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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.
241

En merkantilistisk början : Stockholms textila import 1720–1738 / A Mercantilistic Beginning : The Import of Textiles to Stockholm 1720-1738

Aldman, Lili-Annè January 2008 (has links)
The purpose of this thesis is to, from an institutional approach, study how the Stockholm importers within the textile sector adapted their foreign trade to the change in economic policy 1720 through 1738. The focus is to investigate to what extent the introduction of new laws, regulations etc. can be an explanation for what happened to Stockholm’s foreign trade, mainly imports, particularly textile imports during the period. It is mainly the economic policies that had been enacted during the Hornian government and their effects that have been studied. This is a period that has seldom been studied in other research. This thesis begins when the Russian raids were over. This was a year when the foreign trade still was relatively free and was untouched by the 17th century’s regulations. After 1721 the policies that would be introduced to increase Sweden's level of self-sufficiency and strengthen ties with the North Sea area had several components. Besides the economic policy, the main sources for the thesis are the city toll records. The trade policies in the shape of tolls and fees, import and consumption bans etc. and the commercial policies together became different kinds of political tools used for several purposes. The conclusion of this thesis is that the economic policies made the Stockholm importers adapt their trade to the change. The import bans and sumptuary laws had an effect. The economic policies gave rise to an increase in the import of textile raw materials. The rise in toll costs and import fees contributed to displacing the foreign trade towards other areas. The change in the economic policies was successful in the sense that it gave rise to new conditions for domestic production within the textile sector and forced Stockholm's importers to adapt their foreign trade.
242

Strategic and environmental uncertainty in social dilemmas

Lindahl, Therese January 2005 (has links)
Social dilemmas constitute a broad class of quandaries, including, for example, common pool resource (CPR) dilemmas and public good (PG) dilemmas. CPR's are characterized by non-excludability and rivalry and are often associated with overexploitation. Through similar arguments, the features non-excludability and non-rivalry give rise to under-provision of PG's. The prevalence and inefficiencies often associated with CPR's have given rise to an extensive literature and the role of resource uncertainty has not been ignored. Uncertainty combined with rivalry is often said to augment users' incentive to overexploit. However, underlying most of the theoretical research is an explicit or implicit assumption of symmetric information, or a symmetric lack of information. In reality, people generally have access to different sources of information and they may differ in their abilities to process information. In the first two papers of this thesis, the assumption of symmetry is relaxed and both papers demonstrate that from a welfare perspective, the distribution of uncertainty is also of importance. Many CPR's and PG's are natural, which can complicate the situation. In the traditional resource management literature, the exploited resource is often assumed to be properly characterized by some concave growth function. Today, there is extensive empirical evidence suggesting that many ecosystems have more complex, often non-linear dynamics. Management of such resources can be quite challenging as the non-linear dynamics can make the ecosystem flip between alternate stable states, and even marginal changes can cause radical transformations of such ecosystems. Most of the CPR models assume the shared resource to be of fixed size or to be able to generate a constant flow of services. In the third paper we aim at providing a more complete picture of the overexploitation of a common resource, by combining the institutional structure with complex ecological dynamics. We manage to raise questions and doubts about the standard assumptions. Another feature of convex-concave resources is that a state can become highly robust and sometimes an ecosystem change may even be irreversible. This is problematic if, for example, we wish to restore a degraded ecosystem. The aim of the fourth paper is to empirically analyze this question, by eliciting peoples' preferences through a hypothetical referendum on the issue. / Diss. Stockholm : Handelshögskolan, 2005
243

Evaluating the benefits and effectiveness of public policy

Sandström, F. Mikael January 1999 (has links)
The dissertation consists of four essays that treat different aspects or the evaluation of public policy. Two essays are applications of the travel cost method. In the first of these, recreational travel to the Swedish coast is studied to obtain estimates of the social benefits from reduced eutrophication of the sea. The second travel cost essay attempts at estimating how the probability that a woman will undergo mammographic screening for breast cancer is affected by the distance she has to travel to undergo such an examination. Using these estimated probabilities, the woman's valuation of the examination is obtained. The two other essays deal with automobile taxation. One essay analyzes how taxation and the Swedish eco-labeling system of automobiles have affected the sale of different car models. The last essay treats the effects of taxes and of scrappage premiums on the life length of cars. / Diss. Stockholm : Handelshögskolan, 1999
244

