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Speciation reversal in sympatric eco-morphs of European whitefish (Coregonus lavaretus. L) – phenotypic and genomic consequences
(Doctoral thesis; Doktorgradsavhandling, 2016-09-20)
Anthropogenic activities, such as introduction of non-native species, is considered as one of the most significant causes for declining biodiversity, since such introduction may destabilise ecological barriers to gene flow between native populations. In the 1960s a salmonid fish, vendace, was introduced to the upper parts of Pasvik watercourse and during the early 1990s it invaded the entire ...
Marine microbial eukaryotes in Svalbard waters: Seasonality, community composition and diversity
(Doctoral thesis; Doktorgradsavhandling, 2016-10-18)
There is an increasing awareness of the importance and diversity of the microbial community in Arctic regions, but their role in the ecosystem is still largely unknown. Sampling was conducted in Svalbard waters with focus on the Adventfjorden-Isfjorden time series station (IsA, West Spitsbergen) that was sampled frequently from December 2011 to December 2012. The community composition of microbial ...
Seasonality of Meroplankton in Svalbard Waters
(Doctoral thesis; Doktorgradsavhandling, 2016-12-14)
The temporal dynamics of meroplankton, manly comprised of larvae of benthic invertebrates that only temporarily inhabit the pelagic environment, is poorly understood in Arctic environments. The main objective of this thesis was to increase our knowledge on meroplankton dynamics and their ecological role in the Arctic marine coastal ecosystem. Three different approaches including high-frequency field ...
The role of the invasive red king crab in the food web of a high-latitude fjord Studying macrobenthic communities and trophic control in Porsangerfjord, northern Norway
(Doctoral thesis; Doktorgradsavhandling, 2016-11-24)
Biological invasions are a major challenge facing coastal waters and increasingly threaten high-latitude environments. The red king crab is one of the world’s largest decapods and was introduced into the Barents Sea in the 1960s. It has since become a valuable fishery resource in Russian and
Norwegian waters. In the early 2000s, red king crabs entered Porsangerfjord, which now holds one of the ...
Invasive Heracleum in northern Europe: Introduction history and impact on native plant diversity
(Doctoral thesis; Doktorgradsavhandling, 2016-01-15)
Exotic invasive giant hogweeds are infamous in Europe for their ecological and economic damage; however, the magnitude of their impact on plant diversity has not yet been fully explored. In addition, uncertainties in their source and route of introduction impede management interventions. In such cases, molecular markers may bridge gaps between invasion history and management by providing insight ...
Calanus® Oil. Utilization, composition and digestion
(Doctoral thesis; Doktorgradsavhandling, 2016-07-03)
In the pelagic system, phytoplankton are the main producers of n-3 LC-PUFA and make up the foundation of the oceanic food web. Zooplankton, such as copepods and krill, are the most numerous primary consumers in the marine environment and have a central role in the energy transfer to higher trophic levels. The copepod Calanus finmarchicus is present in large amounts in the North Atlantic and has ...
At-sea behaviour of the world's northernmost harbour seal (Phoca vitulina) population in a changing Arctic
(Doctoral thesis; Doktorgradsavhandling, 2016-04-15)
The earth is experiencing warming at a rate that challenges the adaptive capacities of many animal species. Because marine mammals can integrate and reflect ecological variation across various spatial and temporal scales, they are prime sentinels of marine ecosystem change. This thesis explores movement patterns and foraging behaviour, and the ontogeny of these behaviours, in harbour seals (Phoca ...
Genetic complexity in the marine environment: Population genomics of saithe (Pollachius virens), Greenland halibut (Reinhardtius hippoglossoides), beaked and golden redfish (Sebastes mentella and S. norvegicus) in the North Atlantic
(Doctoral thesis; Doktorgradsavhandling, 2016-05-04)
In this work, I investigated genetic complexity in four commercially exploited species from the North Atlantic: saithe (Pollachius virens L.), Greenland halibut (Reinhardtius hippoglossoides), and beaked and golden redfish (Sebastes mentella and S. norvegicus). The results were used 1) to assess the consistency between current management units and units identified by results based on genetic data ...
Valuing Unfamiliar and Complex Ecosystem Services: The influence of survey mode, knowledge and dishonesty
(Doctoral thesis; Doktorgradsavhandling, 2016-08-15)
Increasing demand for valuation of ecosystem services has led stated preference methods to be applied to public goods that are increasingly complex and unfamiliar. Traditionally, stated preference surveys were conducted via mail or face-to-face interviews, but over the past two decades internet panels have been used to a larger extent. As we move away from traditional methods of survey administration ...
Interventions using digital tools to improve students’ engagement and learning outcomes in higher business education
(Doctoral thesis; Doktorgradsavhandling, 2016-11-25)
The purpose of the present study was to develop interventions using digital tools to improve student engagement and learning outcomes. The empirical context was an undergraduate finance course wherein digital learning and assessment interventions were important features of the course design.
When designing the interventions, the development activities were underpinned by pedagogical principles ...