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31.
The contemporary copper cycle of Asia   总被引:11,自引:1,他引:10  
A regional stock and flow model for an industrial metal was developed based on the substance-flow framework. Using this model, the contemporary copper cycle of the Asian region was constructed by aggregating country-level production and import and export data for different stages of the copper cycle. The reliability and availability of data were assessed both qualitatively and quantitatively. Asia as a region is a net importer of copper. There is a significant build-up of copper in use at a rate of nearly 3TgCu/year. The per capita generation of copper waste (0.4kgCu/(capita-year)) and the rate of secondary recovery of copper are low compared with Europe and North America. Japan's rates of use, waste generation, and recycling of copper are all much larger than the continental average. A tremendous potential exists in the region to utilize the copper content of the in-use reservoir, and subsequently to enhance copper recycling rates in the future. A set of metrics for the copper cycle is suggested in order to address sustainability issues related to resource policy and the environmental management of copper.  相似文献   
32.
Within the context of a case study of three Asia/Pacific countries' mineral taxation regimes, this article examines the impact of individual fiscal instrucments, and the total fiscal package, on investor risk perceptions, investor returns and government receipts. It shows that under conditions of uncertainty and risk aversion on the part of investors, significant gains in expected government revenues can be achieved without seriously affecting the investors' ex-ante assessments of projects by a judicious selection and mix of fiscal instruments.  相似文献   
33.
Anthropogenic Calcium Particles Observed in Beijing and Qingdao, China   总被引:2,自引:0,他引:2  
Analysis of individual particles collected at Beijing in northern China revealed that particles abundant in calcium (Ca) always constituted a large fraction of mineral particles in the urban atmosphere. The particles were characterized by cubic morphologies. The major mineral element in the particles was Ca and few or no other mineral elements were detected. A large number of the particles were in the range of diameter <1 μm, where common natural mineral particles were rarely detected. The contribution of the Ca particles to the volume of total mineral particles greatly exceeded that of other mineral particles during non-dust-storm periods and was comparable to that during dust-storm periods. Reagent film tests showed that particulate sulfate and nitrate formation on the Ca particles was similar to that on common mineral particles. These results indicate that a large portion of Ca in the atmospheric particulate matter in Beijing was from anthropogenic sources rather than from natural sources, and the anthropogenic Ca particles acted as a significant medium for the formation of sulfate and nitrate. Similar particles were also detected at Qingdao, a coastal city in northern China. Data of a dust storm event showed that Ca-abundant particles from East China arrived there and moved out of the continent, similarly to Asian dust storm particles, suggesting possible contributions of anthropogenic Ca even in Asian dust storm samples in the downstream areas. Therefore, Ca may not be a good indicator of Asian dust from natural sources. However, the Ca particles, due to their unique shapes and elemental compositions, may provide an indicator for the atmospheric dispersion of anthropogenic particulate matters in East Asia.  相似文献   
34.
Small-scale fisheries are important in Laos, where rural people heavily depend upon Mekong River and tributary fish stocks for their livelihoods. Increasing pressures from human exploitation and habitat disturbance, however, have raised serious concerns about the potential depletion of various species. This has led to the establishment of large numbers of Fish Conservation Zones (FCZs) or “no-take” fish sanctuaries in southern Laos based on a “community-based fisheries co-management” framework. This study uses the local ecological knowledge (LEK) of fishers to assess the effectiveness of village-managed FCZs in enhancing fish stocks in the mainstream Mekong River in Khong District, Champasak Province. Focus group interviews about species that are believed to have benefited from different FCZs are compared with parameters such as FCZ area, age, depth, localized gradient, water velocity, and the presence of wetland forests nearby. The results suggest that no one aspect is likely to account for variations in fish stocks; rather, it is the interaction between numerous factors that has the largest impact. Secondly, the results indicate that microhabitat diversity and protection are critical for maintaining and enhancing Mekong fisheries. Deep-water pools are particularly important as dry season refuges for many fish species, and FCZ depth may be the single most important environmental factor affecting the success of FCZs in the Mekong River. FCZs have the most potential to benefit relatively sedentary species, but may also benefit highly migratory species, given the right conditions. This study shows that integrated approaches to stock assessment that employ LEK and scientific fisheries management have considerable potential for improving Mekong capture-fisheries management.  相似文献   
35.
