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491.
The contemporary Asian silver cycle: 1-year stocks and flows 总被引:2,自引:0,他引:2
Jeremiah Johnson Marlen Bertram Kathryn Henderson Julie Jirikowic T. E. Graedel 《Journal of Material Cycles and Waste Management》2005,7(2):93-103
The stocks and flows of silver throughout the Asian economy for 1997 have been quantified, with major flows examined over their entire life cycle, including mining, production, fabrication, and manufacture, product use, and waste management. By compiling the findings of 11 country-level material flow analyses, a regional analysis was created. The reliability and availability of the data varied, with the most confidence given to the earlier life stages and the most uncertainty existing later. Overall, Asia is a net importer of silver, requiring nearly 7000 Mg of silver in 1997. Approximately 2200 Mg Ag are mined, and production waste totals about 640 Mg Ag. The flow of silver into use equals 9900 Mg Ag, with a considerable build-up of 7100 Mg Ag entering in-use stock. Silver waste sent directly to the environment, in addition to landfilled waste, totals 1600 Mg Ag. Much variation exists when examining country-level silver flows on a per capita basis. India and Thailand’s fondness for silver jewelry greatly increases their silver flows into use and in-use stock. Japan’s high overall consumption reflects its high GDP per capita. Regionally, a significant potential exists to tap the silver contained in the in-use stocks and to enhance the recycling rates. 相似文献
492.
Konstantine Drakonakis Katherine Rostkowski Jason Rauch T.E. Graedel R.B. Gordon 《Resources, Conservation and Recycling》2007,49(4):406-420
A detailed inventory shows that an average resident of the City of New Haven depends on a per capita capital stock of 9200 kg/c of iron and 144 kg/c of copper in the city infrastructure, buildings, transportation systems, and equipment. Of the iron stock 28% is in items such as rail cars and ships in ocean trade not permanently within the city, and 22% is devoted to receiving and delivering oil fuel to the city and its surrounding communities. Copper is principally used in the distribution of electric power and in water piping within buildings. The city's 9200 kg/c of iron stock-in-use is less than the 13,000 kg/c national average due to New Haven's lack of heavy industry and relatively small number of large buildings. The 144 kg/c of copper stock-in-use is only 58% of the overall value for the United States, but is comparable to that in cities such as Stockholm, Sweden. Attainment of a level of iron and copper services with contemporary technology in less developed countries to the level enjoyed in New Haven would require consumption of the presently identified world copper resources. 相似文献
493.
In this study critical load functions and target load functions of nitrogen and sulphur deposition with respect to acidity
and minimum base cation to aluminium ratio were calculated with the SAFE model using three different averaging strategies:
(1) averaging based on current forest generation, (2) averaging based on next generation and (3) averaging based on the entire
simulation period. From the results it is evident that although target load calculation and indeed critical load calculation
is straight forward, there is a problem in translating a predicted recovery according to the target load calculation back
to a site-specific condition. We conclude that a policy strategy for emission reductions that ensures recovery, according
to calculated target load functions, is likely to be beneficial from an ecosystem point of view. However, such a strategy
may not be sufficient to achieve actual non-violation of the chemical criteria throughout the seasonal or rotational variations.
To address this issue we propose a method for calculating dynamic critical loads which ensures that the chosen criteria is
not violated. 相似文献
494.
Jason Matus 《Disasters》2007,31(S1):S91-S103
Currently, the pace of recovery in the 'Three Areas' is moving faster than the implementation of the Comprehensive Peace Agreement (CPA). This gap is leading to greater imbalances in income, unsustainable urbanization, overexploitation of the environment and resource based conflict. Unless regulated, the likely result will be chronic poverty and an undermining of the success of the CPA. Agencies must be mindful of how they provide assistance so that they support the CPA. The analysis of food security should take place in the context of a larger political, social and economic analysis of the emerging situation. The least developed areas should be prioritised and interventions should provide benefits to the full range of socioeconomic groups. WFP must identify its role in the wider and integrated response. It should support the emerging peace process and the key reforms. If WFP chooses to consolidate its activities, it will require capable strategic partners. If it chooses to invest more in building the capacity of government and community structures, it must improve its skill base and field presence 相似文献
495.
Examining Hazard Mitigation Within the Context of Public Goods 总被引:1,自引:0,他引:1
Reddy SD 《Environmental management》2000,25(2):129-141
/ This paper presents a case study of an American barrier island devastated by a hurricane to show how it is addressing the free-riding problem and protecting its public goods, thereby contributing to hazard mitigation. It examines hazard mitigation and the free-riding problem within the public goods framework. Free-riding is a term used in the public choice theory and common pool resource literature. It is a term used for describing the actions of rational individuals who freely exploit a collective or public good at the expense of others. Free-riding is a major problem faced by public goods. The problem very frequently occurs in the context of hazard mitigation and coastal resource management. Very little is known about the factors that contribute to the promotion of hazard mitigation. This paper identifies some of the important factors that help local institutions provide and sustain hazard mitigation measures. Theoretical and practical implications for hazards research and disaster management policy are presented. 相似文献
496.
Evaluators frequently cite the absence of effective participation by constituent governments and the need for consensus or even unanimity prior to action as the causes of poor performance by regional resource management institutions. Major governments either will not join the regional institution, will not participate even if legally members, or will exercise a veto over many important management projects.This paper examines the variables that may cause these problems and provides an improved understanding of why rational political actors would act in ways that inhibit the efficient management of resources. Among the principal variables determining participation are expected benefits of collective decisions, perceived losses of autonomy and representation, the number and homogeneity of other participants, decision costs, and the decision rule used to determine actions. Analysis of these factors suggests why consensus and unanimity decision rules are frequently chosen and why participation is usually limited. 相似文献
497.
该文阐述了台湾固体废物的回收利用工作通过立法进行管理固废回收市场运营,通过科技研究为废物综合利用资源化提供了有益借鉴。 相似文献
498.
499.
Edwin D. Bailey 《Journal of the American Water Resources Association》1979,15(3):801-811
ABSTRACT: The Tucson area is totally dependent on ground water, which is in increasingly short supply due to excessive overdrafts. Tucson area waste water treatment plants discharge material quantities of secondary effluent downstream, which is lost to evapotranspiration and recharge of the ground water basin. The city and the four large mining companies who share the common Santa Cruz basin ground water, recognized the common water supply problem and agreed to fund a feasibility study for mining process use of the effluent to partly alleviate the overdraft of ground water. The study analyzed the projected waste water effluent resources, potential mining company demand for waste water effluent and possible interface of an effluent delivery facility with the proposed Central Arizona Project. The effluent resources were analyzed with respect to potential demand. An optimum alignment was selected. An optimum system was detailed through design schematics, amortized cost and finance requirements, and an implementation schedule. It was concluded that a waste water effluent delivery facility could be implemented which would utilize reclaimed effluent in quantities approximating 35 percent of basin overdraft and which would provide revenue for full cost recovery over a 20 year operation period. The mining companies are studying the internal economic impacts of the project. 相似文献
500.
The idea of pre-impact recovery planning has recently been promoted by researchers and practitioners, but very little research has been done to evaluate its effects on disaster recovery. This study compared two jurisdictions — the city of Los Angeles, California and Taichung county in Taiwan — in their recovery from earthquakes. Although the two cases also differ with respect to variables other than the presence of pre-impact recovery plans, the available data suggest that having a pre-impact recovery plan facilitates housing reconstruction and allows local officials to make more effective use of the window of opportunity after disaster to integrate hazard mitigation into the recovery process. 相似文献