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.
2019
Forfattere
Håvard Steinshamn Jan Karstein Henriksen Finn Walland Geir Næss Eystein Ystad Anne Kjersti BakkenSammendrag
•Blandingseng med rødkløver og gras høsta to ganger i sesongen gir lavere grovfôrkostnader sammenlignet med tre slåtter per år i blandingseng eller timoteibasert eng som høstes to eller tre ganger. •Blandingsenga slått to ganger per sesong gir også lavest total fôrkostnad (grovfôr + kraftfôr) selv om treslåttsystemene reduserte behovet for kraftfôr. • Sjøl om en kan bruke mindre og billigere kraftfôr ved tre slåtter, greier en ikke å dekke inn de høyere dyrkings- og høstekostnadene. • Femårig engomløp kommer generelt bedre ut økonomisk enn treårig, selv om avlingsnivået er litt lavere. Avlingsøkninga kompenserer ikke for de økte dyrkingskostnadene. • Blandingseng med kløver, som er moderat gjødsla og høsta to ganger per år, gir lavest kostnad, totalt for grovfôr + kraftfôr, og er mest arealeffektivt med dagens kraftfôrpris
Forfattere
Jørgen Eilenberg Stephanie Saussure Ibtissem Ben Fekih Annette Bruun Jensen Ingeborg KlingenSammendrag
Pandora neoaphidis and Entomophthora planchoniana are widespread and important specialist fungal pathogens of aphids in cereals (Sitobion avenae and Rhopalosiphum padi). The two aphid species share these pathogens and we compare factors influencing susceptibility and resistance. Among factors that may influence susceptibility and resistance are aphid behavior, conspecific versus heterospecific host, aphid morph, life cycle, and presence of protective endosymbionts. It seems that the conspecific host is more susceptible (less resistant) than the heterospecific host, and alates are more susceptible than apterae. We conceptualize the findings in a diagram showing possible transmission in field situations and we pinpoint where there are knowledge gaps.
Forfattere
Inga Greipsland Johanna Skrutvold Roger Roseth Øistein Johansen Thor Endre Nytrø Rikard Pedersen Jonas ReinemoSammendrag
På oppdrag fra Bane NOR har NIBIO overvåket vannkvalitet i resipienter som kan motta avrenning fra anleggsarbeider i forbindelse med Follobanen.NIBIO har driftet opp til 9 automatiske målestasjoner utstyrt med multiparametersensorer for overvåking av vannkvalitet. I tillegg har det blitt tatt ut vannprøver ved 14 stasjoner og utført biologiske undersøkelser ved 4 stasjoner samt i Gjersrudtjern. Overvåkingen har pågått i bekker nedstrøms riggområdet på Åsland, i bekker sør for stasjonsområdet på Ski og langs anleggsområdet mellom Ski og Langhus. Årsrapporten omfatter alle resultater samlet inn på disse stasjonene i 2018 og har blitt sammenlignet med tidligere resultater.
Sammendrag
In autumn, agricultural perennial weeds prepare for winter and can store reserves into creeping roots or rhizomes. Little is known about influence of climate change in this period. We tested the effect of simulated climate change in autumn on three widespread and noxious perennial weeds, Elymus repens (L.) Gould, Cirsium arvense (L.) Scop. and Sonchus arvensis L. We divided and combined simulated climate change components into elevated CO2 concentration (525 ppm), elevated temperatures (+2–2.5°C), treatments in open‐top chambers. In addition, a control in the open‐top chamber without any increase in CO2 and temperature, and a field control outside the chambers were included. Two geographically different origins and three pre‐growth periods prior to the exposure to climate change factors were included for each species. All species increased leaf area under elevated temperature, close to doubling in E. repens and quadrupling in the dicot species. E. repens kept leaves green later in autumn. C. arvense did not benefit in below‐ground growth from more leaf area or leaf dry mass. S. arvensis had low levels of leaf area throughout the experiment and withered earlier than the two other species. Below‐ground plant parts of S. arvensis were significantly increased by elevated temperature. Except for root:shoot ratio of C. arvense, the effects of pure elevated CO2 were not significant for any variables compared to the open‐top chamber control. There was an additive, but no synergistic, effect of enhanced temperature and CO2. The length of pre‐growth period was highly important for autumn plant growth, while origin had minor effect. We conclude that the small transfer of enhanced above‐ground growth into below‐ground growth under climate change in autumn does not favour creeping perennial plants per se, but more leaf area may offer more plant biomass to be tackled by chemical or physical weed control.
