地下水脆弱性和风险性评价研究进展综述

地下水脆弱性和风险性评价与区划是区域地下水资源保护的重要依据。本文回顾了各国地下水脆弱性评价与编图研究工作以及地下水污染风险评价研究的最新进展,提出地下水污染风险评价的框架及其指标体系,最后指出今后需要深入研究的问题。     

基于承灾体易损性的县域单元地质灾害风险评估

县域单元的地质灾害风险评估是宏观层面资源环境承载能力监测预警的重要组成部分,可以作为行政单元生态文明建设考核的依据,对国土空间规划编制也具有重要的参考价值。针对承灾体易损性定量评价这一难点,尝试改进笔者以前的评估方法,以地质灾害易发区内的人口和资产作为承灾体统计,并根据省级单元地质灾害调查数据进行校正;以原国土资源部权威灾情数据与承灾体的比值作为易损性,依据全国样本值进行了承灾体易损性分级标准划定,结合地质灾害危险性区划完成全国2869个县域单元的地质灾害风险评估。结果表明,全国共有162个地质灾害高风险单元,701个中风险单元和2006个低风险单元。地质灾害高风险区集中分布于横断山区、乌蒙山区、秦岭—大巴山区、长白山区等地。     

基于GIS的地下水易污性评价系统

介绍了基于MapGIS开发的地下水易污性DRAMTICH评价系统,说明地下水易污性评价软件(GW-VAS)的基本框架、主要功能、组成部分、系统特点以及使用方法。该系统还对DRASTIC等其它常见的地下水易污性评价方法进行了综合集成,克服了单一方法缺乏对比性的不足,提高了评价结果的客观性、科学性和实用性。并将该方法应用于黄水河流域,利用传统的权重评分法和本文开发的方法进行了对比,结果表明,系统通用性好,方法实用性强。 更多还原     

Overwash vulnerability assessment based on long-term washover evolution

An integrated methodology for evaluation of overwash vulnerability is developed with respect to the historical washover evolution of a barrier island system. Three different aspects of overwash are addressed in the vulnerability indices developed: overwashed shoreline ratio, maximum overwash intrusion recurrence, and complete barrier overwash. The indices were applied to the barriers in the Ria Formosa system in Southern Portugal using an aerial photography catalogue covering the period 1947–2001. Historical trends of washover evolution were observed to be different between the barriers analysed, but generally, there was a decrease in washover number and dimensions throughout the analysed period. The final overwash diagnostic obtained allowed an integrated overwash vulnerability rating to be defined for each barrier, with vulnerabilities ranging from low to extreme. The methodology has produced results that may assist coastal managers with information concerning barrier island system overwash hazard, define the temporal and geographical distributions of overwash, and provide indications as to where overwash is most likely to occur in the future.     

Implementation of an integrated vulnerability and risk assessment model

An integrated vulnerability and risk assessment model (IVR) is proposed. The proposed model is a composite index that assesses the relationships among four critical components, namely exposure, hazard, vulnerability and capacities and measures, and how these can be used to illustrate the integrated risk and vulnerability situation of an area. These factors are assessed using individual variables. Fifty-four variables, objectively decided upon, were used to measure the contribution of each component factor. The general characteristics of vulnerability, risk, exposure and capacities and measures are well known; however, the relative importance of each variable and their inter-relatedness, in measuring risk and vulnerabilities, as demonstrated by the IVR; and how these in turn affect the impacts of natural hazards, are still debatable. The IVR though provides a valid, reliable and sensitive tool, which can be used to further explore these relationships. Through robust testing and application, subjectivity in the selection of variables can be reduced. Moreover, through the establishment of a database for data collection and storage, objectivity (reliability) can be achieved as well as, availability of the requisite data inputs. The sensitivity of the model allows for the quick identification of strategic action, which will ultimately lead to hazard loss reduction. The values yielded for each component factor can help decision-makers in the allocation of scarce developmental funds as well as identify trends in levels of risk, vulnerability, exposures and capacities and measures as well as determine areas where mitigation strategies are needed most.     

