Spelling suggestions: "subject:"baltic seja""
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Brominated natural products at different trophic levels in the Baltic Sea : Identification of polybrominated dioxins, hydroxylated and methoxylated diphenyl ethersMalmvärn, Anna January 2007 (has links)
<p>Over time, the Baltic Sea has been contaminated by increasing discharges of pollutants from human activities. Persistent organic pollutants (POPs) have caused toxic effects in wildlife and excess of nutrients have led to eutrophication. Furthermore, there are indications that certain polyhalogenated compounds similar in structure to man-made POPs are produced by the biota present in this sea. In the late 1990’s both methoxylated polybrominated diphenyl ethers (MeO-PBDEs) and hydroxylated-PBDEs (OH-PBDEs) were identified in fish and seals living in this environment. OH-PBDEs can originate from metabolism of PBDEs, but both OH- and MeO-PBDEs are also known to be natural products in marine environments. Another group of POPs, the polybrominated dibenzo-<i>p</i>-dioxins (PBDDs), are not produced commercially, but are known to be by-products of chemical industry and of the combustion of, e.g., brominated flame retardants (BFRs). In contrast to the OH- and MeO-PBDEs, PBDDs have not previously been shown to be natural products, although certain related compounds have been indicated to have a natural origin.</p><p>This thesis describes the identification of PBDDs, OH-PBDEs and MeO-PBDEs in algae, blue mussels and fish living in the Baltic Sea. Several of these compounds were also detected in cyanobacteria. Moreover, PBDDs were present in fish, mussels, shrimp and crabs from different regions of the Baltic Sea and from the west coast of Sweden, but not in organisms from freshwater environments. The levels of these compounds in Baltic fish generally exceeded those of their chlorinated analogues. The origin of the PBDDs identified is somewhat unclear, but the high levels present in blue mussels and the pattern of congeners observed indicate natural production. The presence of PBDDs, OH-PBDEs and MeO-PBDEs in fish and shellfish constitutes a potential risk to both humans and wildlife and requires further investigation.</p>
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Ecotoxicological effects from three antifouling paints on the red macroalga <em>Ceramium tenuicorne.</em>Krantz-Frid, Madelene January 2009 (has links)
<p>Antifouling paints are applied on vessels to prevent growth of fouling organisms such hasbarnacles. Presently, there are a number of different paints available on the Swedish marketwith different strategies and active substances. The paints might work by either continuouslyreleasing biocides or physically by peeling off or provide an easily cleansed surface whereorganisms cannot attach. The physically working paints do not need to register an activesubstance since its purpose is not to affect living organisms by a chemical or biological modeof action. In this study, two commercially available paints, the copper-based Fabi 3959(International Paint Ltd) and physically eroding, biocide-free labelled Mille Light (HempelFärg AB) were compared to Hard Racing superior, containing copper and the forbiddensubstance Tributyltin. Fabi International is only allowed to be used on the Swedish west coastdue to 6% added as active substance while the biocide-free Mille Light is eligible for eastcoast usage. The toxic effect from respective paint was investigated by assembling a growthinhibition test with the red macro alga Ceramium tenuicorne. The results show that all thestudied paints had a negative effect on growth and therefore leaked substances inconcentrations high enough to be harmful to the alga. The toxic response differed with theeffect on growth being in the following order, Hard racing superior>Fabi >Mille Light.Implications regarding the current legalization involving biocide-free labelled antifoulingpaints are discussed.</p>
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Changes in condition of herring (<em>Clupea harengus</em>) in Swedish coastal watersPersson, Martin January 2010 (has links)
<p>The condition of the herring (<em>Clupea harengus</em>) in the Baltic Sea has decreased during the past 30-40 years. This decrease could be explained by different factors; (1) change in diet due to changes in zooplankton community, (2) changes in water temperature and salinity, (3) increasing nutrient inputs and (4) competition for food with other species such as sprat (<em>Sprattus sprattus</em>). In this study the change in condition was analysed using the Fulton’s condition index, and by looking at age and sex of the fish as well as the season and locationthe fish was caught, the differences between these factors were presented. Data from the national Swedish contaminant monitoring programme where used from four locations in the Baltic Sea and two locations at the Swedish West coast. The data was analysed using multiple regressions in R Commander. The result show that the condition, and the temporal trends in condition value, varies at different locations, with higher condition values and increasing temporal trends at the Swedish West coast, compared to the Baltic Sea with lower condition values and where three of four locations show decreasing temporal trends. The condition varied between spring and autumn caught herring as well, while age and sex showed less significant differences.</p>
