| 1. |
- Bonnedahl, Jonas, et al.
(författare)
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In search of human-associated bacterial pathogens in Antarctic wildlife : report from six penguin colonies regularly visited by tourists.
- 2005
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Ingår i: Ambio: A Journal of the Human Environment. - : Springer. - 0044-7447 .- 1654-7209. ; 34:6, s. 430-2
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Tidskriftsartikel (refereegranskat)abstract
- We investigated the potential role of Antarctic tourism in the introduction of human-associated pathogens into Antarctic wildlife. We collected and analyzed 233 fecal samples from eight bird species. The samples were collected at six localities on the Antarctic Peninsula, which often is visited by tourists. Every sample was investigated for pathogens of potential human origin: Campylobacter jejuni, Salmonella spp., and Yersina spp. None of these bacteria was found. Our data suggest that the tourism industry so far has achieved its goal of not introducing pathogens into the Antarctic region. There is, however, an urgent need to further investigate the situation in areas closer to permanent Antarctic settlements.
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| 2. |
- Callaghan, TV, et al.
(författare)
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Key findings and extended summaries
- 2004
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Ingår i: Ambio: a Journal of Human Environment. - 0044-7447. ; 33:7, s. 386-392
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Tidskriftsartikel (refereegranskat)
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| 3. |
- Callaghan, Terry V., et al.
(författare)
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Biodiversity, distributions and adaptations of arctic species in the context of environmental change
- 2004
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Ingår i: Ambio: a Journal of Human Environment. - : Royal Swedish Academy of Sciences. - 0044-7447. ; 33:7, s. 404-417
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Forskningsöversikt (refereegranskat)abstract
- The individual of a species is the basic unit which responds to climate and UV-B changes, and it responds over a wide range of time scales. The diversity of animal, plant and microbial species appears to be low in the Arctic, and decreases from the boreal forests to the polar deserts of the extreme North but primitive species are particularly abundant. This latitudinal decline is associated with an increase in super-dominant species that occupy a wide range of habitats. Climate warming is expected to reduce the abundance and restrict the ranges of such species and to affect species at their northern range boundaries more than in the South: some Arctic animal and plant specialists could face extinction. Species most likely to expand into tundra are boreal species that currently exist as outlier populations in the Arctic. Many plant species have characteristics that allow them to survive short snow-free growing seasons, low solar angles, permafrost and low soil temperatures, low nutrient availability and physical disturbance. Many of these characteristics are likely to limit species responses to climate warming, but mainly because of poor competitive ability compared with potential immigrant species. Terrestrial Arctic animals possess many adaptations that enable them to persist under a wide range of temperatures in the Arctic. Many escape unfavorable weather and resource shortage by winter dormancy or by migration. The biotic environment of Arctic animal species is relatively simple with few enemies, competitors, diseases, parasites and available food resources. Terrestrial Arctic animals are likely to be most vulnerable to warmer and drier summers, climatic changes that interfere with migration routes and staging areas, altered snow conditions and freeze-thaw cycles in winter, climate-induced disruption of the seasonal timing of reproduction and development, and influx of new competitors, predators, parasites and diseases. Arctic microorganisms are also well adapted to the Arctics climate: some can metabolize at temperatures down to -39degreesC. Cyanobacteria and algae have a wide range of adaptive strategies that allow them to avoid, or at least minimize UV injury. Microorganisms can tolerate most environmental conditions and they have short generation times which can facilitate rapid adaptation to new environments. In contrast, Arctic plant and animal species are very likely to change their distributions rather than evolve significantly in response to warming.
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| 4. |
- Callaghan, T. V., et al.
(författare)
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Effects on the function of arctic ecosystems in the short- and long-term perspectives
- 2004
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Ingår i: Ambio: a Journal of Human Environment. - : Royal Swedish Academy of Sciences. - 0044-7447. ; 33, s. 448-458
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Tidskriftsartikel (refereegranskat)abstract
- Abstract in UndeterminedHistorically, the function of Arctic ecosystems in terms of cycles of nutrients and carbon has led to low levels of primary production and exchanges of energy, water and greenhouse gases have led to low local and regional cooling. Sequestration of carbon from atmospheric CO2, in extensive, cold organic soils and the high albedo from low, snow-covered vegetation have had impacts on regional climate. However, many aspects of the functioning of Arctic ecosystems are sensitive to changes in climate and its impacts on biodiversity. The current Arctic climate results in slow rates of organic matter decomposition. Arctic ecosystems therefore tend to accumulate organic matter and elements despite low inputs. As a result, soil-available elements like nitrogen and phosphorus are key limitations to increases in carbon fixation and further biomass and organic matter accumulation. Climate warming is expected to increase carbon and element turnover, particularly in soils, which may lead to initial losses of elements but eventual, slow recovery. Individual species and species diversity have clear impacts on element inputs and retention in Arctic ecosystems. Effects of increased CO2 and UV-B on whole ecosystems, on the other hand, are likely to be small although effects on plant tissue chemisty, decomposition and nitrogen fixation may become important in the long-term. Cycling of carbon in trace gas form is mainly as CO2 and CH4. Most carbon loss is in the form of CO2, produced by both plants and soil biota. Carbon emissions as methane from wet and moist tundra ecosystems are about 5% of emissions as CO2 and are responsive to warming in the absence of any other changes. Winter processes and vegetation type also affect CH4 emissions as well as exchanges of energy between biosphere and atmosphere. Arctic ecosystems exhibit the largest seasonal changes in energy exchange of any terrestrial ecosystem because of the large changes in albedo from late winter, when snow reflects most incoming radiation, to summer when the ecosystem absorbs most incoming radiation. Vegetation profoundly influences the water and energy exchange of Arctic ecosystems. Albedo during the period of snow cover declines from tundra to forest tundra to deciduous forest to evergreen forest. Shrubs and trees increase snow depth which in turn increases winter soil temperatures. Future changes in vegetation driven by climate change are therefore, very likely to profoundly alter regional climate.
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| 5. |
- Callaghan, Terry V., et al.
(författare)
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Effects on the structure of arctic ecosystems in the short- and long-term perspectives
- 2004
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Ingår i: Ambio: a Journal of Human Environment. - : Royal Swedish Academy of Sciences. - 0044-7447. ; 33:7, s. 436-447
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Forskningsöversikt (refereegranskat)abstract
- Species individualistic responses to warming and increased UV-B radiation are moderated by the responses of neighbors within communities, and trophic interactions within ecosystems. All of these responses lead to changes in ecosystem structure. Experimental manipulation of environmental factors expected to change at high latitudes showed that summer warming of tundra vegetation has generally led to smaller changes than fertilizer addition. Some of the factors manipulated have strong effects on the structure of Arctic ecosystems but the effects vary regionally, with the greatest response of plant and invertebrate communities being observed at the coldest locations. Arctic invertebrate communities are very likely to respond rapidly to warming whereas microbial biomass and nutrient stocks are more stable. Experimentally enhanced UV-B radiation altered the community composition of gram-negative bacteria and fungi, but not that of plants. Increased plant productivity due to warmer summers may dominate food-web dynamics. Trophic interactions of tundra and sub-Arctic forest plant-based food webs are centered on a few dominant animal species which often have cyclic population fluctuations that lead to extremely high peak abundances in some years. Population cycles of small rodents and insect defoliators such as the autumn moth affect the structure and diversity of tundra and forest-tundra vegetation and the viability of a number of specialist predators and parasites. Ice crusting in warmer winters is likely to reduce the accessibility of plant food to lemmings, while deep snow may protect them from snow-surface predators. In Fennoscandia, there is evidence already for a pronounced shift in small rodent community structure and dynamics that have resulted in a decline of predators that specialize in feeding on small rodents. Climate is also likely to alter the role of insect pests in the birch forest system: warmer winters may increase survival of eggs and expand the range of the insects. Insects that harass reindeer in the summer are also likely to become more widespread, abundant and active during warmer summers while refuges for reindeer/caribou on glaciers and late snow patches will probably disappear.
