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251.
Bakir  P.G. 《Natural Hazards》2004,33(3):405-425
While laboratory and analytical studies can provide valuable information about earthquake hazard mitigation, the most effective educator is the impact of a full-scale earthquake on a full-scale city. The recent earthquakes in Turkey showed that the governmental as well as individual attitudes towards earthquakes did not represent proportionate responses to the risk levels concerned. Turkey had weaknesses in preparing, planning, mitigating and responding to disasters in spite of the known seismic vulnerability of the country. Many steps have been taken after 1999 earthquakes in Turkey, however, the preparations largely concentrate on the response and recovery phases and a fundamental step to reform the current disaster management system and steps to rehabilitate the vulnerable building stock has not been undertaken until today. This would involve changing the present laws and regulations and de-centralising the disaster management system. The aim of this paper is to propose a national mitigation strategy for Turkey for a time-frame of 10 years. The model proposed is a very comprehensive model for earthquake risk reduction in Turkey and within this context, the legislative and technical aspects of mitigation will be discussed in detail. Strategies for mitigating and retrofitting the existing building stock will also be proposed.  相似文献   
252.
A series of experiments was conducted to determine the potential for aeolian abrasion of natural dune sands to produce fine particles (< 125 µm) by (1) the release of resident fines; (2) spalling, chipping and breakage of particles; and (3) the removal of grain surface coatings. Parent samples were obtained from the surfaces of four active continental dunes and abraded using a glass ‘test tube’ chamber for up to 120 h. The fine particles produced by this abrasion process were trapped at varying time intervals and subject to detailed particle‐size analyses using a Coulter Multisizer. The abrasion of untreated parent samples produced fine particles in one of two main size classes, < 10 µm and > 50 µm, but when the parent sample was sieved to exclude particles < 250 µm, relatively more material in the range 10–50 µm was produced. For unsieved parent samples, the size range associated with the dominant mode varied according to the length of the abrasion time. The coarsest mode (> 63 µm) was dominant during the first 16 h of abrasion, then became less significant and is thought to be associated with the release of resident fines into suspension. The finest mode (< 10 µm) was absent or very weak during the first 16 h of abrasion, then became more significant and, in some instances, dominated the distribution as abrasion continued. Removal of grain surface coatings is the main source of fine material < 10 µm, and this may be a significant source of fine material in areas where sands are dominated by subrounded and rounded particles. By comparison with previous studies of aeolian particle abrasion, these natural dune sands produced very low quantities of fine material (by weight), but their spatial extent makes them potentially a significant source of dust‐sized particles at the global scale.  相似文献   
253.
Coastal steepening potentially presents an array of management issues in the form of financial implications of sea defence degradation, increased risk posed to the hinterland as wave attenuation is reduced, 'coastal squeeze' and statutory requirements in the light of the Habitats Directive. The extent to which coastal steepening has occurred throughout England and Wales has been investigated through use of a GIS and dataset based on historical Ordnance Survey map information. Data were collected along 1084 selected profile lines, positioned so as to be geomorphologically representative of the coast. Features recorded from each map year included the positions of mean high water (MHW) and mean low water (MLW), the relative movements of which infer changing intertidal gradients. The results presented in this paper are on a subject and scale not previously published. It is revealed that 61% of the coastline studied has experienced a tendency towards steepening. Of the remainder, 33% has flattened, and 6% has experienced no rotational movement. This tendency towards steepening has been the dominant movement on each of the west, south, and east coasts.  相似文献   
254.
El Hatillo is a rural community in the Sébaco valley in Nicaragua, which suffers from an eroding resource base, high levels of poverty and malnutrition, and a high susceptibility to hazards. Structural adjustment policies have been devastating for small and subsistence farmers and have increased the level of economic, social and environmental marginalisation in rural Nicaragua. This paper explores initiatives to promote sustainable development in Nicaragua in the context of structural adjustment and environmental degradation. Drawing on qualitative research conducted in El Hatillo, it outlines the ways in which women in this community are attempting to address the multiple challenges of rural poverty and environmental risk and considers the potential of these strategies for gender equality.  相似文献   
255.