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Brominated natural products at different trophic levels in the Baltic Sea : Identification of polybrominated dioxins, hydroxylated and methoxylated diphenyl ethersMalmvärn, Anna January 2007 (has links)
Over time, the Baltic Sea has been contaminated by increasing discharges of pollutants from human activities. Persistent organic pollutants (POPs) have caused toxic effects in wildlife and excess of nutrients have led to eutrophication. Furthermore, there are indications that certain polyhalogenated compounds similar in structure to man-made POPs are produced by the biota present in this sea. In the late 1990’s both methoxylated polybrominated diphenyl ethers (MeO-PBDEs) and hydroxylated-PBDEs (OH-PBDEs) were identified in fish and seals living in this environment. OH-PBDEs can originate from metabolism of PBDEs, but both OH- and MeO-PBDEs are also known to be natural products in marine environments. Another group of POPs, the polybrominated dibenzo-p-dioxins (PBDDs), are not produced commercially, but are known to be by-products of chemical industry and of the combustion of, e.g., brominated flame retardants (BFRs). In contrast to the OH- and MeO-PBDEs, PBDDs have not previously been shown to be natural products, although certain related compounds have been indicated to have a natural origin. This thesis describes the identification of PBDDs, OH-PBDEs and MeO-PBDEs in algae, blue mussels and fish living in the Baltic Sea. Several of these compounds were also detected in cyanobacteria. Moreover, PBDDs were present in fish, mussels, shrimp and crabs from different regions of the Baltic Sea and from the west coast of Sweden, but not in organisms from freshwater environments. The levels of these compounds in Baltic fish generally exceeded those of their chlorinated analogues. The origin of the PBDDs identified is somewhat unclear, but the high levels present in blue mussels and the pattern of congeners observed indicate natural production. The presence of PBDDs, OH-PBDEs and MeO-PBDEs in fish and shellfish constitutes a potential risk to both humans and wildlife and requires further investigation.
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Politique étrangère francaise en mer Baltique (1871-1914) : De l'exclusion à l'affirmation / French foreign policy in the Baltic sea area (1871-1914) : From exclusion to assertionFraudet, Xavier January 2005 (has links)
This thesis is a contribution to the study of French foreign policy in the time of “old diplomacy” in Northern Europe. Aiming to fill a gap, the object of investigation is French foreign policy in the Baltic area between 1871 and 1914 (from the French defeat during the Franco-Prussian War to the outbreak of the First World War). Particular attention is directed at the assets of the French diplomacy at work in the Baltic Sea: naval military planning, financial loans and culture. Since the period was dominated by the diplomatic isolation that Bismarck had placed France with the aim to prevent her from creating any kind of alliance to embark in a war of revenge against Germany, France carried out a policy of making ententes and alliances in order to break out from this isolation. However, in her attempt to emerge, France was challenged by Germany especially in relations with Denmark and Sweden. Although French foreign policy was able to use the loan as an instrument to secure a success with Russia by establishing a military treaty in 1892, but France did not succeed to attract and influence Sweden in the same way because of the risk of her turning to Germany. Also strongly challenged by Germany in Denmark, French foreign policy could not stop the willingness of Denmark to adopt a policy of neutrality. But, because of her intervention between Russia and Great Britain in the Dogger Bank incident in 1904, French diplomacy succeeded to gain the support of the British fleet in the case of a naval war in the Baltic Sea for operations against the German coast. Bringing together Russia and Great Britain for a naval cooperation in the case of a war in the Baltic Sea was, without any doubt, not only the most audacious and difficult task for French foreign policy, but also a sign of its strong revival. However, this Russo-British naval cooperation could not be converted into practice because of the geographical specificities of the Baltic Sea and the difficulties of naval military planning. Adressing this aspect, this thesis reveals the fundamental mistakes of the naval theoreticians who were defending naval theories based on land military theories and experiences.
