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.
2024
Sammendrag
Manure spreading often leads to nutrient losses with negative environmental impacts, especially in cold climates where harsh winters can affect grass sward density. Nutrient efficiency in cattle slurry depends on the plant coverage at the start of the growing season. To simulate winter damage variation, random mechanical disturbance was applied to a grass field. Aerial images were obtained and analysed using the Grasision® tool to estimate plant cover. Three fixed treatments with uniform cattle slurry and N fertilizer application across all plots, and two treatments adjusting slurry and N fertilizer based on autumn or spring plant coverage were tested. Above-ground yield was measured post-first and second cut. Adjusting N rates based on spring plant coverage or using a low N rate resulted in similar agronomic N use efficiency as high N application rates, albeit with lower dry matter yield.
Forfattere
Annette Folkedal SchjøllSammendrag
Det er ikke registrert sammendrag
Sammendrag
This study investigated the effects of substrates composed of various ratios of wood fiber and peat (0, 25, 50, 75, and 100% peat (v/v)) mixed with different amounts of lime (0, 2, 4, 6, and 8 g L−1) and start fertilizer (0, 2, and 4 g L−1 Multimix) on the growth and biomass accumulation of petunia (Petunia x hybrida Vilm ‘Finity F1 Purple’) and basil (Ocimum basilicum L. ‘Marian’) in an ebb-and-flow greenhouse system. Growth parameters included plant height, weight, canopy diameter, and chlorosis symptoms for petunia, along with substrate pH and EC measurements. Petunia showed optimal growth in substrates with higher peat content, while basil produced satisfactory biomass across a pH range of 5–7 regardless of substrate type. Optimal petunia cultivation in 100% wood fiber required a significant dose of start fertilizer without lime. Monitoring pH and EC using pour-through and press methods revealed a pH decrease in substrates with added start fertilizer, while substrates with higher wood fiber content were less acidic. Substrates with over 50% (v/v) wood fiber without lime showed a rapid pH increase over five weeks. The pour-through method generally underestimated EC values compared to the press method. These findings contribute to optimizing the wood fiber/peat blends for sustainable horticulture.
Forfattere
Carl-Fredrik Johannesson Jenni Nordén Holger Lange Hanna Marika Silvennoinen Klaus Steenberg LarsenSammendrag
Non-steady-state chambers are often used for greenhouse gas flux measurements, and while there are recommendations on how long to keep the chamber closed, it is less investigated to what extent the length of the chamber closure period affects the estimated flux rates and which closure periods may provide the most accurate linear and non-linear flux estimates. Previous studies have shown that the closure of non-steady-state chambers induces a non-linear concentration development inside the chamber, even across short chamber closure periods, and that both linear and non-linear flux estimates are impacted by the chamber closure period itself. Based on 3,159 individual soil CO2 and CH4 flux measurements, we analyzed how linear regression and Hutchinson and Mosier (1981) modeled flux estimates are affected by the length of the chamber closure period by increasing it in increments of 30 sec, with a minimum and maximum chamber closure period of 60 and 300 sec, respectively. Across all detected flux measurements, the effect of chamber closure period length varied between 1.4–8.0 % for linear regression estimates and between 0.4–17.8 % for Hutchinson–Mosier estimates, and the largest effect sizes were observed in high flux regions. While both linear regression and Hutchinson–Mosier based estimates decreased as the chamber closure period increased, we observed a clear convergence of flux estimates as shorter and longer chamber closure periods were used for linear regression and Hutchinson–Mosier based estimation, respectively. This suggests using closure periods as short as possible for linear regression flux estimation or ensuring long-enough closure periods to observe a stabilization of Hutchinson–Mosier flux estimates over time. This analysis was based on soil flux measurements, but because the perturbation of the concentration gradient is related to the non-steady-state chamber technique rather than the measured ecosystem component, our results have implications for all flux measurements conducted with non-steady-state chambers. Non-steady-state Static chamber Closure period Concentration gradient Hutchinson–Mosier Minimum detectable flux
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Eva BrodSammendrag
Det er ikke registrert sammendrag
Forfattere
Eva BrodSammendrag
Det er ikke registrert sammendrag
Sammendrag
• For more than 20 years, methyl jasmonate (MeJA) has been used to study inducible defenses in conifers and to increase tree resistance to pests and pathogens. Despite the numerous studies on the subject, no attempts have been made to summarize or quantify how MeJA affects resistance and growth in conifers. Here we present a quantitative meta-analysis of the effects of MeJA treatment on the conifer genera Pinus and Picea, two of the most economically and ecologically important tree genera in boreal, temperate, and alpine forests. • A literature search yielded 120 relevant papers. We summarized the key experimental methods used in these papers and performed a meta-analysis of how MeJA affects tree growth and resistance to pests and pathogens. • The results show that MeJA negatively affects tree growth, with an overall effect size of −0.63. The overall effect size of MeJA for tree resistance was −0.76, indicating that MeJA treatment significantly reduces tree damage caused by biotic stressors. • Although our meta-analysis shows that MeJA is effective in enhancing conifer defenses, there are still gaps in our understanding of the durability and ecological consequences of MeJA treatment. We provide suggestions for how future research should be conducted to address these gaps.
Forfattere
Marit Skuterud VennatrøSammendrag
Formålet med oppdraget var å undersøke om potetcystenematode (PCN) overlever etter behandling med vanndamp i SoilSaver. Resultatene viser at varmebehandling med damp i SoilSaver påvirker potetcystemenatode sin nevne til å klekke fra eggene. Det er ikke funnet larver eller egg som har overlevd behandling i noen av gjentakene.
Sammendrag
Gjennom stedfesting av ferdigplenarealer, spørreundersøkelse og intervju med ferdigplenprodusenter er det fremskaffet informasjon om omfang, arealressurser, driftsteknikk og produsentperspektiv i norsk ferdigplenproduksjon per 2021. Undersøkelsen dekker omtrent 2/3 av de kjente norske ferdigplenprodusentene og anses å ha nasjonal overføringsverdi. Stedfestingen viste at 6000-7000 daa brukes i denne produksjonen. To tredjedeler av produksjonen foregår på lette mineraljordarter med god naturlig dreneringsevne, små begrensninger, og gode agroklimatiske forhold, mens resterende tredjedel foregår på tyngre jord. Resultater fra spørreundersøkelse og intervju med produsenter viser at gjennomsnittlig omløpstid for ferdigplen i Norge er drøye to år og at om lag halvparten av produsentene tilfører organisk materiale i tillegg til tilbakeføring av avklipp. Ferdigplenproduksjon setter store krav til såbedet og jordarbeidinga kan være intensiv, men er mindre hyppig enn annen jordbruksproduksjon. Gjødselbruken er moderat og bruken av plantevernmidler sparsom. Ferdigplenarealene overvintrer som regel i grasdekke eller som nyhøsta, ikke-jordbearbeida areal. Rapporten påpeker verdien av det fremlagte tallgrunnlaget i kombinasjon med resultater fra forsøk og registeringer i felt i prosjektet ‘Bærekraftig produksjon av ferdigplen’, internasjonal litteratur og framtidige forskingsprosjekter.