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
Miljømål i landbruksvassdrag oppgis gjerne som grenseverdier for gjennomsnittskonsentrasjoner av fosfor og nitrogen. For å finne miljømålet må vi vite noe om hva som er naturlige bakgrunnsverdier for disse næringsstoffene, altså hva ‘referansetilstanden’ er. På landbruksareal med marin leire er dette en stor utfordring. Dette skyldes dels at disse områdene gjerne har vært dyrket opp i århundrer; og dels at marin leire inneholder fosforrike mineraler. Vår målsetning har vært å anslå hvor mye fosfor som ville ha blitt tilført vannforekomstene fra et areal med marin leire hvis arealet ikke var oppdyrket, men befant seg i en naturtilstand (skog/utmark). Spørsmålet er relevant i forbindelse med gjennomføring av arbeidet med vannforskriften, og er viktig både for miljø‐ og landbruksforvaltningen. Prosjektets hovedfinansiører er Norges forskningsråd (Matprogrammet) og Stiftelsen fondet for jord‐ og myrundersøkelser.
Sammendrag
Phosphorus (P) is one of the main limiting factors for crop productivity while rhizosphere organic anions have been hypothesized to play an important role in P acquisition. Sampling in a long-term field experiment was carried out in order to understand the impact of long-term differences in P fertilization on secretion of organic anions under field conditions. Rhizosphere organic anions were extracted and analyzed every week from three leaves stage to completed flowering stage of wheat (Triticum aestivum) grown on plots that have received 0 (P0) or 48 (P48) kg P ha−1 year−1 since 1966. The study showed that it is possible to extract and quantify rhizosphere organic anions from field plots. In P48 plots, root P concentrations decreased around 40 % at the early stages (before heading), compared with the first sampling, and then increased slightly, while plants grown in P0 plots showed the opposite trend. Malate was the main organic anion secreted throughout all the wheat growth stages. Rhizosphere citrate and malate showed negative and positive correlations (P < 0.05) respectively with root P concentrations at 29 and 42 days after emergence (DAE). Rhizosphere organic anion concentrations were quite low until 29 DAE and then increased up to 4–10-fold until 42 DAE; these concentrations declined at later stages, indicating that root-released organic anions may have been affected by developmental stage and root P concentration. The present study provides valuable information about the relationship between rhizosphere organic anions and various P concentrations of wheat grown in the field.
Sammendrag
Application of fish sludge as fertiliser to agricultural land can contribute to closing nutrient cycles in fish farming. The effect of different treatment technologies on the nitrogen fertilisation effects of fish sludge was studied by a bioassay with barley (Hordeum vulgare), an incubation and a field experiment. Dried fish sludge resulted in relative agronomic efficiency of 50–80% compared with mineral fertiliser. The anaerobic digestate based on fish sludge (20 vol%) and dairy manure did not increase nitrogen uptake in barley. Increasing the ratio of fish sludge in the digestate increased the fertilisation effect, but requires optimisation of the biogas process. A simple logistics analysis conducted for a case hatchery showed that on-site drying and co-digestion of fish sludge in a central biogas plant can be regarded as equal in terms of costs. Norway can become an exporter of fish sludge-based recycling fertilisers if current regulations are modified to facilitate nutrient recycling.
Sammendrag
Klima- og miljødepartementet har via Miljødirektoratet gitt NIBIO i oppdrag å kartlegge synergieffektene for fellessatsing på vann-, luftforurensnings- og klimatiltak i jordbruket. Agronomiske og produksjonsmessige effekter er også belyst, og det er gitt en vurdering av effekt for biologisk mangfold og andre miljøverdier. For å nå internasjonale og nasjonale mål innen vannmiljø, klimagassutslipp og luftforurensing innen gitte tidsrammer, er det behov for en opptrapping av miljøinnsatsen i jordbrukssektoren. Samtidig er det et nasjonalt mål om å øke matproduksjonen og det er nye utfordringer med tilpasninger til endret klima. Dette gir et større behov for å vurdere mål, tiltak og virkemidler i sammenheng for mulige synergier. Vannforvaltningsplanene viser at det er til dels store gap mellom dagens tilstand i næringsrike vassdrag og de fastsatte miljømålene. Norge har heller ikke oppnådd målene i Nordsjøavtalene. Oppfølging av vannforvaltningsplanene vil derfor kreve økt tiltaksgjennomføring i jordbruket for å nå de bindende mål om god vannmiljøtilstand for perioden 2016 - 2021 samt etterfølgende perioder 2022 - 2027 og 2028 -2033. Endringer i klima med risiko for mer nedbør, våtere forhold og økt avrenning kan gjøre det mer krevende å oppnå miljømålene. Det kan gi forsterket behov for tiltak, behov for nye tiltak og endringer i prioriteringer av tiltak. Ekstremvær kan gi stor risiko for flomskade og utrasinger på jordbruksareal, noe som krever egne beskyttelsestiltak, men også til økt risiko for store avrenningsepisoder med tap fra selve jordbruksarealene. Våtere forhold kan gjøre det vanskeligere å oppfylle miljømålene for vannkvalitet og aktualisere større behov for å målrette tiltak til utsatte/prioriterte vassdrag og bruk av forpliktende miljøavtaler...
