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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

River Lamprey Lampetra fluviatilis (L.) Fishing in the Area around the Baltic Sea

Sjöberg, Kjell January 2011 (has links)
The river lamprey (Lampetra fluviatilis) was previously caught in large numbers in Europe when migrating up in the rivers during autumn for spawning the next spring. It was used as food and was also used as bait in cod fishing in the North Sea. Today the river lamprey has decreased in numbers over much of it’s distribution range, but in the Baltic Sea area, the population is still at a fairly good level, and fishing for lampreys as food (a tradition going back to at least the fifteenth century) is still going on in northern Swedish and Finnish rivers, as well as in coastal rivers in the southern Baltic Sea area. In this article the current situation as regards river lamprey fishing in Sweden, Finland, Latvia and, to some extent, Estonia, Lithuania and Poland is presented.
72

Practical applications for an actomyosin-based biosensor in Baltic Sea water

Pennsäter, Maria January 2013 (has links)
Seawater and wastewater all around the world contain toxins and pollutants, not the least drug residues, including hormoneswhich disturb the ecosystems and antibiotics with growing multi-drug resistance of bacteria as a result. The effects onecosystems and mankind can be severe and with this general fact the need for proper analysis devices increases. This haspromoted further studies to establish devices for detection of analytes with high selectivity and high sensitivity. In this thesis Ipresent a unique device exploiting capture of antigen on antibody conjugated actin filaments and subsequent transportationof the antigen in Baltic Sea water using heavy meromyosin (HMM) motor fragments from muscle myosin. The model-antibody,anti-rIgG, used in the study, was covalently attached to the actin filaments, capturing a model-analyte, rIgG that was dissolvedin the Sea water. Furthermore, the effect of Baltic Sea water on HMM propelled actin filament transportation in the in vitromotility assay was studied. An effect was observed with Baltic Sea water, supplemented with standard adenosine 5’-triphosphate (ATP) and oxygen scavenger systems, reducing the sliding velocity by approximately 80%. However the effect wasreversible which is of great advantage in relation to the development of a future biosensor device incorporating actomyosindriven transports. Additionally, evidence was found that the substance A slightly enhanced the function of the proteins whenstored on a motility assay surface at 4-8 °C for up to ten days, of value for practical applications of a potential biosensordevice. The results demonstrate the potential that antigen from sea water could be captured and transported by actomyosinto certain detector areas and eventually become concentrated which would increase the sensitivity of the device.
73

Isotope-based reconstruction of the biogeochemical Si cycle : Implications for climate change and human perturbation

Sun, Xiaole January 2012 (has links)
The global silicon (Si) cycle is of fundamental importance for the global carbon cycle. Diatom growth in the oceans is a major sequestration pathway for carbon on a global scale (often referred to as the biological pump). Patterns of diatoms preserved in marine sediment records can reveal both natural and anthropogenic driven environmental change, which can be used to understand silicon dynamics and climate change. Si isotopes have been shown to have great potential in order to understand the Si cycle by revealing both past and present patterns of dissolved Si (DSi) utilization, primarily when diatoms form their siliceous frustules (noted as biogenic silica, BSi). However, studies using Si isotopes are still scarce and only a few studies exist where stable Si isotopes are used to investigate the biogeochemical Si cycle in aquatic systems. Therefore, this thesis focuses on developing analytical methods for studying BSi and DSi and also provides tools to understand the observed Si isotope distribution, which may help to understand impacts of climate change and human perturbations on marine ecosystems. The Baltic Sea, one of the biggest estuarine systems in the world, was chosen as the study site. BSi samples from a sediment core in Bothnian Bay, the most northern tip of the Baltic Sea, and diatom samples from the Oder River, draining into the southern Baltic Sea were measured and reported in Paper II and III, after establishing a method for Si isotope measurements (Paper I). Si isotope fractionation during diatom production and dissolution was also investigated in a laboratory-controlled experiment (Paper IV) to validate the observations from the field. The major result is that Si isotope signatures in BSi can be used as an historical archive for diatom growth and also related to changes in climate variables. There is isotopic evidence that the Si cycle has been significantly altered in the Baltic Sea catchment by human activities. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript.</p>
74

