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31.
In Sweden there is a strong tradition of using nature areas for outdoor recreation. This paper reports on a study which explored preferences and willingness to pay for outdoor recreation close to home (≤100 km away from home and ≤24 hours stay at a recreation site) using the contingent valuation method. The data originated from a mail survey that involved Swedish residents who were randomly selected from a national register. An ordinary least squares regression model was used to account for factors influencing willingness to pay. The results showed that approximately 50% of the respondents used nature areas close to their home for recreation and their average frequency of visits to these areas was 74 times annually. Areas dominated by forests were the most preferred, followed by water. The respondents were willing to pay approximately 7200 SEK (US$1080) annually. Their willingness to pay was influenced by factors such as type of nature area, distance to and time spent at the recreation site and income. The results provide one input to the land use planning process by considering the demand for nature-based outdoor recreation close to home.  相似文献   
32.
Particle density is an important physical property of atmospheric particles.The information on high time-resolution size-resolved particle density is essential for understanding the atmospheric physical and chemical aging processes of aerosols particles.In the present study,a centrifugal particle mass analyzer(CPMA) combined with a differential mobility analyzer(DMA) was deployed to determine the size-resolved effective density of 50 to 350 nm particles at a rural site of Beijing during summer 2016.The measured particle effective densities decreased with increasing particle sizes and ranged from 1.43 to 1.55 g/cm~3,on average.The effective particle density distributions were dominated by a mode peaked at around 1.5 g/cm~3 for 50 to350 nm particles.Extra modes with peaks at 1.0,0.8,and 0.6 g/cm3 for 150,240,and 350 nm particles,which might be freshly emitted soot particles,were observed during intensive primary emissions episodes.The particle effective densities showed a diurnal variation pattern,with higher values during daytime.A case study showed that the effective density of Aitken mode particles during the new particle formation(NPF) event decreased considerably,indicating the significant contribution of organics to new particle growth.  相似文献   
33.
During 24 h, water samples were taken for determination of a number of key parameters in a water system containing high concentrations of FeII at circumneutral pH. None of the major constituents (Ca, Mg, Na, K and sulfate) showed diurnal variations, while dissolved oxygen and pH increased during the night. This increase could entirely be explained by the decrease in water temperature. However, the concentration of FeII slightly increased at constant concentration of total Fe during the night, opposite to earlier observations in other systems where the presence of FeII was shown to be controlled by photoreduction. Nocturnal peaks of FeII have also been observed in other systems with high iron concentrations, however, at acidic pH, but without obvious explanation. The mechanisms for this process therefore need further investigation.  相似文献   
34.
While strengthening public–private interplay is expected to improve the climate profile of urban planning in terms of mitigation and adaptation, less is known about the practice of such new interactive modes of governing. The paper critically examines the role, benefits and limitations of extended public–private interplay in developing a new housing district in Sweden. The developer dialogue between municipal officials and property developers confirms mutual interests, shared understandings and the added value of interacting. However, the closer the dialogue comes to settling agreements, the more difficult it gets for municipal officials to steer the process and its outcomes in favor of climate proofing. Complications with adapting to the new interactive setting means that municipal officials balance between acting as facilitators and/or regulators and property developers between acting as partners, competitors and/or defenders. Refining steering-strategies for sustaining commitments and securing formal agreements are pertinent for using public–private interplay to climate-proof urban planning.  相似文献   
35.
Though managing vulnerabilities posed by climate change calls for effective strategies and measures, its challenges have hitherto not been fully understood. In Sweden, municipalities have recently started incorporating vulnerability management into their political and administrative agendas. This study discusses such experiences and explores how institutional determinants may influence adaptive capacity within a local case study area, to illustrate emerging challenges and opportunities for Swedish municipalities in managing climate vulnerabilities. Specifically, formal institutional structure and the use of knowledge are analysed, concluding that vulnerability management often is focused on technical and reactive fixes, due to limited co-operation between local sector organisations, lack of local co-ordination, and an absence of methods and traditions to build institutional knowledge. Even so, opportunities, such as a high capacity to examine risks to technical systems and important establishments which in turn facilitates protection of technical infrastructure exposed to climate variability and change, also exist.  相似文献   
36.
Local government is attributed a vital role in climate-change adaptation. Previous studies contend that conflicting priorities, insufficient institutional incentives and knowledge of risks, and inadequate resources all impede local climate adaptation. Though the importance of local political support in enabling climate adaptation is widely acknowledged, the views of local politicians have rarely been analysed. Drawing on semi-structured interviews with local politicians in Sweden, we explore what affects their engagement in climate adaptation. The study claims that climate adaptation contrary to mitigation is not viewed as political beyond directing attention and sanctioning guidelines set by officials. A limited number of interviewees claim a more strategic political role in adaptation. The combined effect of institutional incentives (e.g. fragmented national guidelines, unappealing goals, and lack of funding), relative weight in local politics, and ability to exercise political leadership (e.g. campaign value, public and media pressure, and lack of ideology) is perceived as too insignificant to trigger strong political engagement. In less-populous municipalities, adaptive measures were highly valued for demonstrating political action.  相似文献   
37.