The contemporary Asian silver cycle: 1-year stocks and flows   总被引:2,自引:0,他引:2  
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   
36.
Sustaining Asia's groundwater boom: An overview of issues and evidence   总被引:6,自引:0,他引:6  
This article suggests that Asia’s groundwater socio‐ecology is at an impasse. Rapid growth in groundwater irrigation in South Asia and the North China plains during the period 1970–95 has been the main driver of the agrarian boom in these regions. India, Pakistan, Bangladesh and China account for the bulk of the world’s use of groundwater in agriculture. On the plus side, groundwater development has provided sustenance to agrarian economies and millions of rural livelihoods. On the downside, it has created chronic problems of resource depletion and quality deterioration. While problems of groundwater depletion, pollution and quality deterioration are indeed serious, so are the consequences of the degradation of the resource for those that have come to precariously depend upon groundwater irrigation. Three problems currently afflict groundwater use: depletion due to overdraft; water logging and salinization; and pollution due to agricultural, industrial and other human activity. The pathology of the decline in groundwater socio‐ecology reflects a remarkably similar pattern across regions. The critical issue for Asia now is: what might be done to sustain and revive these groundwater socio‐ecologies vital to the region’s economy? This article reviews a variety of techno‐institutional approaches. However, transposing lessons from the industrialized world uncritically in the Asian context may not work. A more nuanced understanding of the peculiarities of Asia’s groundwater socio‐ecology is needed.  相似文献   
37.
Climate change in Asia: issues and policy options   总被引:1,自引:0,他引:1  
This article provides a brief review of some of the policy issues facing the Asian region with respect to climate change and its economic consequences. The environmental consequences of Asia's economic rise threaten the future growth of the region. Despite recent economic expansion, Asia will be one of the areas of the world most vulnerable to climate change. While Asia currently contributes moderately to greenhouse gas emissions, the potential for increases in emissions is significant. National and regional policy options, including abatement and adaptation, are examined as strategies for tackling the likely effects of climate change. This study recommends that national initiatives that have no 'regrets' properties be a priority area for further research so that they can be implemented as soon as possible. It is envisaged that in the short to medium term, identifiable no regrets policies can be a useful tool for reducing emissions and vulnerability to climate change in developing regions such as Asia.  相似文献   
38.
Environmental education is essential to the success of Agenda 21. Yet currently it is without focus and effectively side-lined. This paper presents the results of preliminary investigations on the environmental attitudes and knowledge of Indian and Filipino primary and secondary school students, and their readiness to engage in pro-environmental behavior that could involve some change in their personal lifestyle. For the most part, environmental education efforts are embedded mainly into various science subjects. The relationship between environmental education and environmental awareness is analyzed to examine whether schools' environmental education could contribute to the shaping of environmental attitudes. A strategy and accompanying methodology for establishing environmental education is supplied.  相似文献   
39.
基于广西防城港市、福建福清市和宁德市的3个滨海核电厂周边γ辐射空气吸收剂量率长时间高频率的连续观测数据,从不同时间尺度进行系统解析.研究发现,在年际尺度上,2014~2020年间宁德嵛山岛站位γ辐射空气吸收剂量率呈现先上升后下降的趋势,与太阳活动的先减弱后增强存在一定的反相位关联;在季节尺度上,2019年度3个站位的观...  相似文献   
40.
Organochlorine pesticides in soils around Guanting Reservoir,China   总被引:3,自引:0,他引:3  
Fifty-six representative samples of topsoil were collected around Guanting Reservoir, which is an important water source for Beijing. Concentrations of the insecticides HCH, DDT, and their metabolites were quantified by use of gas chromatography (GC) with electron capture detection (ECD). Organochlorine pesticides (OCPs) are still present in surface soils in the Guanting area. DDT accounts for about 93% of the total OCP content. Concentrations of α/γ, β/γ, and DDT/DDE are the result not only of historical use, but also of more recent depositions. Statistical analyses, including principal component analysis (PCA) and cluster analysis (CA), revealed associations between concentrations of OCPs and major soil characteristics. Geographical information system (GIS) technology was used to develop maps of the distributions of OCP concentrations. The areas of greatest contamination were primarily in the central part of the study area and were correlated with greater population density, heavier traffic, and more industrial activity.  相似文献   
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