The distribution of bronze artefacts of Viking Age Eastern Baltic types discovered on Gotland : Iron Age networks and identities

Gunnarsson, Daniel January 2013 (has links)
This thesis has compared the distribution of certain types of Viking Age Eastern Baltic bronze artefacts discovered on Gotland. This was done in order to observe different parts of Gotland´s interaction with different groups in the Baltic Sea region and how this might have influenced the identities and ideas of the individuals involved in the interaction. The objects and their finding contexts were subjected to a geographical analysis and applied to a map of Viking Age Gotland. Different distribution patterns can be observed for different types of artefacts, as well as a shift in pattern of interaction in the Baltic Sea region over time.
75

Cruise tourism on the Baltic Sea and implications of water quality legislation : A case study on balancing the interests of the cruise industry and local economies with long-term environmental sustainability

Polack Huamán de Duijvelaar, Sandy January 2012 (has links)
No description available.
76

Födosammansättning hos gråsäl (Halichoerus grypus) samt test av flotte för insamling av sälfekalier.

Lagström, Christian January 2008 (has links)
During the 1960´s and 1970´s the number of grey seals in the Baltic Sea was decreasing rapidly, mostly due to hunting and toxic substances like DDT and PCB. When hunting became less intense and toxic substances decreased in the environment the grey seal population started to increase. Today grey seals are found common in the Baltic Sea and have started to become a big treat and a problem to the fishing industry. The grey seal destroys and enters fishing traps and consumes large quantities of the fish that have been caught. The knowledge of the grey seal, like abundance and food preferences, is today limited. It is also important to define the position of the grey seal in the ecosystem in the Baltic Sea and to be able to predict changes that could occur if the population would rapidly decrease or increase. This project was therefore started in an attempt to increase the knowledge about the grey seals food preferences. The study was made in tree separate parts. Part one contained analyses of prey remains from stomachs and digestive tract from fourteen individuals put down in two geographically separate areas. The collected material from the seal digestive tract was cleaned and otoliths (hearing stones from fish), scales and back vertebra from fish eaten by the grey seal were sorted out. With the help of hard parts collected from the intestines the food preferences of the seals could be estimated. Eight different species of prey was found. The species were herring (Clupea harengus membras), sprat (Sprattus sprattus), common whitefish (Coregonus spp), perch (Perca fluviatilis), salmon (Salmo salar), trout (Salmo trutta) and roach (Rutilus rutilus). In two of the digestive tracts several individuals of the isopod Saduria entomon were found. No earlier studies describe the isopod as a food source for the grey seals in the Baltic Sea. The findings are therefore unique information. The results showed that during summer the main part of the grey seal diet in the gulf of Sundsvall and in the surrounding coastal area of Hårte was herring and sprat. No significant difference in food preferences was shown between the investigated seals from the gulf of Sundsvall and seals from the surrounding coastal area of Hårte. The second part was made to investigate if it was possible to build a floating platform that would work as a resting place for the grey seal. The surface of the platform was covered by a layer that keeps the seal scats on the platform so that it could be collected. Otoliths from herring and common whitefish were found on the floating platform. Because the platform could not be under surveillance during the whole study some uncertainties about whether the otoliths found came from grey seal or from resting cormorants or other fish eating birds. However, the otolit size is linearly related to the fish size and this relationship can be used to track the predator. Otoliths from herring taken by grey seals and otoliths found on the platform were significantly bigger than the otoliths originating from the prey of cormorants. The results indicated that the common whitefish size was too big for a full grown cormorant bird to consume. The common whitefish size showed that it probably not had been cormorants that had deposited the otoliths on the platform. The platform method was concluded promising but it needs to be modified in order to work more effective in the future. In the third part scats were collected from the area of Österåsen to increase the amount of information about the grey seals food preferences. The knowledge of the grey seals diet in the Baltic Sea is today limited and few similar study’s have earlier been made. The collected scats and otoliths in this project are therefore unique. 2008:Bi 2
77

Preventive action in the protection of the Baltic Sea : Do the HELCOM Baltic Sea Action Plan and An Agenda for the Baltic Sea Region – Baltic 21 advocate preventive action in protecting the Baltic Sea?

