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The aim of this study was to provide policy-makers and waste management planners with information about how recycling programs affect the quantities of specific materials recycled and disposed of. Two questions were addressed: which factors influence household waste generation and pathways? and how reliable are official waste data? Household waste flows were studied in 35 Swedish municipalities, and a wide variation in the amount of waste per capita was observed. When evaluating the effect of different waste collection policies, it was found to be important to identify site-specific factors influencing waste generation. Eleven municipal variables were investigated in an attempt to explain the variation. The amount of household waste per resident was higher in populous municipalities and when net commuting was positive. Property-close collection of dry recyclables led to increased delivery of sorted metal, plastic and paper packaging. No difference was seen in the amount of separated recyclables per capita when weight-based billing for the collection of residual waste was applied, but the amount of residual waste was lower. Sixteen sources of error in official waste statistics were identified and the results of the study emphasize the importance of reliable waste generation and composition data to underpin waste management policies.  相似文献   
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The atmosphere remains the major source of mercuryin Swedish ecosystems. Since the late eighties,atmospheric emissions of mercury have drasticallydecreased in Europe. Wet deposition of mercury hasdecreased over the last decade but still exhibitsa clear south-to-north gradient, greatlyinfluenced by source areas in northern and centralEurope. The decreases in emissions can beattributed to both direct measures to close knownpoint sources and a declining economy and energyconsumption in many East European countries.Further reductions of mercury emissions willrequire that other source categories such asindirect emissions from mercury-containingproducts and crematories are be considered.  相似文献   
186.
Remediation of recalcitrant compounds at sites with high concentrations of volatile organic compounds (VOCs) or nonaqueous‐phase liquids (NAPLs) can present significant technical and financial (long‐term) risk for stakeholders. Until recently, however, sustainability has not been included as a significant factor to be considered in the feasibility and risk evaluation for remediation technologies. The authors present a framework for which sustainability can be incorporated into the remediation selection criteria focusing specifically on off‐gas treatment selection for soil vapor extraction (SVE) remediation technology. SVE is generally considered an old and standard approach to in situ remediation of soils at a contaminated site. The focus on off‐gas treatment technology selection in this article allows for more in‐depth analysis of the feasibility evaluation process and how sustainable practices might influence the process. SVE is more commonly employed for recovery of VOCs from soils than other technologies and generally employs granular activated carbon (GAC), catalytic, or thermal oxidation, or an emerging alternative technology known as cryogenic‐compression and condensation combined with regenerative adsorption (C3–Technology). Of particular challenge to the off‐gas treatment selection process is the potential variety of chemical constituents and concentrations changing over time. Guidance is available regarding selection of off‐gas treatment technology (Air Force Center for Environmental Excellence, 1996; U.S. Environmental Protection Agency, 2006). However, there are common shortcomings of off‐gas treatment technology guidance and applications; practitioners have rarely considered sustainability and environmental impact of off‐gas treatment technology selection. This evaluation includes consideration of environmental sustainability in the selection of off‐gas treatment technologies and a region‐specific (Los Angeles, California) cost per pound and time of remediation comparisons between GAC, thermal oxidation, and C3–Technology. © 2008 Wiley Periodicals, Inc.  相似文献   
187.
In forest soils on calcareous parent material, carbonate is a key component that influences both chemical and physical soil properties and thus fertility and productivity. At low organic carbon contents, it is difficult to distinguish between organic and inorganic carbon, e.g. carbonates, in soils. The common gas-volumetric method to determine carbonate has a number of disadvantages. We hypothesize that a combination of two spectroscopic methods, which account for different forms of carbonate, can be used to model soil carbonate in our region. Fourier transform mid-infrared spectroscopy was combined with X-ray diffraction to develop a model based on partial least squares regression. Results of the gas-volumetric Scheibler method were corrected for the calcite/dolomite ratio. The best model performance was achieved when we combined the two analytical methods using four principal components. The root mean squared error of prediction decreased from 13.07 to 11.57, while full cross-validation explained 94.5 % of the variance of the carbonate content. This is the first time that a combination of the proposed methods has been used to predict carbonate in forest soils, offering a simple method to precisely estimate soil carbonate contents while increasing accuracy in comparison with spectroscopic approaches proposed earlier. This approach has the potential to complement or substitute gas-volumetric methods, specifically in study areas with low soil heterogeneity and similar parent material or in long-term monitoring by consecutive sampling.  相似文献   
188.
In several countries, older drivers are disproportionately involved in fatal road traffic crashes (RTCs) for various reasons. This study maps the circumstances of occurrence of crashes involving older drivers that are fatal to either them or other road users and highlights differences between them. Sweden’s national in-depth studies of fatal RTCs archive was used and focus was placed on crashes in which a driver aged 65 years or older was involved between 2002 and 2004 (n = 197). Thirteen driver and crash characteristics were analyzed simultaneously and typical crash patterns (classes) were highlighted. For each pattern, the proportions of crashes fatal to the older driver vs. to someone else were compared. Four patterns were identified: (1) crashes on low-speed stretches, involving left turn and intersections; (2) crashes involving very old drivers and older vehicles, (3) rear-end collisions on high-speed stretches; and (4) head-on and single-vehicle crashes in rural areas. Older drivers dying in the crash were over-represented in classes 2 and 4. The study shows that when older drivers are involved in fatal RTCs, they are often the ones who die (60%). Typical circumstances surrounding their involvement include manoeuvring difficulties, fast-moving traffic, and colliding in an old vehicle. Preventing fatal RTCs involving older drivers requires not only age-specific but also general measures.  相似文献   
189.
In public debates, agricultural biotechnology is almost invariably discussed as a potential threat to the environment and to human health. Without downplaying the risks associated with this technology we emphasize that if properly regulated, it can be a forceful tool to solve environmental problems and promote human health. Agricultural biotechnology can reduce environmental problems in at least three ways: it can diminish the need for environmentally damaging agricultural practices such as pesticides, fertilizers, tillage, and irrigation. It can reduce the land area needed for agriculture, thus reducing the CO2 effect of agriculture and improving biodiversity. It can produce energy in a CO2-neutral way (especially if new technologies involving the cultivation of microalgae become successful). Furthermore, agricultural biotechnology can have positive effects on human health by decreasing occupational and dietary exposure to pesticides, improving the nutritional value of food, and producing pharmaceuticals more efficiently. We argue that those who wish to give high priority to environmental goals cannot afford any longer to be mere onlookers while others decide the future directions of agricultural biotechnology.  相似文献   
190.
Climate change is an important new challenge for local authorities. This study analyses the potential for using the Swedish mandatory process for risk and vulnerability analysis (RVA) as a vehicle to improve local climate adaptation work. An advantage with RVA is its comprehensive approach in dealing with all relevant threats and all vital functions of society. In order to test the applicability of incorporating climate adaptation into RVA, we studied practical experiences from three Swedish municipalities. In all municipalities, a pre-study to identify relevant climate-induced events was performed. In one municipality, this was followed by a more detailed analysis of the potential impacts of these events on the functions of the various administrations and companies within the local authority. Problems identified in successful integration of climate change into the municipal RVA process were lack of sufficient knowledge to identify the impacts of climate change on the level of the respective specialist or district administration and lack of resources to perform the analysis. There were also some difficulties in including a long-term perspective relevant for climate adaptation into RVA, which usually focuses on current threats. A positive outcome was that work on extreme climate events in RVA provided a traceable method to identify events with a potentially great impact on the function of local society and results that could be fed into other ongoing processes, such as spatial planning and housing plans.  相似文献   
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