Fakultet for biovitenskap, fiskeri og økonomi: Recent submissions
Now showing items 1261-1280 of 5180
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Effect of glacial drainage water on the CO2 system and ocean acidification state in an Arctic tidewater-glacier fjord during two contrasting years
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-02-03)In order to investigate the effect of glacial water on the CO<sub>2</sub> system in the fjord, we studied the variability of the total alkalinity (A<sub>T</sub>), total dissolved inorganic carbon (C<sub>T</sub>), dissolved inorganic nutrients, oxygen isotopic ratio (δ<sup>18</sup>O), and freshwater fractions from the glacier front to the outer Tempelfjorden on Spitsbergen in winter 2012 (January, ... -
Distribution, density and abundance of Antarctic ice seals off Queen Maud Land and the eastern Weddell Sea
(Journal article; Tidsskriftartikkel; Peer reviewed, 2016-09-09)The Antarctic Pack Ice Seal (APIS) Program was initiated in 1994 to estimate the abundance of four species of Antarctic phocids: the crabeater seal Lobodon carcinophaga, Weddell seal Leptonychotes weddellii, Ross seal Ommatophoca rossii and leopard seal Hydrurga leptonyx and to identify ecological relationships and habitat use patterns. The Atlantic sector of the Southern Ocean (the eastern ... -
Determinants of parasite distribution in Arctic charr populations: catchment structure versus dispersal potential
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-06-18)Parasite distribution patterns in lotic catchments are driven by the combined influences of unidirectional water flow and the mobility of the most mobile host. However, the importance of such drivers in catchments dominated by lentic habitats are poorly understood. We examined parasite populations of Arctic charr Salvelinus alpinus from a series of linear-connected lakes in northern Norway to ... -
High Arctic Mytilus spp.: occurrence, distribution and history of dispersal
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-10-16)Many marine species are known to change their distribution in response to changing climatic conditions. One such example is the blue mussel Mytilus spp., spreading northward coincident with an increase in ocean temperatures. On Svalbard, the frst living specimens of Mytilus spp. were discovered in 2004. Here we present an analysis of the current distribution of Mytilus spp. on Svalbard, with a ... -
Freshwater and its role in the Arctic Marine System: Sources, disposition, storage, export, and physical and biogeochemical consequences in the Arctic and global oceans
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-10-11)The Arctic Ocean is a fundamental node in the global hydrological cycle and the ocean’s thermohaline circulation. We here assess the system’s key functions and processes: (1) the delivery of fresh and low-salinity waters to the Arctic Ocean by river inflow, net precipitation, distillation during the freeze/thaw cycle, and Pacific Ocean inflows; (2) the disposition (e.g., sources, pathways, and ... -
Fishes in a changing world: learning from the past to promote sustainability of fish populations
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-03-14)Populations of fishes provide valuable services for billions of people, but face diverse and interacting threats that jeopardize their sustainability. Human population growth and intensifying resource use for food, water, energy and goods are compromising fish populations through a variety of mechanisms, including overfishing, habitat degradation and declines in water quality. The important ... -
Evolution of seasonal adaptations in voles - a physiological and genetic approach
(Doctoral thesis; Doktorgradsavhandling, 2022-05-06)<p>This thesis addressed phenotypic and genetic variation in seasonal time keeping mechanisms of the tundra vole (<i>Microtus oeconomus</i>) and the common vole (<i>Microtus arvalis</i>). Voles (<i>Microtus</i>) are short-lived, non-hibernating and seasonally breeding rodents. The genus has rapidly evolved (< 2 million years) into one of the most speciose mammalian genera (Sitnikova et al. 2007; ... -
Freeze–thaw cycles have minimal effect on the mineralisation of low molecular weight, dissolved organic carbon in Arctic soils
(Journal article; Tidsskriftartikkel; Peer reviewed, 2016-03-11)Warmer winters in Arctic regions may melt insulating snow cover and subject soils to more freeze– thaw cycles. The effect of freeze–thaw cycles on the microbial use of low molecular weight, dissolved organic carbon (LMW-DOC) is poorly understood. In this study, soils from the Arctic heath tundra, Arctic meadow tundra and a temperate grassland were frozen to -7.5 C and thawed once and three ... -
Why do the boreal forest ecosystems of Northwestern Europe differ from those of Western North America?
