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.
2013
Sammendrag
Tap av nitrogen med grøfte- og overflatevatn frå eng er særleg påverka av nedbørsmengde, tidspunkt for spreiing av gjødsel, jordart, kor sterkt det er gjødsla og driftsmåte elles. Kva gjødselslag som er nytta, hysdyrgjødsel eller handelsgjødsel, synest i mindre grad å verka inn.
Forfattere
Liv Østrem Samson ØpstadSammendrag
Med auka fokus på grovfôrkvalitet og ein lengre vekstsesong, er ei godt drenert jord viktig for at bonden raskast råd kan koma ut på jordet, både om våren for jordarbeiding og gjødsling og for å hausta i vekstsesongen.
Forfattere
Ivar HovlandSammendrag
Lønnsomheten ved grøfting bør vurderes ut fra et helhetssyn der kostnadene måles mot høyere avling, bedre driftsmessige forhold og økt fleksibilitet i bruken av jorda. Anleggets forventede levetid og rentenivå betyr også mye for lønnsomheten ved grøfting.
Forfattere
Jarle Werner Bjerke Stef Bokhorst Terry V. Callaghan Matthias Zielke Gareth K. PhoenixSammendrag
Background: Arctic lichens and mosses are covered by snow for more than half the year and are generally considered as being dormant for most of this period. However, enhanced frequency of winter warming events due to climate change can cause increased disturbance of their protective subnivean environment. Aim: To further understand cryptogamic responses to mid-winter warming we compared the ecophysiological performance of one lichen and one moss species during a simulated warming event. Methods: We measured photosynthesis and dark respiration in samples of the moss Hylocomium splendens and the lichen Peltigera aphthosa removed from under snow, and on natural refreezing after the warming event, which was simulated by using infrared heaters suspended above the ground. Results: The moss exposed to light at +5 °C immediately after removal from their subnivean environment and from warmed plots showed positive net gas exchange within 332 s; the lichen required 1238 s. Photosynthesis and nitrogen fixation rates were equal to that, or higher than, during the preceding growing season. Upon refreezing after the event, moss photosynthesis declined considerably. Conclusions: The moss, and to a lesser extent the lichen, may contribute to subnivean midwinter ecosystem respiration, and both are opportunistic, and can take advantage of warmer winter phases for photosynthesis and growth. This ought to be taken into account in vegetation change projections of cryptogam-rich ecosystems. carbon flux; climate change; cryptogams; dormancy; gas exchange; nitrogen fixation; reactivation; snow melt; subnivean environment; winter warming
Forfattere
William White Anders Lunnan Erlend Nybakk Biljana KulisicSammendrag
The renewable energy sector (RES) often receives financial, institutional or educational support from the government. A significant challenge for the actors in the RES field is policy consistency. When investments are carried out, a prognosis for future policies must be made. If the future is uncertain, larger risk margins should be included in the investment appraisals. Sudden, unexpected policy changes are one type of uncertainty that makes it more difficult to attract capital. In this article, we discuss the consequences of discontinuities in policy support using a case study approach. In Ontario, feed-in tariffs were introduced in 2009 and resulted in a large uptake in the programme. In 2010, the subsidies were drastically cut, resulting in the RES community losing confidence that the government would offer consistent support to the sector. In Norway, a large new biodiesel plant was opened by the Minister of the Environment only a few weeks before the government announced a major change in the bioenergy policy. As a result, the new plant was closed and restructured, and the investors lost nearly all of their investments. The government lost political credibility, making it difficult to raise private capital for new investments in this sector in Norway. We do not argue that policies should not be changed, but the manner in which policies are changed plays an important role. Our study shows that large, unexpected changes in policies increase uncertainty and may have a negative impact on investments. This topic should be further researched.
