Now showing items 61-70 of 162
Bioprospecting of Arctic marine organisms Employing bioassay-, chemistry-, and metabolomics-guided isolation
(Doctoral thesis; Doktorgradsavhandling, 2015-09-25)
The marine environment inhabits a large diversity of organisms that produce natural products as a strategy for survival. Many marine natural products are found to display different bioactivities and some of them have reached the market as drugs or dietary supplements. Comprehending the great potential of bioactive marine natural products motivates for the continuing bioprospecting of organisms from ...
Decadal changes in distribution, abundance and feeding ecology of baleen whales in Icelandic and adjacent waters. A consequence of climate change?
(Doctoral thesis; Doktorgradsavhandling, 2016-01-15)
Five species of baleen whales are regularly encountered at their feeding grounds in Icelandic waters during summer. Systematic monitoring of distribution and abundance of cetaceans in Icelandic and adjacent waters was initiated in 1987 as a part of the North Atlantic Sightings Surveys (NASS). In this thesis, the objecive is to summarize the results of these surveys in relation to changes in the ...
Reproductive behaviour and sex trait allocations in an external fertilizer – the Charr (Salvelinus alpinus)
(Doctoral thesis; Doktorgradsavhandling, 2010-05-12)
This thesis illuminates several aspects of mate choice and sexual selection in a species with external fertilization and no parental care. At a general level we have contributed to the basic framework within evolutionary biology and ecology and at a more specific level, as the proximate mechanisms controlling the associations between immune response, parasite intensities and traits indicative of ...
Niche construction across climate gradients: the case of Empetrum nigrum in tundra plant communities
(Doctoral thesis; Doktorgradsavhandling, 2018-06-08)
Here we studied at relevant spatial and temporal scales, how the evergreen dwarf shrub Empetrum nigrum, through its niche constructor ability, affects tundra plant communities along climatic gradients. Empetrum is a common dwarf shrub which is particularly abundant in many tundra ecosystems. As a niche constructor is has strong influence on many ecosystem processes and its direct effects can last ...
Endogenous sharing of knowledge
(Doctoral thesis; Doktorgradsavhandling, 2017-12-13)
This thesis investigates the willingness of firms to cooperate on Research and Development (R&D). I present three papers concerning incentives to share/exchange knowledge created by the firms’ own R&D. It is my hope that this thesis can give some clues of how sharing and exchange of knowledge can contribute to an already large literature on Research and Development.
Planktonic food webs in the Arctic Ocean : structure and function in contrasting seasons and physical settings across Fram Strait
(Doctoral thesis; Doktorgradsavhandling, 2011-12-08)
This thesis investigates the structure and function of planktonic food webs at two sites between Greenland and the Svalbard Archipelago, covering a coastal ecosystem influenced by Atlantic water masses (Kongsfjorden, 78º N) and a more oceanic system off the East Greenlandic shelf, influenced by the outflow of Arctic water and sea ice from the Arctic Ocean (northwest Fram Strait, 75 - 80º N). In ...
The governance of Sami reindeer husbandry in Norway : institutional challenges of co-management
(Doctoral thesis; Doktorgradsavhandling, 2012-06-15)
Denne avhandlingen er basert på en kvalitativ studie fra forvaltningen av reindriften i Norge. Målet med forvaltningen av reindriften i Norge er å oppnå en økologisk, økonomisk, og kulturell bærekraftig reindrift. Disse målene har blitt forsøkt oppnådd gjennom et governance system fordi myndighetene har erkjent at det å inkludere ressursbrukere i forvaltningsmessige beslutningsprosesser skaper en ...
Primary production and the relevance of small autotrophic and heterotrophic cells in marine arctic ecosystems
(Doctoral thesis; Doktorgradsavhandling, 2011-12-02)
The Arctic is one of the least studied regions in the world and large changes in marine ecosystem dynamic are expected here because of the increasing air and ocean temperature. The central Arctic Ocean has for a long time been considered as a very low productive ecosystem, but recent estimates of primary production gives relatively high values. The shelves surrounding the Arctic Ocean are highly ...
Acute and long-term effects from petroleum discharges on temperate and Arctic Calanus species
(Doctoral thesis; Doktorgradsavhandling, 2011-11-11)
Summary Petroleum exploitation is emerging in the Arctic. In the Norwegian Arctic the southern Barents Sea is opened for development of oil and gas fields. This same area holds some of the world's largest and well managed commercial fish stocks such as Herring (Clupea harengus), Capelin (Mallotus villosus), Haddock (Melanogrammus aeglefinus), Atlantic Cod (Gadus morhua). For the interest of the ...
Marine Ecosystem Governance in the Making : Planning for petroleum activity in the Barents Sea-Lofoten area
(Doctoral thesis; Doktorgradsavhandling, 2011-03-25)
Expanding petroleum activity in the Barents Sea-Lofoten area has worked as a catalyst for the development and introduction of the first integrated, ecosystem-based management plan in Norway. This plan sets the framework, in particular, for further petroleum activities. Building on Science and Technology Studies (STS) this thesis provides an analysis of the practices and instrumentation of marine ...