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21.
Global greenhouse gas emissions from air travel (GHG-A) are on the rise, and projections point towards a rapid growth in the coming decades. This study aims to examine how local government (cities), addresses GHG-A in their Sustainable Energy Action Plans (SEAP). To fulfil this aim, over 200 SEAPs were analysed focusing on three issues: (1) Treatment of GHG-A in local emissions inventories; (2) Policy initiatives within this domain; and (3) The cities’ perceptions of the conflicts of interests. Results showed that more than half of the cities acknowledge the challenge of GHG-A, around one third include GHG-A in their emissions inventories, and more than one quarter have initiated policy interventions. To categorise these interventions, we have added a mode ‘governing by agenda setting’ to an existing analytical framework, ‘Modes of governing’. With their authority limited to the local setting, this mode of governing is a common channel for cities to push changes at higher levels.  相似文献   
22.
In order to control and reduce fall-related injuries, particularly among women over the age of 55, a safety management and falls prevention campaign was structured and implemented during 2006–2007 in the small industrial town of Södertälje, Sweden. A local campaign was launched to recruit falls prevention agents, to inform key target groups in the local community, and to educate older people about fall risks. A survey showed that the campaign had a greater impact among professionals with a special relation to fall risk than among the general population. Medical records were used in the evaluation of the outcomes. The results show that between 2005 and 2007 there was a drop of fractures related to falls in the council: an overall drop of 16.7% in the population; among men 55 or older a drop of 12%, among women 55 or older a drop of 15%, among home-dwelling women 55 or older a drop of 5.7% and among women in special accommodation a drop of 44.4%. Expressed in terms of years lost to disability (YLD), the overall drop in hip fractures treated at the local hospital between 2005 and 2007 was 48%. A comparison with National medical records for the same period shows the drop for the intervention area to be much larger than that for Sweden as a whole, although the effect was not statistically significant. The study demonstrates the advantages of a broad, community-based approach to injury prevention.  相似文献   
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Because of the dynamic nature of many managed habitats, proper evaluation of conservation efforts calls for models that take into account both spatial and temporal habitat dynamics. We develop a metapopulation model for successional-type systems, in which habitat quality changes over time in a predictable fashion. The occupancy and recruitment of the predatory saproxylic (dependent on dead wood) beetle Harminius undulatus was studied in a managed boreal forest landscape, covering 24,449 ha, in central Sweden. In a first step, we analyzed the beetle's occupancy pattern in relation to stand characteristics, and the amounts of present and past habitat in the surrounding landscape. Managed forest is suitable habitat when > or =60 years old, and immediately after cutting, but not between the ages of 10 and 60 years. The observed occupancy of H. undulatus was positively correlated with the stand's age as habitat. We used a metapopulation model to predict the current probability of occurrence in each forest stand, given the spatiotemporal distribution of suitable forest stands during the last 50 years. Metapopulation parameters were estimated by matching predicted spatial distributions with observed spatial distributions. The model predicted observed spatial distributions better than a similar model that assumed constant habitat quality of each forest stand. Thus, metapopulation models for successional-type systems, such as dead wood dependent organisms in managed forest landscapes, should include habitat dynamics. An estimated 82% of the landscape-wide recruitment took place in managed stands, which covered 87% of the forest area, in comparison with 18% in unmanaged stands, which covered 13% of the forest area. Among the managed stand types, > or =60-year-old stands and 3-7-year-old clear-cuttings contributed to 79% of the total recruitment while 8-59-year-old stands only contributed 3%. The results suggest the following guidelines to improve conditions for H. undulatus and other species with similar habitat requirements: (1) the proportion of the landscape constituted by younger stands should not be allowed to grow too large, (2) the rotation period of managed stands should not be allowed to be too short, and (3) dead wood should be retained and created at final cutting.  相似文献   
25.
Lindell MJ  Bremle G  Broberg O  Larsson P 《Ambio》2001,30(8):545-551
Lake V?ttern in southern Sweden is a large oligotrophic lake with high surface to catchment area ratio (ca. 0.4) and a water residence time of 60 years. The lake combines sensitivity to atmospheric POP-pollution with general susceptibility for effects of POPs and slow concentration decline. Time series, from the 1960s until 1996, of PCBs and DDT in fish and data on TCDD in sediment of L. V?ttern are presented and compared to other large lakes. The long time dataset of POPs in Arctic char (Salvelinus salvelinus) shows a significant annual decline of about 5% for PCBs and 13% for DDT. These rates are in agreement with other studies. Nutrients as well as biological effects and factors affecting the fate of POPs in oligotrophic lakes with long residence times are discussed. We propose that oligotrophic clear lakes are important ecosystems for monitoring POPs in biota.  相似文献   
26.
The levels of persistent, lipophilic pollutants in different organs and body-fluids of birds are governed by partitioning, i.e. the levels are correlated. This implies that it may be possible to estimate the total body-burden of chlorinated hydrocarbons, without sacrificing the animals, by examining the levels in secretory fluid. This hypothesis was tested on the goosander, a fish-eating waterfowl. We found that levels of PCB and DDE in secretions from the uropyginal gland were linearly related to levels in the breast muscle. Thus, by estimating the amounts of persistent pollutants in water-repellent secretions, the total body-burden could be calculated.  相似文献   
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Objective: Norway introduced a “Vision Zero” strategy in 2001, using multiple approaches, aiming toward a future in which no one will be killed or seriously injured in road traffic crashes (RTCs). Official statistics show that the number of fatally injured road users has declined substantially from 341 deaths in 2000 to 117 in 2015. In-depth crash investigations of all fatal RTCs started in Norway in 2005. The aim of this study was to investigate whether fatal crash characteristics, vehicle safety features, and prevalence of drugs and/or alcohol among fatally injured drivers and riders has changed during 2005–2015, accompanying the reduction in road fatalities.

