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.
2006
Forfattere
Olaug BergsetSammendrag
Utfordringer, muligheter og tilnærmingsmåter for utvikling av nordnorske bygdesamfunn som gjennomgår store endringer. Vi ønsker det gode liv, med bomiljø, et levebrød og gode oppvekstvilkår. Folk sin motivasjon for å leve i bygdesamfunn. Forbrukertrender under utvikling er i favør av "bygdeprodukt". Finne lokalsamfunnets fortrinn og særpreg og bygge videre på det. Åpne og inkluderende nettverk mot omverdenen er viktig.
Sammendrag
Freezing and thawing influence the transport potential and pathways for contaminants by altering the soil physical properties. Firstly, soil frost delays or impedes infiltration of rain and meltwater, reducing the transport rate of dissolved contaminants. But at the same time, particle bound contaminants may be mobilised because the reduced infiltration capacity increases surface runoff and erosion risk. Secondly, freezing water expands and imposes mechanical stresses on the soil, which may cause aggregate breakdown and facilitate particle detachment and transport. The influence of repeated freezing and thawing on aggregate stability of different soils is poorly documented for Nordic winter conditions. The purpose of this study (Kværnø and Øygarden, subm.) was to quantify the effect of variable freeze-thaw cycles and soil moisture conditions on aggregate stability of three soils: Silt, structured clay loam (Clay A) and artificially levelled silty clay loam (Clay B). These soils are representative of two erosion prone areas in South-eastern Norway. Field moist surface soil was sieved into the fraction 1- 4 mm, and packed into cylinders. The water content of the soil was adjusted, corresponding to matric potentials of -0.75, -2 and -10 kPa. The soil cores were insulated and covered, and subjected to 0, 1, 3 or 6 freeze-thaw cycles: freezing at "15"C for 24 hours, and thawing at 9"C for 48 hours. Aggregate stability was measured in a rainfall simulator (representing rainfall) and a wet-sieving apparatus (representing surface runoff). The aggregate stability of Silt was found to be significantly lower than of Clay A and Clay B. Clay A and Clay B had similar aggregate stabilities, even if it was expected that the artificially levelled Clay B would have lower stability. Freezing and thawing decreased the aggregate stability for all three soils, but the effect was more severe on the silt soil. There was no evident effect of water content on the aggregate stability, probably due to experimental limitations. The wet-sieving apparatus resulted in less aggregate breakdown than the rainfall simulator. Rainfall impact seemed to be more detrimental than wet-sieving the more unstable the soil was, that is, after many freeze-thaw cycles, and on silt soil. The results indicate that freezing and thawing is an important factor influencing the erosion risk of the studied soils. In the future, climate change is expected to give more unstable winters with more freezing and thawing events. Combined with more precipitation as rainfall during the winter period both runoff and erosion will probably increase, possibly resulting in heavier loads of particulate bound contaminants to surface waters. The results are also helpful for improving predictions of contaminant fate and transport, as most of the existing hydrological and soil erosion prediction models do not satisfactorily describe soil processes occurring under Nordic winter conditions. This study focused on arable soils with conventional agricultural management, where plant nutrients and pesticides pose a threat to water quality. It would be useful to conduct similar experiments on soils where other organic and inorganic contaminants are of concern, e.g. on soils where sewage sludge and compost have been applied, and soils in road cuttings and on contruction sites. References Kværnø, S.H. & Øygarden, L. submitted: The influence of freeze-thaw cycles and soil moisture on aggregate stability of three soils in Norway.
Sammendrag
Freezing and thawing influence the transport potential and pathways for contaminants by altering the soil physical properties. Firstly, soil frost delays or impedes infiltration of rain and meltwater, reducing the transport rate of dissolved contaminants. But at the same time, particle bound contaminants may be mobilised because the reduced infiltration capacity increases surface runoff and erosion risk. Secondly, freezing water expands and imposes mechanical stresses on the soil, which may cause aggregate breakdown and facilitate particle detachment and transport. The influence of repeated freezing and thawing on aggregate stability of different soils is poorly documented for Nordic winter conditions. The purpose of this study (Kværnø and Øygarden, subm.) was to quantify the effect of variable freeze-thaw cycles and soil moisture conditions on aggregate stability of three soils: Silt, structured clay loam (Clay A) and artificially levelled silty clay loam (Clay B). These soils are representative of two erosion prone areas in South-eastern Norway. Field moist surface soil was sieved into the fraction 1- 4 mm, and packed into cylinders. The water content of the soil was adjusted, corresponding to matric potentials of -0.75, -2 and -10 kPa. The soil cores were insulated and covered, and subjected to 0, 1, 3 or 6 freeze-thaw cycles: freezing at "15"C for 24 hours, and thawing at 9"C for 48 hours. Aggregate stability was measured in a rainfall simulator (representing rainfall) and a wet-sieving apparatus (representing surface runoff). The aggregate stability of Silt was found to be significantly lower than of Clay A and Clay B. Clay A and Clay B had similar aggregate stabilities, even if it was expected that the artificially levelled Clay B would have lower stability. Freezing and thawing decreased the aggregate stability for all three soils, but the effect was more severe on the silt soil. There was no evident effect of water content on the aggregate stability, probably due to experimental limitations. The wet-sieving apparatus resulted in less aggregate breakdown than the rainfall simulator. Rainfall impact seemed to be more detrimental than wet-sieving the more unstable the soil was, that is, after many freeze-thaw cycles, and on silt soil. The results indicate that freezing and thawing is an important factor influencing the erosion risk of the studied soils. In the future, climate change is expected to give more unstable winters with more freezing and thawing events. Combined with more precipitation as rainfall during the winter period both runoff and erosion will probably increase, possibly resulting in heavier loads of particulate bound contaminants to surface waters. The results are also helpful for improving predictions of contaminant fate and transport, as most of the existing hydrological and soil erosion prediction models do not satisfactorily describe soil processes occurring under Nordic winter conditions. This study focused on arable soils with conventional agricultural management, where plant nutrients and pesticides pose a threat to water quality. It would be useful to conduct similar experiments on soils where other organic and inorganic contaminants are of concern, e.g. on soils where sewage sludge and compost have been applied, and soils in road cuttings and on contruction sites. References Kværnø, S.H. & Øygarden, L. submitted: The influence of freeze-thaw cycles and soil moisture on aggregate stability of three soils in Norway.