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| 6. |
- Callaghan, Terry V., et al.
(författare)
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Responses to projected changes in climate and UV-B at the species level
- 2004
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Ingår i: Ambio: a Journal of Human Environment. - : Royal Swedish Academy of Sciences. - 0044-7447. ; 33:7, s. 418-435
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Forskningsöversikt (refereegranskat)abstract
- Environmental manipulation experiments showed that species respond individualistically to each environmental-change variable. The greatest responses of plants were generally to nutrient, particularly nitrogen, addition. Summer warming experiments showed that woody plant responses were dominant and that mosses and lichens became less abundant. Responses to warming were controlled by moisture availability and snow cover. Many invertebrates increased population growth in response to summer warming, as long as desiccation was not induced. CO2 and UV-B enrichment experiments showed that plant and animal responses were small. However, some microorganisms and species of fungi were sensitive to increased UV-B and some intensive mutagenic actions could, perhaps, lead to unexpected epidemic outbreaks. Tundra soil heating, CO 2 enrichment and amendment with mineral nutrients generally accelerated microbial activity. Algae are likely to dominate cyanobacteria in milder climates. Expected increases in winter freeze-thaw cycles leading to ice-crust formation are likely to severely reduce winter survival rate and disrupt the population dynamics of many terrestrial animals. A deeper snow cover is likely to restrict access to winter pastures by reindeer/caribou and their ability to flee from predators while any earlier onset of the snow-free period is likely to stimulate increased plant growth. Initial species responses to climate change might occur at the sub-species level: an Arctic plant or animal species with high genetic/racial diversity has proved an ability to adapt to different environmental conditions in the past and is likely to do so also in the future. Indigenous knowledge, air photographs, satellite images and monitoring show that changes in the distributions of some species are already occurring: Arctic vegetation is becoming more shrubby and more productive, there have been recent changes in the ranges of caribou, and "new" species of insects and birds previously associated with areas south of the treeline have been recorded. In contrast, almost all Arctic breeding bird species are declining and models predict further quite dramatic reductions of the populations of tundra birds due to warming. Species-climate response surface models predict potential future ranges of current Arctic species that are often markedly reduced and displaced northwards in response to warming. In contrast, invertebrates and microorganisms are very likely to quickly expand their ranges northwards into the Arctic.
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| 7. |
- Callaghan, Terry V., et al.
(författare)
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Synthesis of effects in four Arctic subregions
- 2004
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Ingår i: Ambio: a Journal of Human Environment. - : Royal Swedish Academy of Sciences. - 0044-7447. ; 33:7, s. 469-473
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Tidskriftsartikel (refereegranskat)abstract
- An assessment of impacts on Arctic terrestrial ecosystems has emphasized geographical variability in responses of species and ecosystems to environmental change. This variability is usually associated with north-south gradients in climate, biodiversity, vegetation zones, and ecosystem structure and function. It is clear, however, that significant east-west variability in environment, ecosystem structure and function, environmental history, and recent climate variability is also important. Some areas have cooled while others have become warmer. Also, east-west differences between geographical barriers of oceans, archipelagos and mountains have contributed significantly in the past to the ability of species and vegetation zones to relocate in response to climate changes, and they have created the isolation necessary for genetic differentiation of populations and biodiversity hot-spots to occur. These barriers will also affect the ability of species to relocate during projected future warming. To include this east-west variability and also to strike a balance between overgeneralization and overspecialization, the ACIA identified four major sub regions based on large-scale differences in weather and climate-shaping factors. Drawing on information, mostly model output that can be related to the four ACIA subregions, it is evident that geographical barriers to species re-location, particularly the distribution of landmasses and separation by seas, will affect the northwards shift in vegetation zones. The geographical constraints-or facilitation-of northward movement of vegetation zones will affect the future storage and release of carbon, and the exchange of energy and water between biosphere and atmosphere. In addition, differences in the ability of vegetation zones to re-locate will affect the biodiversity associated with each zone while the number of species threatened by climate change varies greatly between subregions with a significant hot-spot in Beringia. Overall, the subregional synthesis demonstrates the difficulty of generalizing projections of responses of ecosystem structure and function species loss, and biospheric feedbacks to the climate system for the whole Arctic region and implies a need for a far greater understanding of the spatial variability in the responses of terrestrial arctic ecosystems to climate change.
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| 8. |
- Callaghan, Terry V., et al.
(författare)
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Uncertainties and recommendations
- 2004
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Ingår i: Ambio: a Journal of Human Environment. - : Royal Swedish Academy of Sciences. - 0044-7447. ; 33:7, s. 474-479
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Tidskriftsartikel (refereegranskat)abstract
- An assessment of the impacts of changes in climate and UV-B radiation on Arctic terrestrial ecosystems, made within the Arctic Climate Impacts Assessment (ACIA), highlighted the profound implications of projected warming in particular for future ecosystem services, biodiversity and feedbacks to climate. However, although our current understanding of ecological processes and changes driven by climate and UV-B is strong in some geographical areas and in some disciplines, it is weak in others. Even though recently the strength of our predictions has increased dramatically with increased research effort in the Arctic and the introduction of new technologies, our current understanding is still constrained by various uncertainties. The assessment is based on a range of approaches that each have uncertainties, and on data sets that are often far from complete. Uncertainties arise from methodologies and conceptual frameworks, from unpredictable surprises, from lack of validation of models, and from the use of particular scenarios, rather than predictions, of future greenhouse gas emissions and climates. Recommendations to reduce the uncertainties are wide-ranging and relate to all disciplines within the assessment. However, a repeated theme is the critical importance of achieving an adequate spatial and long-term coverage of experiments, observations and monitoring of environmental changes and their impacts throughout the sparsely populated and remote region that is the Arctic.
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| 9. |
- Moraes, Rosana, 1968, et al.
(författare)
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Pesticide residues in rivers of a Brazilian Rain Forest Reserve: Assessing the potential concern for effects on aquatic life and human health.