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Nitrogen land-sea fluxes in the Baltic Sea catchment : Empirical relationships and budgetsEriksson Hägg, Hanna January 2010 (has links)
In this thesis empirical relationships and modeling tools are used to describe the relationship between human activities and meso- and large scale riverine N fluxes from land to sea. On a large scale Paper I showed that by only having knowledge about human population size and runoff one can estimate the riverine export of DIN (r2= 0.76). In Paper II we included two other important anthropogenic N inputs, i.e. atmospheric deposition and primary emission (PE) from animals. In most of the catchments the PE from animals were larger than the PE from humans. Hence, development of livestock is important and increased animal protein consumption by humans might increase the riverine N export. Scenario analysis (Paper II) show that climate change is expected to both decrease and increase the riverine N export depending on which part of the catchment is modeled. In the southern and eastern parts of the Baltic Sea catchment there is large potential for N reductions from point sources (Papers III & V). The diffuse sources are more difficult to decrease and a reduction of mineral fertilizer does not always lead to reduced N loadings because the agricultural systems can buffer even a slight surplus (Paper III). There is inertia in the catchments which can be seen in for example in the northern part of the catchment. Here atmospheric N deposition is almost as high as in the southern part but the nitrogen flux from these rivers is not elevated. These northern river catchments have N exports of the same magnitude as the natural background (Paper IV), indicating that the atmospheric N deposition is retained in the system and probably taken up by N limited boreal forests. However, important reductions can be achieved in the agricultural sector by detailed management of the planted land and animal manure. The highest sensitivity is in catchments with high animal density and high specific discharge, primarily draining to Kattegat and Danish Straits (Paper II & IV). / At the time of doctoral dissertation the following publications were unpublished and had a status as follows: Paper 2: Manuscript. Paper 4: Manuscript
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Ridged sea ice modelling in climate applicationsMårtensson, Sebastian January 2013 (has links)
This work aims to increase our understanding of the nature of large scale features of sea ice from a dynamics point of view.Sea ice plays an important part in the exchange of heat and humidity between sea and air and thus is an important component of the climate system. Its physical presence also directly impacts the various forms of life such as diatoms, polar bears and humans alike.The dynamics of sea ice affect both weather and climate, through the large scale drift in the Arctic from the Siberian coast towards Fram Strait, through creation of cracks in the ice called leads or polynyas, and through ridging and other mechanical deformations of ice floes.In this work, we have focused on modelling of ridged ice for a number of reasons. Direct observations of the internal ice state is very difficult to perform and in general, observations of sea ice are either sparse or of limited information density. Ridged ice can be seen as the memory of high ice stress events, giving us a view on these highly dynamic events. Ridging is of major importance for the ice thickness distribution, as the thickest ice can only be formed through mechanical processes. Further, ridged ice is of direct interest for anyone conducting shipping through seasonal or perennial ice covered seas as it can form impenetrable barriers or in extreme even cases crush a ship caught within the ice pack. To this end, a multi-category sea ice model, the HELsinki Multi category Ice model (HELMI), was implemented into the Rossby Centre Ocean model (RCO). HELMI has explicit formulations for ridged and rafted ice, as well as sub-grid scale ice thickness distribution (a feature shared with other multi category models) and an ice strength based on energetics. These features give RCO better representation of sub-grid scale physics and gives us the possibility to study the deformed ice in detail. In paper I we look at the change in behaviour in the Arctic as the ice becomes more mobile, leading to a slight increase in modelled ridged ice volume in the central Arctic, despite a general trend of a decreasing ice cover.Paper II takes us to the Baltic Sea and the possibilities of modelling ridge ice concentration with a statistical model.In Paper III we investigate how the diminishing ice cover in future scenarios affects the biological activity in the Baltic Sea.Finally Paper IV investigates how the ice stress and the internal ice force can be interpreted in terms of ice compression on the ship scale. / <p>At the time of the doctoral defence the following paper was unpublished and had a status as follows: Paper 4: Manuscript</p>