Lundgren, Lina January 2008 (has links)
<p>The Baltic Sea is a sensitive and unique ecosystem that has been strongly affected by human activity in the area. It is an important cultural and natural resource that contributes with several economic benefits. Among the many documents aiming to protect the Baltic Sea, this thesis concerns two of the action plans; An Agenda for the Baltic Sea Region – Baltic 21 and HELCOM Baltic Sea Action Plan, which are two of the most recognised documents aiming at protecting the Baltic Sea area. The two documents was analysed using three different types of text analysis.</p><p>As the main goal in all environmental protection is to urge preventive action in protecting the environment, the two documents will be analysed with the aim of investigating whether preventive action is advocated in the protection of the Baltic Sea, even though the region is threatened and have many problems from an environmental point of view.</p><p>The two documents differ structurally as their approaches differ. The HELCOM Baltic Sea Action Plan (BSAP) has an ecosystem approach, whiles the Baltic 21 has sustainable development as its primarily approach. The results of the study further show that preventive action is advocated in both documents. However, the BSAP presents a cleared preventive approach and suggests more preventive action than Baltic 21. Baltic 21 lack a clear connection to the Baltic Sea and instead focus in the whole Baltic Sea area. There are few clearly preventive action presented in the protection of the actual Baltic Sea in Baltic 21. Instead the Baltic 21 shows a vague argumentation and few actions aiming at preventing environmental harm to the Baltic Sea.</p>
78

Biomarkers for exposure and for the effects of contamination with polyhalogenated aromatic hydrocarbons in Baltic ringed and grey seals /

Nyman, Madeleine. January 2000 (has links)
Thesis (Ph. D.)--University of Helsinki, 2000. / Includes bibliographical references (p. 35-43). Also available in electronic format via Internet.
79

Nord Stream dujotiekio projektas ir Baltijos jūros regiono šalys / The Nord Stream gas pipeline project and states of the Baltic sea region

Mockus, Artūras 09 June 2008 (has links)
Pastaruoju metu nevengiama pabrėžti, kad keičiasi valstybių saugumo pobūdis ir grėsmių specifika – dažnai ir išsamiai kalbama apie tradicinių, karinių grėsmių reikšmės sumažėjimą ir naujo tipo grėsmių atsiradimą. Dar visai neseniai ryšys tarp energetikos ir užsienio bei saugumo politikos nebuvo nei toks akivaizdus, nei taip stipriai akcentuojamas. Tačiau per pastaruosius kelerius metus tarptautinė situacija dėl energijos apsirūpinimo smarkiai pasikeitė. Garantuotas energetinių išteklių tiekimas stabiliomis kainomis tapo rimta tarptautinių santykių problema. Europos Sąjungos priklausomybė nuo Rusijos energijos šaltinių ypač padidėjo. Jau šiuo metu apie 40 procentų dujų ir apie trečdalį naftos daugelis ES �����alių gauna iš Rusijos, kitos, sakykim, Lenkija ar Baltijos valstybės, – dar daugiau. Lietuva jau ir šiandien yra per daug priklausoma nuo Rusijos energetinių išteklių, o kai bus uždaryta Ignalinos atominė elektrinė, priklausomybė nuo išorinių šaltinių - o tai reiškia, nuo Rusijos - dar padidės. Rusijai ir Vokietijai Baltijos jūros dugnu nutiesus Šiaurės Europos dujotiekį, Lietuva taps dar labiau izoliuota Europos „energetinė sala”. ES nesugeba suformuoti vieningos ES energetinės politikos Rusijos atžvilgiu, nes dauguma ES narių vis dar yra linkusios palaikyti joms palankų dvišalį dialogą su Rusija, neretai neatsižvelgdamos į kaimyninių valstybių ar ES interesus plačiąja prasme. Dėl to atskirų ES valstybių energetinė priklausomybė nuo Rusijos yra linkusi didėti. Tuo pačiu... [toliau žr. visą tekstą] / Energy security is, at its essence, an issue of national security. Due to the power that energy-producing states have relative to transit and consumer countries, energy security must be understood in terms of geopolitics. The gas cutoff to Ukraine on January 1, 2006 is often called a “wake-up moment” for Europe, in other words, the point at which Europeans became aware of their over-dependence on Russian gas. Recognizing the risk, that East and Central Europe countries will have difficulty resisting Russian political and economic pressure, US Vice President Dick Cheney underlined on May 4 at the 2006 Vilnius Conference that “No legitimate interest is served when oil and gas become tools of intimidation or blackmail, either by supply manipulation or attempts to monopolize transportation.” That said, and while countries ranging from Central Asia to the Baltic Sea want to diversify their sources away from Russia, to date, there is still no coherent energy security policy in Europe or the US. Despite some recent efforts, a real common energy strategy of the European Union is still in the making. Every single EU-member has therefore opted for bilateral policies towards energy exporters in order to tackle mounting energy demands at a time when global hydrocarbon resources are slowly but steadily being depleted. Europe is wedged between energy producers in the North Sea, North Africa and the Middle East, but Russia has come to be one of the most interesting exporters of energy to... [to full text]
80

