. This point is made using a formal framework of vulnerability to climate change that makes the structure of vulnerability and risk assessments explicit. The framework distinguishes three assessment approaches in the field of vulnerability to climate change, which recur—under different labels—in the risk assessment approaches analysed. While within each community, the same terms are ambiguously used to refer to more than one assessment approach, the confusion is enhanced between the two communities by using different labels for very similar approaches. As an application of the results, similarities and differences between two assessment tools are analysed: the Dynamic Interactive Vulnerability Assessment model (DIVA) for the case of vulnerability to climate change and the CATastrophe SIMulation model (CatSim) for risk of natural hazards.     

Population vulnerability assessment based on scenario simulation of rainstorm-induced waterlogging: a case study of Xuhui District, Shanghai City

Waterlogging is one of the most serious hazards in cities. People are the core of the human social system and the main group affected by disasters. This research introduces a method of scenario simulation which provides a basis for the accurate measurement of exposure to waterlogging. Then based on the concept and structure of vulnerability, representative indicators are selected to develop an indicator system based on objective weights derived from principal components analysis. The method is then used to conduct a population vulnerability assessment in Xuhui District of Shanghai city based on scenario simulation of rainstorm-induced waterlogging over a 50-year period. The final assessment results show that the population vulnerability is greatest for Tianlin Street, Lingyun Street, Changqiao Street, Fenglin Street, and Caohejing Street, while Tianping Street, Xujiahui Street, and Xietulu Street have medium levels of vulnerability. Hongmei Road Street, Healthy Village Street, Longhua Street, and Hunan Road Street have low levels of vulnerability, and Huajing Town is the area with the lowest population vulnerability. The results provide both necessary information and guidance for the government to improve the flood management.     

Social vulnerability to natural hazards in Indonesia: driving factors and policy implications

Indonesia is located in the Pacific Ring of Fire and situated at the joining point of four major world tectonic plates. Regions of Indonesia are highly prone to various natural hazards such as earthquakes, tsunamis and volcanic eruptions. Some recent major natural hazard events are the 2004 tsunami in Aceh and Nias and the 2010 Mount Merapi volcanic eruptions in Central Java. In parallel with advancement in knowledge of the existing hazards, the importance of social aspects of vulnerability in mitigating natural hazards has been acknowledged by the Indonesian government. However, to date, there is no institutionalized effort for assessing social vulnerability to natural hazards that would cover all the districts of Indonesia. Accordingly, no comprehensive profile of social vulnerability is available as basis information for developing strategies to prevent larger risk and losses and reduce vulnerability of communities in Indonesia. Only a few studies have been conducted in Indonesia on this field. This study attempts to fill this gap by quantifying the social vulnerability of Indonesian districts to natural hazards, determining its driving factors and mapping its variations. The social vulnerability index (SoVI) approach is utilized in this study. Three main driving factors affecting social vulnerability in Indonesia are found: ‘socioeconomic status and infrastructure,’ ‘gender, age and population growth’ and ‘family structure.’ The combination of SoVI with thematic map utilizing ArcView GIS can be used to identify districts with relative high social vulnerability level. The results can support the prevention, mitigation, preparedness, response and recovery programs of the impacts of natural hazards in Indonesia.     

城市山洪灾害易损性的RS和GIS分析

以受山洪灾害影响突出的云南文山城区为研究区,从承灾体属性特征和社会承灾能力二个方面探讨了城市山洪灾害易损性分析的方法;利用高分辨率遥感卫星影像为数据源完成城市土地覆盖类型解译,在此基础上应用GIS定量分析城市山洪灾害易损性。对承灾体属性特征定量分析结果表明,文山城区50年一遇山洪淹没范围内的承灾体中城市房屋建筑的易损性最大。对易损性要素中的社会承灾能力分析认为,由于文山城区段防洪河道行洪能力低,蓄滞洪能力弱。山洪灾害的易损性仍然较高,山洪对文山城威胁形势严峻。     

Regional vulnerability assessment for debris flows in China—a CWS approach

Based on former conceptual models of vulnerability, this paper aims to improve the quantitative model for regional vulnerability assessment by analyzing in-depth the relation between vulnerability, exposure, coping capacity, and resilience. Taking the mountain settlements in the upper reaches of Min River, China, as a case study, the method of Contributing Weight Superposition (CWS) is applied in establishing both a model and a system for the vulnerability assessment of elements at risk. The CWS approach consists of 13 index factors including population, economic and road densities, building and farmland coverage, hazard-affected areas, urbanization rate, and GDP per capita. Accordingly, a debris flow hazard vulnerability zoning map was obtained and the assessment results show that the distribution of high and comparatively high vulnerability zones, where economic activities are considerably high, has a close correlation to the topography of the catchment and population characteristics. The results thus may serve as a pertinent guidance for settlement relocation, population distribution readjustment, and management to prevent and reduce hazards in the upper reaches of Min River and beyond.     

