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291.
292.
Feng Wang Jaco Huisman Christina E.M. Meskers Mathias Schluep Ab Stevels Christian Hagelüken 《Waste management (New York, N.Y.)》2012,32(11):2134-2146
E-waste is a complex waste category containing both hazardous and valuable substances. It demands for a cost-efficient treatment system which simultaneously liberates and refines target fractions in an environmentally sound way. In most developing countries there is a lack of systems covering all steps from disposal until final processing due to limited infrastructure and access to technologies and investment. This paper introduces the ‘Best-of-2-Worlds’ philosophy (Bo2W), which provides a network and pragmatic solution for e-waste treatment in emerging economies. It seeks technical and logistic integration of ‘best’ pre-processing in developing countries to manually dismantle e-waste and ‘best’ end-processing to treat hazardous and complex fractions in international state-of-the-art end-processing facilities. A series of dismantling trials was conducted on waste desktop computers, IT equipment, large and small household appliances, in order to compare the environmental and economic performances of the Bo2W philosophy with other conventional recycling scenarios. The assessment showed that the performance of the Bo2W scenario is more eco-efficient than mechanical separation scenarios and other local treatment solutions. For equipment containing substantial hazardous substances, it demands the assistance from domestic legislation for mandatory removal and safe handling of such fractions together with proper financing to cover the costs. Experience from Bo2W pilot projects in China and India highlighted key societal factors influencing successful implementation. These include market size, informal competitors, availability of national e-waste legislation, formal take-back systems, financing and trust between industrial players. The Bo2W philosophy can serve as a pragmatic and environmentally responsible transition before establishment of end-processing facilities in developing countries is made feasible. The executive models of Bo2W should be flexibly differentiated for various countries by adjusting to local conditions related to operational scale, level of centralized operations, dismantling depth, combination with mechanical processing and optimized logistics to international end-processors. 相似文献
293.
Schleyer C 《Environmental management》2004,34(2):281-290
As in many fen land regions in East Germany, long-standing intensive arable farming—enabled by reclamation—has caused soil deterioration and high water runoff in the Schraden region. The more than ten years of economic and political transformation that followed the breakdown of the socialist regime has worsened the situation and even added new problems. The visible consequences are droughts in the summer, waterlogged plots in the spring, and worn-down water management facilities that operate in an uncoordinated or even unauthorized way. Given the local public-good character of some features of the fen land, the common-pool character of the ecosystems intermittently scarce resource water, and the conflicting interests of regional stakeholders, it is argued that the reallocation of property rights over reclamation systems, together with ineffective coordination mechanisms, have caused the physical and institutional failure of the water management system and so impeded appropriate land use.
Note: This version was published online in June 2005 with the cover date of August 2004. 相似文献
294.
In this study we used photographs of tree crowns to test whether the assessment methods for tree defoliation in Switzerland have changed over time. We randomly selected 24 series of slides of Norway spruce with field assessments made between 1986 and 1995. The slides were randomly arranged and assessed by three experts without prior knowledge of the year when the slide was taken or the tree number. Defoliation was assessed using the Swiss reference photo guide. Although the correlations between the field assessments and slide assessments were high (Spearman's rank correlation coefficient ranged between 0.79 and 0.83), we found significant differences between field and slide assessments (4.3 to 9% underprediction by the slide assessors) and between the slide assessments. However, no significant trends in field assessment methods could be detected. When the mean differences between field and slide assessments were subtracted, in some years, field assessors consistently underpredicted (1990, 1992) or overpredicted defoliation (1987, 1991). Defoliation tended to be overpredicted in slides taken against the light, and underpredicted for trees with more than 25% crown overlap. We conclude that slide series can be used to detect changes in assessment methods. However, potential observer bias calls for more objective methods of assessment. 相似文献
295.
Daniel Houle Christian Gagnon Suzanne Couture Alain Kemp 《Water, Air, & Soil Pollution: Focus》2004,4(2-3):247-261
Since 1985, monitoring activities have been conducted in a networkof 43 lakes comprising the Québec portion of the Long-Range Transport of Airborne Pollutants (LRTAP) program. The results to date indicate that Québec lakes generally are responding positively to the generalized decline in precipitation sulfate (SO4 2-), with 40 of the 43 lakes now showing steep declines in SO4 2- concentrations. The drop in SO4 2- was associated with a significant decrease in Ca2+ concentrations in 77% of the lakes (67% for Mg2+ concentrations). Overall, the acid-neutralizing capacity was increasing in 19 lakes and decreasing only in three, while 21 lakes showed no temporal trends. Compared with previous trend studies of the LRTAP-Québec network for the period of 1985–1993, the longer period (1985–1999) shows a clear improvement, with the proportion of lakes that were acidifying changing from 24 to 7% and with the proportion of lakes that were recovering changing from 16 to 35%. These observations suggest that the recent drop in SO4 2- deposition in the northeastern U.S. and eastern Canada was significant enough to allow chemical recovery for a significant proportion of Québec lakes. 相似文献
296.
