Flood risk perceptions and spatial multi-criteria analysis: an exploratory research for hazard mitigation

The conventional method of risk analysis (with risk as a product of probability and consequences) does not allow for a pluralistic approach that includes the various risk perceptions of stakeholders or lay people within a given social system. This article introduces a methodology that combines the virtues of three different methods: the quantifiable conventional approach to risk; the taxonomic analysis of perceived risk; and the analytical framework of a spatial multi-criteria analysis. This combination of methods is applied to the case study ‘Ebro Delta’ in Spain as part of the European sixth framework project ‘Floodsite’. First, a typology for flood hazards is developed based on individual and/or stakeholders’ judgements. Awareness, worry and preparedness are the three characteristics that typify a community to reflect various levels of ignorance, perceived security, perceived control or desired risk reduction. Applying ‘worry’ as the central characteristic, a trade-off is hypothesized between Worry and the benefits groups in society receive from a risky situation. Second, this trade-off is applied in Spatial Multi-Criteria Analysis (SMCA). MCA is the vehicle that often accompanies participatory processes, where governmental bodies have to decide on issues in which local stakeholders have a say. By using risk perception-scores as weights in a standard MCA procedure a new decision framework for risk assessment is developed. Finally, the case of sea-level rise in the Ebro Delta in Spain serves as an illustration of the applied methodology. Risk perception information has been collected with help of an on-site survey. Risk perception enters the multi-criteria analysis as complementary weights for the criteria risk and benefit. The results of the survey are applied to a set of scenarios representing both sea-level rise and land subsidence for a time span of 50 years. Land use alternatives have been presented to stakeholders in order to provide the regional decision maker with societal preferences for handling risk. Even with limited resources a characteristic ‘risk profile’ could be drawn that enables the decision maker to develop a suitable land use policy.     

Seismic hazard assessment and mitigation in India: an overview

The Indian subcontinent is characterized by various tectonic units viz., Himalayan collision zone in North, Indo-Burmese arc in north-east, failed rift zones in its interior in Peninsular Indian shield and Andaman Sumatra trench in south-east Indian Territory. During the last about 100 years, the country has witnessed four great and several major earthquakes. Soon after the occurrence of the first great earthquake, the Shillong earthquake (M _w: 8.1) in 1897, efforts were started to assess the seismic hazard in the country. The first such attempt was made by Geological Survey of India in 1898 and since then considerable progress has been made. The current seismic zonation map prepared and published by Bureau of Indian Standards, broadly places seismic risk in different parts of the country in four major zones. However, this map is not sufficient for the assessment of area-specific seismic risks, necessitating detailed seismic zoning, that is, microzonation for earthquake disaster mitigation and management. Recently, seismic microzonation studies are being introduced in India, and the first level seismic microzonation has already been completed for selected urban centres including, Jabalpur, Guwahati, Delhi, Bangalore, Ahmadabad, Dehradun, etc. The maps prepared for these cities are being further refined on larger scales as per the requirements, and a plan has also been firmed up for taking up microzonation of 30 selected cities, which lie in seismic zones V and IV and have a population density of half a million. The paper highlights the efforts made in India so far towards seismic hazard assessment as well as the future road map for such studies.     

Infrastructure hazard resilience trends: an analysis of 25 years of research

Hazard research has made significant strides over the last several decades, answering critical questions surrounding vulnerability and recovery. Recently, resilience has come to the forefront of scholarly debates and practitioner strategies, yet there remain challenges implementing resilience in practice, the result of a complex web of research that spread across numerous fields of study. As a result, there is a need to analyze and reflect on the current state of resilience literature. We reviewed 241 journal articles from the Web of Science and Engineering Village databases from 1990 to 2015 to analyze research trends in geographic location of studies, methods employed, units of analysis, and resilience dimensions studied, as well as correlations between each of these categories. The majority of the studies analyzed were conducted in North America, used quantitative methods, focused on infrastructure and community units of analysis, and studied governance, infrastructure, and economic dimensions of resilience. This analysis points to the need to: (1) conduct studies in developing country contexts, where resilience is particularly important; (2) employ mixed-methods for additional depth to quantitative studies; (3) connect units of analysis, such as infrastructure and community; and (4) expand on the measurement and study of environmental and social dimensions of resilience.     

Correction to: A historical geomorphological approach to flood hazard management along the shore of an alpine lake (northern Italy)

Natural Hazards - This correction stands to correct mistakes presented in the original article due to a lag in the e-proofing system and the correction handling for this article. The original...     

