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991.
G317线是我国西藏地区最主要的干线公路之一,是内地与西藏地区经贸流通的重要通道。但是西藏地区环境恶劣,公路路基水毁灾害非常频繁,常常影响公路通行。本文从G317线公路路基水毁的实地调查资料出发,综合分析影响路基水毁发育的因素,对其水毁危险性进行分段研究。经过研究将G317线分为极度危险段、高度危险段、中度危险段、低度危险段、微度危险段和暂无危险段6个路基水毁危险度级别,并对每个危险度级别进行评述.  相似文献   
992.
ABSTRACT: This study aimed to clarify public preferences for flood control measures in Japan, willingness to pay (WTP), and the main factors involved in WTP by applying the contingent valuation method. Findings showed that most residents surveyed expected some flood control measures, and revealed a diversity of interest in river management. WTP levels for different measures ranged from a mean of ¥2,887 to ¥4,861 and from a median of ¥1,000 to ¥2,000. However, WTP for additional flood risk reduction beyond initial levels was found to be zero. This was considered to be because WTP for flood risk reduction must be determined within a multi‐risk context. WTP for flood control measures may increase with per capita income, individual preparedness, and/or experience with flooding, but may decrease with distance from a river, acceptability of flood risk, and provision of environmental information. Furthermore, perception of flood risk may increase WTP, while perception of other risks may decrease it. Methods of dealing with environmental risk that were proposed in the survey may have affected WTP levels.  相似文献   
993.
ABSTRACT: Assessment and control of nutrient losses from paddy fields is important to protect water quality of lakes and streams in Korea. A four‐year field study was carried out to investigate water management practices and losses of nitrogen (N) and phosphorus (P) in rice paddy irrigation fields in southern Korea. The amount and water quality of rainfall, irrigation, surface drainage, and infiltration were measured and analyzed to estimate inputs and losses of N and P. The observed irrigation amount surpassed consumptive use, and approximately 52 to 69 percent of inflow (precipitation plus irrigation) was lost to surface drainage. Field data showed that significant amounts of irrigation water and rainfall were not effectively used for rice paddy culture. Water quality data indicated that drainage from paddy fields could degrade the recipient water environment. The nutrient balance indicated that significant amounts of nutrients (29.5 percent of total N and 8.6 percent of total P compared to input) were lost through surface drainage. Furthermore, up to half the nutrient losses occurred during nonstorm periods. The study results indicate that inadequate water management influences N and P losses during both storm and nonstorm periods. Proper water management is required to reduce nutrient losses through surface drainage from paddy fields; this includes such measures as minimum irrigation, effective use of rainfall, adoption of proper drainage outlet structures, and minimized forced surface drainage.  相似文献   
994.
ABSTRACT: It is contended that water conservation measures that reduce a water system's net revenues are unlikely to be adopted. Pricing policies that induce conservation can be designed to increase net revenues. Management practices that lead to conservation and pure conservation measures may reduce net revenues; consequently, they are unlikely to be adopted. Recent experience in five southwestern cities supports these contentions. It is argued that the managers of a municipal water enterprise are particularly sensitive to short term variation in revenues. Consequently, to increase the likelihood of the adoption of measures that reduce net revenues it is necessary to remove either the decision to adopt measures that reduce net revenue or the adverse revenue effect from the water enterprise. Finally, to make higher rates for conservation palatable, imaginative use for the funds generated must be developed.  相似文献   
995.
The Sierra Club, which has long fought selected water resource projects that it believes would be environmentally damaging, has come to the conclusion in recent years that much more basic reforms are required in water resources development activities if the demands for environmental quality now evidenced by the American people are to be satisfied. These reforms should not be limited to those that would have a direct effect on the environmental aspects of proposed projects, but also many others long advocated by the economics profession that would have favorable indirect effects. Among the urgent reforms with indirect effects are those involving revision of the procedures used in evaluating proposed projects. These procedures should be revised so that future evaluations will much more accurately reflect the economic and environmental merits of proposed projects. Basic reforms of tax policies are also needed that will eliminate most of the private profit available to those who can persuade the government to increase the value of their land through the construction of water projects. Finally, some additional actions can be taken that will have a direct impact on lessening the adverse environmental impact of water projects beyond the provisions of the National Environmental Policy Act of 1969.  相似文献   
996.
On November 13-14, 2003, a symposium on high-visibility safety belt use enforcement in Raleigh, NC: (a) celebrated the 10th anniversary of North Carolina's Click It or Ticket program; (b) documented current knowledge regarding safety belt use; (c) proposed strategies to increase use further; and (d) discussed research to support these strategies.  相似文献   
997.
大春河小流域水土保持综合治理成效显著,是一个高标准、大规模、好效益的集综合防治、科技推广、试验示范于一体的"精品小流域",为水土流失综合治理与农业产业结构调整起了很好的示范作用。  相似文献   
998.
Questionable accountability: MSF and Sphere in 2003   总被引:1,自引:0,他引:1  
Tong J 《Disasters》2004,28(2):176-189
This article examines the relationship between Médecins Sans Frontières (MSF) and the Sphere Project. Prior to revisiting the concerns MSF had with the project, it looks at factors that give rise to differences between NGOs and cites some reasons for why an organisation such as MSF would not embrace such a project and clarifies some key elements of MSF-style humanitarianism. The author revisits the original concerns and arguments presented by MSF when it decided not to participate beyond assisting with the establishment of technical standards and key indicators for the handbook. This is followed by a critical discussion examining these concerns and counter-criticism with reference to experiences a few years after the inception of Sphere. It concludes with MSF's perceptions and stance regarding Sphere and accountability in 2003.  相似文献   
999.
谈"动态对等"的缺陷   总被引:1,自引:0,他引:1  
美国著名翻译理论家Nida提出的"动态对等"原则是对翻译理论界的一大贡献.笔者在承认这个原则的同时,从它概念的几个关键词入手,指出这个概念中几个值得商榷的地方,认为它的理论基础不牢靠,并分析了它所忽视的翻译所涉及的几个要素,由此表明,翻译这种涉及到许多因素的复杂活动不能依靠一种理论来指导.  相似文献   
1000.
The regulation and management of stream ecosystems worldwide have led to irreversible loss of wildlife species. Due to recent scrutiny of water policy and dam feasibility, there is an urgent need for fundamental research on the biotic integrity of streams and riparian zones. Although riverine turtles rely on stream and riparian zones to complete their life cycle, are vital producers and consumers, and are declining worldwide, they have received relatively little attention. I review the literature on the impacts of contemporary stream management on freshwater turtles. Specifically, I summarize and discuss 10 distinct practices that produce five potential biological repercussions. I then focus on the often-overlooked use of riparian zones by freshwater turtles, calculate a biologically determined riparian width, and offer recommendations for ecosystem management. Migration data were summarized on 10 species from eight US states and four countries. A riparian zone encompassing the majority of freshwater turtle migrations would need to span 150 m from the stream edge. Freshwater turtles primarily chose high, open sandy habitats to nest. Nests in North America contained eggs and hatchlings during April through September and often through the winter. In addition, freshwater turtles utilized diverse riparian habitats for feeding, nesting, and overwintering. Additional documentation of stream and riparian habitat use by turtles is needed.  相似文献   
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