927 resultados para Upsala, Sweden. Universitet


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Increased atmospheric deposition of inorganic nitrogen (N) may lead to increased leaching of nitrate (NO3-) to surface waters. The mechanisms responsible for, and controls on, this leaching are matters of debate. An experimental N addition has been conducted at Gardsjon, Sweden to determine the magnitude and identify the mechanisms of N leaching from forested catchments within the EU funded project NITREX. The ability of INCA-N, a simple process-based model of catchment N dynamics, to simulate catchment-scale inorganic N dynamics in soil and stream water during the course of the experimental addition is evaluated. Simulations were performed for 1990-2002. Experimental N addition began in 1991. INCA-N was able to successfully reproduce stream and soil water dynamics before and during the experiment. While INCA-N did not correctly simulate the lag between the start of N addition and NO 2 3 breakthrough, the model was able to simulate the state change resulting from increased N deposition. Sensitivity analysis showed that model behaviour was controlled primarily by parameters related to hydrology and vegetation dynamics and secondarily by in-soil processes.

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The Covered Catchment Experiment at Gordsjon is a large scale forest ecosystem manipulation, where acid precipitation was intercepted by a 7000 m(2) plastic roof and replaced by 'clean precipitation' sprinkled below the roof for ten years between 1991 and 2001. The treatment resulted in a strong positive response of runoff quality. The runoff sulphate, inorganic aluminium and base cations decreased, while there was a strong increase in runoff ANC and a moderate increase in pH. The runoff continued to improve over the whole duration of the experiment. The achieved quality was, however, after ten years still considerably worse than estimated pre-industrial runoff at the site. Stable isotopes of sulphur were analysed to study the soil sulphur cycling. At the initial years of the experiment, the desorption of SO4 from the mineral soil appeared to control the runoff SO4 concentration. However, as the experiment proceeded, there was growing evidence that net mineralisation of soil organic sulphur in the humus layer was an additional source of SO4 in runoff. This might provide a challenge to current acidification models. The experiment convincingly demonstrated on a catchment scale, that reduction in acid deposition causes an immediate improvement of surface water quality even at heavily acidified sites. The improvement of the runoff appeared to be largely a result of cation exchange processes in the soil due to decreasing concentrations of the soil solution, while any potential change in soil base saturation seemed to be less important for the runoff chemistry over the short time period of one decade. These findings should be considered when interpreting and extrapolating regional trends in surface water chemistry to the terrestrial parts of ecosystems.

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Inductively coupled plasma mass spectrometry (ICP-MS) was used to investigate changes in trace element concentration in two high resolution sequences of tree rings from central Sweden. Individual annual growth increments from 18002002 to 1930-2002 were sampled from two Scots pine (Pinus sylvestris) trees from the Siljansfors Experimental Forest. The aims of the study were: to test the viability of conventional solution induction ICP-MS as a technique for investigating the multi-elemental chemistry of long tree ring sequences at annual resolution, and, to test this specifically with a view to detecting changes in elemental concentrations of Swedish tree rings contemporary with the major (and relatively proximal) Icelandic eruption of Askja (1875). It was found that despite a time consuming sample preparation process, it was possible to use conventional ICP-MS for multi-elemental analysis of a long sequence of tree rings at annual resolution. Although promising data were produced, no truly conclusive concentration anomaly could be detected in the sequence to indicate the impact of the Askja eruption on environmental chemistry. Overall findings underlined the complexity of the tree/environment interaction and the cautious approach to data interpretation essential for any dendrochemical study. (c) 2006 Elsevier Ltd. All rights reserved.

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The interest in animal welfare and welfare-friendly food products has been increasing in Europe over the last 10 years. The media, highlighting traditional farming methods and food scares such as those related to salmonella, bovine spongiform encephalopathy/variant Creutzfeldt-Jakob disease (BSE) and avian influenza, have brought the methods of animal farming to public attention. Concerns about farm animal welfare are reflected in the increase in the number of vegetarians and vegans and an increase in consumers wishing to purchase food which is more animal welfare-friendly. This paper considers consumers’ attitudes to animal welfare and to marketing practices, such as product labelling, welfare grading systems and food assurance marks using comparative data collected in a survey of around 1500 consumers in each of Great Britain, Italy and Sweden as part of the EU-funded Welfare Quality research project. The findings suggest a need for the provision of improved consumer information on the welfare provenance of food using appropriate product labelling and other methods.

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We used a battery of biomarkers in fish to study the effects of the extensive dredging in Goteborg harbor situated at the river Gota alv estuary, Sweden. Eelpout (Zoarces viviparus) were sampled along a gradient into Goteborg harbor, both before and during the dredging. Biomarker responses in the eelpout before the dredging already indicated that fish in Goteborg harbor are chronically affected by pollutants under normal conditions compared to those in a reference area. However, the results during the dredging activities clearly show that fish were even more affected by remobilized pollutants. Elevated ethoxyresorufin-O-deethylase activities and cytochrome P4501A levels indicated exposure to polycyclic aromatic hydrocarbons. Elevated metallothionein gene expression indicated an increase in metal exposure. An increase in general cell toxicity, measured as a decrease in lysosomal membrane stability, as well as effects on the immune system also could be observed in eelpout sampled during the dredging. The results also suggest that dredging activities in the Gota alv estuary can affect larger parts of the Swedish western coast than originally anticipated. The present study demonstrates that the application of a set of biomarkers is a useful approach in monitoring the impact of anthropogenic activities on aquatic environments.