2010-2016年国际极地研究综合评价分析

极地在气候系统、全球资源和战略中具有重要意义,并且随着人类对它的开发,极地研究也日益成为地球与环境科学领域的核心和热点议题。基于Web of Science数据库收录的2010-2016年SCI文章,利用文献计量方法,结合国际政策和战略,分析了2010-2016年极地研究的发展格局和变化趋势。结果表明：（1）近年来国际极地研究论文年发文量总体呈持续增长态势,年均增幅为3.6%。（2）发达国家及高纬度国家是极地领域的主要研究力量,美国占据绝对优势。（3）在SCI发表的国际极地研究论文来源期刊共计915种,来自57个国家,美国期刊占1/3。（4）结合欧盟极地研究优先领域和文献计量方法得出,极地研究未来新的发展方向侧重于人文及社会因素,重点提倡人类对极地的影响以及新技术应用。建议我国科研人员密切关注国际极地研究的发展态势和进展,鼓励海洋学、气象学、地质学、环境生态学、生物学、社会学和政治学等领域专家有计划地开展极地研究,为我国赢取极地研究国际发言权和参与度。     

A historical geomorphological approach to flood hazard management along the shore of an alpine lake (northern Italy)

A project to develop a flood hazard management plan along the east shore of Lago Maggiore was carried out. Several municipal territories along a coastal stretch have been analysed, identifying the rate of water rise and the limits of the submerged areas. This study discusses the overall methodological approach and presents the results for Porto Valtravaglia, as a significant case study. The first step was a detailed analysis of historical events to locate the most frequently damaged sites. Thousands of historical documents on past floods were collected, selected and validated, to map the most vulnerable sites. The second step was a morphological analysis of the studied coastal stretch. Multi-temporal aerial snap-shots were used and field surveys were conducted to verify the reliability of the historical data and to identify the critical hydraulic conditions along the shore. The third step was a review of the general urban development plans of the 17 studied municipalities. Aerophotogrammetric and cadastral maps were used to evidence and define the eight classes of land use destinations. In addition, the floodable areas were divided into three vulnerability and exposure categories considering different peculiarities of social and working life. Finally, using GIS spatial analysis tools, these data were compiled into risk maps and wielded as the municipal emergency plans’ baseline scenarios. For each studied municipality was hypothesised the alarm thresholds upon which were activated the flood emergency procedures.

     

The response of farmers to the drought hazard in the Karoo environment

The response of farmers to the drought hazard in the Karoo environment. This paper identifies the range of farmers' responses to the drought hazard and seeks to determine whether they are successful in reducing the detrimental effects of drought. Farmers' responses to a survey are analysed within the framework of six response types namely: affecting the cause, modifying the hazard, modifying the loss potential, spreading the losses, planning for losses and bearing the losses. The success of farmers' responses is evaluated individually and cumulatively in terms of their being able to minimize a reduction in farmers' income as a result of drought. Various characteristics of the farmers and their farming enterprise are also examined in relation to the success of measures to mitigate the adverse effects of drought. A major finding is that no specific actions are able to adequately protect them from the detrimental effects of a major drought.     

寒冷地区输水渠道冻胀破坏链式分析及减灾研究

寒冷地区输水渠道在运行过程中,由于持续负温的影响,地温逐步下降,引起渠基土体水分分布发生变化导致土体冻胀,致使输水渠道结构破坏,这种作用影响所表现出来的链式效应是冻胀破坏作用的重要特征。为了探明寒冷地区输水渠道冻胀破坏机理,分析渠道的冻胀破坏因素,引入链式破坏理论进行分析。从系统理论出发,分析冻胀破坏系统的链式关系结构,建立冻胀破坏链式效应关系模型。以寒冷地区渠道衬砌结构冻胀破坏为例,分析经过一个冻融周期,渠基土体颗粒、土体成分组成、气温、地温变化规律和土壤水分迁移规律对渠道衬砌结构冻胀破坏的影响。分析渠道衬砌结构冻胀破坏链式机理,是在外部环境气温、水分等条件输入下,地温分布受土体性质及土体水分的影响,土体水分迁移受地温和土体性质的作用,土体产生冻胀是对地温和水分分布作用的响应,以此为依据提出寒区渠道冻胀破坏断链减灾方法。     

Characteristics and mitigation of the snow avalanche hazard in Kaghan Valley,Pakistan Himalaya

Snow avalanche hazards in mountainous areas of developing countries have received scant attention in the scientific literature. The purpose of this paper is to describe this hazard and mitigative measures in Kaghan Valley, Pakistan Himalaya, and to review alternatives for future reduction of this hazard. Snow avalanches have long posed a hazard and risk to indigenous populations of the Himalaya and Trans-Himalaya mountains. Land use intensification due to population growth, new transportation routes, military activity and tourism is raising levels of risk. The history of land use in the study area is such that investigations of avalanche hazard must rely on different theoretical bases and data than in most industrialised countries. Despite the intensive use of valley-bottom land which is affected by avalanches, a number of simple measures are currently employed by the indigenous population to mitigate the hazard. Out-migration during the winter months is the most important one. During the intensive use period of summer avalanche-transported snow provides numerous resources for the population. In Kaghan the avalanche hazard is increasing primarily as a result of poorly located new buildings and other construction projects. The large scale of avalanche activity there rules out any significant improvement or protection of the currently difficult winter access. Instead, future mitigation of the hazard should focus on protecting the small number of winter inhabitants and minimising property damage.     