Methods: Data on all car/van drivers and motorcycle/moped riders fatally injured in RTCs during 2005–2015 were extracted from Norwegian road traffic crash registries and combined with forensic toxicology data.

Results: The proportion of cars and motorcycles with antilock braking systems and cars with electronic stability control, increased significantly during the study period. The prevalence of nonuse of seat belts/helmets and speeding declined among both fatally injured drivers and riders. In addition, the prevalence of alcohol declined, though no significant change in the total prevalence of other substances was noted.

Conclusion: The observed changes toward more safety installations in cars and motorcycles and lower prevalence of driver-related risk factors like alcohol use, speeding, and nonuse of seat belts/helmets among fatally injured drivers/riders may have contributed to the decrease in road traffic deaths.  相似文献   

29.
Metal recovery is an essential part of the recycling of hybrid electric vehicle battery waste and the first step in a hydrometallurgical treatment is dissolution of the solid material. The properties of separated battery electrode materials were investigated. Focus was put on both the solid waste and then the dissolution behaviour. The cathode contains metallic nickel that remains undissolved when utilizing non-oxidizing conditions such as hydrochloric or sulphuric acid in combination with a low oxygen atmosphere. In these conditions the cathode active electrode material is fully dissolved. Not dissolving the nickel metal saves up to 37% of the acid consumption for the cathode electrode material. In the commonly used case of oxidizing conditions the nickel metal dissolves and a cobalt-rich phase remains undissolved from the cathode active material. For the anode material a complete and rapid dissolution can be achieved at mild conditions with hydrochloric, nitric or sulphuric acid. Optimal parameters for all cases of dissolution was pH 1 with a reaction time of approximately ?20,000 s.  相似文献   
30.
A naturally contaminated sediment was partially extracted with selective supercritical fluid extraction (SFE) to remove a fraction of supposedly bioavailable PCBs from the matrix. Eels (Anguilla anguilla) were cultured in systems with untreated and pre-extracted sediment, respectively, and it was shown that the SFE treatment selectively removed bioavailable PCBs from the sediment, since relative biota-to-sediment accumulation factors (BSAFs) for the eight studied PCB congeners were much lower in the pre-extracted than in the untreated system at the end of the study. Relative BSAF values decreased with about the same relative amount for all eight congeners, independent of the degree of chlorination and the initial concentration in the sediment. The results demonstrate the ability of SFE to selectively remove sediment-bound PCBs that are available for uptake by the eels, thus demonstrating the feasibility of using selective SFE to estimate bioavailability of PCBs in sediments.  相似文献   
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