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The competitiveness of the construction industry is an important issue for many countries as the industry makes up a substantial part of their GDP – about 8% in the UK. A number of competitiveness studies have been undertaken at company, industry and national levels. However, there has been little focus on sustainable competitiveness and the many factors that are involved. This paper addresses that need by investigating what construction industry experts consider to be the most important factors of construction industry competitiveness. It does so by conducting a Delphi survey among industry experts in Finland, Sweden and the UK. A list of 158 factors was compiled from competitiveness reports by institutions such as World Economic Forum and International Institute of Management Development, as well as from explorative workshops in the countries involved in the study. For each of the countries, experts with different perspectives of the industry, including, consultants, contractors and clients, were asked to select their 30 most influential factors. They then ranked their chosen factors in order of importance for the competitiveness of their construction industry. The findings after the first round of the Delphi process underline the complexity of the term competitiveness and the wide range of factors that are considered important contributors to competitiveness. The results also indicate that what are considered to be the most important factors of competitiveness is likely to differ from one country to another.

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The aim of the article is to present and discuss a study in which Finnish, English and Swedish teachers and student teachers described the implications of being a teacher. It is cross-national and consists of multiple case studies. Data were collected through twenty-four focus group dialogues, and 110 teachers/student teachers participated in the study. According to the study, we have found that teachers and student teachers in all three countries promoted pupils’ development of critical thinking, which is another way of saying that they focused on ‘the attitudes and values’ aspect of citizenship education; however, this was most evident in the Finnish and the Swedish focus groups. In England there is a subject emphasis to the professional role, the three countries ranked the topics (the pupils; the subject; the organization; the society; teacher identity; parents) equally, in Finland the teacher role did not appear to be as post modern as in the two other countries.

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Weathering of mine tailings in Adak results in high As concentrations in surface and ground water, sediments, and soil. In spite of the oxic conditions, As-rich surface and ground, water samples indicate As(III) species predominantly (up to 83%). Several microorganisms were isolated from the enrichment cultures that were involved in As cycling. Amongst them was Arsenicicoccus bolidensis - a novel gram-positive, facultatively anaerobic, coccus-shaped actinomycete, which actively reduced As(V) to As(III) in aqueous media. A. bolidensis reduced 0.06-0.20 mM day(-1) As(V). As(V) reduction displays a direct correlation between the initial As(V) concentration, growth rate, and biomass yield. (c) 2006 Elsevier B.V. All rights reserved.

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This paper outlines the main elements of the Thatcherist ideology focusing on the process of centralisation. The implications of this process for British local government and planning are explored. Attention then turns to Sweden with a discussion of the consensus culture and decentralisation policy. Again the implications for planning are pursued with an emphasis on the 'negotiation' style of planning which has emerged in recent years. The concluding section compares the two experiences and notes many similarities notwithstanding the different ideological contexts.

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This paper highlights some communicative and institutional challenges to using ensemble prediction systems (EPS) in operational flood forecasting, warning, and civil protection. Focusing in particular on the Swedish experience, as part of the PREVIEW FP6 project, of applying EPS to operational flood forecasting, the paper draws on a wider set of site visits, interviews, and participant observation with flood forecasting centres and civil protection authorities (CPAs) in Sweden and 15 other European states to reflect on the comparative success of Sweden in enabling CPAs to make operational use of EPS for flood risk management. From that experience, the paper identifies four broader lessons for other countries interested in developing the operational capacity to make, communicate, and use EPS for flood forecasting and civil protection. We conclude that effective training and clear communication of EPS, while clearly necessary, are by no means sufficient to ensure effective use of EPS. Attention must also be given to overcoming the institutional obstacles to their use and to identifying operational choices for which EPS is seen to add value rather than uncertainty to operational decision making by CPAs.

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Lake Bysjön, southern Sweden, has experienced major lake-level lowerings during the Holocene, with one interval about 900014C yr B.P. when water level dropped ca. 7 m and the lake became closed. These changes were not solely due to known changes in radiation budgets or seasonal temperatures. Simulations with a lake-catchment model indicate that, given the actual changes in radiation and temperatures, all the observed lake-level lowerings (including the major lowering at 900014C yr B.P.) could have occurred in response to precipitation changes of <75 mm/yr when winter temperatures were warmer than today. In these circumstances, the reduction of runoff into the lake caused by increased evapotranspiration during the late winter and spring, combined with relatively small changes in precipitation, was sufficient for the lake to become closed. When winter temperatures were colder than today, the reduction in winter runoff related to reduced precipitation was only very slight and insufficient to lower the lake below threshold. In such circumstances, changes in outflow were sufficient to compensate for the combined changes in precipitation and runoff, and lake level therefore remained unchanged.