Publikasjoner
NIBIOs ansatte publiserer flere hundre vitenskapelige artikler og forskningsrapporter hvert år. Her finner du referanser og lenker til publikasjoner og andre forsknings- og formidlingsaktiviteter. Samlingen oppdateres løpende med både nytt og historisk materiale. For mer informasjon om NIBIOs publikasjoner, besøk NIBIOs bibliotek.
2017
Sammendrag
Detailed descriptions of individual vegetation types shown on vegetation maps can improve the ways in which the composition and spatial structure within the types are understood. The authors therefore examined dwarf shrub heath, a vegetation type covering large areas and found in many parts of the Norwegian mountains. They used data from point samples obtained in a wall-to-wall area frame survey. The point sampling method provided data that gave a good understanding of the composition and structure of the vegetation type, but also revealed a difference between variation within the vegetation type itself (intra-class variation) and variation resulting from the inclusion of other types of vegetation inside the map polygons (landscape variation). Intra-class variation reflected differences in the botanical composition of the vegetation type itself, whereas landscape variation represented differences in the land-cover composition of the broader landscape in which the vegetation type was found. Both types of variation were related to environmental gradients. The authors conclude that integrated point sampling method is an efficient way to achieve increased understanding of the content of a vegetation map and can be implemented as a supporting activity during a survey.
Sammendrag
The composition of plant secondary metabolites (PSMs) extensively impacts ecosystem functioning. It is vital that we understand temporal patterns in the plants’ allocation of resources to PSMs, particularly those influenced by human activity. Existing data are insufficient in the long-term perspective of perennial plants (age or ontogeny). We analysed phenolic concentrations in foliage from birch (Betula pubescens Ehr.) considered to be undamaged and growing on 5, 10 and 15 years old clear-cuts in two boreal forest landscapes in Norway, sampled at the peak of the growing season. In sum, low molecular weight phenolic concentrations decreased with age. Apart from one apigenin glycoside, the low molecular weight phenolics co-varied similarly at all ages, suggesting a lack of temporal compound-specific prioritisation of this group. In contrast, the concentration of MeOH-soluble condensed tannins increased with age. The compositional shift fits well with several hypotheses that may provide proximate explanations for age patterns in PSM allocations, including both resource constraints and external pressures. Regardless of these explanations, our study adds an important perennial perspective (plant age) to temporal PSM patterns already well-known in boreal plant phenology (foliage age).
Forfattere
Jasmina Vejnovic Branko Djuric Peder Lombnæs Bal Ram SinghSammendrag
Deficient trace elements concentration in soils, forages, and animals have been reported in several areas of Balkan region. Main challenge in overcoming low productivity of forage and animal production in this region is the lack of data on the nutritional status of the pastures and soils. This study examined the nutrient and pseudo total concentration of trace elements in soil and herbage plants, and the potential deficiency or excess with regards to crop and livestock production. Soil and plant samples from 100 sampling points were collected in the mountainous grasslands of Manjača (between longitudes 16°56′ and 17°8′ east; and latitudes 44°33′ and 44° 42′ north) and Vlašić (between longitudes 17°14′ and 17°29′ east; and latitudes 44°25′ and 44°37′ north). Soil samples were analysed for soil texture, pseudo total concentration (5 ml HNO3) of trace elements (TE), pH, soil organic carbon (SOC), while plant samples were analysed for TE. The soil pH varied from strongly acidic to moderately alkaline. The concentration of SOC varied from 0.5% to 12.3%. Most of the soil samples were finer-textured soils high in silt content. The average concentrations of Na, P, Zn, Se, Cu, Co, and B were low in both soil and herbage plants. Plant K, Ca, Mg, Mo, and Mn concentrations were sufficiently high to meet the requirements of grazing animals, while Fe concentrations was elevated in certain areas. High levels of Mo were found in both soil and plants. The results suggest that imbalances observed in natural pastures of Manjača and Vlašić area, caused by low soil TE concentration and other soil and plant properties, could contribute to poor animal nutrition.