Analysis of the global tsunami data for vulnerability and risk assessment

For the assessment of tsunami risk and vulnerability, one has to make use of past tsunami observations. The most comprehensive tsunami databases for the world have been prepared by the National Geophysical Data Center of USA which are listed on their website for all the four oceans as well as the following marginal seas: Caribbean Sea, Mediterranean Sea, Black Sea, Red Sea and Gulf of Mexico. The dataset goes back as far as the first century AD and lists the events on a confidence rating scale of 0–4; 0 being an erroneous entry and 4 being a definite tsunami. Based on these various datasets for different geographical areas, a comprehensive global dataset was prepared in this study, which included only tsunami events with confidence rating of 3 and 4, meaning either probable or definite. In this composite and abridged global tsunami database there is no distinction either according to geography or tsunami strength as implied by its impact on the coast. A simple and straightforward statistical analysis suggests an almost complete randomness and no patterns that can be used for future tsunami predictions with a few minor exceptions.     

基于DRASTIC的含水层脆弱性模糊评价方法与应用

通过分析目前广泛采用的DRASTIC方法存在的主要问题,将含水层脆弱性定义为模糊概念,结合模糊分析评价理论及三标度分两步的层次分析法建立了一套改进的含水层脆弱性评价模型。为测试其可靠性,分别将改进模型和传统DRASTIC模型应用于祁县东观镇含水层脆弱性评价中。研究结果表明:改进模型得到的脆弱性等级变化较后者更灵敏,分布范围及变化情况更精确,更能真实反映含水层脆弱性在空间上的连续变化,且计算简便、脆弱性分区图效果直观,丰富和完善了地下水脆弱性评价方法。     

Rethinking the relationships of vulnerability, resilience, and adaptation from a disaster risk perspective

Vulnerability, resilience, and adaptation are three fundamentally inter-related concepts among such research communities as global environmental/climatic change, social–ecological and disaster risk science. However, their mutual relationships are still unclear so far particularly in the field of disaster risk reduction, which to some extent blocks the reasonable risk analysis and scientific decision making. This paper performed a brief overview on the basic definitions and evolution processes of vulnerability, resilience, and adaptation, and tentatively categorized past diverse thoughts of their relationships into three modalities, such as, vulnerability preference, resilience preference, and overlapped relationships. From a “hit-damage-recovery-learning cycle” insight and based on an empirical case study, we put forward two conceptual frameworks to address the relationships of vulnerability, resilience, and adaptation within the disaster risk domain, and we further discussed their broader implications in terms of disaster risk management and social–ecological sustainability. In an attempt to bring together the analytical frameworks of vulnerability, resilience, and adaptation, this study indicates that a sustainable adaptation strategy to the unavoidable disasters or changes should not only seek to reduce the vulnerability of a social–ecological system, but also to foster its resilience and adaptive capacity to future uncertainties and potential risks.     

A fast GIS-based risk assessment for tephra fallout: the example of Cotopaxi volcano, Ecuador-Part II: vulnerability and risk assessment

