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131.
An earthquake scenario for the microzonation of Sofia and the vulnerability of structures designed by use of the Eurocodes 总被引:3,自引:0,他引:3
Paskaleva Ivanka Dimova Silvia G.F. Panza Giuliano Vaccari Franco 《Soil Dynamics and Earthquake Engineering》2007,27(11):1028-1041
The study of the site effects and the microzonation of a part of the metropolitan Sofia, based on the modelling of seismic ground motion along three cross-sections are performed. Realistic synthetic strong motion waveforms are computed for scenario earthquakes (M=7) applying a hybrid modelling method, based on the modal summation technique and finite differences scheme. The synthesized ground motion time histories are source and site specific. The site amplification is determined in terms of response spectra ratio (RSR). A suite of time histories and quantities of earthquake engineering interest are provided. The results of this study constitute a “database” that describes the ground shaking of the urban area. A case study of experiment-based assessment of vulnerability of a cast-in-situ single storey, industrial, reinforced concrete frame, designed according to Eurocodes 2 and 8 is presented. The main characteristics of damage index and storey drift are discussed for the purposes of microzonation. 相似文献
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An environmental history of the Leliefontein community of Namaqualand, Northern Cape provides a detailed case of the nexus between social and ecological stresses shaping livelihood change. By combining an historical proxy precipitation data set with a livelihood change study the value of historical research in integrated studies of past human-environment systems is illustrated. The identification of effective livelihood adaptation to extreme climatic conditions is examined, illustrating the tradeoffs made between adaptation and ‘coping’ strategies which were unsuccessful over the long term. During the course of the 19th century the Namaqua Khoikhoi population changed from a sustainable nomadic pastoral community to a poverty stricken rural community with a diversity of livelihood strategies. For the Namaqua increased livelihood diversity – usually an effective adaptation in times of stress – instead of promoting resilience, contributed to their material decline. Widespread transhumance between different climatic regions is shown to have been a successful adaptation to climatic extremes, but external economic exposure and restricted access to land become drivers of decline. The ‘double exposure’ framework used in contemporary studies, proved useful in accounting for this decline as it can accommodate both environmental and economic stressors. 相似文献
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在地下水水质现状、地下水污染趋势、含水层固有脆弱性、污染源荷载风险、地下水污染危害性五个要素的基础上建立了地下水污染预警评价指标体系,利用GIS组件开发技术,与地下水污染预警模型相结合,采用VB.NET+Arc GIS和Engine+Access集成的组件式GIS二次开发模式,开发可脱离GIS平台独立运行的地下水污染预警系统。系统可分别进行研究区域的水质评价、水质预测、含水层固有脆弱性评价、污染源荷载风险计算、污染风险评价、污染预警分析。对典型水源地地区地下水环境污染的警度进行识别,对即将可能出现的警情进行预报,并依据警度划分了防护治理区、重点防护区和一般防护区,提出了相应的防治措施,为政府部门制定地下水污染防治规划服务。 相似文献
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Understanding the values and socio-economic characteristics of people at risk from climate change will inform how people feel about the likely distribution of impacts, as well as adaptation responses. This knowledge is necessary if adaptation is to achieve distributive fairness now and into the future. This study advances methods and analyses used in values-based adaptation research by using segmentation to explain the diversity of values that exist within a community, and on this basis identify particular groups at risk. A telephone survey was conducted with residents of Lakes Entrance, Australia—a coastal community already adapting to projected sea-level rise. The purpose was to determine the priorities residents place on a range of lived values—valuations that individuals make about what is important in their lives and the places they live. The telephone survey data was then analysed using cluster analysis to develop a lived values typology of residents. The analysis revealed that there are at least eight types of residents living in Lakes Entrance and that each group of residents has a unique set of lived values that will be differentially affected by sea-level rise and adaptation. The findings indicate that if sea-level rise adaptation policy is to be distributively fair it needs to develop a suite of adaptation responses that ensure that the lived values of each group of residents, and thus a diversity of values, are maintained or enhanced. 相似文献
138.