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Grave fra Østersøområdet i Boreal og tidlig Atlantisk tid : et multiregionalt studie / Early Mesolithic burials from the area around the Baltic Sea : a multiregional studyFrydendal Nielsen, Katrine January 2012 (has links)
The aim of this paper is to examine if any homogeneity or heterogeneity can be traced in burials from Preboreal, Boreal and Early Atlantic period, in the area of the Baltic Sea. Furthermore, the paper will deal with the Early Mesolithic burials based on theoretical perspectives on rituals, materiality and agency.To enable the purpose of identifying the homogeneity or heterogeneity of the data, relational multi-varied Correspondence Analysis of the individuals and their artifact variations, body position, burial type etc. have been applied.The data used in this study contain information from 41 sites including 171 graves with 194 individuals from nine different countries (Denmark, Finland, Germany, Latvia, Lithuania, Norway Poland, Russia and Sweden). The study is based on the work Mesolithische Bestattungen in Europa. Ein Beitrag zur vergleichenden Gräberkunde. Teil I-II of Judith M. Grünberg from 2000, however some new sites and graves have been added.This study is expected to contribute new contextual interpretations of the Early Mesolithic burials of the area of the Baltic Sea.
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Changes in condition of herring (Clupea harengus) in Swedish coastal watersPersson, Martin January 2010 (has links)
The condition of the herring (Clupea harengus) in the Baltic Sea has decreased during the past 30-40 years. This decrease could be explained by different factors; (1) change in diet due to changes in zooplankton community, (2) changes in water temperature and salinity, (3) increasing nutrient inputs and (4) competition for food with other species such as sprat (Sprattus sprattus). In this study the change in condition was analysed using the Fulton’s condition index, and by looking at age and sex of the fish as well as the season and locationthe fish was caught, the differences between these factors were presented. Data from the national Swedish contaminant monitoring programme where used from four locations in the Baltic Sea and two locations at the Swedish West coast. The data was analysed using multiple regressions in R Commander. The result show that the condition, and the temporal trends in condition value, varies at different locations, with higher condition values and increasing temporal trends at the Swedish West coast, compared to the Baltic Sea with lower condition values and where three of four locations show decreasing temporal trends. The condition varied between spring and autumn caught herring as well, while age and sex showed less significant differences.
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Hantering av toalettavfall från fritidsbåtar : Undersökning om dagens vattenbehandlingssystem för att minska övergödning i ÖstersjönJohansson, Adam January 2015 (has links)
The eutrophication in the Baltic Sea is a big issue which threatens marine ecosystems, increases the depletion of oxygen in the water and causes harm to aquatic animals. Human activities such as industries, agriculture, forestry and untreated sewage increase nutrient input (mainly nitrogen and phosphorus) which causes increased levels of plankton and bacteria. Sweden has suggested to prohibit recreational craft owners to discharge their untreated wastewater to the ocean. The aim for this study is to examine and analyze the different types of water treatment systems that exist today and to see what levels of bacteria and nutrients the effluent water has from the systems. This research will help the EU-commission to decide what demands you can put on the discharged effluent water on recreational crafts. The study shows that none of the existing systems is able to decrease the levels of nutrients in the effluent treated wastewater. This makes it hard for the EU-commission to decide on demands for recreational crafts. This may lead to increased use of drainstations of wastewater in harbors for owners.
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