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361.
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Many materials currently in use are potentially available to become raw materials for future production if the materials are recycled instead of discarded as solid waste. However, the structure and life-expectancy of these secondary resources have not been sufficiently examined, and comprehensive methods for forecasting the availability of such materials are still lacking. This study presents a method for identifying anthropogenic material stocks in combination with the method of material flow analysis (MFA). The method was applied to copper in Switzerland as an example, with the focus on use in buildings. The exploration concept was a three-step process. First, a MFA identified the relevant stocks within the inventory of the region. Second, these stocks were inventoried through a building stock model and determination of key parameters that were defined by surveying selected buildings and from the literature. Third, the study team developed a dynamic MFA model to describe the copper stocks and flows during the period 1900-2000. The results of the copper stock calculation (in kg capita(-1)) were: buildings 79 +/- 11, infrastructure 107 +/- 25, movables 34 +/- 9, landfills 50 +/- 12. The calibrated model enabled the study team to develop resource and waste management scenarios forecasting waste flows. It is shown that the conversion of buildings into other uses may affect the waste flows significantly. 相似文献
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The prenatal detection of hypoxanthine phosphoribosyltransferase (HPRT, EC 2.4.2.8) deficiency, the Lesch-Nyhan syndrome, during the first trimester of an affected pregnancy through the use of chorionic villus sampling is reported. Quantitation of reaction products formed by villus cell extracts from exogenous hypoxanthine-8-[14C] or adenine-8-[14C] is used in diagnosis. We report the diagnosis of Lesch-Nyhan syndrome using a chorionic villus specimen and confirmation of that diagnosis. In addition, adenosine deaminase (ADA) and purine nucleoside phosphorylase (PNP), enzymes deficient in inherited immune disorders, are detected in chorionic villus samples. These heritable disorders also appear amenable to early prenatal diagnosis. 相似文献
365.
A 34-kilometer reach of the Virgin River, Utah-Arizona-Nevada, was poisoned with rotenone in an attempt to eradicate non-native red shiners ( Cyprinella lutrensis ), a species implicated in the decline of native fish populations in the American West. An error in detoxification resulted in lethal concentrations of piscicide passing through an additional 50 kilometers of stream. We used allozyme electrophoresis to analyze genetic variation among pre- and post-poison samples of endangered Virgin River chubs ( Gila seminuda ). Pre-poison samples indicated a single panmictic population in the river. In contrast, fish subsequently produced through natural recruitment in poisoned reaches exhibited deviations from the original pattern of genetic variation. A genetic bottleneck caused by severe reduction in the number of spawning adults was indicated. The altered pattern persisted 2.5 years post-poisoning, indicating unexpectedly slow recolonization from the unpoisoned reach upstream. Genetic variation among hatchery-produced young was similarly unrepresentative of the original pattern because of the small number of brood fish used in propagation. Because of their small numbers and/or restricted distribution, endangered species are particularly vulnerable to natural or anthropogenic catastrophes. Assessment of the genetic impact of such events is essential but requires that baseline data are available. 相似文献
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Miscanthus for Renewable Energy Generation: European Union Experience and Projections for Illinois 总被引:1,自引:0,他引:1
Heaton Emily A. Long Stephen P. Voigt Thomas B. Jones Michael B. Clifton-Brown John 《Mitigation and Adaptation Strategies for Global Change》2004,9(4):433-451
Mitigation and Adaptation Strategies for Global Change - 相似文献
369.
Thomas Knoke Michael Weber 《Mitigation and Adaptation Strategies for Global Change》2006,11(3):579-605
The study presents a comprehensive methodology for the appraisal of C-stock expansion in existing forests as a forest management
activity according to Art. 3.4 of the Kyoto Protocol. It allows for producer costs of carbon sequestration in forest enterprises
to be derived. The methodology is based on a non-linear programming approach considering economic optimisation as well as
ecological, social and sustainability needs through constraints and risk integration. While introducing further constraints
on carbon stocks, the carbon stored in forest biomass was increased in periodic increments. However, while extending the carbon
stocks, the ecological and social constraints as well as sustainability requirements are not to be violated. Costs were derived
for every additional Mg (Megagrams) of C per ha sequestered in comparison to a baseline management.
Two basic cases were considered: First, a permanent carbon sequestration was assumed. Secondly, a temporary storage of additional
carbon over 10 years was supposed. The potential willingness of buyers of carbon certificates to pay for temporary carbon
sequestration was derived by a financial consideration. We assumed that, for a buyer, the value of a temporary carbon sequestration
certificate would be equivalent to the return on the savings because an investment in technical measures on reduction of carbon
emissions can be postponed. 相似文献
370.
Thomas Tsatsarelis Ioannis Antonopoulos Avraam Karagiannidis George Perkoulidis 《Waste management & research》2007,25(5):417-425
This study presents an assessment of the current status of open dumps in Laconia prefecture of Peloponnese in southern Greece, where all open dumps are targeted for closure by 2008. An extensive field survey was conducted in 2005 to register existing sites in the prefecture. The data collected included the site area and age, waste depth, type of disposed waste, distance from nearest populated area, local geographical features and observed practices of open burning and soil coverage. On the basis of the collected data, a GIS database was developed, and the above parameters were statistically analysed. Subsequently, a decision tool for the restoration of open dumps was implemented, which led to the prioritization of site restorations and specific decisions about appropriate restoration steps for each site. The sites requiring restoration were then further classified using Principal Component Analysis, in order to categorize them into groups suitable for similar restoration work, thus facilitating fund allocation and subsequent restoration project management. 相似文献