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61.
We examined the anthropogenic and natural causes of flood risks in six representative cities in the Gangwon Province of Korea. Flood damage per capita is mostly explained by cumulative upper 5% summer precipitation amount and the year. The increasing flood damage is also associated with deforestation in upstream areas and intensive land use in lowlands. Human encroachment on floodplains made these urban communities more vulnerable to floods. Without changes in the current flood management systems of these cities, their vulnerability to flood risks will remain and may even increase under changing climate conditions.  相似文献   
62.
人地耦合系统脆弱性研究进展   总被引:11,自引:1,他引:10  
当前在以人地耦合系统为中心的气候变化、生态风险和可持续管理等研究中,脆弱性理论及其评价已成为地理学及很多相关学科的研究热点,其涵义不断泛化,内容日渐扩展。不同学科背景的学者对脆弱性解释存在很大分歧,这阻碍了研究的科学化,也影响研究成果的实践意义,迫切需要一个可行的框架来系统整合其理论和实践的研究。从审视脆弱性的理论沿革出发,分析其在国内外可持续发展和全球变化领域的应用现状,总结出分歧的主要原因是对相关概念关系的不理解以及研究时空尺度和学科视角的不明确。基于对脆弱性评价的整合框架的研究现状,选取VSD模型作为统领具体的脆弱性评价的依据。VSD模型的优势在于:①有明确的定义,将脆弱性分解为暴露程度、敏感性和适应潜力3个维度;②用方面层—指标层—参数层逐级递进、细化的方式组织评价数据;③有规范评价流程的8个步骤。最后以我国典型的干旱区为例,运用VSD模型构建了示例区脆弱性评价的指标和参数。  相似文献   
63.
Entitlements are generally defined as the commodities/resources (material and non-material), through which one can establish ownership or command access to resources. Applying this analytic to a case study of everyday water access in Accra, Ghana, we evaluate community water entitlements in two low-income communities with different locational and socio-cultural characteristics. We also evaluate how different entitlements to water map against variable dimensions of vulnerability. The study uses a mixed methods approach including a 200 household survey, focus groups with community members, and semi-structured interviews with local opinion leaders. Our results indicate that in both study communities, an entitlements approach provides a significantly richer portrait of water access beyond availability of piped water infrastructure. Among other factors that are important to everyday negotiations and entitlements related to water access, it is important to consider familial and kin networks, water storing options available to households and vendors, the distance and waiting time to fetch water, and local leaders' perceptions of water issues, particularly how these compare with broader citizen understandings. In this way, an entitlements approach broadens the perspective beyond infrastructural endowments (e.g. piped water), to include a range of other socioeconomic, socio-cultural and local institutional characteristics. Drawing on the empirical examples, as well as related conceptual debates, the study questions how water access is defined, and how water governance processes might benefit from a broader understanding of entitlements, as well as links to differentiated vulnerabilities, notably in times of water-related stress or scarcity.  相似文献   
64.
情境在移动位置服务领域起到融合多源时空数据、模拟地图使用情形及获取用户空间需求的作用。根据作者早期建立的位置地图情境模型,本文基于活动理论构建了位置地图情境三层推理规则,重点描述其基本原理与方法;通过形式化表达将情境推理的结果与位置地图表达联系起来,形成三层推理规则的解析与运行流程;以用户去机场登机为例,假设2种不同情形,验证5种情境事例。实验结果表明,本文的情境推理方法简洁、可操作性强,为进一步研究智能化地图服务提供参考和借鉴。  相似文献   
65.
This study is an attempt to underline the lack of preparedness and the nature of immediate further measures to be taken for facing a moderate earthquake in Indian subcontinents. Surprisingly, moderate to severe damage was noticed in structures located in hundreds of kilometres away from epicentre during last Gorkha earthquake. In this context, the present study makes an effort to validate a proposed modified rapid visual screening schemes for low cost houses frequently available in India. This may be used extensively for quick vulnerability assessment of a locality. Examples of retrofitting measures for typical buildings presented in this study may be useful for upgrading the valuable structures. Thus this study may be helpful for quick vulnerability assessment and adopting retrofitting measures for identified structures for earthquake prone developing countries.  相似文献   
66.