Predictive Modelling of Aquatic Ecosystems at Different Scales using Mass Balances and GIS

Gyllenhammar, Andreas January 2004 (has links)
This thesis presents models applicable for aquatic ecosystems. Geographical Information Systems (GIS) form an important part of the thesis. The dynamic mass balance models focus on nutrient fluxes, biotic/abiotic interactions and operate on different temporal and spatial scales (site, local, regional and international). The relevance and role of scale in mass balance modelling is a focal point of the thesis. A mesocosm experiment was used to construct a model to estimate the nutrient load of phosphorus and nitrogen from net cage fish farming (i.e., the site scale). The model was used to estimate what feeding conditions that are required for a sustainable aquaculture scenario, i.e., a zero nutrient load situation (a linkage between the site scale and the regional scale). A dynamic model was constructed for suspended particulate matter (SPM) and sedimentation in coastal areas (i.e., the local scale) with different morphometric characteristics and distances to the Sea. The results demonstrate that the conditions in the Sea (the regional and international scale) are of fundamental importance, also for the most enclosed coastal areas. A foodweb model for lakes was transformed and recalibrated for Baltic Sea conditions (i.e., the international scale). The model also includes a mass balance model for phosphorus and accounts for key environmental factors that regulate the presuppositions for production and biomasses of key functional groups of organisms. The potential use of the new model for setting fish quotas of cod was examined. For the intermittent (i.e., regional) scale, topographically complex areas can be difficult to define and model. Therefore, an attempt was made to construct a waterscape subbasin identification program (WASUBI). The method was tested for the Finnish Archipelago Sea and the Okavango Delta in Botswana. A comparison to results from a semi-random delineation method showed that more enclosed basins was created with the WASUBI method.
245

The importance of biodiversity for ecosystem processes in sediments : experimental examples from the Baltic Sea / Betydelsen av biologisk mångfald för ekosystemprocesser i sediment : experimentella exempel från Östersjön

Näslund, Johan January 2010 (has links)
Aquatic sediments are, by surface, the largest habitat on Earth. A wide diversity of organisms inhabit these sediments and by their actions they have a large influence on and also mediate many ecosystem processes. Several of these processes, such as decomposition and remineralisation of organic matter are important on a global scale and are essential to sustain life on Earth. The main aim of this thesis was to use an experimental ecosystem ecology approach in order to study some of these ecosystem processes in marine sediments and how they are linked to biodiversity. Paper I and II found that an increased species richness of sediment deposit feeders increases the processing of organic matter from phytoplankton settled on the sea-floor, and that species-rich communities have a more efficient resource utilization of deposited organic matter. The results in paper IV and V also suggest that there is a link between microbial diversity in sediments and the degradation of organic contaminants. Paper V also shows that antibiotic pollution is a potential threat to natural microbial diversity and microbially mediated ecosystem services. The introduction of invasive species to ecosystems is another major threat to biodiversity and was studied in Paper II and III, by investigating the ecology of Marenzelleria arctia, a polychaete worm recently introduced in the Baltic Sea. Paper II suggests that M. arctia mainly utilize food resources not used by native deposit feeders, thus potentially increasing the benthic production in the Baltic Sea by increasing resource use efficiency. Paper III, however, show that M. arctia is protected from predation by the native benthic invertebrate predators, due to its ability to burrow deep in the sediment, suggesting that predation on M. arctia by higher trophic levels is restricted, thereby limiting trophic transfer. In conclusion, this thesis gives some examples of the importance of marine biodiversity for the generation of a few key ecosystem processes, such as organic matter processing and the degradation of harmful contaminants. / At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Manuscript. Paper 3: Manuscript. Paper 4: In press.
246

Massbalansmodellering av fosfor i ett åländskt kustområde : en utredning om lokaliseringen av Lotsbroverkets utloppsledning