- 2003
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Ingår i: Ambio. - : Royal Swedish Academy of Sciences. - 0044-7447 .- 1654-7209. ; 32:4, s. 258-263
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Tidskriftsartikel (refereegranskat)abstract
- Pesticide residues in water, sediment, and fish samples from rivers of a Brazilian Rain Forest Reserve were measured in November 1998, March 1999, and January 2000. Concentrations of the individual pesticides were compared to ecotoxicological benchmarks based on acute toxicity tests, and to regulatory guidelines to determine the potential concern for effects on aquatic life and human health. Pesticides and metabolites were detected at all 7 sites surveyed. Residues of a total of 27 pesticides or metabolites were found in water and/or sediment samples and fish have accumulated some of the most persistent of these residues. Measured concentrations in water and sediment indicated concern for preservation of aquatic fauna. Several pesticides in water were above levels for drinking water recommended by Brazilian and/or European Union authorities, indicating also a concern for human health.
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| 10. |
- Olsson, Lennart, et al.
(författare)
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Soil carbon sequestration in degraded semiarid agro-ecosystems - Perils and Potentials
- 2002
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Ingår i: Ambio: a Journal of Human Environment. - : Royal Swedish Academy of Sciences. - 0044-7447. ; 31:6, s. 471-477
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Tidskriftsartikel (refereegranskat)abstract
- The Kyoto Protocol opens new possibilities for using the biosphere as a carbon sink. Using agro-ecosystems as carbon sinks may be the most appropriate practice from both environmental and socioeconomic points of view. Degraded agro-ecosystems in Africa might benefit significantly from the improved land management that would be part of a carbon sequestration program. There are vast areas of these agro-ecosystems in Africa and their rehabilitation is an urgent matter. We agree with UNEP that there are potentially important synergies to be made between the Convention on Climate Change, the UN Convention to Combat Desertification and the UN Convention on Biodiversity. In this paper, we have investigated the potential for increasing soil carbon content in semiarid agro-ecosystems in the Sudan and found that increasing fallow periods will result in increased soil carbon content and converting marginal agricultural areas to rangeland will restore the carbon levels to 80% of the natural savannah carbon levels in 100 years. The economic gain from a future carbon sequestration program has the potential of a significant contribution to the household economy in these agro-ecosystems.
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| 11. |
- Rosborg, Ingegerd, et al.
(författare)
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Hair element concentrations in females in one acid and one alkaline area in southern Sweden.
- 2003
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Ingår i: Ambio: a Journal of Human Environment. - : Royal Swedish Academy of Sciences. - 0044-7447. ; 32:7, s. 440-446
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Tidskriftsartikel (refereegranskat)abstract
- Concentrations of 34 trace elements in hair have been determined in 47 females from an acid region in southern Sweden, who were compared with 43 females from an alkaline area. The concentrations of these elements in hair and drinking water were determined by inductively coupled plasma optical emission spectroscopy and inductively coupled plasma mass spectrometry. The hair concentrations of boron and barium were significantly higher (p < 0.001) in hair samples from the acid region, the hair levels of calcium, strontium, molybdenum, iron, and selenium were significantly higher (p < 0.001), in the alkaline region. For some metals, e.g. calcium, lead, molybdenum, and strontium, there were positive correlations between the concentrations in hair and water (r(s) = 0.34-0.57; p less than or equal to 0.001), indicating the importance of intake from minerals in water. The increased ratio of selenium/mercury concentrations in hair samples obtained in the alkaline district (p < 0.001) indicates that these subjects may have better protection against the toxic effects of mercury.
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| 12. |
- Urbel, Evelin, et al.
(författare)
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Exploring the Sustainability of Estonian Forestry: The Socioeconomic Drivers
- 2009
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Ingår i: Ambio: a Journal of Human Environment. - : Royal Swedish Academy of Sciences. - 0044-7447. ; 38:2, s. 101-108
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Tidskriftsartikel (refereegranskat)abstract
- Forestry as an important industry has both direct as well as indirect effects on the Estonian economy. It is therefore essential that it is sustainably managed so that it can continue to contribute to the economy in the future. The first aim of this article is to establish the situation regarding felling and regeneration in Estonia. As the available forestry statistics display discrepancies and lack consistency, it was as a necessary first step to gather information about and analyze the validity and reliability of the prime data to make the data sets useful for comparison over time and establish the current trends in Estonian forestry. However, with the help of interviews we are able to show that economic instability in Estonia brings with it increased logging rates and hinders investments into regeneration and maintenance. The problems are particularly pronounced in private forestry. Second, the article seeks to explain the socioeconomic reasons behind this situation. Economic problems among private owners, a liberal forestry policy, together with rapid land reform and weak enforcement of forestry legislation are some of the reasons that can explain the forestry trends in Estonia.
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| 13. |
- Wiktelius, S, et al.
(författare)
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Desert locust control in ecologically sensitive areas: Need for guidelines.
- 2003
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Ingår i: Ambio: a Journal of Human Environment. - : Royal Swedish Academy of Sciences. - 0044-7447. ; 32:7, s. 463-468
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Tidskriftsartikel (refereegranskat)abstract
- Chemical control of desert locust (DL) is carried out over large areas of land, covering a range of different landscapes and ecosystems. There are no real restrictions for spraying in or close to environmentally sensitive areas and awareness of sensitivity is not always obvious to the people involved in control. However, concern about environmental issues in connection with DL control is growing and clear guidelines are needed. The objectives were: to identify and delineate areas particularly sensitive to pesticide contamination in northeastern Africa, e.g. protected areas, wetlands, populated places, oases, and areas with concentrations of migratory birds. These areas were matched with actual DL control during 1986-1998. The conclusion is that chemical control occurred in environmentally sensitive areas especially wetlands, e.g. temporary waters and mangroves; close to human settlements; and, to some extent, in or near protected areas and areas with numerous migratory birds.
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| 14. |
- Bishop, Kevin, et al.
(författare)
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Nature as the "Natural" Goal for Water Management : A Conversation
- 2009
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Ingår i: Ambio. - : Springer Netherlands. - 0044-7447 .- 1654-7209. ; Volume 38:Issue 4
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- The goals for water-quality and ecosystem integrity are often defined relative to "natural" reference conditions in many water-management systems, including the European Union Water Framework Directive. This paper examines the difficulties created for water management by using "natural" as the goal. These difficulties are articulated from different perspectives in an informal (fictional) conversation that takes place after a workshop on reference conditions in water-resources management. The difficulties include defining the natural state and modeling how a system might be progressed toward the natural, as well as the feasibility and desirability of restoring a natural state. The paper also considers the appropriateness for developing countries to adopt the use of natural as the goal for water management. We conclude that failure to critically examine the complexities of having "natural" as the goal will compromise the ability to manage the issues that arise in real basins by not making the ambiguities associated with this "natural" goal explicit. This is unfortunate both for the western world that has embraced this model of "natural as the goal" and for the developing world in so far as they are encouraged to adopt this model.
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| 15. |
- Alkan Olsson, Johanna, et al.
