Mastergradsoppgaver i biologi: Nye registreringer
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The effect of climate change on the fish community in Lille Rostavatn, northern Norway
(Master thesis; Mastergradsoppgave, 2020-12-21)Over the last 20 years there has been a large change in the fish community structure in Lille Rostavatn, northern Norway. The relative contribution of the cold-water adapted fish species, Arctic charr (<i>Salvelinus alpinus</i>) and burbot (<i>Lota lota</i>), has distinctly decreased whereas the more temperate-adapted fish species, grayling (<i>Thymallus thymallus</i>) and brown trout (<i>Salmo ... -
Hydrocarbon biodegradation potential in environmental bacterial metagenome
(Master thesis; Mastergradsoppgave, 2020-12-15)Hydrocarbon pollution in marine environments present an acute problem which is aggravated by cold temperatures. This is especially relevant in important environmental and economic northern regions such as the Barents Sea. The Barents Sea region has become the focus of oil industries from Russia and Norway, incrementing the risk of hydrocarbon pollution. Bioremediation is a cost-effective and ... -
Variation in epiphytic vegetation in spruce plantations and adjacent native birch forests in North Norway
(Master thesis; Mastergradsoppgave, 2007-05)Epiphytic vegetation can contribute to increased knowledge on how planting of spruce in areas where spruce does not occur naturally in the landscape can affect the environment. In the current study, 31 spruce plantations in Troms and Vesterålen in North Norway were investigated, with emphasis on species abundance of macrolichens on tree trunks and branches. The main assumption was that planting of ... -
Mercury in fish from a subarctic watercourse and its relation to trophic ecology
(Master thesis; Mastergradsoppgave, 2020-11-16)Mercury (Hg) contamination in aquatic ecosystems is a serious concern because it can bioaccumulate and biomagnify to harmful concentrations within a food web and consequently end up in humans that eat polluted fish. The Pasvik watercourse, located in the border area between Norway, Finland and Russia, is strongly affected by the emissions of heavy metals from nearby Russian metallurgic smelters. In ... -
Foraging behaviour of humpback whales (Megaptera novaeangliae): Automatic detection of feeding lunges from two-dimensional data
(Master thesis; Mastergradsoppgave, 2020-09-10)Rorqual whales (Family Balaenopteridae) forage almost exclusively by performing so-called feeding lunges. It is difficult to study rorqual foraging behaviour through direct observation because most of the lunges are carried out deep in the water column. The introduction of high-resolution digital tags recording three-dimensional (3D) acceleration has allowed for the collection of complex movement ... -
The influence of herring (Clupea harengus) biomass and distribution on killer whale (Orcinus orca) movements on the Norwegian shelf
(Master thesis; Mastergradsoppgave, 2020-06-01)Killer whales (Orcinus orca) have a cosmopolitan distribution with a broad diet ranging from fish to marine mammals. Regional populations show local prey specialization and their movements are tightly linked to those of their prey. Norwegian killer whales are known to feed extensively on Norwegian spring spawning (NSS) herring (Clupea harengus). Over the last decade, killer whales have begun to ... -
Overexpression analysis of bilberry (Vaccinium myrtillus L.) R2R3-MYB transcription factors
(Master thesis; Mastergradsoppgave, 2020-06-15)Bilberry (Vaccinium myrtillus L.) is a dwarf shrub and its berries are rich source of nutrients, fibers and vitamins. Bilberry consumption has been shown to positively correlated with improvement of human health. Anthocyanins and proanthocyanidins (PAs) are important secondary metabolites that are synthetized in plants via flavonoid biosynthesis pathway. PAs also have anti-cancer, anti-inflammatory ... -
Change in sugar levels and related gene expression during bilberry fruit development and ripening
(Master thesis; Mastergradsoppgave, 2020-06-15)Vaccinium myrtillus L., commonly known as European blueberry or bilberry, has been used as food and medicine since ancient times. Bilberries are highly valued in European and Asian markets. Sugar accumulation is responsible for the sweet taste of fruit, which is one of the main determinants of fruit quality. However, sugar metabolism in bilberry has not been studied before. This study was aimed to ... -
Epibenthic and Demersal Fish Community Structure and the Effects of Environmental Conditions in the Sub-Arctic Fjords Vengsøyfjorden and Kaldfjorden
(Master thesis; Mastergradsoppgave, 2020-06-01)Epifauna are organisms that live on, or close to, the sediment surface and commonly consist of taxa such as sea anemones, sea/brittle stars, and crustaceans. These communities have an important role in redistributing and remineralizing marine organic matter, and as prey for commercially important shellfish and fish. The structure of epibenthic communities can be important indicators of anthropogenic ... -
Sympagic-pelagic coupling and vertical export in two seasonally ice-covered fjords. Study of the physical and biological drivers in the sub-Arctic Ramfjorden (Norwegian mainland) and the Arctic Van Mijenfjorden (Svalbard archipelago) during early spring bloom.