Forfattere
Marianne Stenrød Marit Almvik Jeanne Perceval Pierre Benoit Marie-Paule Charnay Ole Martin Eklo Randi Bolli Tore Sveistrup Jens KværnerSammendrag
Little research has been done on pesticide dissipation under cold climates, and there is a need to focus on the influence of climate on pesticide degradation and transport in soil. Glyphosate " a herbicide frequently used for controlling perennial weeds through application after fall " and metribuzin " a herbicide used for controlling annual grasses and broadleaved weeds in potato in Norway " were used as model compounds for this study. The investigations were set up to study if soil frost affects the mobility of pesticides, and increases the risk of leaching on release of a frost period. ... This report on slow mineralization of pesticides under cold climatic conditions, as well as an increased risk of pesticide leaching on release of soil frost, point out the importance of taking the occurrence of soil freezing during winter into account in risk evaluations and pesticide fate prediction models for regions with a cold climate.
Forfattere
Marianne StenrødSammendrag
Det er ikke registrert sammendrag
Forfattere
Dag-Ragnar BlystadSammendrag
Friskt, sortsekte utgangsmateriale for formering av vegetativt formerte vekster er et viktig tiltak for å bekjempe virus og bakterier. Enkelte arter av sopp, nematoder og insekter kan også følge plantematerialet, og et friskt formeringsmateriale er en forutsetning for en vellykket bekjempelse. Prosessen for å framstille et slikt materiale kalles fremavl. Fremavl krever samspill mellom brukere, foredlere, FoU-miljøer, kontrollorganer og politiske myndigheter. Et slikt samspill er godt utviklet i Norge og gir sammen med et kjølig klima og god avstand mellom produksjonsenhetene gode muligheter for produksjon av friskt plantemateriale. Artiklen beskriver det norske fremavlssystemet og beskriver eksempler på vellykket bruk og markedsføring av fremavls-materiale av blomster og grøntanleggsplanter.
Forfattere
Nina HeibergSammendrag
Satsing på nye arter er en tidkrevende prosess, som krever stor innsats fra både forskning, planteforedling og næringen selv. Det er vanskelig å skaffe finansiering til langsiktig forskning på nye arter, næringen er nødt til å være med i arbeidet fra starten. Det er også et positivt aspekt i dette, når næringen er involvert vil det være lettere å få produktene ut på markedet. En viktig faktor for suksess er at en får prøvd ut tilstrekkelig med genetisk materiale, og at en velger ut sorter/arter som har en mulighet for å vokse i vårt klimaområde. En bør derfor bruke tid på å få tak i det mest egnete plantemateriale, før en starter. Internasjonalt samarbeid er viktig i denne fasen. Dessuten må en sikre seg at en ikke får med seg farlige planteskadegjørere ved import. Frukt og bær er flerårige vekster, derfor er utprøvingen både dyr og tidkrevende. Den innledende utprøvingen bør foregå på forskningsinstitusjoner, fordi store forsøk med mange sorter er vanskelig å tjene penger på, men så snart en kan velge ut ett fåtalls aktuelle sorter bør disse plantes ut hos produsenter. I
Forfattere
Silje Aase Wolff Anne LangerudSammendrag
Det er ikke registrert sammendrag
Forfattere
Eivind VangdalSammendrag
I artikkelen gjennomgår ein fruktkvalitet og dyrkingseigenskapar for dei mest aktuelle tidlege eplesortane.
Forfattere
Stein Harald Hjeltnes John Harald Rønningen Torbjørn Takle Jan Meland Tomas HesthamarSammendrag
Artikkelen er ein syntese av rapporten "Analyse av norsk frukttrekvalitet i høve til norsk kjernefruktproduksjon" utarbeidd og finansiert av Gartnerhallen i 2005. Det vert her sett fokus på dei problema som både fruktdyrkarar, planteskular og Gartnerhallens Eliteplantestasjon står overfor, og det er føreslått tiltak ut frå ulike scenarier - med eksisterande planthelselovgjeving og ved å ta i bruk EU sitt plantehelsedirektiv.