(författare)
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Local stakeholders acceptance of model-generated data used as a communication tool in water management: The Ronnea study
- 2005
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Ingår i: Ambio. - : Royal Swedish Academy of Sciences. - 0044-7447 .- 1654-7209. ; 34:7, s. 507-512
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Tidskriftsartikel (refereegranskat)abstract
- The objective of this study was to increase the knowledge of local stakeholders acceptance of model-generated data when used as a communication tool in water quality management. The Ronnea catchment in the southwest of Sweden was chosen as the study area. The results indicate the model-generated data served as a uniting factor. Simultaneously, the stakeholders were concerned with presented data, the main problems being sources of pollution, which were not accounted for, lack of trustworthiness when measuring pollution, and the uncertainty of the impact of natural variation and delayed effects. Four clusters of factors were identified as influencing stakeholders acceptance of the model-generated data: confidence in its practical applications, confidence in the people involved in or providing material for the dialog (such as experts, decision-makers, and media), the social characteristics of the participants (such as age and profession), and the way of communicating the data (such as tone of communication, group composition, duration, and geographical scope of the dialog). The perception of the fairness of the practical application of given model-generated data was also an important factor for acceptance.
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| 16. |
- Angelstam, Per, 1953-, et al.
(författare)
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Two-dimensional gap analysis : a tool for efficient conservation planning and biodiversity policy implementation
- 2003
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Ingår i: Ambio. - : Royal Swedish Academy of Sciences. - 0044-7447 .- 1654-7209. ; 32:8, s. 527-534
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Tidskriftsartikel (refereegranskat)abstract
- The maintenance of biodiversity by securing representative and well-connected habitat networks in managed landscapes requires a wise combination of protection, management, and restoration of habitats at several scales. We suggest that the integration of natural and social sciences in the form of "Two-dimensional gap analysis" is an efficient tool for the implementation of biodiversity policies. The tool links biologically relevant "horizontal" ecological issues with "vertical" issues related to institutions and other societal issues. Using forest biodiversity as an example, we illustrate how one can combine ecological and institutional aspects of biodiversity conservation, thus facilitating environmentally sustainable regional development. In particular, we use regional gap analysis for identification of focal forest types, habitat modelling for ascertaining the functional connectivity of "green infrastructures", as tools for the horizontal gap analysis. For the vertical dimension we suggest how the social sciences can be used for assessing the success in the implementation of biodiversity policies in real landscapes by identifying institutional obstacles while implementing policies. We argue that this interdisciplinary approach could be applied in a whole range of other environments including other terrestrial biota and aquatic ecosystems where functional habitat connectivity, nonlinear response to habitat loss and a multitude of economic and social interests co-occur in the same landscape.
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| 17. |
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| 18. |
- Bishop, Kevin, et al.
(författare)
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The Effects of Forestry on Hg Bioaccumulation in Nemoral/Boreal Waters and Recommendations for Good Silvicultural Practice
- 2009
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Ingår i: Ambio. - : Royal Swedish Academy of Sciences. - 0044-7447 .- 1654-7209. ; 38:7, s. 373-380
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Tidskriftsartikel (refereegranskat)abstract
- Mercury (Hg) levels are alarmingly high in fish from lakes across Fennoscandia and northern North America. The few published studies on the ways in which silviculture practices influence this problem indicate that forest operations increase Hg in downstream aquatic ecosystems. From these studies, we estimate that between one-tenth and one-quarter of the Hg in the fish of high-latitude, managed forest landscapes can be attributed to harvesting. Forestry, however, did not create the elevated Hg levels in the soils, and waterborne Hg/MeHg concentrations downstream from harvested areas are similar to those from wetlands. Given the current understanding of the way in which silviculture impacts Hg cycling, most of the recommendations for good forest practice in Sweden appear to be appropriate for high-latitude regions, e.g., leaving riparian buffer zones, as well as reducing disturbance at stream crossings and in moist areas. The recommendation to restore wetlands and reduce drainage, however, will likely increase Hg/MeHg loadings to aquatic ecosystems
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| 19. |
- Carlsson, Lars, et al.
(författare)
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Institutional frameworks for sustainability? : a comparative analysis of the forest sectors of Russia and the Baltic States
- 2004
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Ingår i: Ambio. - : Royal Swedish Academy of Sciences. - 0044-7447 .- 1654-7209. ; 33:6, s. 366-370
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Tidskriftsartikel (refereegranskat)abstract
- After the break-up of the Soviet system, the divergence in forest management among Soviet republics became obvious. While the forest sectors of the Baltic States have been fundamentally changed, Russia has not been able to develop an institutional framework that would fit the prerequisites for social-ecological resilience. It is argued that sustainable development requires institutional frameworks that have the capacity to adapt and learn, and thus to treat policies as experiments that are constantly assessed and readjusted. This, however, requires a participatory approach and in this respect the Baltic States are believed to be on a more promising track. Finally, it is concluded that only to the extent that suitable institutional frameworks will be developed will social-ecological resilience be a significant feature of the natural resources management in the former communist countries.
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| 20. |
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| 21. |
- Gren, Ing-Marie, et al.
(författare)
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Costs of alien invasive species in Sweden
- 2009
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Ingår i: Ambio. - : Springer Netherlands. - 0044-7447 .- 1654-7209. ; 38:3
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Tidskriftsartikel (refereegranskat)abstract
- The purpose of this paper is to present calculations of total costs of 13 alien invasive species (AIS) in Sweden. All species are subject to control by Swedish public authorities, and estimates for most AIS include either damage cost or actual control cost. The results indicate a total annual cost between approximately 1620 and 5080 million SEK, which correspond to SEK 175 and SEK 565 per capita in Sweden. The estimates are well within the range of similar calculations for other countries, but differ with respect to the composition of costs of different AIS. Whereas costs for the agricultural and forestry sectors dominate in most other studies, the costs of AIS in Sweden are more equally divided among different categories. The results also indicate that the highest costs are attributable to unintentionally introduced AIS and that the most reliable cost estimates are related to human and animal health.
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| 22. |
- Gröndahl, Fredrik
(författare)
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Removal of Surface Blooms of the Cyanobacteria Nodularia spumigena : A Pilot Project Conducted in the Baltic Sea
- 2009
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Ingår i: Ambio. - : Royal Swedish Academy of Sciences. - 0044-7447 .- 1654-7209. ; 38:2, s. 79-84
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Tidskriftsartikel (refereegranskat)abstract
- Blooms of Cyanobacteria are a major concern during the summer period in the Baltic Sea Proper. The nitrogen-fixing Nodularia spumigena forms massive toxic blooms in the surface layers, with a concentration of biomass in the uppermost 1-m water layer. This pilot study describes the construction and test of a Nodularia collecting device during the summer of 2006. Oil booms were modified so that their dragging skirt was replaced with a water-permeable forming fabric used in the pulp and paper industry. The results showed that the modified oil booms worked and operated in an effective way when towed in the sea. Calculations showed that the collecting device used in this study has a theoretical capacity of cleaning 0.055 km(2) (5.5 ha) of sea surface hr(-1), compared with the 6600 km(2) of the Baltic Sea that were covered by Nodularia blooms during the summer of 2005. Future possibilities for Nodularia harvesting are discussed.