297.
Angehr GR Siegel J Aucca C Christian DG Pequeño T 《Environmental monitoring and assessment》2002,76(1):69-87
We developed an assessment and monitoring plan for birds in connection with the exploration and potential development of a large natural gas field in the Lower Urubamba drainage of Peru, a project of Shell Prospecting and Development Peru (SPDP). Our objectives were to: (1) inventory the birds in the area, including information on habitat use and abundance, and (2) devise long-term monitoring protocols for birds. We sampled birds through a combination of visual and auditory surveys and mist-netting at 4 well sites and 3 sites along the Urubamba and Camisea rivers. We recorded 420 speciesduring 135 days of field work. We consider the highest prioritiesfor a future monitoring program to be: (1) establish whether edge effects are occurring at well sites, along roads and alongthe planned pipeline route and determine the significance and extent of these effects and (2) assess the impact of increased human access to the area on game and other exploited species. The remoteness of the area, its rugged terrain and dense vegetation and the lack of trained personnel limit the choice of survey and monitoring methods. We recommend use of mist-netting and transects for monitoring edge effects and useof transects for monitoring game and other exploited species. 相似文献
298.
We tested whether the semi-automatic program CROCO can replace visual assessments of slides to detect changes in defoliation assessment methods. We randomly selected a series of slides of 24 Norway spruce trees with 220 field assessments made between 1986 and 1995. The slides had been randomly arranged and assessed by three experts without knowledge of the tree number or the year when the slide was taken. Defoliation scores were computed with CROCO. Each tree had thus three different defoliation scores, field assessments, photo assessments and CROCO scores.CROCO scores were less correlated with the field assessments (Spearmans rank correlation: 0.67) than were the slide assessments with the field assessments (0.79–0.83). However, CROCO was not biased against the field scores, while slide assessments systematically underestimated defoliation.In a multi-variate mixed effect model none of the variables tree overlap, tree visibility and light conditions was significant in explaining differences between slide assessors and CROCO scores. The same model applied for the differences from the field scores yielded significant effects for poor light conditions (CROCO and all assessors), for crown overlap (CROCO and one assessor) and for visibility (one assessor). We conclude, therefore, that CROCO can be used to detect past and future changes in assessment methods without bias if poor quality photographs are avoided. 相似文献
299.
300.
Setting the stage for the review of the international estimate of short-term intake (IESTI) equation
Anke Richter Christian Sieke Hermine Reich Bernadette C. Ossendorp Nicolas Breysse Jason Lutze 《Journal of environmental science and health. Part. B》2018,53(6):343-351
ABSTRACTIn the framework of setting Maximum Residue Limits (MRLs) for pesticides, both chronic and acute health risks to consumers arising from the long-term and short-term dietary exposure to pesticide residues have to be assessed. The current internationally harmonized approach for assessing the acute dietary exposure is based on deterministic methods for calculating the IESTI (International Estimate of Short-Term Intake). Recently, it became apparent that the IESTI approach needs a revision in the light of new scientific and political aspects. The main reasons that require this review were the lack of an international harmonization of the methodology which implies trade barriers as well as difficulties in risk communication concerning the public trust in regulatory systems. The most recent milestone in the scientific debate on a possible revision of the IESTI equation was an international scientific workshop held in Geneva in September 2015. The main objectives of this meeting were the re-evaluation, and where possible, the international harmonization of the input parameters for the IESTI equations as well as the equations themselves. The main recommendations from the workshop were (i) to replace the highest residue and supervised trials median residue with the maximum residue limit (MRL), (ii) to use a standard variability factor of three, (iii) to derive the P97.5 large portion value from the distribution of consumption values of dietary surveys expressed as kg food/kg bw/d, and (iv) to remove the commodity unit weight from the equations. In addition, the application of conversion factors and processing factors was addressed. On the initiative of the (World Health Organization) WHO Collaborating Centre on Chemical Food Safety at the National Institute for Public Health and the Environment (RIVM), the Netherlands, an international working group with members from the French Agency for Food, Environmental and Occupational Health and Safety, France (ANSES), Australian Pesticides and Veterinary Medicines Authority, Australia (APVMA), German Federal Institute for Risk Assessment, Germany (BfR), Chemical Regulation Division, the United Kingdom (CRD), European Food Safety Authority (EFSA), and RIVM, the Netherlands was formed after the IESTI workshop to conduct a comprehensive impact assessment of the proposed changes of the IESTI equations. 相似文献