《Marine Policy》2014
There is increasing concern over the consequences of environmental change for people and communities that depend on already fragile marine resources, given the mounting evidence of sustained over-exploitation and climate change impacts on marine systems. In order to explore the potential social resilience of marine-dependent livelihoods to environmental change, interviews with fishers and marine-based tourism operators in the Caribbean island of Anguilla were undertaken, to identify the impacts of hurricane events on marine livelihoods, the perceptions of resource-users and their potential adaptability to future change. For both sectors of resource-users, there is evidence that they have diversified livelihoods to achieve financial security, which may provide resilience to future climate related impacts or resource variability. In addition, specific behavioural changes that have been developed following previous hurricane events, e.g. removal of fish pots during hurricane months, or bringing boats to shore, indicate fishers' flexibility to changing conditions. However, strong personal and cultural attachment to occupations, particularly among fishers, may hinder resilience. Additionally, the reliance of all of these marine resource-users on the climate-dependent tourism industry may undermine their capacity to cope with future environmental change. Many of these problems are common throughout the Caribbean, as thousands of marine-dependent livelihoods are vulnerable to marine degradation and climate change impacts. Urgent attention is therefore required to support the development of adaptive, sustainable management of marine resources that may enhance resilience to environmental change. 相似文献
139.
Syud Amer Ahmed Noah S. Diffenbaugh Thomas W. Hertel David B. Lobell Navin Ramankutty Ana R. Rios Pedram Rowhani 《Global Environmental Change》2011,21(1):46-55
Climate volatility could change in the future, with important implications for agricultural productivity. For Tanzania, where food production and prices are sensitive to climate, changes in climate volatility could have severe implications for poverty. This study uses climate model projections, statistical crop models, and general equilibrium economic simulations to determine how the vulnerability of Tanzania's population to impoverishment by climate variability could change between the late 20th Century and the early 21st Century. Under current climate volatility, there is potential for a range of possible poverty outcomes, although in the most extreme of circumstances, poverty could increase by as many as 650,000 people due to an extreme interannual decline in grain yield. However, scenarios of future climate from multiple climate models indicate no consensus on future changes in temperature or rainfall volatility, so that either an increase or decrease is plausible. Scenarios with the largest increases in climate volatility are projected to render Tanzanians increasingly vulnerable to poverty through impacts on staple grains production in agriculture, with as many as 90,000 additional people entering poverty on average. Under the scenario where precipitation volatility decreases, poverty vulnerability decreases, highlighting the possibility of climate changes that oppose the ensemble mean, leading to poverty impacts of opposite sign. The results suggest that evaluating potential changes in volatility and not just the mean climate state may be important for analyzing the poverty implications of climate change. 相似文献
140.
Mainstreaming local perceptions of hurricane risk into policymaking: A case study of community GIS in Mexico 总被引:1,自引:0,他引:1
P. Krishna Krishnamurthy Joshua B. Fisher Craig Johnson 《Global Environmental Change》2011,21(1):143-153
This article suggests a framework for incorporating and communicating local perceptions of hurricane risk into policymaking through a case study conducted at El Zapotito commune in the State of Veracruz, Mexico. The authors constructed a geographical information system (GIS)-based model to quantify and spatially assess specific household-level vulnerabilities from information generated through interviews. This research developed a household vulnerability index applied to a participatory GIS to map vulnerability to hurricane hazard. The results indicate that infrastructural weaknesses are the most important factor contributing to vulnerability, explaining on their own 72.2% of the variation in the vulnerability patterns. These findings are corroborated by a vulnerability and capacity assessment (VCA), which shows that the community lacks strategies to cope with unsafe housing. It is suggested that linking community participation with modern techniques to analyse risk can empower communities and mobilise their capacities to address very specific vulnerabilities. 相似文献