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| 23. |
- Jonsson, Anna
(författare)
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Public participation in water resources management: Stakeholder voices on degree, scale, potential, and methods in future water management
- 2005
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Ingår i: Ambio. - : Springer Verlag (Germany). - 0044-7447 .- 1654-7209. ; 34:7, s. 495-500
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Tidskriftsartikel (refereegranskat)abstract
- The European Water Framework Directive puts strong emphasis on stakeholder and public participation in water management. Several practical questions regarding who should be involved, why, when, and how still remain unanswered. This paper investigates stakeholders' own experiences and views of increased public participation in water management. The article also explores the potential for increasing levels of participation by forming catchment committees with representation from stakeholder groups and through the use of various practical methods for participation. For both these aspects of participation, the views, expectations, and apprehensions of different stakeholder groups involved in nutrient loss management are investigated. Stakeholder opinions were collected by inviting representatives from five stakeholder groups within the Rönneå catchment in southern Sweden to a catchment dialog process.
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| 24. |
- Juhna, Talis, et al.
(författare)
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Water-Quality Changes in Latvia and Riga 1980–2000: Possibilities and Problems
- 2001
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Ingår i: Ambio. - : Royal Swedish Academy of Sciences. - 0044-7447 .- 1654-7209. ; 30:4-5, s. 306-14
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Tidskriftsartikel (refereegranskat)abstract
- Long-term changes in the environmental quality of water in Latvia (chemical composition of inland waters, wastewater treatment, and drinking-water treatment practices and quality) as a response to socioeconomic changes have been studied. Water composition, the major factors influencing water chemistry, and human impacts (wastewater loading) were studied to determine changes that occurred after recent reductions in pollution emissions, particularly nutrient loading, to surface waters. After 1991, (Latvia regained independence in 1991) inland water quality has begun to improve mainly as a result of decreases in nutrient loads from point and nonpoint sources and substantial efforts in the area of environmental protection. The situation differs, however, for drinking-water treatment, where practices have also changed during the whole period from 1980 till 2000. More stringent drinking-water-quality standards and novel insights regarding changes in water quality in the distribution network, necessitate further improvements in public water supply, and place this particular water issue among Latvia's main priorities.
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| 25. |
- Karlsson, Per Erik, 1957, et al.
(författare)
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Evidence for Impacts of Near-ambient Ozone Concentrations on Vegetation in Southern Sweden
- 2009
-
Ingår i: Ambio. - : Royal Swedish Academy of Sciences. ; 38:8, s. 425-431
-
Tidskriftsartikel (refereegranskat)abstract
- Substantial impacts of near-ambient ozone concentrations on agricultural crops, trees, and seminatural vegetation are demonstrated for southern Sweden. Impacts of ambient ozone levels (2–15 μL L-¹ hr annual accumulated ozone exposure over a threshold of 40 nL L-¹ [AOT40]) range from a 2%–10% reduction for trees (e.g., leaf chlorophyll, tree growth) up to a 15% reduction for crops (e.g., yield, wheat/potato). Visible leaf injury on bioindicator plants caused by ambient ozone levels has been clearly demonstrated. The humid climatic conditions in Sweden promote high rates of leaf ozone uptake at a certain ozone concentration. This likely explains the comparatively large ozone impacts found for vegetation in southern Sweden at relatively low ozone concentrations in the air. It is important that the future methods used for the representation of ozone impacts on vegetation across Europe are based on the leaf ozone uptake concept and not on concentration-based exposure indices, such as AOT40.
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| 26. |
- Karlsson, Per Erik, 1957, et al.
(författare)
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Ozone Exposure and Impacts on Vegetation in the Nordic and Baltic Countries
- 2009
-
Ingår i: Ambio. - : Royal Swedish Academy of Sciences. - 0044-7447 .- 1654-7209. ; 38:8, s. 402-405
-
Tidskriftsartikel (refereegranskat)abstract
- Ozone concentrations are generally considerably lower over northern Europe as compared with continental and southern Europe. However, ozone becomes toxic for vegetation mainly after it has been taken up into the leaf interior through the stomata. The rates of ozone uptake into the leaves are, somewhat simplified, the product of the air ozone concentrations and the degree of stomatal opening. The phytotoxic impacts of ozone can be almost as important in northern Europe as they are in continental and southern Europe. The long daylight hours as well as the rather humid environment conditions, both in the air and soil, promote stomatal openings in northern Europe. This article summarizes scientific evidence that supports the conclusion that ozone abatement policies regarding vegetation in Europe, as well as in the rest of the world, should be based on estimates of the leaf ozone uptake and not only on the ozone concentration in the air.
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| 27. |
- Köhlin, Gunnar, et al.
(författare)
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Impact of Plantations on Forest Use and Forest Status in Orissa, India
- 2001
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Ingår i: Ambio. - : Royal Swedish Academy of Sciences. - 0044-7447 .- 1654-7209. ; 30:1, s. 37-42
-
Tidskriftsartikel (refereegranskat)abstract
- In Orissa 100 thousand ha of village plantations were established from 1985 to 1992 as an aid project to support the subsistence needs of rural poor and to relieve heavy pressure on the natural forests. The aim of this paper is to examine the welfare and environmental effects of these village plantations. To do this, extensive data collection was needed which included both household utilization of different sources of biomass as well as remote-sensing information, to establish the status of the vegetation and it's spatial location vis-a-vis the users. The study shows that plantations have the potential for substantial welfare improvements for the target population, especially women, through increased consumption of biomass, decreased time for collection and decreased pressure on natural forests. However, interventions need to be very selective in order to be successful, with special consideration given to plantation location compared to natural forest.
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| 28. |
- Laudon, Hjalmar, et al.
(författare)
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Response of Dissolved Organic Carbon following Forest Harvesting in a Boreal Forest
- 2009
-
Ingår i: AMBIO: A Journal of the Human Environment. - : Royal Swedish Academy of Sciences. - 0044-7447 .- 1654-7209. ; 38, s. 381-386
-
Tidskriftsartikel (refereegranskat)abstract
- To determine if forestry affects stream water dissolved organic carbon (DOC) concentrations, we conducted high frequency water sampling at a clear-cut catchment experiment in northern Sweden 1 year after harvesting. The overall finding was that harvesting significantly increased stream water DOC in these boreal forest catchments, at least during the growing season. The results indicate a DOC concentration increase of up to 50% during early summer on the two harvested catchments relative to the two control catchments. The analysis supports the hypothesis that a raised groundwater level following harvesting caused the increased DOC concentration during both hydrological episodes and low flow conditions. Harvesting resulted in a 70% increase in DOC export due to the combined effect of runoff and DOC concentration during the June-October study period. Given the extent of forestry activity in the boreal landscape, these results demonstrate that tree harvesting will affect the water quality of the region.
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| 29. |
- Lindahl, Odd, et al.
