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- Kadin, Martina
(författare)
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Man, murres and modern fisheries : A case study in the Baltic Sea
- 2012
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Overfishing and climate change put increasing pressure on marine systems, with effects on commercially targeted fish and top predators dependent on these resources. To achieve sustainable resource use, governance mechanisms need to incorporate knowledge about ecosystem dynamics. Another key for success is the perception among actors about the challenges oceans are facing. Seabirds have become well-known symbols of coasts and oceans and their struggles with the consequences of human actions provide an illustration of the need to properly govern marine resources. Seabirds can be useful indicators of states of marine systems, forming tools that can help informing ecosystem approaches to management. The thesis focuses on the piscivorous seabird the common murre Uria aalge in the Baltic Sea, investigating two different aspects of interactions between seabirds and fisheries. In paper I, the effects of food quality and quantity during the chick-rearing period were investigated. Food quality (sprat Sprattus sprattus weight-at-age), but not quantity (sprat abundance), was positively related to murre fledging success. The adjustments of parental effort in relation to quality and quantity showed the opposite pattern – no relationships between parental effort and sprat weight-at-age but a negative relationship between sprat abundance and the duration of foraging trips. Paper II uses a long-term ring recovery dataset to study murre bycatch in Baltic Sea fisheries. We found an increase in the proportion bycatch between 1972 and 2008, and a strong bimodal intraannual pattern in bycatches, with peaks in spring and autumn, similar in three investigated periods. Uncertain finding dates were common and could potentially affect conclusions about intraannual patterns. Reported bycatches were concentrated to waters around the Hel peninsula, Poland. In recent years, 2000-2008, an increase of reported bycatch could be observed in the southeastern parts of the Baltic Sea. The findings of this thesis can aid the selection and interpretation of indicators for ecosystem approaches to Baltic Sea fisheries management, and further be used to communicate the need for such approaches.
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| 2. |
- Widström, Torun
(författare)
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Enhanced Energy Efficiency and Preservation of Historic Buildings : Methods and Tools for Modeling
- 2012
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- As the environmental impacts of the energy usage of the world today becomes more and more evident, enhancement of energy performance of the already existing building stock becomes more urgent. Buildings belonging to the cultural heritage are often the ones that are most difficult to deal with in this context.The subject of this thesis is the use of building simulation of historic buildings. The task here is to identify and when necessary develop simulation tools and methods that are suitable for planning of retrofitting strategies in historic buildings, and to identify and analyze what demands such tools and methods would have to fulfill, in what contexts different simulation strategies are suitable, how the demands on the tools might be met and what results and how the results would facilitate the decision making process in the most optimal way. A powerful means to acquire such analyses is the use of whole-building simulation. In the case of historical buildings there are several aspects to take into consideration, determining the choice of simulation tool and method.This thesis includesInvestigation of the variability of the demands on simulation tools and methods that the historic buildings pose, and its implication on complexity of the simulation process, and suggestion of a complexity index tool.Investigation of the whole-building simulation process and how it complies with the demands identified, and how the exergy concept can be used, exemplified by a case study.Identification of a need for a tool and method for a large amount of cases not easily covered by abundantly available tools and methodsSuggestion of a tool and method to address these cases, and presentation of a case study where the suggested tool and method have been applied, with good agreement between the simulated and measured values.One important feature of the suggested tool is the Very Small Wall-part Method, that includes the assessment of especially damage prone points into the whole-building simulation model, otherwise unable to accommodate these points. Another is the damage risk assessment feature where a mould risk prediction tool is presented.
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