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
presentasjon resultater prosjekter relatert drenering
Sammendrag
Area-efficient constructed systems for stormwater management and bioretention may involve large fluc-tuations in subsurface water levels. Such fluctuations challenge vegetation by forcing roots to exploredeeper layers to access water during dry periods. In a controlled experiment, we studied growth pat-terns and the ability of Phragmites australis roots to track subsurface water level fluctuations of differingamplitude and frequency in substrates with contrasting water-holding capacity. We found that P. aus-tralis was able to adjust its rooting pattern to considerable subsurface water level fluctuations (to wellbelow 120 cm), but that substrate characteristics can restrict its ability to adjust to larger fluctuations.Fluctuation amplitude was the driving factor for plant growth and biomass allocation responses, whilesubstrate characteristics and fluctuation frequency were less important. When not exposed to large waterlevel fluctuations, P. australis grew larger shoots and only explored intermediate rooting depths. Therewas a negative relationship between root and rhizome biomass, showing a resource-based trade-off andshort-term costs of adjusting rooting patterns to large water level fluctuations. These results indicatethat P. australis is suited for systems with considerable subsurface water fluctuations, but constraints onits flexibility need to be investigated.
Sammendrag
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Forfattere
Mihaela-Olivia Dobrica Catalin Lazar Lisa Paruch Hanne Skomedal Hege Særvold Steen Sissel Haugslien Catalin Tucureanu Iuliana Caras Adrian Onu Sonya Ciulean Alexandru Branzan Jihong Liu Clarke Crina Stavaru Norica Branza-NichitaSammendrag
Chronic Hepatitis B Virus (HBV) infection leads to severe liver pathogenesis associated with significant morbidity and mortality. As no curable medication is yet available, vaccination remains the most costeffective approach to limit HBV spreading and control the infection. Although safe and efficient, the standard vaccine based on production of the small (S) envelope protein in yeast fails to elicit an effective immune response in about 10% of vaccinated individuals, which are at risk of infection. One strategy to address this issue is the development of more immunogenic antigens. Here we describe a novel HBV antigen obtained by combining relevant immunogenic determinants of S and large (L) envelope proteins. Our approach was based on the insertion of residues 21-47 of the preS1 domain of the L protein (nomenclature according to genotype D), involved in virus attachment to hepatocytes, within the external antigenic loop of S. The resulting S/preS121-47 chimera was successfully produced in HEK293T and Nicotiana benthamiana plants, as a more economical recombinant protein production platform. Comparative biochemical, functional and electron microscopy analysis indicated assembly of the novel antigen into subviral particles in mammalian and plant cells. Importantly, these particles preserve both S- and preS1-specific epitopes and elicit significantly stronger humoral and cellular immune responses than the S protein, in both expression systems used. Our data promote this antigen as a promising vaccine candidate to overcome poor responsiveness to the conventional, S protein-based, HBV vaccine.
Forfattere
Jihong Liu Clarke Lisa Paruch Mihaela-Olivia Dobrica Iuliana Caras Catalin Tucureanu Adrian Onu Sonya Ciulean Crina Stavaru Andre van Eerde Hege Særvold Steen Sissel Haugslien Catalina Petrareanu Catalin Lazar Ioan Popescu Ralph Bock Jean Dubuisson Norica Branza-NichitaSammendrag
Det er ikke registrert sammendrag