Eklund, Jenny January 2004 (has links)
This report is commissioned by the Water and Sewage Agency in The City of Mariehamn, Åland. The basic aim is to investigate positive or negative effects of a relocation of the sewage pipe from a wastewater treatment plant, Lotsbroverket. The environmental licence of Lotsbroverket is to be revised and The Environmental Appeal Board at Åland’s Government and Administrative Board has made demands that several possible locations in an outer water area should be examined. The present location of the sewage pipe is in Svibyviken, which has been classified as an “inner water area”. The objective of this work is to study to which extent the nutrient loading from Lotsbroverket influence the environmental conditions in Svibyviken, and to investigate the suitability of different locations of the wastewater pipe from Lotsbroverket. The way a coastal area looks, i.e., its morphometry, determines to a large extent its ecological characteristics. The investigated coastal area was digitalized from a nautical chart. The software used for this was Roots 3.3 and the GIS-tool ArcGIS 8.3. The localization of the coastal boundaries for the entire coastal area and for investigated sub-areas was determined according to the topographical bottleneck method, i.e., the boundary lines were drawn where the exposure of the coast to the open sea is minimized. A process-based dynamic mass-balance model for total phosphorous has been used in this study. Using this model, one can estimate and quantify the effects of different nutrient sources in coastal areas. All the fluxes of phosphorous to, from and within the defined areas were studied and ranked. Model simulations have shown how changes in any of the phosphorous fluxes influence the mean monthly concentrations of total phosphorous. The situation for total nitrogen was determined with a statistical/empirical regression model between phosphorous and nitrogen concentrations. To estimate the expected ecological effects from a change in the nutrient loading from Lotsbroverket, statistical/empirical correlations between modelled nutrient concentrations and ecological effect variables have been used. Standard effect variables for the study of eutrophication effects in coastal areas are, e.g., the chlorophyll concentration, Secchi depth and oxygen saturation in deep water. These variables have also been used in this study. It has been shown that (1) the nutrient concentrations of the Baltic Sea controls the concentration of nutrients in the studied areas to a very large extent, (2) that the nutrient fluxes from Lotsbroverket are small compared to the nutrient fluxes from the Baltic Sea and hence also of minor importance for the nutrient state of the receiving water system, (3) that the influence of the nutrient emissions from Lotsbroverket are most noticeable in the present inner recipient, Svibyviken, and (4) that the impact logically decreases with distance between the location of the sewage pipe and boundary line to the open sea. The overall conclusion is that no major improvement of the conditions in Svibyviken can be expected by a reduction or a relocation of the nutrient emissions from Lotsbroverket. / Detta examensarbete är ett uppdrag av VA-verket vid Mariehamns stad, Åland, med syfte att utreda effekter av en eventuell flyttning av avloppsreningsverket Lotsbroverkets utloppsledning. Inför en revidering av Lotsbroverkets miljötillstånd har Miljöprövningsnämnden vid Ålands landskapsregering ställt villkor på att tillståndshavaren skall utreda möjligheter till att avleda det renade avloppsvattnet till ett yttre vattenområde. Utloppsledningen mynnar i dagsläget i Svibyviken, vilken har klassificerats som ett inre vattenområde. Målsättningen med detta arbete är att belysa vilka ekologiska effekter näringsämnesutsläppet från Lotsbroverket har på primärrecipienten Svibyviken samt att undersöka några andra områdens lämplighet som mottagare av avloppsvattnet. Ett kustområdes utseende och form, det vill säga dess morfometri, avgör i stor utsträckning dess ekologiska förhållanden. För att få en god bild av det undersökta områdets morfometri digitaliserades området utifrån ett sjökort i digitaliseringsprogrammet Roots 3.3, varefter data bearbetades med GIS-verktyget ArcGIS 8.3. Avgränsning av kustområdet som helhet och av undersökta delområden gjordes enligt den topografiska flaskhalsmetoden, det vill säga så att kustens öppenhet mot utanförliggande hav eller vattenområde minimeras (Håkanson et al., 1984; Pilesjö et al., 1991). För arbetet har en processbaserad, dynamisk massbalansmodell för totalfosfor använts. Modellen har tagits fram för att eutrofieringseffekter i kustområden skall kunna studeras (Håkanson & Karlsson, 2001). Vid användandet av modellen kan effekter av olika näringsämneskällor uppskattas och kvantifieras. Samtliga totalfosforflöden till, från och inom olika avgränsade områden har studerats och rangordnats. Modellsimuleringar har visat hur förändringar i något av fosfortillflödena inverkar på recipientens månadsmedelkoncentration av totalfosfor. Situationen för kväve har undersökts med hjälp av en statistisk/empirisk regressionsmodell mellan fosfor- och kvävehalt. För att belysa de ekologiska effekter som kan förväntas efter en förändring av Lotsbroverkets fosfor- och kväveutsläpp har statistiska/empiriska kopplingar gjorts mellan näringsämneskoncentrationer och ekologiska effektvariabler. Bra effektvariabler vid undersökning av eutrofieringseffekter är exempelvis klorofyllhalt, siktdjup samt syrgashalt i bottenvattnet. Dessa variabler har också använts i detta arbete. Resultaten visar att (1) närsaltskoncentrationerna i de studerade områdena i hög grad styrs av den allmänna eutrofieringsnivån i Östersjön, (2) att utsläppet av näringsämnen från Lotsbroverket inte inverkar på recipientens näringsstatus i någon stor utsträckning, (3) att Lotsbroverkets påverkan är störst på nuvarande recipient, Svibyviken, (4) och att påverkan sedan successivt minskar ju längre ut mot öppna havet utloppsledningen lokaliseras. Slutsatsen av utredningen är att en reduktion av Lotsbroverkets utsläpp eller nylokalisering av utloppsledningen inte kan förväntas ge någon omfattande förbättring av tillståndet i Svibyviken.
247