Environmental policy discussion is replete with references to water security, food security, ecosystem health, community resilience, sustainable development, and sustainable urbanism. These terms are, by their very nature, ambiguous and difficult to define; they allow room, however, for a variety of actors to conceptualize water, food, ecological, economic, and urban problems in ways that allow them to move forward on contentious issues. This article focuses on the idea of water security and asks how it is conceptualized and used for regional policy debate in western Canada. We asked fifty-eight water stakeholders from the Saskatchewan River Basin to define water security, identify major barriers to security, and prioritize water problems. Responses showed there are myriad ways to think about water security, ranging from narrow conceptualizations, such as reliability, quality, and quantity, to broader sustainability perspectives about the nature of resource development and its social and economic consequences. The human dimensions of water security (governance, land use, and competing demands) were assigned higher priority than its biophysical aspects (flooding, droughts, and climate change). Framing water security to emphasize the human capacity to manage uncertain and rapid biophysical and societal change offers the opportunity to unite actors who otherwise would be separated by core environmental values, definitions of water security, provincial context (Alberta vs. Saskatchewan), and occupation.  相似文献   
67.
柏林的经济、文化事业发达,是世界的艺术中心、时尚设计中心,也是欧洲文学、媒体、音乐及科学的发展中心。柏林建设了完整的创意设计服务平台、国际推广的本土设计品牌、完善的创意人才培训体系等,以其深厚的文化底蕴实现了城市的创意化发展,并逐步成为国际文化创意的大熔炉。  相似文献   
68.
The growth of maritime transport and oil exploitation activities may increase the risk of oil spills. Thus, plans and actions to prevent or mitigate impacts are needed to minimize the effects caused by oil. However, tools used worldwide to support contingency plans have not been integrated, thus leading to failure in establishing priority areas. This investigation aimed to develop indices of environmental vulnerability to oil (IEVO), by combining information about environmental sensibility to oil and results of numerical modeling of spilled oil. To achieve that, a case study concerning to oil spills scenarios in a subtropical coastal area was designed, and IEVOs were calculated and presented in maps, in order to make the information about the areas’ vulnerability more easily visualized. For summer, the extension of coastline potentially affected by oil was approximately 150 km, and most of the coastline presented medium to high vulnerability. For winter, 230 km coastline would be affected, from which 75% were classified as medium to high vulnerability. Thus, IEVO maps allowed a rapid and clearer interpretation of the vulnerability of the mapped region, facilitating the planning process and the actions in response to an oil spill.  相似文献   
69.
The geospatial field significantly influences the development of the environmental domain, including a wide range of geospatial and cartographic information systems, such as Geographic Information Systems (GIS), Multimedia Atlas Information Systems (MAIS) and more recently web-based GIS (Web-GIS). In this context, we introduce web-based environmental geospatial information systems (Web-EGIS) as a special case of Web-GIS, aiming to integrate the functionalities of geospatial information systems with the enormous quantity of specialized, distributed and highly heterogeneous environmental geo-referenced data and services. We define three main characteristics of the Web-EGIS. The first is a generic hypercube-based data organization and visualization. The next characteristic is a standard-based, three-tier service-oriented architecture. The third and last characteristic is the traceability of the architectural and design decisions, for which we introduce the new concept of an ‘Environmental Application Context’, arguing that not only the functional but also the non-functional requirements (NFRs) have an important role in defining the architecture, software components and data services of such systems. In a nutshell, a Web-EGIS is characterized by a coherent user experience through the hypercube-based visualization concept, technically supported by a service-oriented architecture that is structured according to an extensive analysis of NFRs. On this basis, we introduce the Geodata visualization and interactive training environment (GeoVITe) Platform for Interdisciplinary Environmental Research as a reference implementation of a Web-EGIS with its basic design requirements, integrative hypercube-based visualization for heterogeneous data sources, extended web cartography functionalities, and its de facto system architecture. The concept of the hypercube-based visualization is better transferred to the system architecture by understanding the ‘Environmental Application Context’ of this particular Web-EGIS, which also makes it easier to maintain and enhance. The resulting system is a support platform for research activities in the environmental domain.  相似文献   
70.
In light of the challenges posed by contemporary environmental changes, interest in past environmental impacts and societies’ responses to them is burgeoning. The main strength of such research lies in its ability to analyze completed society-environment interactions. Scholars have argued that such analyses can improve our understanding of present challenges and offer useful lessons to guide adaptation responses. Yet despite considerable differences between past and present societies, our inherently limited knowledge of the past and our changing understanding of it, much of this research uses historical antecedents uncritically, assuming that past societal impacts and responses are directly analogous to contemporary ones. We argue that this approach is unsound both methodologically and theoretically, thus drawing insights that might offer an erroneous course of action.To illustrate the challenges in drawing historical analogies, we outline several fundamental differences between past and present societies as well as broader limitations of historical research. Based on these points, we argue that scholars who apply historical inference in their work should do so critically, while reflecting on the objectives of learning from the past and the limitations of this process. We suggest a number of ways to improve past-present analogies, such as defining more explicitly what we can learn from the past, clarifying the rationale for using the analogy, and reducing the number of variables compared between past and present.  相似文献   
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