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291.
Ashleigh Elain McKinzie 《Disasters》2017,41(1):3-22
A commonly‐held belief is that natural disasters do not discriminate. This paper, though, poses the following theoretical question: what does the elision of race, class, and gender in the news media say about disasters in the neoliberal era? It draws on the author's analysis of two prominent newspapers—The New York Times and USA Today—and their coverage of the recovery process after devastating tornadoes in two towns in the United States (Tuscaloosa, Alabama, and Joplin, Missouri) in 2011. The study asserts that the narrative of the news media is one with which people are familiar and that it fits into larger ‘formula stories’. It utilises theoretical treatments of narrative to demonstrate how differences are erased and how they lead to complicity in hegemonic representations. Critical theory is used to elucidate why this occurs, and the paper sources Goldberg (2002) in suggesting that the news media employs ‘fantasies of homogenisation’ when representing post‐disaster communities. 相似文献
292.
293.
Water availability in arid regions is both sporadic and highly variable in quantity. If the water quality shows large variations
of salinity and concentration of other chemical constituents with depth and time span, it has considerable effect on the entire
hydrological set up of the area. In the Saidabad tahsil area, the deep aquifers that supply water to borewells in the alluvial
plain of the Mathura region, Uttar Pradesh, have higher salinity than those of the dugwells from the shallow aquifers. The
excessive drilling of tubewells and high yield tubewells are resulting in deterioration of water quality of the shallow aquifers.
On the contrary, the chemical constituents such as, Na+, K
+, Cl
-, andHCO
3
- show higher concentration in shallow aquifers than deep aquifers. A study carried out to monitor water quality in this region
reveals that the groundwater quality varies with depth and time span in shallow and deep aquifers. Factors controlling variations
in salinity and concentration of chemical constituents of the water in the two types of aquifers are discussed. The relative
merits of the shallow water for potability are pointed out with respect to salinity concentrations and public health. 相似文献
294.
为研究灾变时期井下避难硐室进出口有毒气体CO入侵弥散问题,基于等效原理,利用Gambit软件建立地面钻孔正压通风避难硐室物理模型和开门状态下有毒气体进入避难硐室的流体力学原理及气体弥散数学模型,并利用Fluent软件模拟钻孔压风量与室内CO浓度变化关系,提出在避难硐室的隔离门前加装门衬的办法,使避难人员穿过避难硐室门时... 相似文献
295.
296.
Pollution by toxic metals including cadmium (Cd) and hypoxia are important stressors in estuaries and coastal waters which may interactively affect sessile benthic organisms, such as oysters. We studied metabolic responses to prolonged hypoxic acclimation (2 weeks at 5% O2) in control and Cd-exposed (30 d at 50 μg L−1 Cd) oysters Crassostrea virginica, and analyzed the effects of these stressors on abundance of Vibrio spp. in oysters. Hypoxia-acclimated oysters retained normal standard metabolic rates (SMR) at 5% O2, in contrast to a decline of SMR observed during acute hypoxia. However, oysters spent more time actively ventilating in hypoxia than normoxia resulting in enhanced Cd uptake and 2.7-fold higher tissue Cd burdens in hypoxia. Cd exposure led to a significant decrease in tissue glycogen stores, increase in free glucose levels and elevated activity of glycolytic enzymes (hexokinase and aldolase) indicating a greater dependence on carbohydrate catabolism. A compensatory increase in activities of two key mitochondrial enzymes (citrate synthase and cytochrome c oxidase) was found during prolonged hypoxia in control oysters but suppressed in Cd-exposed ones. Cd exposure also resulted in a significant increase in abundance of Vibrio parahaemolyticus and Vibrio vulnificus levels during normoxia and hypoxia, respectively. Overall, Cd- and hypoxia-induced changes in metabolic profile, Cd accumulation and bacterial flora of oysters indicate that these stressors can synergistically impact energy homeostasis, performance and survival of oysters in polluted estuaries and have significant consequences for transfer of Cd and bacterial pathogens to the higher levels of the food chain. 相似文献
297.