In order to develop efficient strategies for risk mitigation and emergency management, planners require the assessment of both the expected hazard (frequency and magnitude) and the vulnerability of exposed elements. This paper presents a GIS-based methodology to produce qualitative to semi-qualitative thematic risk assessments for tephra fallout around explosive volcanoes, designed to operate with datasets of variable precision and resolution depending on data availability. Due to the constant increase in population density around volcanoes and to the wide dispersal of tephra from volcanic plumes, a large range of threats, such as roof collapses, damage to crops, blockage of vital lifelines and health problems, concern even remote communities. To address these issues, we have assessed the vulnerability and the risk levels for five themes relevant to tephra fallout: (1) social, (2) economic, (3) environmental, (4) physical and (5) territorial. Risk and vulnerability indices for each theme are averaged to the fourth level of administrative unit (parroquia, parish). In a companion paper, Biass and Bonadonna (this volume) present a probabilistic hazard assessment for tephra fallout at Cotopaxi volcano (Ecuador) using the advection-diffusion model TEPHRA2, which is based on field investigations and a global eruption database (Global Volcanism Program, GVP). The scope of this paper is to present a new approach to risk assessment specifically designed for tephra fallout, based on a comprehensive hazard assessment of Cotopaxi volcano. Our results show that an eruption of moderate magnitude (i.e. VEI 4) would result in the possible collapse of ??9,000 houses in the two parishes located close to the volcano. Our study also reveals a high risk on agriculture, closely linked to the economic sector, and a possible accessibility problem in case of an eruption of any size, as tephra is likely to affect the only major road running from Quito to Latacunga (Panamerican Highway). As a result, this method fits into the ongoing effort to better characterize and evaluate volcanic risk, and more specifically the risk associated with tephra fallout. Although this methodology relies on some assumptions, it can serve as a rapid and efficient starting point for further investigations of the risk level around explosive volcanoes.     

Waterlogging and flood hazards vulnerability and risk assessment in Indo Gangetic plain

The recurrent flooding during monsoon and subsequent waterlogging in the northern Bihar plains and the magnitude of losses due to these hazards indicate the continuing vulnerability of the region to flood and waterlogging. Management of floods and waterlogging hazards in highly flood-prone regions of India, including Bihar state has been largely response oriented with little or no attention to mitigation and preparedness. This paper presents a method for spatial, Geographic Information Systems-based assessment of flood and waterlogging vulnerability and risk in northern Bihar plains. Multitemporal satellite data was used to evaluate the area statistics and dynamics of waterlogging over the period from 1975 to 2008. The flood proneness is evaluated at district level with reference to flood inundation during a period from 1998 to 2008. Census data were used to examine the socio-economic characteristics of the region through computation of population density, cultivators, agricultural labourers, sex ratio, children in age group 0–6 years and literates. The geohazard map derived by combining area prone to waterlogging and flood inundation was multiplied with socio-economic vulnerability map to derive the flood-waterlogging risk map of the region. The result shows that flood and water-logging pose highest risk to the central districts in the northern Bihar plains with 50.95% of the total area under high and very high risk.     

基于模糊数学的地质灾害危险性评价

陕西省引汉济渭工程跨越秦岭构造剥蚀山地和断陷盆地,地质环境条件差,发育地质灾害点72处。选取地质环境条件、地质灾害发育现状和地质灾害预测为评价指标,分别赋予隶属度值;将工程剖分为284个评价单元,采用模糊数学综合评判法计算每个单元的隶属度值,确定危险性小的单元255个,危险性中等的单元29个;说明工程主要位于危险性小的区段。     

Social vulnerability assessment for mitigation of local earthquake risk in Los Angeles County

Comprehensive hazard mitigation involves (1) understanding natural systems, (2) assessment of interactions within and between social systems and the built environment, and (3) understanding geo-spatial processes. To achieve this, local emergency managers must recognize variability in vulnerable populations exposed to hazards and develop place-based emergency plans accordingly. In this study, we assess whether cities in Los Angeles County are subject to disproportionally greater earthquake losses modeled from a M7.8 earthquake on the San Andreas fault. Furthermore, we analyze whether the variation in demographic and socioeconomic characteristics across cities is associated with the earthquake losses. We were able to explain 23.2?% of variance in economic losses by looking at the percentage of minority residents, income, and renter residents in a city [F(3,84)?=?8.47; p?<?.001]. Cities with primarily minority residents had greater economic losses when compared to cities with primarily White residents (b?=?1.01; p?<?.001). When looking at the association between demographic predictors and potential casualty rate, the percentage of Hispanic residents was positively associated with the potential casualty rate. We argue that knowledge of the relationship between earthquake hazard and the demographic characteristics of people in the area at risk is essential to mitigate the local impact from earthquakes. In other words, we apply social vulnerability assessment as part of a comprehensive risk management framework to accelerate recovery after an event. Local policy makers and the private sector can use this approach to gain a better understanding of a city??s social vulnerability and adapt their preparedness efforts accordingly.     