A multi-criteria evaluation model of earthquake vulnerability in Victoria,British Columbia

Researchers have recently examined the geographic variability of the vulnerability of populations to earthquakes. These studies focus mainly on the complex modelling of geophysical processes or identification of socio-economically disadvantaged populations. However, no studies to date have integrated different components of vulnerability with metrics of travel distance to hospitals and trauma centres (systemic vulnerability). We argue that this previously unaccounted component is an important conceptual and practical aspect of earthquake vulnerability. Accordingly, this paper presents a multi-criteria model for combining physical, social, and systemic components, moving towards a more comprehensive assessment of vulnerability. An analytic hierarchy process is used to produce a place-specific index of social vulnerability, which we combine with soil liquefaction and amplification index and a road network model for access to hospitals and trauma services. Using a geographic information system, we implemented this model for the Greater Victoria region (483 km², 2011 population: 345,000) in British Columbia, Canada. Clustering of total vulnerability was found in outlying areas, highlighting the importance of access to trauma centres. We conclude by identifying challenges in measuring earthquake vulnerability and advocate integration of systemic vulnerability components in natural hazards research.     

区域泥石流灾害的定量风险分析

概述了区域泥石流灾害的风险分析体系,指出了过去区域泥石流灾害危险性研究中的某些误区以及区域社会经济易损性评价的难点。借助于“灾害熵”的概念,提出了区域泥石流灾害危险性定量分析的一种新方法。通过将泥石流灾害的危险性和区域社会经济易损性进行分级,建立了风险评价矩阵。在此基础上,对区域泥石流灾害的风险进行了分级,可为有效地进行区域泥石流灾害的预警,以及为减灾防灾奠定了坚实的基础。     

Understanding the vulnerability of migrants in Shanghai to typhoons

China has experienced considerable migration from inland to coastal areas since the reforms of 1978, with migrants becoming an important population in many coastal cities. Compared with non-migrants (long-term residents), migrant vulnerability to typhoons is considered high due to limited access to job opportunities, social security, information, and other resources; however, there is no research on vulnerability of this population sector to natural hazards. This initial study analysed the perceptions and personal experiences of migrants living in Shanghai of typhoon hazards. During May 2010, empirical data were collected using an online questionnaire and face–face interviews. Response data indicated that risk knowledge of migrants was significantly lower than among non- migrants; differing risk perceptions between the groups were consistent with levels of personal typhoon experience; statistically significant differences in hazard knowledge within the sample also related to education and occupation; a variety of strategies to cope with typhoon hazards was being applied by residential committees; and that migrants were not generally recognised as a vulnerable group requiring special consideration in hazard risk management. To reduce the vulnerability of migrants to typhoons, we recommend expanding the range of accessible communication technologies distributing warning information; organising more educational and training programmes, at government and corporate level, to increase community awareness of natural hazards; encouraging local residential committees to promote social networks and engagement for migrants; and providing corporate incentives to develop insurances specifically for migrant needs. Further research is necessary to assess the differences in vulnerability between different types of migrants.     

Investigation of ionospheric TEC precursors related to the M7.8 Nepal and M8.3 Chile earthquakes in 2015 based on spectral and statistical analysis

The assessment of social vulnerability is a requirement for understanding the risk of natural hazards. This paper calculates the social vulnerability index of geological disasters in China with the super-efficiency DEA (data envelopment analysis) model, carries out global and local autocorrelation tests for social vulnerability to geological disasters in each province in China and identifies the characteristics of its spatial distribution pattern. The results show the following. (1) China’s social vulnerability to geological disasters is relatively high and has obvious differences. It represents the pattern of a significant increase by degrees in social vulnerability to geological disasters from east to west and a significantly negative correlation relationship between the vulnerability level and the economic level. (2) Based on the comparative analysis of the mean values of the indexes and the social vulnerability index of geological disasters, it is found that the social vulnerability index of geological disasters in China is directly related to the regional exposure degree and reaction and recovery ability, among which the reaction and recovery ability has great effects on the social vulnerability index. (3) Most of the regions in China are in a high–high clustering area or a low–low clustering area; that is to say, the regions with similar social vulnerability to geological disasters represent the pattern of clustering.     

