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81.
Tristan Sturm  Eric Oh 《Geoforum》2010,41(1):154-163
The aftermath of Hurricane Katrina has piqued interest in the insurance industry, and this scrutiny has led to assumptions that the industry has become unstable and unprofitable with the increased incidence of disasters in highly-insured regions of the world. This paper challenges that assumption by arguing that the insurance industry has responded by spreading risk through scaled and networked recovery schemes. We found that because of competitive strategies of risk-spreading and displacement arrangements, the industry has actually profited as a whole. Regional insurance companies have always relied on the higher financial scales of the reinsurance industry in Munich, Zurich, and London. But with claims reaching into the billions of dollars, the reinsurance industry itself has raised premiums, spread risk farther afield, and jumped scale by spreading risk to futures markets called Alternative Risk Transfers (ARTs). However, the recession beginning in 2008 has called into question the viability of using futures markets as insurance. It is shown through a media analysis of four major business publications (The Economist, The New York Times, The Financial Times and The Wall Street Journal) how the industry responded to the costs of the 2004, 2005, and 2006 hurricane seasons. Because geography is rather new to this literature, this paper also offers a broad review of the insurance industry.  相似文献   
82.
Brent A. Olson 《Geoforum》2010,41(3):447-456
This article examines the history of the Outdoor Recreation Resource Review Commission (ORRRC) in the United States between 1955 and 1963 and efforts to make recreational resources legible for federal governance. By drawing on insights from Critical Resource Geography, I highlight the ways that the ORRRC systematically accounted for and categorized recreational resources, creating a “patchwork landscape” that zoned outdoor recreational resources and promoted efficient use and rational resource conservation. I argue that these efforts required a negotiation between abstraction and an awareness of the situated nature of recreational landscapes.  相似文献   
83.
杨家田  李志明 《云南地质》2010,29(3):262-265
新山金矿属构造剪切带控制的典型金矿床,产于中元古界昆阳群美党组(Pt2m)中部变质石英砂板岩中。规模大、品位富、易采易选。矿区构造——含金剪切带与土壤地球化学金异常,是寻找该类金矿的重要标志。  相似文献   
84.
Deforestation and associated ecological disturbances are the issues of global concern.Researchers have investigated a number of driving forces which accelerate the rate of deforestation at local and regional levels.These include poverty,population growth,market demand and prices,political instability,agricultural expansion and changes in property right and ownership regimes.This paper seeks to explore the impacts of population growth,changing tenure system and other socioeconomic factors on the forest cover of Roghani Valley,located in Hindu Raj Mountains,Northern Pakistan.The present study is mainly based on information collected through participatory observation,selfadministered interviews and questionnaire survey.Geographical Information System(GIS) database is also used for mapping and quantification.The results reveal that in the past three to four decades the study area has been subjected to severe deforestation and about half of the forest area has been converted into barren land.Thus,the area under natural forests decreased from 2099 to 1444 hectares in four decades.This large-scale deforestation is attributed to both proximate and under lying causes particularly traditional land tenure system and demographic development.Consequently,forest resources have been degraded and a number of plant species have disappeared from the forests of the study area while several others are in the process of disappearance.  相似文献   
85.
余辰星  杨岗  陆舟  李东  周放 《海洋与湖沼》2014,45(3):513-521
为了解迁徙季节水鸟在不同滨海湿地中的结构组成和行为特征,于2010年3月、4月、9月、11月和2011年3月,在山口自然保护区及其周边地区对不同滨海湿地类型的水鸟展开调查。结果显示:迁徙季节天然湿地共记录到水鸟6目8科39种,人工湿地有6目9科50种。天然湿地比人工湿地的物种数少,整体数量上,春季人工湿地大于天然湿地,秋季则为天然湿地水鸟数量更多。鹬鸻类在不同滨海湿地类型中觅食行为比例差异显著,在天然湿地中觅食比例达到76.67%,而在人工湿地中则以休息和睡眠等非觅食行为为主。天然湿地是鹬鸻类的重要觅食地,而人工湿地则是鹭类和鹬鸻类的主要休息地。鹭类在两种滨海湿地类型中觅食个体的数量不随潮汐的涨落而相应增减。鹬鸻类随潮汐高度上升,在两种滨海湿地类型中觅食的个体数量减少。山口地区的滨海人工湿地是水鸟在高潮期间天然湿地良好的替代栖息地。  相似文献   
86.
石棉县后沟是一条典型的自然泥石流和矿渣泥石流并存的泥石流沟。本文以石棉后沟为例,结合早期自然泥石流、矿产开采以来矿渣泥石流、以及2013年7 4复合型泥石流,总结了自然泥石流和矿渣泥石流的复合效应,包括泥石流物源补给的多元效应、泥石流发展演化的逆转效应、泥石流起动发生的复杂效应、泥石流动力沿程的放大效应、泥石流致灾破坏的链式效应。对照泥石流对已建防治工程的破坏,提出了自然泥石流和矿渣泥石流复合型泥石流沟防治对策,建议充分利用起动位置和物源集中补给位置的差异,加强对中上游及支沟自然泥石流起动和运动的拦挡防治,最大限度减小自然泥石流对下游矿渣防护工程的基底侵蚀和冲击破坏,从而保障综合防治工程的有效性。  相似文献   
87.
One hundred and twenty one samples from every major plutonic body (mainly granitic) of Greece have been analyzed by γ-ray spectrometry to determine the specific activities of 238U, 232Th and 40K (Bq/kg). The range of the activity concentrations of these radionuclides was 2.3–266.4, 1.8–375.5 and 55.0–1632.0 Bq/kg and their average values were 79.2, 85.3 and 881.4 Bq/kg respectively. Any possible connection between the specific activities of 238U, 232Th and 40K and some characteristics of the studied samples (age, rock-type, colour, grain-size, occurrence and chemical composition) is investigated. Samples of particular colour, rock-type, occurrence and chemical composition have been identified for their distinctive levels of natural radioactivity, while age and grain-size do not affect the concentrations of 238U, 232Th and 40K. The range of the Th/U ratio was 0.7–12.69. This great variation in the Th/U ratios, especially when it is found among the samples of the same pluton, is also discussed and explained by alteration and tectonic–metamorphic processes.  相似文献   
88.
世界各国草地资源管理体制及其对我国的启示   总被引:2,自引:0,他引:2  
草地在世界各大洲均有分布,世界各国对草地资源的管理有着不同的体制与策略.本文梳理了各大洲主要国家的草地资源管理体制,分析了草地资源管理历史进程与趋势,总结了各国草地资源管理的优势和可资借鉴之处.结合我国草地资源管理中存在的问题,建议我国要在国家层面重视草地资源的管理,建立专门行政部门管理全国60忆亩草地,建立健全现有的草地资源管理体制,同时建立草原质量的监测数据网络,并加强对草地利用的监管力度.  相似文献   
89.
自然资源资产管理的国际进展及主要建议   总被引:4,自引:0,他引:4  
自然资源是经济社会发展的物质基础和空间载体,加强自然资源资产管理是适应深化自然资源管理制度改革的现实需要。本文在对比分析国内外自然资源资产管理现状的基础上,剖析了国内自然资源管理中存在的主要问题,提出了加强研究典型国家自然资源资产管理的经验、加快编制我国自然资源资产负债表、加紧落实健全国家自然资源资产管理体制等方面的建议。  相似文献   
90.
介绍了2005年度天文学科科学基金申请、资助的基本情况,并对其结果进行了分析。  相似文献   
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