Forfattere
Aytac ErdemirSammendrag
Det er ikke registrert sammendrag
Sammendrag
Forests and wooded land cover 39% of the land area of Norway, with two conifer species, Picea abies and Pinus sylvestris, dominating the forest area. Twenty-five of 35 native forest tree species have their northern limit in this country. The genetic resources of 18 species are considered to be vulnerable or threatened either at a local or national level. Genetic information is available for 13 of the native species, with Picea abies being the species that has been most thoroughly characterised. The National Programme for Forest Genetic Resources is administered by the Norwegian Genetic Resource Centre. This programme covers four major areas: generating knowledge and monitoring processes influencing genetic resources; in situ and ex situ conservation activities; sustainable use and development of forest genetic resources; and networking, coordination and dissemination of knowledge. In situ conservation of genetic resources of forest tree species is carried out in nature reserves. Twenty-three gene conservation units, covering ten species, have been established in such reserves. Ex situ conservation of forest genetic resources is achieved through collections in arboreta and botanical gardens and in the long-term field plantations of research and breeding programmes. In addition, seed samples of selected forest tree species are stored at Svalbard Global Seed Vault. Forests in Norway are regenerated both by natural and artificial means. A revised tree breeding strategy, with emphasis on Picea abies, has been developed to improve climatic adaptation, growth and quality, without decreasing the genetic diversity in future forests or the potential for adaptation to future climatic conditions.
Forfattere
Andreas C. Drichoutis Achilleas Vassilopoulos Jayson L. Lusk Rodolfo M. Jr. NaygaSammendrag
High-profile cases of exploitative labour practices have increased concerns over agricultural working conditions. However, it is unclear to what extent the public is willing to trade-off fair working conditions for higher prices. We implement a large-scale survey in Greece to uncover consumer preferences for a food labelling system that certifies fair working conditions for the workers employed in agricultural production. With our most conservative estimates, we find that consumers are willing to pay an average premium of 53 cents of a Euro per 500 g, 95 per cent CI [43.9, 62.3], for strawberries with fair labour certification. This result suggests that consumers do value the better treatment of workers in the agricultural sector. It also suggests that there is a current market failure, created by the asymmetry of information between consumers and producers, that can be the basis of discussion for alternative labelling schemes involving fair labour labels. We also tested a number of known biases associated with consumer behaviour or the contingent valuation method and found the positive willingness-topay result to be robust.
Sammendrag
Consumer resistance against GM crops is still substantial in the United States and Europe. We conducted an internet survey in the United States and Norway with more than 1,000 respondents in each country to estimate consumers’ willingness to pay (WTP) for GM soybean oil, farmed salmon fed with GM soy, and GM salmon. The differences in WTP for the conventional as compared with the GM alternatives are relatively small. Only between 7 and 13% of the respondents indicated that they were willing to pay more than a 20% premium for each of the conventional alternatives as compared to the corresponding GM alternatives. The average WTP premiums range from 7.5 to 9.2%. This suggests a large similarity in WTP in Norway and the United States and across the three products.
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Stef Bokhorst Laura Jaakola Katja Karppinen Guro Kristine Edvinsen Hanne Mæhre Jarle W. BjerkeSammendrag
Main conclusion Evergreen plants are more vulnerable than grasses and birch to snow and temperature variability in the sub-Arctic. Most Arctic climate impact studies focus on single factors, such as summer warming, while ecosystems are exposed to changes in all seasons. Through a combination of field and laboratory manipulations, we compared physiological and growth responses of dominant sub-Arctic plant types to midwinter warming events (6 °C for 7 days) in combination with freezing, simulated snow thaw and nitrogen additions. We aimed to identify if different plant types showed consistent physiological, cellular, growth and mortality responses to these abiotic stressors. Evergreen dwarf shrubs and tree seedlings showed higher mortality (40–100%) following extreme winter warming events than Betula pubescens tree seedlings and grasses (0–27%). All species had growth reductions following exposure to − 20 °C, but not all species suffered from − 10 °C irrespective of other treatments. Winter warming followed by − 20 °C resulted in the greatest mortality and was strongest among evergreen plants. Snow removal reduced the biomass for most species and this was exacerbated by subsequent freezing. Nitrogen increased the growth of B. pubescens and grasses, but not the evergreens, and interaction effects with the warming, freezing and snow treatments were minor and few. Physiological activity during the winter warming and freezing treatments was inconsistent with growth and mortality rates across the plants types. However, changes in the membrane fatty acids were associated with reduced mortality of grasses. Sub-Arctic plant communities may become dominated by grasses and deciduous plants if winter snowpack diminishes and plants are exposed to greater temperature variability in the near future. C-repeat binding factor · Fatty acids · Frost · Grass · Multiple stresses · Shrub · Snow
Forfattere
Knut ØistadSammendrag
Det er ikke registrert sammendrag