IMO:s barlastkonventions konsekvenser för sjöfarten inom Östersjön / IMO’s Ballast Water Convention’s consequences for the shipping in the Baltic Sea

Pettersson, Daniel, Wallerstein, Fanny January 2012 (has links)
Arbetet behandlade vilka konsekvenser inom driften (ekonomiska kostnader och teknologi) som rederier kommer att drabbas av när IMO:s barlastkonvention träder i kraft då barlastvattnet måste renas innan inträde i Östersjön. Arbetets syfte var att få fram vilka konsekvenser det blir för rederier när IMO:s barlastkonvention träder i kraft. Resultatet skulle jämföra skillnaden mellan lag och rekommendation då Helsingforskonventionens rekommendationer baseras på IMO:s barlastkonventions krav. En kvalitativ metod valdes för att komma fram till resultatet, i form av en öppen intervjustudie, där fyra olika företag har intervjuats. Syftet med intervjuerna var att se ifall de följde Helsingforskonventionens rekommendationer och vilka konsekvenser det skulle innebära och skulle komma att krävas då Barlastkonventionen träder i kraft. Resultatet visade att kostnaderna kommer att bli omfattande vid installation samt att det kommer att krävas teknologiska åtgärder. Vidare visade undersökningen att inköpskostnaden endast utgör en liten del av fartygets investering och att barlastreningsanläggningar är tämligen underhållsfria. / The task discussed the consequences within the ship’s operation (economical costs and technology) companies will be affected with when IMO’s Ballast Water Convention enters into force and ballast water has to be treated before entrance to the Baltic Sea. The purpose with the task was to find out which consequences companies will be forced with when IMO’s Ballast Water Convention enters into force. The result compares the difference between law and recommendation because HELCOM’s recommendations are based on IMO’s Ballast Water Convention’s laws. A qualitative method has been used, such as an open interview form, where four different companies were interviewed. The purpose with the interviews was to see if the companies followed HELCOM’s recommendations and which consequences it would lead to and would be necessary when the Ballast Water Convention enters into force. The results showed that the costs would be extensive when installation takes place and it will require technical arrangements. The task also shows that the purchase cost only makes a small part of the vessel’s investment and ballast water treatment systems are almost totally maintenance-free.
248

Der Ostseerat - ein Beitrag zur Zivilisierung des internationalen Systems? / The Council of the Baltic Sea States: A Contribution to Civilizing the International System?

Prigge, Karla 17 August 2007 (has links)
No description available.
249

Mokslinių jūros tyrinėjimų atskirose jūros erdvėse reglamentavimas tarptautinėje jūrų ir Lietuvos Respublikos teisėje / Regulation of marine scientific research in separate maritime zones in international law of the sea and the Republic of Lithuania