Forfattere
Mekjell Meland Eva Birken Clive KaiserSammendrag
Crop load adjustments in European plum trees (Prunus domestica L.) require thinning either by hand (mechanical) or chemical means to achieve marketable size, fruit quality and to overcome alternate bearing. Efficient tools for crop load management are highly desirable, since only a few chemical thinners are registered and hand thinning is labor intensive and costly. Gibberellic acid (GA3) was tested as a novel approach to regulate the crop load of the plum cultivar ‛Opal’ at Ullensvang, western Norway. The objective was to reduce flower bud induction in the “off-year” thus adjusting crop load the subsequent year. In 2008, an “off-year”, GA3 was applied to 9 year-old ‘Opal’ trees as a high volume spray to the point of run-off at 50 ppm or 100 ppm at either 5 weeks after full bloom or 10 weeks after full bloom, or on both dates and compared with untreated control trees. Trees were unthinned the first year but then thinned to commercial standard the following year. In the year of application, total yield was recorded and fruit quality evaluated. Return bloom, fruit set, yield and fruit quality were assessed the subsequent year. In general, there were no significant differences in crop load of all treated trees compared to untreated trees in the year of application (non-target crop) however, fruit weight increased slightly on those trees when GA3 was applied 5 weeks after full bloom compared to all other treatments and untreated trees. The following year (target crop) fruit set was significantly reduced for all GA3 treatments. The most effective application time was 5 weeks after full bloom. Before thinning, initial fruit set was greatest on untreated trees as well as on those trees treated with GA3 10 weeks after full bloom. Fruit weight and fruit colour were significantly better on trees with the least fruit set. GA3 applications had no effect on fruit firmness. It is concluded that GA3 is an effective tool for inhibiting flower bud induction in an “off-year” thus enabling crop load management the subsequent “on-year”.
Sammendrag
The distribution of Leiopus nebulosus (Linnaeus, 1758) and L. linnei Wallin, Nylander & Kvamme, 2009, in Norway is discussed and depicted. Observations of host trees as well as information of substrate qualities and phenology are included.
Forfattere
John A. Finn Laura Kirwan John Connolly Maria Teresa Sebastia Aslaug Helgadottir Ole Hans Baadshaug Gilles Bélanger Alistair Black Caroline Brophy Rosemary P. Collins Jure Cop Sigridur Dalmannsdottir Ignacio Delgado Anjo Elgersma Michael Fothergill Bodil Frankow-Lindberg An Ghesquiere Barbara Golinska Piotr Golinski Philippe Grieu Anne-Maj Gustavsson Mats Höglind Olivier Huguenin-Elie Marit Jørgensen Zydre Kadziuliene Päivi Kurki Rosa Llurba Tor Lunnan Claudio Porqueddu Matthias Suter Ulrich Thumm Andreas LüscherSammendrag
Det er ikke registrert sammendrag
Forfattere
Halvor SolheimSammendrag
Common juniper (Juniperus communis) hosts not many pests or pathogens, but recently increasing needle blight has been observed in Norway. During a survey the needle blight was recorded in many parts of southern Norway but not above 550 m a.s.l., and it has been found both in forests, pastures and gardens. Trees are affected differently; some trees seem to be unaffected, while other trees may be killed. The cause of the disease is a fungus in the family Mycosphaerellaceae hitherto not reported from Norway. In forest pathology literature it has been named Stigmina juniperina, but also Asperisporium juniperinum. However, based on results of molecular sequence analyses it is proposed here that a more appropriate name should be Passalora juniperina (Georgescu & Badea) H. Solheim comb. Nov.
Forfattere
Kerry O'Donnell Alejandro P. Rooney Robert Proctor Daren W. Brown Susan P. McCormick Todd J. Ward Rasmus J. N. Frandsen Erik Lysøe Stephen A. Rehner Takayuki Aoki Vincent A.R.G Robert Pedro W. Crous Johannes Z. Groenewald Seogchan Kang David M. GeiserSammendrag
Det er ikke registrert sammendrag