(författare)
-
Improving marine water quality by mussel farming: A profitable solution for Swedish society
- 2005
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Ingår i: Ambio. - : Allen Press Inc.. - 0044-7447 .- 1654-7209. ; 34:2, s. 131-138
-
Tidskriftsartikel (refereegranskat)abstract
- Eutrophication of coastal waters is a serious environmental problem with high costs for society globally. In eastern Skagerrak, reductions in eutrophication are planned through reduction of nitrogen inputs, but it is unclear how this can be achieved. One possible method is the cultivation of filter-feeding organisms, such as blue mussels, which remove nitrogen while generating seafood, fodder and agricultural fertilizer, thus recycling nutrients from sea to land. The expected effect of mussel farming on nitrogen cycling was modeled for the Gullmar Fjord on the Swedish west coast and it is shown that the net transport of nitrogen (sum of dissolved and particulate) at the fjord mouth was reduced by 20%. Existing commercial mussel farms already perform this service for free, but the benefits to society could be far greater. We suggest that rather than paying mussel farmers for their work that nutrient trading systems are introduced to improve coastal waters. In this context an alternative to nitrogen reduction in the sewage treatment plant in Lysekil community through mussel farming is presented. Accumulation of bio-toxins has been identified as the largest impediment to further expansion of commercial mussel farming in Sweden, but the problem seems to be manageable through new techniques and management strategies. On the basis of existing and potential regulations and payments, possible win-win solutions are suggested.
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| 30. |
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| 31. |
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| 32. |
- Marques, Marcia, et al.
(författare)
-
Water environments : Anthropogenic pressures and ecosystem changes in the Atlantic drainage basins of Brazil
- 2004
-
Ingår i: Ambio. - : Royal Swedish Academy of Sciences. - 0044-7447 .- 1654-7209. ; 33:1-2, s. 68-77
-
Tidskriftsartikel (refereegranskat)abstract
- Densely occupied drainage basins and coastal zones in developing countries that are facing economic growth are likely to suffer from moderate to severe environmental impacts regarding different issues. The catchment basins draining towards the Atlantic coast from northeastern to southern Brazil include a wide range of climatic zones and diverse ecosystems. Within its borders lies the Atlantic rain forest, significant extensions of semiarid thorn forests (caatinga), vast tree and scrub woodlands (cerrado) and most of the 6670 km of the Brazilian coast and its marine ecosystems. In recent decades, human activities have increasingly advanced over these natural resources. Littoralization has imposed a burden on coastal habitats and communities. Most of the native vegetation of the cerrado and caatinga was removed and only 7% of the original Atlantic rainforest still exists. Estuaries, bays and coastal lagoons have been irreversibly damaged. Land uses, damming and water diversion have become the major driving forces for habitat loss and aquatic ecosystem modification. Regardless of the contrast between the drought-affected northeastern Brazil and the much more prosperous and industrialized southeastern/southern Brazil, the impacts on habitat and communities were found equally severe in both cases. Attempts to halt environmental degradation have not been effective. Instead of focusing on natural resources separately, it is suggested that more integrated environmental policies that focus on aquatic ecosystems integrity are introduced.
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| 33. |
- Nyqvist, Anna, 1961, et al.
(författare)
-
Dynamics of Seagrass Meadows on the Swedish Skagerrak Coast
- 2009
-
Ingår i: Ambio. - : Royal Swedish Academy of Sciences. - 0044-7447 .- 1654-7209. ; 38:2, s. 85-88
-
Tidskriftsartikel (refereegranskat)abstract
- Seagrasses have declined in many places around the world, and the Swedish Skagerrak coast is no exception. Between the 1980s and 2000, the cover of eelgrass (Zostera marina L.) on the Swedish Skagerrak coast decreased about 60%. In the present study, the sites that were investigated in the 1980s and 2000 were revisited (1655 ha) in 2003 and 2004 to investigate long and short term temporal and spatial differences in eelgrass coverage. The distribution of eelgrass was mapped from a small boat using an aquascope and a GPS receiver. No variation in total (about 150 km) or regional (about 20 km) eelgrass cover was found between 2000 and 2004, but there were substantial changes (both losses and gains) in meadow size on a local (less than about 2 km) scale. The results have implications for management of shallow soft bottoms, particularly because it was shown that even though no eelgrass is found in a single survey in a specific area, there could be eelgrass growing there in the following years.
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| 34. |
- Rehnstam-Holm, Ann-Sofi, 1959, et al.
(författare)
-
Shellfish and public health: A Swedish perspective
- 2005
-
Ingår i: Ambio. - : Allen Press Inc.. - 0044-7447 .- 1654-7209. ; 34:2, s. 139-144
-
Tidskriftsartikel (refereegranskat)abstract
- Bivalves are ancient animals that feed by filtering large volumes of water. In this way, phytoplankton, bacteria and viruses from the water column are greatly concentrated in the mussels. The hazards associated with the consumption of mussels are thus dependent on the occurrence and composition of toxic algae and human microbial pathogens in the areas where shellfish are grown. Diarrheic shellfish m toxins have occurred regularly in Sweden during the past 27 years. Peaks of toxins in mussels are mostly recorded from October to December, but the pattern can differ significantly due to location and year, making it hard to predict toxin levels in mussels. With an expansion of aquaculture and a subsequent increase in seafood consumption, better risk management is needed to minimize the effects on humans of algal toxins and human pathogens. New control strategies that have to be implemented are: i) proper site selection of culture installations; ii) regular and cost-efficient monitoring of algae, bacteria and viruses; iii) new indicators for fecal contamination, suitable for the specific locations where shellfish grow; iv) rapid dissemination of information to the industry and public, including risk assessment and advice on how to cope with the situation.
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| 35. |
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| 36. |
- Sörensen, Rasmus, et al.
(författare)
-
Forest Harvest Increases Runoff Most during Low Flows in Two Boreal Streams
- 2009
-
Ingår i: Ambio. - : Royal Swedish Academy of Sciences. - 0044-7447 .- 1654-7209. ; 38:7, s. 357-363
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- To understand how forest harvest influences the aquatic environment, it is essential to determine the changes in the flow regime. This paper presents changes in the hydrological regime during the first 2 y after harvest in two catchments of the Balsjo Catchment Study in Sweden. The changes were judged relative to a reference catchment, calibrated during an 18-mo pretreatment period starting in September 2004. From August 2006 through March 2008, there was an average of 35% more runoff from the harvested catchments relative to the reference. The flow increased most during the growing seasons and at base flows (< 1 mm d(-1); 58-99% increase), followed by dormant season and intermediate flows (30-43%). No significant changes were observed during the highest flows (over 5 mm d(-1)), except for the spring flood a few weeks after harvest, which was delayed and attenuated. Large relative changes in low flow may influence the ecosystem by altering the aquatic habitat
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| 37. |
- Sörensen, Rasmus, et al.
(författare)
-
The Effects of Forest Harvest Operations on Mercury and Methylmercury in Two Boreal Streams : Relatively Small Changes in the First Two Years prior to Site Preparation
- 2009
-
Ingår i: Ambio. - : Royal Swedish Academy of Sciences. - 0044-7447 .- 1654-7209. ; 38:7, s. 364-372
-
Tidskriftsartikel (refereegranskat)abstract
- Forest harvest is hypothesized to increase the mercury (Hg) load in aquatic ecosystems. The Balsjo paired catchment study examined the outputs of methylmercury (MeHg) and total mercury (Hg-tot) from two boreal catchments during the 2 y following forest harvest but prior to site preparation. This enabled us to separate the effect of the two operations that followed best management practices. Hg-tot concentrations increased by approximately 15%, and fluxes by 20-30%. The MeHg concentrations and fluxes either declined or increased by up to 60%, depending on whether annual MeHg peaks during summer low flows were considered to have been influenced by forest harvest. The lack of a severalfold increase in Hg outputs after forest harvest, as reported from other sites, may be the result of minimal soil disturbance during the winter forest harvest operations. If so, there may be a greater Hg response after soil scarification to prepare for planting
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| 38. |
- Tonderski, Karin S, et al.