Kubiliūtė, Aistė 03 June 2014 (has links)
Didėjantis tarptautinis bendradarbiavimas jūros aplinkos apsaugos srityje skatina intensyvesnį duomenų apie jūros aplinką rinkimą bei palankesnių sąlygų sudarymą MJT vykdymui. Šiame darbe siekta išanalizuoti MJT reguliavimą atskirose jūros erdvėse bei įvertinti Baltijos jūros šalių praktiką ir reglamentavimo trūkumus. Buvo išanalizuota 1982 m. Jungtinių Tautų jūrų teisės konvencija, ypač nuostatos susijusios su MJT, Helsinkio komisijos rekomendacijos, papildančios MJT teisinį režimą, apžvelgti Baltijos jūros valstybių, įskaitant Lietuvos, norminiai aktai. Darbe išanalizuotos MJT charakteristikos, Jūrų teisės konvencijoje naudojamos tyrimų sąvokos, pagrindiniai MJT reguliavimo principai, MJT praktika Baltijos jūros šalyse bei MJT ir jų teisinio reguliavimo svarba ES mastu. Tyrimų rezultatai parodė, kad Baltijos šalyse vis dėlto egzistuoja nemažai trūkumų MJT reglamentavime, ypač leidimų išdavimo procedūrose. / Growing international cooperation in marine protection field intensifies marine data collection and creation of more favourable conditions for marine scientific research activities. This scientific work analyses MSR regulation in separate maritime zones and assesses Baltic States practice and gaps in regulation. UNCLOS, especially provisions related to MSR, recommendation of HELCOM that complements legal regulation of MSR, Baltic States’ and Lithuanian national legal instruments were taken into account. Work presents MSR characteristics, research definitions which are used in Convention, the main MSR regulation principles, Baltic States practice regarding MSR and interest by EU on importance of legal regulation. Results of analysis have showed the existing gaps in MSR regulation in Baltic States, especially within permits issuing procedures.
250

Silicon cycling in the Baltic Sea : Trends and budget of dissolved silica / Kisels kretslopp i Östersjön : Trender och budget av löst kisel

Papush, Liana January 2011 (has links)
The dissolved silicon (DSi) has a crucial role for growth of a large group of primary producers – diatoms and, hence, impact on functioning of the aquatic food web. This thesis contributes to an increased understanding of the modifications of the DSi cycling in the Baltic Sea. The results provide new information about spatial and temporal changes in DSi concentrations and nutrient ratios for the period 1970-2001 as well as during the 20th century. For the period 1970-2001, the declining DSi trends were found at the majority of monitoring stations all over the Baltic Sea. This decrease is assumed to be mainly due to the ongoing eutrophication. It is supported by the increasing trends of inorganic nitrogen and phosphorus. The trends have implications for the nutrient ratios, DSi:DIN and DSi:DIP, which are important indicators of the state of an ecosystem. The long-term retrospective DSi budget has shown that the DSi concentrations before major hydrological alterations and eutrophication were about twice the present ones. This decrease is related to both eutrophication and anthropogenic perturbations in the catchment. The occurrence of DSi concentrations close to the potentially limiting levels has been also analysed. While DSi concentrations are still high in the northern regions of the Baltic, other areas may be at risk of developing Si limitation if the decrease in DSi concentrations persists. The results depict the Baltic Sea journey from being water body with DSi levels sufficient to support diatom production to one that may experience Si limitation and its adverse ecological consequences. / Löst kisel (DSi) har en viktig roll för tillväxten av en stor grupp av primärproducenter – kiselalger, och därmed även påverkar hela den akvatiska näringskedjan. Denna avhandling bidrar till en ökad förståelse av förändringarna i DSi kretsloppet i Östersjön. Resultaten tillhandahåller ny information om rumsliga och tidsmässiga förändringar i DSi koncentrationer såväl för perioden 1970-2001 som för hela 1900-talet. För perioden 1970-2001 återfanns minskade DSi koncentrationer på mätstationer över hela Östersjön. Minskningen antas främst bero på den pågående övergödningen. Detta antagande stöds av stigande halter av oorganiskt kväve och fosfor. Sammantaget har dessa trender en inverkan på ekosystemets tillstånd och näringsämnenas kvoter, DSi: DIN och DSi: DIP. Ur ett längre tidsperspektiv kan man se att innan övergödningen och de stora hydrologiska ombildningar i Östersjöområdet var DSi koncentrationerna ungefär dubbelt så höga som idag. Dagens förekomst av DSi koncentrationer som ligger nära de potentiellt begränsande nivåerna har också analyserats. DSi koncentrationerna är fortfarande höga i norra delar av Östersjön, men är i andra områden i riskzonen för att utveckla Si begränsning om minskningen av DSi koncentrationer fortsätter. Resultaten skildrar Östersjöns resa från att vara ett havsområde med DSi halter som är tillräckliga för att understödja kiselalgernas produktion till ett sådant som kan uppleva Si begränsning och dess negativa ekologiska konsekvenser.

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