Towards a sustainable food system : On entrepreneurship, resilience and social capital in Baltic Sea agriculture

Larsson, Markus January 2013 (has links)
This thesis presents a comparison of conventional agriculture and Ecological Recycling Agriculture (ERA) in terms of their environmental and socio-economic effects. Environmental effects include greenhouse gas emissions and energy use but the focus is on leakage of nutrients. Socio-economic effects include production, costs and benefits at macro, firm and household levels. The comparison is made at regional (Baltic Sea), national (Swedish) and local (Järna community/Södertälje municipality) levels. At regional level the main challenge is to transform agricultural production in an environmentally friendly direction and reduce nutrient loads while sustaining food production. At national level the challenges are to shift the product mix towards more vegetables and less meat, and to address the geographical division of animal and crop production. At local level the challenge is to achieve sustainable rural development in environmental, economic and social terms. Results: at regional level the empirical findings were scaled up to calculate three scenarios. A scenario where the agriculture sectors of Poland and the Baltic States transform in such a way that their structure and use of resources resembles the Swedish average resulted in a 58% increase of nitrogen and an 18% increase in phosphorus surplus from agriculture and increased food production. Two other scenarios where agriculture in the entire Baltic Sea area converts to ERA resulted in reductions of 47-61% in nitrogen surplus from agriculture and eliminated the phosphorus surplus. In these scenarios food production decreased or remained stable depending on the strategy chosen. At national level, the environmental effects of different production methods, transport and different food baskets were compared. A household survey was performed to construct an alternative food profile. This food basket was high in vegetables, low in meat and high in locally produced organic food compared to the average Swedish food profile. It was also 24% more expensive. Food basket content was found to be as important as production methods in reducing the environmental effects. Localized production and processing was less important. At local level, a network of entrepreneurs engaged in the production, processing and distribution of organic food was studied. Semi-structured interviews were used to assess the network, which was found to be a resilient self-organized network characterized by economic stability and social capital. A high share of locally produced and consumed food was coupled with social and economic sustainability. This was facilitated by well-functioning cooperation within the network and between entrepreneurs, consumers and the municipality. EU expansion can be seen as a window of opportunity for governance of the Baltic Sea and the agriculture sector. A new agricultural regime with large-scale ERA production would result in several environmental gains. Sustainable governance of the Baltic Sea as agreed on in HELCOM cannot be achieved while simultaneously maximizing agricultural production in the surrounding countries. Agricultural production bears large external costs. There is substantial willingness to pay for an improved Baltic Sea environment among the public: this justifies environmentally sound farming practices. The contracting parties of HELCOM, including the Swedish government, have both environmental and economic incentives to use this window of opportunity before it closes. This thesis is the result of a collaboration between Mälardalen University and Stockholm Resilience Centre at Stockholm University. Both universities contributed with supervision and financial support at different stages of the research