一体化基础地形地籍数据库的设计思想   总被引:1,自引:0,他引:1  
结合某地市级一体化基础地形地籍建设工程,主要介绍了一体化基础地形籍数据库的总体设计思想.对几个值得特别注意的关键技术问题进行了探讨,并给出了基本解决方法。  相似文献   
256.
土地利用动态管理系统研发中的若干问题研究   总被引:2,自引:0,他引:2  
土地利用管理是土地管理的核心内容之一。土地利用动态变化加剧了土地管理的压力,建设具有辅助决策功能的土地利用动态信息系统是大势所趋。本文在阐述建设此系统的重要意义基础上,讨论了系统研发中几个关键问题,即“动态”管理的实现、空间数据和属性数据集成管理和决策的初步实现等。本文提出的解决方法,对于类似土地信息系统的建设具有普遍的指导意义。  相似文献   
257.
Global dust trajectories indicate that signi?cant quantities of aeolian‐transported iron oxides originate in contemporary dryland areas. One potential source is the iron‐rich clay coatings that characterize many sand‐sized particles in desert dune?elds. This paper uses laboratory experiments to determine the rate at which these coatings can be removed from dune sands by aeolian abrasion. The coatings impart a red colour to the grains to which previous researchers have assigned variable geomorphological signi?cance. The quantities of iron removed during a 120 hour abrasion experiment are small (99 mg kg?1) and dif?cult to detect by eye; however, high resolution spectroscopy clearly indicates that ferric oxides are released during abrasion and the re?ectance of the particles alters. One of the products of aeolian abrasion is ?ne particles (<10 µm diameter) with the potential for long distance transport. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
258.
从信息技术的角度看,工程勘察实际上是一种“信息获取、信息理解和信息应用”的过程。作为一项技术和服务,工程勘察的信息化应由工程勘察业务信息化和工程勘察管理信息化两方面组成。工程勘察信息化的作用包括信息化辅助业务和管理、信息化支撑业务和管理以及信息化提升业务和管理三个层次。当前,有必要对工程勘察企业信息化的模式、工程勘察业务信息化提升的方式和工程勘察信息化的标准化等问题做进一步研究,以推动工程勘察信息化向深度和广度发展。  相似文献   
259.
Local geography and gender are two major factors determining which crop varieties are cultivated in a case study of two rural villages in Bangladesh. This paper explores the interrelationships between gender, agrobiodiversity, and the use of, and preferences for, improved and local crop varieties. These are examined in relation to rice, minor field crops, and home garden fruits and vegetables. Reasons for both the displacement and the persistence of local varieties (LVs) are analysed in comparison to improved variety (IV) diffusion. The research evaluates agrobiodiversity through the number, types, and varieties of crops grown in fields and home gardens. The desired agroecological, economic, and cultural characteristics of crops grown document how respondents rank their variety preferences. Variety preferences and the perceived importance of LV preservation are compared with what is actually grown. The study indicates that there was little variation between villages in their approach towards the use of IV and LV rice; IVs were cultivated for their high yields and LV rice for taste and culinary uses. However, there were significant differences in relative agricultural dependence between the two villages which led to unique variety preferences. In both villages, women's preferences for IVs or LVs play a major role in crop choices, particularly as they manifest themselves in gendered domains of authority.  相似文献   
260.
Emerging approaches to environmental governance require a greater level of community participation than did previous approaches in which these responsibilities largely rested with government agencies. There is consequently a need for increased engagement with NRM among a broad community sector. This paper examines initiatives by two prominent government agencies, the Murray–Darling Basin Commission (MDBC) and the National Museum of Australia (NMA), to engage school children from regional communities using education programs that focus on place and environmental health. We focus on the MDBC's International Riverhealth Conference held in Mildura in 2003 and the associated Murray–Darling Basin TalkBack Classroom sponsored by the NMA and the Parliamentary Education Office (PEO). We explore how key themes of local scale, place-based identities, youth voice and critical engagement are developed in these programs and consider how they relate to the environmental agency of children. We then reflect on the potential for the kinds of environmental agency promoted through these programs to help build the capacity of local communities to progress larger goals of environmental restoration and sustainability in the Murray–Darling Basin. The evaluation research reported here forms part of the Committing to Place research project, an Australian Research Council Linkage grant involving the University of Tasmania, the National Museum of Australia and the Murray–Darling Basin Commission.  相似文献   
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