基于随机理论的地下水环境风险评价

针对确定性模型难以描述含水层非均质空间分布的问题,提出基于随机理论的地下水环境风险评价方法。以矩形场地地下水污染风险评价为例,采用蒙特卡罗法生成大量渗透系数随机场,模拟含水层参数各种可能的非均质空间分布,在此基础上建立场地地下水流模型与溶质运移模型,分别计算污染物在地下水中的迁移转化情况。统计大量随机模拟中污染事故发生的频率,当模拟次数足够多时,污染频率收敛于污染概率,污染风险即通过污染概率体现出来。该方法将模型参数设为满足一定分布特征的随机变量,避免了确定性方法得出的武断的评价结果,可为工厂的选址、水源地的选址等工作提供科学指导。     

An assessment of multidimensional flood vulnerability at the provincial scale in China based on the DEA method

China suffers frequent and severe floods. A lot of studies have been done in the field of flood disaster, including flood vulnerability assessment. This paper develops assessment models of multidimensional flood vulnerability based on the data envelopment analysis method and identifies multidimensional flood vulnerability??population, death, agriculture and economy??at the provincial scale in China using flood damage data and socioeconomic statistical data from 2001 to 2010. Based on the characteristics of multidimensional flood vulnerability of each province, some suggestions for flood prevention and mitigation are suggested. The assessment models of multidimensional flood vulnerability are simple and can be used for vulnerability analysis of natural disaster at regional or national levels. The assessment of multidimensional flood vulnerability can provide multifaceted information that contributes to a deeper understanding of the flood vulnerability and provides a scientific base for the policy making and implementation of flood prevention and mitigation designs.     

基于"3S"技术的地质灾害易损性面评价方法研究

易损性评价是地质灾害灾情评估体系中一个非常重要的内容。它揭示了地质灾害基本构成元素之一的承灾体的社会经济属性,对整个地灾灾情评估体系完整性的构建及评价结果的科学性、明确性、统一性表达具有举足轻重的作用。文章以等面积法作为基本手段,根据评价区实际情况算得的离散等积网格作为评价模板。结合“3S”(GIS、RS、GPS)技术,探讨地质灾害易损性面评价的实现方式,旨在提出“3S”框架内的地质灾害灾情评估实现模式。在具体操作层面上,文章提出了为实现易损性面评估而确立的评价对象之层次分类方法、评价模板构造计算方法、空间数据库建设方法、基于空间数据库的空间分析方法以及空间信息集成模型。重点讨论在空间数据完整性基础上的多源数据融合处理模式及以GIS空间分析算法模式为蓝本的空间数据处理和集成手段。在理念层面上,文章将空间分析实现方法分为现实评价区域、概念评价区域、数字评价区域、逻辑映射虚拟区域等4个阶段,认为在GIS环境下的地灾灾情评价原始空间数据、派生空间数据以及经专用模型集成后的结果空间数据的可视化表达方式可以分为颜色序列、数字高程模型(DTM)及等值线3种表达方式。最后提出实现地质灾害易损性面评价的一般操作流程。     

The challenge of peripheral ports: an Asian perspective

The growth of ports peripheral to the dominant container hubs has been well documented in North America and Europe, and has led to the elaboration of several theoretical models. This paper applies these models to the situation in South East Asia where much of the growth in containerisation is taking place. While confirming the emergence of several peripheral ports that are mounting challenges to the major hubs, we demonstrate that the factors behind the challenges are different to those postulated in the literature. Issues of governance arising out of the complex restructuring of the global ports industry are singled out. We suggest that a new geography of container terminals based on management and operational strategies of private and public bodies involved in the port industry needs to be fashioned.     

A methodology for urban micro-scale coastal flood vulnerability and risk assessment and mapping

Natural Hazards - Wind gusts are a major cause of damage to property and the natural environment and a source of noise in seismic networks such as the USArray Transportable Array. Wind gusts cause...