Flood hazard in Hunan province of China: an economic loss analysis

Natural and man-made disasters have been increasing and affecting millions of people throughout the world. Floods are the most common natural disasters affecting more people across the globe than all other natural or technological disasters and also are the most costly in terms of human hardship and economic loss. In order to explore the total economic loss, components of economic loss, and factors influencing economic loss during flooding, a retrospective study was carried out in year 2000 in areas that suffered floods in 1998 in Hunan province, China. A total of 10,722 families were investigated using a multistage sampling method. We found that the total economic loss to the 10,722 families investigated was US$ 8.925 million; translating into an average economic loss of US$ 832.45 per family and US$ 216.75 per person. Economic loss related to property loss, income loss, and increased medical cost accounted for 57.38%, 40.00%, and 2.62% of the total economic loss, respectively. Economic loss was significantly related to a family’s pre-flood income; duration of the flood; severity of flood; and type of flood. River floods yielded the highest economic loss and drainage problem floods yielded the lowest loss. We recommended that flood-related preventive measures should focus on the prevention of river floods and shortening the duration of floods with the view of significantly minimizing economic losses associated with floods.     

花山谜窟景区2号、35号洞窟稳定性分析研究

花山谜窟景区2号、35号洞窟位于安徽省黄山市的新安江畔,其所处的地质环境条件复杂,洞窟区岩石力学的强度差异大,洞窟顶板裂隙较发育,顶板渗水较严重,加之,洞窟内部分支撑柱的间距过大,洞窟开发过程中忽略了对洞窟地质环境的保护等,引发了片状剥落、块状坠落、新生裂缝(顶板及支撑柱)三类洞窟变形失稳问题,这三类问题不仅破坏了洞窟内的地质环境,同时,也给洞窟的科学保护带来了隐患。为此,对洞窟稳定性问题产生的条件进行分析研究,并在此基础上提出了加强洞窟地质环境保护的对策。     

Logistic Regression analysis in the evaluation of mass movements susceptibility: The Aspromonte case study,Calabria, Italy

This work describes the application of Logistic Regression (LR) to an assessment of susceptibility to mass movements in a 850 km² study area mainly on the Ionian side of the Aspromonte Range, in southern Calabria.LR is a multivariate function that can be utilised, on the basis of a given set of variables, to calculate the probability that a particular phenomenon (for instance, a landslide) is present. In the present study the set of relevant variables includes: rock type, land use, elevation, slope angle, aspect, slope profile curvature down-slope and across-slope.The aim of this paper is to evaluate the LR performance when the procedure is based on the surveying of mass movements in part of the study area. The procedure adopted was GIS-based, with a 10 m DEM square-grid; for slope and curvature calculation, four adjacent cells were grouped to form a nine-point set for mathematical processing.The LR application consists of four steps: sampling, where all relevant characteristics in a part of the area (ca. 27% of the study zone) are assessed; variable parameterisation, where non-parametric variables are transformed into parametric (or semi-parametric) variables (on at least rank scale); model fitting, where regression coefficients are iteratively calculated in the sample area; model application, where the best-fit regression function is applied to the entire study area. This procedure was applied in two ways: first considering all types, then a single type of mass movement.The ground characteristics of the whole study zone were determined. The LR procedure was first tested by extending the sampling and reclassification steps to the whole study zone to find out the best possible fitting regression; the results of this were then compared with ground truth to maximise performance. Afterwards, the results of LR analysis, based on extension of regression formulas obtained also using 40% sampling zones, were compared with those of the best possible one and ground truth. Comparisons were performed by means of a confusion matrix and a simple correlation between expected vs. observed values for grouped variables. The overall results seem promising: for example, if the 27% sample areas are adopted, 94% of the cells where the probability of the existence of any kind of mass movements is between 85.5% and 95%, are actually affected by mass movements. Results are instead less good when attempting to distinguish between types of mass movement.     

On the 40th anniversary of the zvenigorod training practicum for field methods of engineering-geological,hydrogeological, geocryological,engineering-geophysical,and ecological-geological investigations

A brief history of training practicums at Zvenigorod is characterized according to its current state and organization, curriculum, teaching and field equipment, and everyday conditions. Each year in June from 45 to 75 students of the Faculty of Geology practice at the Biological Research Station of MSU. In the 40 years of this practicum, more than 2000 students of the Faculty of Geology of Moscow State University have attended the practicum.     

遥感技术在地质灾害调查及灾害规律研究中的应用——以辽宁省建昌县为例

地质灾害与地质环境条件、人类工程活动关系密切,严重威胁着人类生命财产安全,制约社会经济的可持续发展。运用遥感技术对辽宁省建昌县进行地质灾害调查,利用ENVI5.3软件对高分二号数据进行预处理,建立遥感解译标志并开展了野外验证,最终解译滑坡、崩塌、泥石流、地面塌陷等地质灾害点75个;同时,利用Arcgis10.4空间分析功能,对遥感解译地质灾害点与地貌、坡度、坡向、构造、水系及人类工程活动等因子进行叠加分析,基本查清了研究区地质灾害规模、空间分布特征和发育规律,为研究总结区域上地质灾规律及有效预防提供了详实可靠的基础资料。