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851.
Identifying and mapping community vulnerability 总被引:30,自引:1,他引:29
Morrow BH 《Disasters》1999,23(1):1-18
Disaster vulnerability is socially constructed, i.e., it arises out of the social and economic circumstances of everyday living. Most often discussed from the perspective of developing nations, this article extends the argument using American demographic trends. Examples from recent disasters, Hurricane Andrew in particular, illustrate how certain categories of people, such as the poor, the elderly, women-headed households and recent residents, are at greater risk throughout the disaster response process. Knowledge of where these groups are concentrated within communities and the general nature of their circumstances is an important step towards effective emergency management. Emergency planners, policy-makers and responding organisations are encouraged to identify and locate high-risk sectors on Community Vulnerability Maps, integrating this information into GIS systems where feasible. Effective disaster management calls for aggressively involving these neighbourhoods and groups at all levels of planning and response, as well as mitigation efforts that address the root causes of vulnerability. 相似文献
852.
M. Brasseur-Daudruy C. Garel V. Brossard F. Broux B. Heckettsweiler D. Eurin 《黑龙江环境通报》2006,26(13):1254-1255
We suggest the term ‘hyper-echogenic colon’ to describe a hyperechoic foetal colonic content with no other intestinal abnormality. This is a rare pattern, which to our knowledge, has never been correlated with a specific pathology. The accidental observation of a cystine kidney stone in an infant who presented with this sign during the prenatal period made it possible to diagnose this disease retrospectively in two other children. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
853.
Among recent lemmings (D. torquatus from the Yamal Peninsula and D. groenlandicus from Somerset, Bathurst, Melville, and Devon islands), there are populations with archaic sets of morphotypes characteristic of the end of the Late Pleistocene. In some parts of the species range, lemming morphotypes follow the pattern characteristic of the Holocene stage of their evolution. Lemmings with the best developed tooth system live in the Bering Sea sector of the Arctic (Wrangel Island, Chukotka and Alaska). The correspondence of the boundaries of the groups distinguished by odontological traits to the phylogeographic data on mitochondrial DNA (mtDNA) and chromosomal groups is discussed. 相似文献
854.
Robert B. Olshansky 《Journal of Environmental Planning and Management》1996,39(3):371-386
Landslides continue to be an expensive problem in the U nited States. This paper explores the difficult problem of how to pay for reducing existing landslide risks. The paper examines a hierarchy of methods to cover repair and long term maintenance of unstable areas: assessment districts; homeowner associations; and insurance. It looks at several examples, and finds that costs in all but the worst cases average about $5000 to $15 000 per property. Landslide insurance is shown to be feasible and could be designed so as to encourage mitigation. The paper concludes that an optimal approach for mitigation and compensation would combine insurance with assessment districts. 相似文献
855.
David R. Breininger Vickie L. Larson Brean W. Duncan Rebecca B. Smith Donna M. Oddy Michael F. Goodchild 《Conservation biology》1995,9(6):1442-1453
Remote sensing and geographical information systems are used to analyze landscapes important to species of conservation concern. The accuracy of the methods depends on how closely habitat mapping classes are linked to population demography. Habitat use by Florida Scrub Jays ( Aphelocoma c. coemlescens ) was quantified using circular plots. Habitat variation was mapped using high-resolution aerial photography on a site where all Florida Scrub Jays were color-banded. Nest site selection, nest success, yearling production, and breeder survival were measured within Florida Scrub Jay territories. Habitat use was lowest in areas without scrub oaks or areas within 136 m from forests. Open oak, dominated by scrub oaks and open sandy areas, had the highest use and nest success among habitats. Open oak occurred as narrow patches ( <20 m wide) in landscapes dominated by matrix habitat (palmetto-lyonia and swale marshes). Most wide patches (>50 m) of open oak were potential population sources, where reproduction exceeded mortality. Areas with patches of open oak of less than 1 ha were usually population sinks. Open oak occurred as less flammable patches in a landscape subject to frequent fires. Population sources varied temporally and spatially with fires and site potential to support scrub oaks (soils). Analyses of landscape patterns and dynamics indicated that habitat mapping should not only include patches of currently optimal habitat but should also include landscapes associated with open oak. The influences of landscape patterns on habitat use, reproductive success, survival, and territory size can be quantified at different scales starting with attributes associated with habitat patches, nest sites, and territories. Potential mapping errors occur, however, when habitats are used to quantify the areal extent of sources and sinks and similar population attributes important for species persistence. 相似文献
856.
Duane B. Oyen Jerald R. Barnard 《Journal of the American Water Resources Association》1975,11(3):483-490
ABSTRACT: This study examines agricultural land use change in the flood plain of the Iowa River as a result of building the Coralville Dam. Estimates of land use change and the benefits realized from the project are compared to the original project study benefits estimated by the Corps of Engineers. An analysis of the factors affecting land use change is carried out through a regression model to determine those variables that explain observed land use change. 相似文献
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