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Assessing the Vulnerability of Coastal Communities to Extreme Storms: The Case of Revere,MA., USA 总被引:6,自引:1,他引:6
Clark George E. Moser Susanne C. Ratick Samuel J. Dow Kirstin Meyer William B. Emani Srinivas Jin Weigen Kasperson Jeanne X. Kasperson Roger E. Schwarz Harry E. 《Mitigation and Adaptation Strategies for Global Change》1998,3(1):59-82
Climate change may affect the frequency, intensity, and geographic distribution of severe coastal storms. Concurrent sea-level
rise would raise the baseline of flooding during such events. Meanwhile, social vulnerability factors such as poverty and
disability hinder the ability to cope with storms and storm damage. While physical changes are likely to remain scientifically
uncertain into the foreseeable future, the ability to mitigate potential impacts from coastal flooding may be fostered by
better understanding the interplay of social and physical factors that produce human vulnerability. This study does so by
integrating the classic causal model of hazards with social, environmental, and spatial dynamics that lead to the differential
ability of people to cope with hazards. It uses Census data, factor analysis, data envelopment analysis, and floodplain maps
to understand the compound social and physical vulnerability of coastal residents in the city of Revere, MA, USA.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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Low Genetic Variability in the Hawaiian Monk Seal 总被引:1,自引:0,他引:1
Maria B. Kretzmann William G. Gilmartin Axel Meyer Gerard P. Zegers Steven R. Fain Bruce F. Taylor & Daniel P. Costa 《Conservation biology》1997,11(2):482-490
The Hawaiian monk seal ( Monachus schauinslandi) is a critically endangered species that has failed to recover from human exploitation despite decades of protection and ongoing management efforts designed to increase population growth. The seals breed at five principal locations in the northwestern Hawaiian islands, and inter-island migration is limited. Genetic variation in this species is expected to be low due to a recent population bottleneck and probable inbreeding within small subpopulations. To test the hypothesis that small population size and strong site fidelity has led to low within-island genetic variability and significant between-island differentiation, we used two independent approaches to quantify genetic variation both within and among the principal subpopulations. Mitochondrial control region and tRNA gene sequences (359 base pairs) were obtained from 50 seals and revealed very low genetic diversity (0.6% variable sites), with no evidence of subpopulation differentiation. Multilocus DNA fingerprints from 22 individuals also indicated low genetic variation in at least some subpopulations (band-sharing values for "unrelated" seals from the same island ranged from 49 to 73%). This method also provided preliminary evidence of population subdivision ( F'st estimates of 0.20 and 0.13 for two adjacent island pairs). Translocations of seals among islands may therefore have the potential to relieve local inbreeding and possibly to reduce the total amount of variation preserved in the population. Genetic variation is only one of many factors that determine the ability of an endangered species to recover. Maintenance of existing genetic diversity, however, remains an important priority for conservation programs because of the possibility of increased disease resistance in more variable populations and the chance that inbreeding depression may only be manifest under adverse environmental conditions. 相似文献
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The tropical alga Neomeris annulata (Dickie) (Dasycladaceae: Chlorophyta) produces brominated sesquiterpenes and deposits aragonite throughout the thallus. This study, conducted throughout 1990–1991, showed that the fleshy, apical portions of the thalli (tips) were high in secondary metabolite concentrations (1.5%, mean combined secondary metabolites based on dry mass) and relatively low in calcium carbonate (aragonite form) (65.2% ash). The basal portions were lower in combined secondary metabolites (0.2% dry mass), and higher in aragonite (90.0% ash). The crude organic extract of the alga deterred fish feeding in the field at concentrations of 5, 10 and 15% dry mass, but not at a lower concentration of 1.5%. Natural concentrations of crude organic extract ranged from 1.5 to 15.3% in whole individuals and averaged 5.1% based on dry mass. Two brominated sesquiterpenes were isolated as major metabolites from the crude extract, but only one deterred feeding at natural concentrations. Ash concentrations in N. annulata were 60% dry mass in both the tips and bases. Aragonite strongly deterred feeding at concentrations of 65 and 90% dry mass. When a naturally occurring combination of organic extract and aragonite in the tips (10% crude extract and 65% aragonite) was compared with that of the bases (0.8% crude extract and 90% aragonite), no significant difference in grazing was observed. Combinations of secondary metabolites and aragonite were also tested against one or the other single defense. The combination of defenses proved a more effective deterrent than either secondary metabolites or aragonite alone. 相似文献
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Long RW Eatough NL Eatough DJ Meyer MB Wilson WE 《Journal of the Air & Waste Management Association (1995)》2005,55(12):1839-1846
Fine particulate matter (PM2.5) mass was determined on a continuous basis at the Salt Lake City Environmental Protection Agency Environmental Monitoring for Public Awareness and Community Tracking monitoring site in Salt Lake City, UT, using three different monitoring techniques. Hourly averaged PM2.5 mass data were collected during two sampling periods (summer 2000 and winter 2002) using a real-time total ambient mass sampler (RAMS), sample equilibration system (SES)-tapered element oscillating microbalance (TEOM), and conventional TEOM monitor. This paper compares the results obtained from the various monitoring systems, which differ in their treatment of semivolatile material (SVM; particle-bound water, semivolatile ammonium nitrate, and semivolatile organic compounds). PM2.5 mass results obtained by the RAMS were consistently higher than those obtained by the SES-TEOM and conventional TEOM monitors because of the RAMS ability to measure semivolatile ammonium nitrate and semivolatile organic material but not particle-bound water. The SES-TEOM monitoring system was able to account for an average of 28% of the SVM, whereas the conventional TEOM monitor loses essentially all of the SVM from the single filter during sampling. Occasional mass readings by the various TEOM monitors that are higher than RAMS results may reflect particle-bound water, which, under some conditions, is measured by the TEOM but not the RAMS. 相似文献
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