As part of a comprehensive environmental management system, many countries establish emission control targets for mass emissions of a pollutant. Such targets are often the key objective of an environmental policy, such as an emission trading program. In China, however, it is more than just an objective of one particular policy; it has become a concept that has influenced many national environmental policies and activities. The objective of this article is to review the implementation of the total emission control policy in the past 10 years and explore emerging issues in its implementation. The article has three sections: a summary of the implementation experience, issues with the design and implementation of the policy, and policy recommendations. 相似文献
298.
甘肃河西走廊临泽小枣冻害成因及防治对策 总被引:3,自引:0,他引:3
进入21世纪的短短几年里,甘肃河西走廊临泽小枣就遭受了2次冻害,2008年的冻害比2003年更为严重,位于临泽县北部的四个乡镇的枣粮间作地,全部幼树和绝大部分大树树冠均冻死、绝产.冻害程度调查表明,临泽县南部乡镇轻,北部乡镇重;村庄宅旁轻,枣粮间作地重;靠近林带和小网格林带内轻,远离林带和大网格林带内重;背风面轻,迎风面重.气象资料分析得出,2003年冻害是由于2002年12月下旬的低温所致;2008年冻害是1月下旬到2月上旬的低温所致,冻害期间,最大风力为西北风,吹得最多的是东北风.通过与正常年份气温的比较分析得出,临泽小枣安全越冬的临界气温为-20.0℃,2d日平均温度低于-20℃的低温即可使临泽小枣遭受冻害,但≤1d的-20℃以下的低温对临泽小枣不产生冻害;温度越低,枣树能忍受的时间越短,可忍受的极端最低气温为-27℃.加强绿洲防护体系建设,大力发展村旁、路旁、渠旁、宅旁等四旁枣树种植,及根据天气预报采取应急措施是防止临泽小枣发生冻害的主要对策. 相似文献
299.
The accumulated knowledge and perceptions of communities 'at risk' are key elements in managing disaster risk at the local level. This paper demonstrates that local knowledge of flood hazards can be structured systematically into geographic information system (GIS) outputs. When combined with forecasting models and risk scenarios, they strengthen the legitimacy of local knowledge of at-risk populations. This is essential for effective disaster risk reduction practices by external actors, local non-governmental organisations (NGOs) and municipal authorities. The research focused on understanding coping strategies and 'manageability' of flood hazards as defined by communities. 'Manageability' is how people experience flooding in relation to their household capacity and the coping mechanisms available. The research in the Philippines highlights the significance of localised factors, including socioeconomic resources, livelihoods, seasonality and periodicity, for understanding manageability. The manageability concept improves practice at the municipal level by legitimising local coping strategies, providing better indicators, and developing understanding of flooding as a recurrent threat. 相似文献
300.
Waldner P Schaub M Graf Pannatier E Schmitt M Thimonier A Walthert L 《Environmental monitoring and assessment》2007,128(1-3):5-17
Air pollution affects forest health through atmospheric deposition of acidic and nitrogen compounds and elevated levels of
tropospheric ozone (O3). In 1985, a monitoring network was established across Europe and various research efforts have since been undertaken to
define critical values. We measured atmospheric deposition of acidity and nitrogen as well as ambient levels of O3 on 12, 13, and 14 plots, respectively, in the framework of the Swiss Long-Term Forest Ecosystem Research (LWF) in the period
from 1995 to 2002. We estimated the critical loads of acidity and of nitrogen, using the steady state mass balance approach,
and calculated the critical O3 levels using the AOT40 approach. The deposition of acidity exceeded the critical loads on 2 plots and almost reached them
on 4 plots. The median of the measured molar ratio of base nutrient cations to total dissolved aluminium (Bc/Al) in the soil
solution was higher than the critical value of 1 for all depths, and also at the plots with an exceedance of the critical
load of acidity. For nitrogen, critical loads were exceeded on 8 plots and deposition likely represents a long-term ecological
risk on 3 to 10 plots. For O3, exceedance of critical levels was recorded on 12 plots, and led to the development of typical O3-induced visible injury on trees and shrubs, but not for all plots due to (1) the site specific composition of O3 sensitive and tolerant plant species, and (2) the influence of microclimatic site conditions on the stomatal behaviour, i.e.,
O3 uptake. 相似文献