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101.
Kim N 《Disasters》2012,36(2):195-211
This paper proposes a simple indicator to measure the exposure to natural disasters for the poor and non-poor population, in order to assess the global and regional trend of natural hazard and poverty. Globally, poor people are two times more exposed to natural disasters than the non-poor in the twenty-first century. The time trend varies across regions, with poor people in East Asia and Pacific being most exposed to natural disasters, followed by those in South Asia and Sub-Saharan Africa. The change of exposure measure over time is decomposed into two factors: a pure exposure change, which could be fuelled by climate change; and a concentration component. The result shows that the total net increase of exposure between the 1970s and the 2000s is driven significantly by the increased concentration of the poor (26 per cent) in disaster-prone areas, whereas the contribution of that factor remains very small for the non-poor (six per cent).  相似文献   
102.
Health hazard from natural radioactivity in Brazilian granites, covering the walls and floor in a typical dwelling room, was assessed by indirect methods to predict external gamma-ray dose rates and radon concentrations. The gamma-ray dose rate was estimated by a Monte Carlo simulation method and validated by in-situ measurements with a NaI spectrometer. Activity concentrations of 232Th, 226Ra, and 40K in an extensive selection of Brazilian commercial granite samples measured by using gamma-ray spectrometry were found to be 4.5-450 Bq kg−1, 4.9-160 Bq kg−1 and 190-2029 Bq kg−1, respectively. The maximum external gamma-ray dose rate from floor and walls covered with the Brazilian granites in the typical dwelling room (5.0 m × 4.0 m area, 2.8 m height) was found to be 120 nGy h−1, which is comparable with the average worldwide exposure to external terrestrial radiation of 80 nGy h−1 due to natural sources, proposed by United Nations Scientific Committee on the Effects of Atomic Radiation. Radon concentrations in the room were also estimated by a simple mass balance equation and exhalation rates calculated from the measured values of 226Ra concentrations and the material properties. The results showed that the radon concentration in the room ventilated adequately (0.5 h−1) will be lower than 100 Bq m−3, value recommended as a reference level by the World Health Organization.  相似文献   
103.
北京城市水系水环境模拟及情景分析   总被引:1,自引:0,他引:1  
城市水系是流域水环境管理中最为脆弱的控制点.针对城市水系水动力条件差、有机污染和富营养化严重的问题,应用QUAL2K模型模拟、预测城市水系水环境的时空变化,并在此基础上探讨北环水系水环境管理和污染防治的合理有效方案.结果显示,经过多次调整后的模型模拟的匹配度达到了0.9135,水温、溶解氧、COD、TN、TP和Chl-...  相似文献   
104.
超富集植物的筛选是植物修复重金属污染土壤技术的核心内容.采用盆栽试验的方法,研究了Cd胁迫下添加营养元素N、P、K和螯合剂乙二胺四乙酸(EDTA)对三叶鬼针草(Bidens pilosa L.)的生长反应和生理生化特性以及对Cd的吸收积累特征.盆栽试验结果显示,在Cd为10 mg/kg时,添加营养元素N、P、K和EDT...  相似文献   
105.
After a prolonged drafting and consultation process, South Africa has introduced a new royalty charge to holders of mineral development rights. Deciding on an acceptable royalty is a complex process, especially when it targets deceptive economic rents. This is achieved with a variable royalty rate that slides in tandem with mine profitability. The base is sales revenue and to compensate for the need to charge for the mineral in its unprocessed form, refined production is charged at a lower rate. The aim of this paper is to discuss the Royalty Act in the context of its background, the underlying theory and fundamental principles. This paper argues that the fundamental principles on which the Act is based are sound, but raises a concern on potentially high compliance and reporting costs.  相似文献   
106.
人类承载力"K值"影响因素   总被引:1,自引:0,他引:1  
人类承载力“K值”表示地球能承载人口的极限值。“K值”的影响因素的繁多以及相互间的联系使得“K值”确切数值的计算成为一项非常艰巨的任务。通过分析人类与自然的关系,探讨人类承载力的微观影响因素及其相互关系,从开放生态系统的性质讨论人类承载力的宏观影响因素。从而得出人类承载力受渐变和突变因素的结合控制。以此揭开承载和调控人类种群的机理并预测“K值”的可能发展趋势,达到避免计算“K值”确切数值而又能提出人口增长对策和可持续发展的指导意见的目的。  相似文献   
107.
农药化工厂生产苯肼、苯唑醇、乙基氯化物过程排放的废水是高氯难生物降解有机废水,采用三辛胺作萃取剂,用液-液萃取处理,三辛胺与水中Cl-离子形成萃合物而使Cl-转移到有机相.再经高效絮凝处理后,CODCr总去除率达89.8%,Cl-总去除率达83.2%,BOD/COD比从0.02上升到0.34,可生化性大幅度提高. 废水再经河水稀释进A/O池生化处理3d后,可达标排放.负载萃取液用5%NaOH水溶液反萃取.由于萃取剂回用降低了处理费用.  相似文献   
108.
宣化城区大气TSP浓度特征及来源分析   总被引:7,自引:0,他引:7  
以宣化区大气环境监测数据为基础,评价了宣化城区非采暖期和采暖期TSP污染的现状,分析了TSP污染的日变化特征.根据X荧光分析测定的TSP元素成分,采用因子分析法探讨了TSP污染的来源.宣化城区TSP在非采暖期以冶金行业排放为主要来源,采暖期则以燃煤为主要来源.最后,针对污染物来源提出了城区TSP污染控制对策.   相似文献   
109.
自然与环境资源价值评估的误区   总被引:9,自引:0,他引:9  
资源环境价值计量近年来成为资源与环境经济学的研究热点,但却因为在许多最基本的问题上迷失了方向,产生了不少似是而非的问题。被混淆的问题包括:①实物意义上的稀缺与经济学上的稀缺;②使用价值与交换价值;③边际价值与全部价值;④成本与价值;⑤个人消费者价值与社会价值。论文主要目的是通过澄清这些问题来指出如何对自然与环境资源估价。  相似文献   
110.
Decision makers and researchers recognize the need to effectively confront the social dimensions and conflicts inherent to invasive species research and management. Yet, despite numerous contentious situations that have arisen, no systematic evaluation of the literature has examined the commonalities in the patterns and types of these emergent social issues. Using social and ecological keywords, we reviewed trends in the social dimensions of invasive species research and management and the sources and potential solutions to problems and conflicts that arise around invasive species. We integrated components of cognitive hierarchy theory and risk perceptions theory to provide a conceptual framework to identify, distinguish, and provide understanding of the driving factors underlying disputes associated with invasive species. In the ISI Web of Science database, we found 15,915 peer‐reviewed publications on biological invasions, 124 of which included social dimensions of this phenomenon. Of these 124, 28 studies described specific contentious situations. Social approaches to biological invasions have emerged largely in the last decade and have focused on both environmental social sciences and resource management. Despite being distributed in a range of journals, these 124 articles were concentrated mostly in ecology and conservation‐oriented outlets. We found that conflicts surrounding invasive species arose based largely on differences in value systems and to a lesser extent stakeholder and decision maker's risk perceptions. To confront or avoid such situations, we suggest integrating the plurality of environmental values into invasive species research and management via structured decision making techniques, which enhance effective risk communication that promotes trust and confidence between stakeholders and decision makers. Clarificar los Valores, Percepciones de Riesgo y Actitudes para Resolver o Evitar Conflictos Sociales en el Manejo de Especies Invasoras  相似文献   
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