Between 1996 and 2002, the Swedish import of so-called yellow waste for energy recovery increased. The import mainly consisted of separated wood waste and mixes of used wood and paper and/or plastics that was combusted in district heat production plants (DHPPs). Some mixed waste was imported to waste incineration plants for energy recovery (10% of the import of yellow waste for energy recovery in 2002). The import came primarily from Germany, the Netherlands, Norway, Denmark and Finland. We identified six underlying driving forces for this recent increase of imported waste which are outlined and their interactive issues discussed. --The energy system infrastructure, which enables high energy recovery in Sweden. --The energy taxation, where high Swedish taxes on fossil fuels make relatively expensive solid biofuels the main alternative for base load production of district heat. --The quality of the waste-derived fuels, which has been higher in the exporting countries than in Sweden. --The bans on landfilling within Europe and the shortage of waste treatment capacity. --Taxes on waste management in Europe. --Gate fee differences between exporting countries and Sweden. In the future, the overall strength of these driving forces will probably be weakened. A Swedish tax on waste incineration is being investigated. In other European countries, the ambition to reach the Kyoto targets and increase the renewable electricity production could improve the competitiveness of waste-derived fuels in comparison with fossil fuels. Swedish DHPPs using waste-derived fuels will experience higher costs after the Waste Incineration Directive is fully implemented. The uncertainty about European waste generation and treatment capacity, however, might have a large influence on the future gate fees and thus also on the yellow waste import into Sweden.  相似文献   
38.
As part of a larger research effort, the empirical basis for this note is responses to four out of many questions in a mailed survey, which primarily focused on national environmental objectives in Sweden. The results show that out of eight broad areas for use of tax money, five-including environment-are rated as important by over 90% of the respondents. Respondents appear to be less willing to discriminate between different issues covered by national environmental objectives, as all of these are rated as important by more than 80% of the respondents. The function of the ozone layer is an example of an environmental issue where the knowledge among people is relatively high, while this is not the case when it comes to the amount of pesticides used in agriculture. The results also show less support for actions at the individual level to improve the environment, as compared to support for actions taken by society at large through, e.g., technological improvement or policy intervention.  相似文献   
39.
This paper briefly describes waste treatment trends in Sweden and describes an example of state-of-the-art treatment in a local integrated waste treatment system (Bor?s). The focus is on treatment of household waste, to illustrate what can be done to establish a sustainable waste treatment system with high recovery of materials and energy. The various processes have resulted in a low amount of landfilled household waste, and high proportions of recovered energy and materials. Heat, electricity, vehicle fuel and fertilizers, metals and construction materials are recovered from the local waste in Bor?s, with less than 4% of domestic waste being sent to landfill.  相似文献   
40.
Several roadside soil samples were collected at two field sites in Sweden. They were analysed for total elemental content (using both ICP-MS and XRF) and stable lead isotopes. Extraction with deicing salt solution and sequential extraction were performed in order to elucidate the potential mobility due to the use of deicing agents. The total concentrations of elements, especially lead, have decreased and lead is presently almost at background concentrations (15-51 ppm for surface samples). However, the isotopic signature indicates that old gasoline lead still is left at the site constructed prior to 1975. The field site constructed in 1992 showed, however, no 206Pb/207Pb ratio below 1.14. Only minor amounts were leached using deicing salt solutions; for lead only 0.29%, on average, was extracted indicating that the mobile fraction already was released. Sequential extraction indicated that lead mainly was associated with reducible (34.4%) and oxidisable (35.4%) fractions. Exchangable and acid soluble fractions contained 20.3% while 10.0% was found in the residual fraction. The salt extraction released, however, very low concentrations indicating that most in fraction 1 is acid soluble (e.g. carbonates). Tungsten was also found at high concentrations indicating a possible impact from studded tires. For tungsten the following composition was obtained: residual (48.0%) > oxidisable (47.6%) > reducible (3.3%) > exchangeable/acid soluble (1.1%). From the isotopic studies it was also suggested that the order for incorporating anthropogenic lead into soils is exchangeable/carbonates > (hydr)oxides > organic matter > residual. The multivariate technique principal component analysis (PCA) seems promising for evaluating large sequential extraction datasets.  相似文献   
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