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This article presents Swedish economy‐wide material flow accounts for the period 1987‐1998. It also shows possibilities for enhancing the international comparability of aggregated data on material use, by distinguishing between materials used for consumption and export purposes. The direct material input (DMI) is used as an aggregate measure to estimate the amounts of natural resources (except water and air) that are taken from nature into the economy within a year, including imports to and production within the region in question. The division of materials used for consumption and export purposes avoids double counting trade flows when DMI is applied to a group of countries. The annual DMI in Sweden for 1997‐1998, including production and imports, amounts to 24 to 27 metric tons per capita (t/c). The fossil fuel input varies only slightly over the period, from 3.2 t/c in 1991 to 3.6 t/c in 1996, a level deemed unsustainable by the Swedish Environmental Protection Agency. The input of renewable raw materials varies between 8 and 9 t/c. Ores and minerals vary between 11 and 15 t/c. The DMI puts Sweden above estimates made for Germany, the United States, and Japan and in the same range as the Netherlands. The differences in these values can mainly be explained by the relative importance of exports as compared to the size of the economy and by the variation in system boundaries for the data on natural resources. The system boundaries and data sources for natural resources need to be further defined to make the measures fully comparable. Around 5 t/c is exported, whereas the rest, around 20 t/c, is national consumption. The aggregate direct material consumption (DMC), which is the DMI minus exports, communicates the magnitude of resource use. Comparisons of the input with solid waste statistics indicate that quantity of waste (excluding mining waste) in Sweden is equal to about 10% relative of the total resource use. Material collected for recycling by the waste management system is equal to about 5% of the amount of virgin resources brought into society each year.  相似文献   
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Given the apparently unbridgeable divide that has developed between the 25 odd countries that grow and trade GM crops and the evolving EU regulatory hurdles, it may be time to consider alternative strategies for realizing a global market for agricultural products. Africa is one area of the world where the battle over GM agriculture is being played out, yet it is the continent where GM could have the greatest positive impact. Numerous African nations, given their long‐standing trade connections to European nations, fear that allowing the commercialization of GM crops could lead to comingling of GM and conventional products and, hence, the loss of export opportunities to the EU. These are legitimate concerns. One potential solution that warrants serious consideration would be to establish a pool of funds that could be accessed by African agricultural commodity exporters in instances where exports to Europe are rejected. A production levy could be imposed in leading industrial adopting nations (i.e., Australia, Canada and the United States). The revenue raised would provide an endowment fund that could be used to offset the costs arising from import refusals. African‐sourced shipments rejected by the EU will most certainly have alternate markets, but could receive a reduced price or incur higher costs associated with serving alternate markets. The intent of the fund would be to compensate for the real difference between the net returns contracted with European importers and the final market price received. This article examines the feasibility of establishing such a fund and discusses the funding options.  相似文献   
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This paper analyses the effect of international trade, environmental performance and agglomeration externalities on CO2 emissions arising from goods transport. It is an indicator that could be used for monitoring progress on the integration of the principles of sustainable transport into national policies. Firstly, we calculate a global transport emissions indicator using existing CO2 emission data. Secondly, given that sea transport is on average less polluting than terrestrial and air transport with regards to greenhouse gas emissions, we calculate a trade-weighted distance indicator that allows for the relative growth of maritime exports. Thirdly, we analyse the relationship between trade and global transport emissions based on existing environmental performance levels by examining both a narrow and a broad environmental performance indicator. Lastly, we examine the role of agglomeration externalities. Comparing different regions within Spain and their trading partners over the period 2000–2008, we are able to plot two different shapes to represent the relationship between trade and global transport emissions, one of which is an inverted-U shape that represents trade with trading partners with a lower environmental performance. Our results show that environmental performance reduces trade-related global transport emissions. Negative externalities for the environment derived from transport facilities agglomeration co-exist too, although these might be partially offset by national regulations that ensure commitment towards a clean environment.  相似文献   
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The current surveillance protocol for Karnal bunt of wheat in most countries, including the USA, European Union (EU), and Australia, involves the tentative identification of the spores based on morphology followed by a molecular analysis. Germination of spores is required for confirmation which incurs a delay of about two weeks, which is highly unsatisfactory in a quarantine situation. A two-step PCR protocol using FRET probes for the direct detection and identification of Tilletia indica from a very few number of spores (≤10) is presented. The protocol involves amplification of the ITS1 DNA segment in the highly repeated rDNA unit from any Tilletia species, followed by FRET analysis to detect and unequivocably distinguish T. indica and the closely related T. walkeri. This rapid, highly sensitive, fluorescent molecular tool is species-specific, and could supersede the conventional microscopic diagnosis used in a quarantine surveillance protocol for Karnal bunt which is often confounded by overlapping morphological characters of closely related species.  相似文献   
5.
The nitrogen (N) budget was developed for Jiulong River Watershed (JRW), an agricultural watershed in a warm and humid area of southeast China. Water quality monitoring, field surveys, modelling and GIS techniques were applied to estimate N flux of atmospheric deposition, mineralization, runoff, denitrification, and ammonia volatilization. Over the whole watershed, fertilizers, import of animal feeds, biotic fixation, mineralization and atmospheric deposition contributed 67.1%, 16.5%, 2.1%, 4.9% and 9.5%, respectively, of total N input (129.3 kg N ha−1 year−1). Runoff, sale of production, denitrification, and ammonia volatilization contributed 7.3%, 24.4%, 10.5% and 57.8% of total N output (72.9 kg N ha−1 year−1), respectively. The N budget for the JRW suggested that more than 50% of the N input was lost to the environment, and about 14% was discharged as riverine N, which indicated that agricultural and human activities in the watershed substantially impacted the estuary and coastal water quality, and so altered the N biogeochemistry process.  相似文献   
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Understanding flows of resource-rich electrical and electronic equipment throughout its life cycle is increasingly important in the development of global circular economies, reflected by heavy legislative focuses on waste prevention and resource use efficiency. This research facilitates broader material flow analysis by characterizing flows of professional IT equipment within the Republic of Ireland, emphasizing the flow of legal exports for the purposes of refurbishment and reuse. The analysis of transboundary movement of non-waste used equipment contributes to a less often measured, but influential, facet of material flows. Eight key exporters of used equipment, comprising original equipment manufacturers, information technology asset disposition companies, and waste treatment facilities, were interviewed to characterize the sector, map the flow of materials, and identify gaps in existing reporting. Interviewed organizations declared exports of used equipment by category using a voluntary declaration form. Two key flows were identified representing currently unreported and unmeasured flows of non-waste professional equipment. A total of 441,261 units of equipment were declared to be exported for reuse from the Republic of Ireland through these previously unmeasured flows in 2019. Product keys developed by United Nations University were used to estimate the weight of total units exported as approximately 576 metric tons, amounting to an additional approximately 9% of the weight of IT equipment collected in the Republic of Ireland in 2018, or 0.1 kg per inhabitant. These quantifications of IT equipment exported for reuse will be a key component of future material flow analyses in the development of a circular economy.  相似文献   
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