(Master thesis; Mastergradsoppgave, 2020-06-01)Fjords are important high latitudes ecosystems, many have beside planctonic ones, a unique ecosystem associated with seasonal ice cover. During the development of the spring season conditions, two major type of primary producers contribute highly to the biomass production: sea-ice algae inhabiting brine channels and bottom surface of the ice (sympagic algae) and phytoplankton, living in the water ... -
Hungry during migration? Humpback whale movement from the Barents Sea to a feeding stopover in northern Norway revealed by photo-ID analysis
(Master thesis; Mastergradsoppgave, 2020-06-01)In the last nine winters, a humpback whale feeding aggregation has been observed in the nearshore waters and fjords of northern Norway. This seasonal humpback whale occurrence is presumably driven by a shift in the overwintering distribution of Norwegian spring spawning (NSS) herring into these coastal areas. Eastern North Atlantic humpback whales feed during summer in relative remote regions in ... -
Stability of space use in Svalbard coastal female polar bears: Intra-individual variability and influence of kinship
(Master thesis; Mastergradsoppgave, 2020-06-01)Philopatry influences the distribution of animals and can lead to the formation of kinship-based population structures when relatedness among individuals is tightly linked to their proximity. Two different polar bear ecotypes exist in the Barents Sea sub-population: “coastal” bears and “offshore” bears. Coastal bears remain year-round within the Svalbard archipelago whereas offshore bears follow the ... -
Homesick plants - a study on Plant-soil feedback in home and foreign soil following a latitudinal sampling gradient from Morocco to Svalbard
(Master thesis; Mastergradsoppgave, 2020-06-01)Plant-soil feedbacks receive increasing attention as impactors of plant performance and drivers of plant community composition. How plant-soil feedbacks act in introduction events regarding both native and foreign species is a topic requiring more research. In this aspect, two particular theories are of interest, Home-field advantage, and Enemy-release. The former predicts that plants perform best ... -
Can aquaculture impact the surrounding biodiversity? A metabarcoding assessment
(Master thesis; Mastergradsoppgave, 2020-06-01)World’s population growth and rise in food consumption per capita have led to increased food demand and overexploitation of natural resources in recent decades. Such increase has threatened the global feeding schemes to maintain a balance between food supply and demand. Although “The Blue Revolution” promised to fill such gap and simultaneously alleviate the overexploitation of the oceans, deterioration ... -
Do the predators of Yamal have a learning effect of artificial nests?
(Master thesis; Mastergradsoppgave, 2020-06-01)Many artificial nest studies that goes over several years place the nests in the same location each placement. Over the years there is a chance that the predators learn where the nests are placed and that can give skewed results. The goal of my study is to see if the predators learn where the nests are located. This was done over three study sites on the Yamal peninsula. In two of the study sites ... -
eDNA metabarcoding of amoebic gill disease (AGD) pathogens exposes potential vectors and reservoirs
(Master thesis; Mastergradsoppgave, 2020-05-31)Aquaculture worldwide is under constant scrutiny and financial pressure to maintain fish health, while providing an essential food source to a growing populace. To assist in monitoring mariculture sites and preventing harmful diseases, we tested a recently proposed method of trace pathogen detection using eDNA metabarcoding. The target pathogen, Paramoeba perurans, is the etiological agent of AGD, ... -
The Demersal Fish Community on the West Spitsbergen Shelf. Biodiversity, species composition, distribution and temporal changes in relation to climate.
(Master thesis; Mastergradsoppgave, 2020-05-29)This thesis explores a historical time series of trawl stations on the West Spitsbergen Shelf (WSS), aiming to understand the spatial and temporal variability of the demersal fish communities in the region. Abundance data of 42 fish species are used to investigate the species composition, richness, and diversity across six different areas under different environmetal influence. The results indicate ... -
Interannual variability (2014-2019) of hydrography, fluorescence and nutrient distribution in Vestfjorden, Lofoten
(Master thesis; Mastergradsoppgave, 2020-06-01)Vestfjorden is an area of great ecological relevance since it is one of the main spawning areas of North East Atlantic cod. The survival rate of the cod larvae depends greatly on the abundance of zooplankton, which in turn depends on phytoplankton. Due to the extreme seasonality of high latitude fjords with a short productive season, understanding the phytoplankton distribution in spring is crucial. ... -
Dietary vs. light stimulated smoltification: effects on smolt development and appetite regulation in pre- and post- smolts
(Master thesis; Mastergradsoppgave, 2020-05-22)The transfer of smolt from freshwater (FW) to seawater (SW) is a critical stage in the farming of Atlantic salmon (Salmo salar) with mortalities of up to 15 % after transfer. One of the reasons for this loss is suboptimal smolt quality. It is therefore important to ensure that the fish are fully SW adapted before transfer to SW. Traditionally, smoltification is stimulated by exposing the fish to a ... -
Analysis of xyloglucan-modifying genes and enzymes at graft-junctions of tomato plants
(Master thesis; Mastergradsoppgave, 2020-05-16)Grafting is a widely used technique for propagation of plants in both agriculture and horticulture worldwide and involves combining two or more plants into one chimeric plant, ultimately with a shared vascular system. Benefits of grafting such as pathogen resistance, increase in fruit yield and abiotic stress tolerance have long been known, but the biological mechanisms of how plants graft are still ...