Doctoral Dissertation Research: Measuring the Environmental Context of Social Vulnerability to Urban Earthquake Hazards: An Integrative Remote Sensing and GIS Approach

虽然许多灾难性事件，如地震，洪水，飓风和龙卷风可以被描述为自然灾害，但与这些事件相关的破坏程度往往与自然力量本身一样多。 如果考虑到与自然灾害有关的风险，情况尤其如此。 本博士论文研究项目将开发一个基于遥感，地理信息系统（GIS）和空间分析技术的城市地震风险生态分析的综合方法。 该研究是由一个概念框架，以人类生态的角度来看，并建议使用的建筑和自然环境作为上下文过滤器，以了解与城市地震灾害相关的社会过程。 研究的主要方向是探索遥感和地理信息系统技术在确定城市土地覆盖属性方面的效用，这些属性与地震灾害的社会脆弱性的高低密切相关。 本研究将检验这样一个假设，即社会脆弱性反映在不同人口群体所占据的城市街区的空间结构特征中，如地理条件、住区的形式和发展以及开放空间的结构。 其中许多特征实际上是由某些城市土地覆盖物属性所代表的，例如建筑材料和土壤类型，从而提供了一种通过使用遥感和地理信息系统来衡量这些特征的相对重要性的手段。 本研究的基本假设将在洛杉矶大都市区进行测试，这是一个动态的，数据丰富的城市地区，在1994年受到重大地震灾害的影响。 研究计划包括三个相互关联的任务。 首先，将利用一套评估美国城市当代城市领域脆弱性的措施，开发一个地理信息系统原型，但不包括遥感变量。 第二，将使用地震前收集的数据来证明遥感图像的效用。 这些数据将提供与研究地点社会脆弱性变化有关的土地覆盖属性的空间明确变量。 第三项任务将包括通过完全根据遥感变量重新评估研究地点的脆弱性来检验这些变量的有效性。 第一项和第三项任务的结果将与1994年地震灾害报告的损失数字进行比较和验证。本项目的动机是希望为脆弱性分析的灵活方法建立一个经验基础，以平衡两个相互竞争的需求。 第一个需要是更好地了解造成脆弱性模式的各种背景和社会因素之间的联系。 第二，需要为在当地开展缓解工作的规划者和决策者提供一种切实可行的方法，以生成脆弱社区的具体概况，并监测这些概况的变化。 因此，该项目的更广泛贡献是理论和经验。 从理论的角度来看，这项研究将有助于灾害研究，回答有关地震风险的生态学问题，以及不同的社会脆弱性是如何连接到城市地区的物理环境的变化。 从经验的观点来看，这一项目的成果将有助于减轻灾害的努力，为决策者提供探索脆弱性模式的工具，从而以满足可持续减轻灾害需要的方式执行政策。 所采用的方法提供了一个模式，说明如何将脆弱性评估技术转化为便于地方政府使用的程序，从而提高地方采取的措施的效力，防止地震灾害成为重大的人类灾害。 这些技术的成本相对较低，因此，可以适当修改这一方法，以拯救其他发达国家和发展中国家的生命。 作为博士论文研究改进奖，该奖项还将提供支持，使有前途的学生建立一个强大的独立的研究生涯。

Although many catastrophic events like earthquakes, floods, hurricanes, and tornadoes may be characterized as natural disasters, the amount of devastation associated with such events often is as much a product of the people and human landscapes where they occur as the natural forces themselves. This is especially true if one tries to consider the risks associated with natural hazards. This doctoral dissertation research project will develop an integrative methodology for the analysis of the ecology of urban earthquake risks based on the techniques of remote sensing, geographic information systems (GIS) and spatial analysis. The research is guided by a conceptual framework that takes a human ecological perspective and suggests the use of the built and natural environments as contextual filters to understand social processes associated with urban earthquake disasters. The major thrust of the research is oriented toward the exploration of the utility of remote sensing and GIS techniques in identifying urban land-cover attributes that are strongly associated with high and low levels of social vulnerability to earthquake hazards. The research will test the hypothesis that social vulnerability is reflected in the characteristics of the spatial structure of the urban neighborhoods that various population groups occupy, such as geographic conditions, the form and development of settlements, and structure of open spaces. Many of these characteristics are physically represented by certain urban land-cover attributes, such as constructions materials and soil types, thus providing a means of measuring the relative importance of such characteristics through the use of remote sensing and GIS. The basic hypothesis of this research will be tested in the Los Angeles metropolitan area, a dynamic, data-rich urban region which was affected in 1994 by a major earthquake disaster. The research plan consists of three interrelated tasks. First, a GIS prototype will be developed using a set of measures for assessing vulnerability in the contemporary urban realm of American cities without the inclusion of remotely sensed variables. Second, the utility of remote sensing imagery will be demonstrated using data collected before the earthquake event. These data will provide spatially explicit variables regarding land-cover attributes associated with variations of social vulnerability in the study sites. The third task will consist of a test of the validity of the remotely sensed variables by re-assessing vulnerability in the study sites based exclusively on such variables. The results of the first and third tasks will be compared and validated against reported damage figures from the 1994 earthquake disaster.The motivation for this project comes from the desire to develop an empirical base for a flexible approach to vulnerability analysis that can balance two competing demands. The first need is to improve the understanding of the linkage among various contextual and social factors that produce vulnerability patterns. The second is the need for offering a practical way for planners and decision makers undertaking local mitigation efforts to generate concrete profiles of vulnerable communities and to monitor changes in these profiles. The broader contributions of this project therefore are both theoretical and empirical. From a theoretical perspective, the research will contribute to hazard research by answering questions regarding the ecology of earthquake risk and how differential social vulnerability is connected to variations in the physical settings of urban areas. From an empirical viewpoint, the product of this project will contribute to hazard mitigation efforts by providing decision makers with tools for exploring patterns of vulnerability and hence for implementing policies in a manner that fulfills the needs of sustainable hazard mitigation. The methods employed offer a model of how to translate the technology for assessing vulnerability into procedures for easy use by local governments, which can increase the effectiveness of locally applied measures that could prevent earthquake hazards from becoming major human disasters. The techniques in question are relatively low-cost and therefore the approach could suitably be modified to save lives in other developed and developing countries. As a Doctoral Dissertation Research Improvement award, this award also will provide support to enable a promising student to establish a strong independent research career.