(författare)
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Modeling the impact of potential wetlands on phosphorus retention in a Swedish catchment
- 2005
-
Ingår i: Ambio. - : Royal Swedish Academy of Sciences. - 0044-7447 .- 1654-7209. ; 34:7, s. 544-551
-
Tidskriftsartikel (refereegranskat)abstract
- In southern Sweden, wetlands are constructed to remove nitrogen (N) in agricultural catchments. The possible effects of such wetlands on riverine phosphorus (P) were also estimated using input-output data from three well-monitored wetlands. This was done to formulate a simple model for removal of P that is dependent on inflow characteristics. Next, the N- and P-reducing effects of wetlands were modeled on a catchment scale (1900 km 2) using the HBV-NP model and various assumptions about the wetland area and location. All three wetlands functioned as sinks for total P (tot-P) and for total suspended solids (TSS) with a removal of 10% to 31% and 28% to 50%, respectively. Mean P-removal rates of 17-49 kg ha(-1) yr(-1) were well simulated with the model. Catchment scale simulations indicated that wetlands were more efficient (in percentage of load) as traps for P than for N and that this may motivate the construction of wetlands for P removal far upstream from the catchment outlet.
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| 39. |
- Wittgren, Hans B, et al.
(författare)
-
An actor game on implementation of environmental quality standards for nitrogen in a Swedish agricultural catchment
- 2005
-
Ingår i: Ambio. - : Royal Swedish Academy of Sciences. - 0044-7447 .- 1654-7209. ; 34:3, s. 237-247
-
Tidskriftsartikel (refereegranskat)abstract
- Despite political efforts, diffuse pollution from agriculture continues to be the single largest source of nitrogen (N) emissions into the aquatic environment in many countries and regions. This fact, and the recent enactment of a new Swedish environmental code, led to the design of a study targeted at the evaluation of new N pollution abatement strategies. An actor game was chosen as the key component of the study, with a focus on four major goals: to test the implementability of legally binding environmental quality standards for nitrate concentration in groundwater and N transport to the sea, to find sets of agriculturally feasible and cost-effective measures to decrease N loads, to investigate the possibilities for collective action through negotiated and institutionalized actor cooperation, and to investigate the role of mathematical modeling in environmental N management. Characteristics from the agriculturally dominated catchment of Genevadsan (224 km(2)) on the southwest coast of Sweden served as the playing field for the actor game. The most noteworthy result from the study was that it appeared to be possible to meet ambitious environmental N standards with less economically drastic measures than anticipated by most of the participants. The actor game was shown to be a good method for learning about the new Swedish environmental code and its application and for gaining deeper insight into the issues of N management. In addition, the actor game functioned as an arena for gaining a more thorough understanding of the views of different stakeholders.
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| 40. |
- Öhman, Karin, et al.
(författare)
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An Approach for Including Consideration of Stream Water Dissolved Organic Carbon in Long Term Forest Planning
- 2009
-
Ingår i: AMBIO: A Journal of the Human Environment. - : Royal Swedish Academy of Sciences. - 0044-7447 .- 1654-7209. ; 38:7, s. 387-393
-
Tidskriftsartikel (refereegranskat)abstract
- The objective of this study was to add to a traditional forest planning model by incorporating some consideration of the effects of forestry on dissolved organic carbon (DOC) concentrations in streams over time. In a case study, for a watershed in northern Sweden, we present the best possible solution to a forest planning problem that maximizes the net present value (NPV) while the DOC concentration levels in the watershed are maintained below a defined threshold value. Results from the case study show that the decrease in NPV, when taking DOC into account, was considerable. However, the decrease in possible harvest volume was restricted in the case study area because the model moved harvesting activity from the first 20-year period to later periods to avoid high initial DOC concentrations. The model presented could be a useful tool for predicting the effect of forestry on DOC concentrations over time.
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| 41. |
- Brogaard, Sara, et al.
(författare)
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Rural reforms and changes in land management and attitudes: A case study from Inner Mongolia, China
- 2002
-
Ingår i: Ambio: a Journal of Human Environment. - 0044-7447. ; 31:3, s. 219-225
-
Tidskriftsartikel (refereegranskat)abstract
- The international science community stresses the importance of the local perspective in the context of dryland degradation. This paper explores changes in management and attitudes in a mixed farming system in northern China, since the introduction of the economic reforms in the early 1980s, and the following changes in land-use rights. The area encompasses a dune landscape scattered with crop-land, as well as the Daqinggou Nature Reserve, an area of natural vegetation. According to farmers new varieties of maize in combination with increased use of fertilizers have improved yields, though high yield variability persists due to erratic rainfall. Farmers acknowledge the importance of the 30-year contract on cultivated land in 1997 for their investment in long-term management, but emphasize the importance of chemical fertilizers for short-term economic survival. The farmers stressed the negative impact of grazing and cultivation on soil erosion and stated that differences in vegetation composition and cover in the nature reserve are due to anthropogenic factors.
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| 42. |
- Cuadra, Steven, et al.
(författare)
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Persistent organochlorine pollutants in children working at a waste-disposal site and in young females with high fish consumption in Managua, Nicaragua
- 2006
-
Ingår i: Ambio. - 0044-7447 .- 1654-7209. ; 35:3, s. 109-116
-
Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to assess persistent organochlorine pollutant (POP) levels in serum collected from children (11-15 years old) working and sometimes also living at the municipal waste-disposal site in Managua, located at the shore of Lake Managua, and in nonworking children living both nearby and also far away from the waste-disposal site. The influence of fish consumption was further evaluated by assessing POPS levels in serum from young women (15-24 years old) with markedly different patterns of fish consumption from Lake Managua. 2,2-bis(4-chlorophenyl)-1,1,1-trichloro-ethane (4,4’-DDT) and 2,2-bis(4-chlorophenyl)-1,1-dichloro-ethene (4,4-DDE), T-hexachlorocyclohexane (gamma-HCH), polychlorinated biphenyls, pentachlorophenol, and polychlorobiphenylols were quantified in all samples. In general, the levels observed were higher than those reported in children from developed countries, such as Germany and United States. Toxaphene, aldrin, dieldrin, and beta-HCH could not be identified in any sample. The children working at the waste-disposal site had higher levels of POPS compared with the nonworking reference groups. In children not working, there were also gradients for several POPs, according to vicinity to the waste-disposal site. Moreover, in children, as well as in young women, there were gradients according to fish consumption. The most abundant component was 4,4-DDE, but at levels still lower than those reported in children from malarious areas with a history of recent or current application of 4,4-DDT for vector control.