Sammendrag
Aim: Many countries lack informative, high‐resolution, wall‐to‐wall vegetation or land cover maps. Such maps are useful for land use and nature management, and for input to regional climate and hydrological models. Land cover maps based on remote sensing data typically lack the required ecological information, whereas traditional field‐based mapping is too expensive to be carried out over large areas. In this study, we therefore explore the extent to which distribution modelling (DM) methods are useful for predicting the current distribution of vegetation types (VT) on a national scale. Location: Mainland Norway, covering ca. 324,000 km2. Methods: We used presence/absence data for 31 different VTs, mapped wall‐to‐wall in an area frame survey with 1081 rectangular plots of 0.9 km2. Distribution models for each VT were obtained by logistic generalised linear modelling, using stepwise forward selection with an F‐ratio test. A total of 116 explanatory variables, recorded in 100 m × 100 m grid cells, were used. The 31 models were evaluated by applying the AUC criterion to an independent evaluation dataset. Results: Twenty‐one of the 31 models had AUC values higher than 0.8. The highest AUC value (0.989) was obtained for Poor/rich broadleaf deciduous forest, whereas the lowest AUC (0.671) was obtained for Lichen and heather spruce forest. Overall, we found that rare VTs are predicted better than common ones, and coastal VTs are predicted better than inland ones. Conclusions: Our study establishes DM as a viable tool for spatial prediction of aggregated species‐based entities such as VTs on a regional scale and at a fine (100 m) spatial resolution, provided relevant predictor variables are available. We discuss the potential uses of distribution models in utilizing large‐scale international vegetation surveys. We also argue that predictions from such models may improve parameterisation of vegetation distribution in earth system models.
Forfattere
Siri Svendgård-Stokke Hege Ulfeng Lise Dalsgaard Stephanie Eisner Roar Lågbu Ove Mindor Klakegg Eivind Solbakken Gunnhild Søgaard Geir-Harald StrandSammendrag
Denne rapporten skal gi grunnlag for å vurdere en eventuell leveranse av et kart som viser organisk karbon i norsk jordsmonn til FAO. Rapporten redegjør for bestillingen fra FAO, inkludert FAOs beskrivelse av formål og nytte av et Global Soil Organic Carbon Map (GSOCmap). Rapporten gir også en kort oversikt over hvordan GSOCmap er utarbeidet i våre naboland, og hvordan arbeidet med et nytt kart kan ses i sammenheng med Global Soil Partnership (GSP) og annet relevant arbeid NIBIO er involvert i. Rapporten skisserer fire alternativer for hvordan et SOC kart for Norge til bruk i GSOCmap kan utarbeides.
Forfattere
Jan Magnusson Stephanie Eisner Shaochun Huang Cristian Lussana Giulia Mazzotti Richard Essery Tuomo Saloranta Stein BeldringSammendrag
Climate models show that global warming will disproportionately influence high‐latitude regions and indicate drastic changes in, among others, seasonal snow cover. However, current continental and global simulations covering these regions are often run at coarse grid resolutions, potentially introducing large errors in computed fluxes and states. To quantify some of these errors, we have assessed the sensitivity of an energy‐balance snow model to changes in grid resolution using a multiparametrization framework for the spatial domain of mainland Norway. The framework has allowed us to systematically test how different parametrizations, describing a set of processes, influence the discrepancy, here termed the scale error, between the coarser (5 to 50‐km) and finest (1‐km) resolution. The simulations were set up such that liquid and solid precipitation was identical between the different resolutions, and differences between the simulations arise mainly during the ablation period. The analysis presented in this study focuses on evaluating the scale error for several variables relevant for hydrological and land surface modelling, such as snow water equivalent and turbulent heat exchanges. The analysis reveals that the choice of method for routing liquid water through the snowpack influences the scale error most for snow water equivalent, followed by the type of parametrizations used for computing turbulent heat fluxes and albedo. For turbulent heat exchanges, the scale error is mainly influenced by model assumptions related to atmospheric stability. Finally, regions with strong meteorological and topographic variability show larger scale errors than more homogenous regions.
Forfattere
Marit Almvik Nina Elisabeth Nagy Hans Ragnar Norli Ari Hietala Sven R. Odenmarck Monica Fongen Anas KamlehSammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Kandidatsortene av engvekstartene tas opp på den offisielle norske sortslista ut fra prøvinger i reinbestand. De fleste dyrkes imidlertid i artsblandinger, og det kan være grunn til å se på om sortsrangeringen fra innledende prøvinger speiles når artene brukes i slike blandinger.