安徽阜阳中心城区地面沉降灾害风险评价

阜阳市作为地面沉降的典型城市,近年来,地面沉降已成为阻碍城市发展的重要地质环境问题。研究结合阜阳市现行地质条件,从地面沉降现状、自然因素与人类活动三个方面建立适用于阜阳市的地面沉降危险性评价指标体系,从地面高程、人口密度、单位面积GDP、工程重要性分布4个方面建立易损性评价指标体系共同组建风险性评价指标体系,引入层次分析法-综合指数法完成阜阳市地面沉降风险评价。依据评价结果提出针对性防控建议,取得的研究成果可为阜阳市国土空间开发规划与社会经济发展提供地学依据。     

自然灾害脆弱性曲线研究进展

在全球变化与全球化背景下自然灾害风险逐年增大,灾害评估就成为风险防范的重要基础。灾害评估包括灾情估算与风险评估2个方面,而脆弱性分析是把灾害与风险研究紧密联系起来的重要桥梁。脆弱性曲线作为定量精确评估承灾体脆弱性的方法,近年来在多领域被广泛运用,成为灾情估算、风险定量分析以及风险地图编制的关键环节。从致灾因子角度综述脆弱性曲线的研究进展,重点阐述基于灾情数据、已有曲线、调查和模型的脆弱性曲线构建。研究表明脆弱性曲线构建由单曲线向多曲线库、单一参数向综合参数、单一方法向多领域综合应用发展,具有综合化和精细化的趋势。进一步开展多领域、多方法综合脆弱性曲线研究,对灾损快速评估及风险评价,防灾减灾具有重要意义。     

四川康定城地质灾害社会经济易损性分区评价

以康定城为例提出了城市地质灾害社会经济易损性分区评价的新方法,建立了地质灾害社会经济易损性评价方法体系。在对评价因子充分论证的基础上,分别对康定城2005年和2020年的地质灾害社会经济易损性进行了分区评价,评价结果可为康定城市地质灾害危险区的划定提供依据。     

澜沧江流域重大水电工程扰动灾害风险评价

地质灾害风险性评价对当地防灾减灾具有指导意义。本文以澜沧江重大水电工程扰动灾害为例,在遥感解译与野外实际调查的基础上,选取高程、坡度、坡向、植被归一化指数、距库区距离、工程地质岩组、断裂带密度、年均降雨量、地震峰值加速度9个因素,并基于加权信息量模型进行危险性评价,然后以人口密度、水电站、道路、土地覆盖类型和GDP为承灾体进行易损性评价,最后将危险性和易损性进行信息融合,构建地质灾害风险性矩阵,完成地质灾害风险性评价。评价结果表明：极高和高风险区主要分布在乌弄龙及其上游水电站附近,以及下游库区两岸人类活动相对密集区域,中风险区主要分布在乌弄龙上游库区两岸以及乌弄龙—托巴水电站全域,在下游零散分布;低风险区主要分布在中游高山峡谷段。本次研究较为准确地评估了地质灾害风险性,可为澜沧江流域扰动地质灾害风险规划提供科学依据和技术指导。     

三峡库区地质灾害易损性模糊综合评价

地质灾害是灾害危险性对承灾体易损性综合作用的结果,减灾应从减少地质灾害的发生频率和降低其易损性入手,限于目前的科学水平,人们难以改变地质灾害的发生过程,那么降低地质灾害易损性就成为减灾的重要措施,因此进行灾害易损性评价就显得尤为重要。本文以三峡库区为研究区,选取人口密度、国内生产总值密度等指标,运用模糊综合评判对其进行了定量评估。由于各指标因子在地质灾害易损性中的作用具有模糊性,因此运用模糊模型进行评价具有一定的意义。将库区地质灾害易损性程度划分为4个等级,研究结果表明,三峡库区地质灾害易损性程度总体较高。易损度较高的地区应强化减灾意识、调整人口结构以及加大防灾投入,以降低本地区的地质灾害易损性。