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| 43. |
- Johansson, Margareta, et al.
(författare)
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What determines the current presence or absence of permafrost in the Tornetrask region, a sub-arctic landscape in Northern Sweden?
- 2006
-
Ingår i: Ambio: a Journal of Human Environment. - 0044-7447. ; 35:4, s. 190-197
-
Tidskriftsartikel (refereegranskat)abstract
- In a warming climate, permafrost is likely to be significantly reduced and eventually disappear from the sub-Arctic region. This will affect people at a range of scales, from locally by slumping of buildings and roads to globally as melting of permafrost will most likely increase the emissions of the powerful greenhouse gas methane, which will further enhance global warming. In order to predict future changes in permafrost, it is crucial to understand what determines the presence or absence of permafrost under current climate conditions, to assess where permafrost is particularly vulnerable to climate change, and to identify where changes are already occurring. The Tornetrask region of northern sub-Arctic Sweden is one area where changes in permafrost have been recorded and where permafrost could be particularly vulnerable to any future climate changes. This paper therefore reviews the various physical, biological, and anthropogenic parameters that determine the presence or absence of permafrost in the Tornetrask region under current climate conditions, so that we can gain an understanding of its current vulnerability and potential future responses to climate change. A patchy permafrost distribution as found in the Tornetrask region is not random, but a consequence of site-specific factors that control the microclimate and hence the surface and subsurface temperature. It is also a product of past as well as current processes. In sub-Arctic areas such as northern Sweden, it is mainly the physical parameters, e.g., topography, soil type, and climate (in particular snow depth), that determine permafrost distribution. Even though humans have been present in the study area for centuries, their impacts on permafrost distribution can more or less be neglected at the catchment level. Because ongoing climate warming is projected to continue and lead to an increased snow cover, the permafrost in the region will most likely disappear within decades, at least at lower elevations.
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| 44. |
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| 45. |
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| 46. |
- Andersson, Mathias H, 1976-, et al.
(författare)
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Swimming Behavior of Roach (Rutilus rutilus) and Three-spined Stickleback (Gasterosteus aculeatus) in Response to Wind Power Noise and Single-tone Frequencies
- 2007
-
Ingår i: Ambio. - 0044-7447 .- 1654-7209. ; 36:8, s. 636-638
-
Tidskriftsartikel (refereegranskat)abstract
- Human-induced underwater noise is drastically increasing as the result of offshore installations and human activities in the marine environment. Many of these structures and activities produce low-frequency noise that could potentially disturb or have harmful effects on several species of teleost fishes. Within the next decade, thousands of wind turbines will be in use in coastal and offshore waters and there is increasing concern on how they may influence marine life. The aims of this study were to examine how swimming behavior of roach (Rutilus rutilus) and three-spined stickleback (Gasterosteus aculeatus) were influenced by single-frequency sounds and noise generated by an offshore wind turbine, and the function of sound pressure level.
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| 47. |
- Back, Pär-Erik, 1961, et al.
(författare)
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Value of Information Analysis in Remedial Investigations
- 2007
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Ingår i: Ambio. - 0044-7447 .- 1654-7209. ; 36:6, s. 486-493
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Tidskriftsartikel (refereegranskat)abstract
- Site investigations of contaminated land are associated with high costs. From a societal perspective, just enough economic resources should be spent on investigations so that society's limited resources can be used optimally. The solution is to design investigation programs that are cost-effective, which can be performed using Value of Information Analysis (VOIA). The principle of VOIA is to compare the benefit at the present state of knowledge with the benefit that is expected after an investigation has been performed. A framework for VOIA of site investigations is presented based on Bayesian risk-cost-benefit decision analysis. The result is an estimate of the value of an investigation program, and for specific problems, the optimal number of samples. The main strength of the methodology is that it promotes clear thinking and forces the decision-maker to reflect on issues that otherwise would be ignored. The main weakness is the complexity of VOIA models.
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| 48. |
- Bindler, Richard, et al.
(författare)
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Pre-industrial atmospheric pollution: Was it important for the pH of acid-sensitive Swedish lakes?
- 2002
-
Ingår i: Ambio. - 0044-7447. ; 31:6, s. 460-465
-
Tidskriftsartikel (refereegranskat)abstract
- Acid rain has caused extensive surface water acidification in Sweden since the mid-20(th) century. Sulfur emissions from fossil-fuel burning and metal production were the main sources of acid deposition. In the public consciousness acid deposition is strongly associated with the industrial period, in particular the last 50 years. However, studies of lake-water pH development and atmospheric pollution, based on analyses of lake sediment deposits, have shown the importance of a long-term perspective. Here, we present a conceptual argument, using the sediment record, that large-scale atmospheric acid deposition has impacted the environment since at least Medieval times. Sulfur sources were the pre-industrial mining and metal industries that produced silver, lead and other metals from sulfide ores. This early excess sulfur deposition in southern Sweden did not cause surface water acidification; on the contrary, it contributed to alkalization, i.e. increased pH and productivity of the lakes. Suggested mechanisms are that the excess sulfur caused enhanced cation exchange in catchment soils, and that it altered iron-phosphorus cycling in the lakes, which released phosphorus and increased lake productivity
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| 49. |
- Björn, Erik, et al.
(författare)
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Recent Advances in Mercury Speciation Analysis with Focus on Spectrometric Methods and Enriched Stable Isotope Applications
- 2007
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Ingår i: Ambio. - 0044-7447 .- 1654-7209. ; 36:6, s. 443–51-
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Tidskriftsartikel (refereegranskat)abstract
- This paper discusses some recent advances in spectrometric methods and approaches for mercury speciation analysis of environmental samples with focus on isotope dilution techniques for determination of mercury species' concentrations in gaseous samples and reaction rates in soils and sediments. Such analytical data is important inter alia in fundamental research on mercury biogeochemistry and for risk assessments of mercury-contaminated soils and sediments and for designing effective remedial actions. The paper describes how the use of enriched stable isotope tracers in mercury speciation analysis can improve the traceability and accuracy of results, facilitate rational method developments, and be useful for studying biogeochemical processes, i.e. rate of reactions and fluxes, of mercury species. In particular the possibilities to study and correct for unwanted species transformation reactions during sample treatment and to study “natural” transformations of species in environmental samples, or micro- and mesocosm ecosystems, during incubations are highlighted. Important considerations to generate relevant data in isotope tracer experiments as well as reliability and quality assurance of mercury speciation analysis in general are also discussed.
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| 50. |
- Ekström, Magnus, 1966-
(författare)
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Quantifying spatial patterns of landscapes
- 2003
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Ingår i: Ambio. - 0044-7447 .- 1654-7209. ; 32:8, s. 573-576
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Tidskriftsartikel (refereegranskat)abstract
- In this paper we discuss information theoretical landscape indices based on data from digitized maps in grid format: measures based on Shannon's entropy, e.g. the measures of diversity and contagion; and measures based on conditional entropy, e.g. a new index which can be seen as an alternative to the measure of contagion that does not have the disadvantage of being highly correlated to the measure of diversity. We also introduce a measurement on how much information Is contained in a coarse-scale map about a fine-scale map.
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