process. / I den här avhandlingen jämförs konventionellt jordbruk med ekologiskt kretsloppsjordbruk. Jämförelsen görs med avseende på miljöeffekter och socio-ekonomisk påverkan. Av miljöeffekterna är fokus på läckage av växtnäring men utsläpp av växthusgaser samt energianvändning studeras också. Till de socio-ekonomiska effekterna räknas effekter på produktionsvolym samt kostnader och nyttor på såväl samhälls- som företags- och hushållsnivå. Jämförelsen görs på regional (Östersjöområdet), nationell (Sverige) och lokal (Järna/Södertälje kommun) nivå. På regional nivå är den stora utmaningen att omvandla jordbruksproduktionen i miljövänlig riktning och att minska närsaltsbelastningen samtidigt som produktionen hålls uppe. På nationell nivå är en utmaning att ändra produktionssammansättningen mot mer grönsaker och mindre kött samt att minska den geografiska uppdelningen av djurhållning och spannmål. På lokal nivå är utmaningen att uppnå en hållbar landsbygdsutveckling ur miljömässigt såväl som ekonomiskt och socialt perspektiv. Resultat: på regional nivå beräknas miljöpåverkan och påverkan på livsmedelsproduktion i tre olika scenarier. Enligt ett scenario omvandlar Polen och de baltiska staterna sina jordbrukssektorer efter samma struktur och resursanvändning som ett genomsnittligt svenskt jordbruk. Det resulterar i att överskottet av kväve och fosfor i jordbruket ökar med 58% respektive 18% samtidigt som livsmedelsproduktionen ökar. Två andra scenarier där jordbruket i hela Östersjöregionen ställer om till ekologiskt kretsloppsjordbruk resulterar i reduktion av kväveöverskottet från jordbruket med 47-61% samt att fosforöverskottet elimineras. I de här scenarierna skulle livsmedelsproduktionen minska eller vara i princip oförändrad beroende på vilken strategi som väljs. På nationell nivå jämförs miljöpåverkan av olika produktionsmetoder, av transporter samt av olika matkassar. En hushållsstudie genomfördes i en grupp miljömedvetna konsumenter för att konstruera en alternativ matkasse. Matkassen innehöll en stor andel grönsaker, en liten andel kött och mycket lokalt och ekologiskt producerad mat jämfört med en genomsnittlig svensk matkasse. Den var även 24% dyrare i inköp. Det visade sig att miljöbelastningen påverkades väl så mycket av matkassens innehåll som av produktionsmetod. Lokal produktion och förädling var inte lika betydelsefullt. På lokal nivå studerades ett nätverk av entreprenörer engagerade i produktion, förädling och distribution av ekologiska livsmedel. Semistrukturerade intervjuer användes för att studera nätverket. Ett resilient, självorganiserande nätverk karaktäriserat av ekonomisk stabilitet och socialt kapital observerades. En hög andel av lokalt producerad och konsumerad mat samt ett väl fungerande samarbete i nätverket av entreprenörer och mellan entreprenörer, konsumenter och kommunen bidrog till ekonomisk hållbarhet. EU:s utvidgning innebär en möjlighet till förändrad förvaltning av Östersjön och jordbrukssektorn. En omställning i stor skala till ekologiskt kretsloppsjordbruk skulle leda till miljöförbättringar. En hållbar förvaltning av Östersjön, något som överenskommits inom ramen för HELCOM, kan inte uppnås samtidigt som jordbruksproduktionen maximeras i länderna runt Östersjön. Jordbruket orsakar betydande externa kostnader. Betalningsviljan för en förbättrad Östersjömiljö är stor vilket motiverar investeringar i ett miljövänligare, hållbart jordbruk. Medlemmarna i HELCOM, däribland Sveriges regering, har såväl ekonomiska som miljömässiga incitament att utnyttja möjligheten som Polens och de baltiska staternas EU-inträde innebär. Den här avhandlingen är ett samarbetsprojekt mellan Mälardalens högskola och Stockholm Resilience Centre vid Stockholms universitet. Båda lärosätena bidrog med handledning och finansiering under avhandlingsprojeket.

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