(Journal article; Tidsskriftartikkel; Peer reviewed, 2016-07-20)The boreal forest is one of the largest terrestrial biomes on Earth. Conifers normally dominate the tree layer across the biome, but other aspects of ecosystem structure and dynamics vary geographically. The cause of the conspicuous differences in the understory vegetation and the herbivore–predator cycles between northwestern Europe and western North America presents an enigma. Ericaceous dwarf ... -
Genomic Changes Associated with the Evolutionary Transitions of Nostoc to a Plant Symbiont
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-03-15)Cyanobacteria belonging to the genus Nostoc comprise free-living strains and also facultative plant symbionts. Symbiotic strains can enter into symbiosis with taxonomically diverse range of host plants. Little is known about genomic changes associated with evolutionary transition of Nostoc from free-living to plant symbiont. Here, we compared the genomes derived from 11 symbiotic Nostoc strains ... -
Getting ready for host invasion: Elevated expression and action of xyloglucan endotransglucosylases/hydrolases in developing haustoria of the holoparasitic angiosperm Cuscuta
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-11-11)Changes in cell walls have been previously observed in the mature infection organ, or haustorium, of the parasitic angiosperm Cuscuta, but are not equally well charted in young haustoria. In this study, we focused on the molecular processes in the early stages of developing haustoria; that is, before the parasite engages in a physiological contact with its host. We describe first the identification ... -
Effect of dietary components on the gut microbiota of aquatic animals. A never-ending story?
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-11-07)It is well known that healthy gut microbiota is essential to promote host health and well-being. The intestinal microbiota of endothermic animals as well as fish are classified as autochthonous or indigenous, when they are able to colonize the host’s epithelial surface or are associated with the microvilli, or as allochthonous or transient (associated with digesta or are present in the lumen). ... -
RAT-RS: a reporting standard for improving the documentation of data use in agent-based modelling
(Journal article; Tidsskriftartikkel; Peer reviewed, 2022-03-30)This article describes and justifies a reporting standard to improve data use documentation in Agent-Based Modelling. Following the development of reporting standards for models themselves, empirical modelling has now developed to the point where these standards need to take equally effective account of data use (which previously has tended to be an afterthought to model description). It is ... -
The salmon louse genome may be much larger than sequencing suggests.
(Journal article; Tidsskriftartikkel; Peer reviewed, 2022-04-22)The genome size of organisms impacts their evolution and biology and is often assumed to be characteristic of a species. Here we present the frst published estimates of genome size of the ecologically and economically important ectoparasite, Lepeophtheirus salmonis (Copepoda, Caligidae). Four independent L. salmonis genome assemblies of the North Atlantic subspecies Lepeophtheirus salmonis ... -
The impact of fisheries management on fishers' health and safety: A case study from Norway
(Journal article; Tidsskriftartikkel; Peer reviewed, 2022-04-18)Since the late 1980s, Norwegian fishers have been subjected to a cohesive regulatory regime aimed at sustainable resource management. Despite high occupational injury rates and exposure to several factors that may influence health negatively, regulation of occupational health and safety (OHS) came late in fishing compared with other industries. Fisheries management and safety management are not ... -
Personal and socioeconomic factors affecting perceived knowledge of farmed fish
(Journal article; Tidsskriftartikkel; Peer reviewed, 2022-04-18)The global decline in wild fish has given impetus to the rapid growth of seafood produced by aquaculture, as well as of farmed fish (FF). Although product knowledge is directly linked to fish consumption, continuous asymmetric information leads to consumer ambiguity and confusion regarding their knowledge of farmed fish. However, ambiguity tolerance (AT) and confusion avoidance (CA) as personal ... -
Aktuelle sykdomsutbrudd og diagnoser
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020)Aktuelle diagnoser, «nye» sykdommer og spesielle tilfeller har i mange år blitt presentert under vignetten «Aktuelle sykdomsutbrudd og diagnoser fra Veterinærinstituttet, Mattilsynet og NMBU Veterinærhøgskolen». Redaksjonen er av den oppfatning at dette er nyttig og lett tilgjengelig informasjon som bidrar til å opprettholde medlemmenes kunnskap om utviklingen innen diagnostikk og overvåkning av ... -
Five decades of terrestrial and freshwater research at Ny-Ålesund, Svalbard
(Journal article; Tidsskriftartikkel; Peer reviewed, 2022-04-19)For more than five decades, research has been conducted at Ny-Ålesund, in Svalbard, Norway, to understand the structure and functioning of High-Arctic ecosystems and the profound impacts on them of environmental change. Terrestrial, freshwater, glacial and marine ecosystems are accessible year-round from Ny-Ålesund, providing unique opportunities for interdisciplinary observational and experimental ... -
Tangled up in prices going up and down: price determination in selected agri-food markets
(Doctoral thesis; Doktorgradsavhandling, 2022-05-02)<p>The dissertation includes four papers altogether. Three papers examine mechanisms for price transmission between markets. Among them, one deals with price transmission along the supply chain, and the other two deal with price transmission across spatially distinct markets. The fourth paper measures the effects of demand shifts on the market price equilibrium. <p>Paper 1 investigates price ... -
High-throughput DNA sequencing of the moose rumen from different geographical locations reveals a core ruminal methanogenic archaeal diversity and a differential ciliate protozoal diversity
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-10-13)Moose rumen samples from Vermont, Alaska and Norway were investigated for methanogenic archaeal and protozoal density using real-time PCR, and diversity using high-throughput sequencing of the 16S and 18S rRNA genes. Vermont moose showed the highest protozoal and methanogen densities. Alaskan samples had the highest percentages of Methanobrevibacter smithii, followed by the Norwegian samples. One ...