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.
2003
Forfattere
Anne-Kristin Løes Anne Falk ØgaardSammendrag
On five long-term organic dairy farms aiming at self-sufficiency with nutrients, soil concentrations of ammonium-acetate lactate extractable potassium (K-AL) and acid-soluble K was measured twice in topsoil (0-20 cm) and subsoil (20-40 cm) over periods of 6-14 years. Organic management had occurred for > 9 years at the second sampling. On average there were most probably field level K-deficits. Even so, topsoil K-AL concentrations were medium high (65-155 mg K kg-1 soil), and did not decrease during the study period. However, for three farms, topsoil K-AL was approaching a minimum level determined by soil texture, where further decrease is slow. Subsoil K-AL concentrations were generally low (< 65). The soils were mostly light-textured, and reserves of K-releasing soil minerals (illite) were low, never exceeding 6% of the mineral particles < 2 mm ". Topsoil acid-soluble K concentrations were low (< 300 mg K kg-1 soil) on two farms, medium (300-800) on three farms and decreased significantly on one farm. Cation-exchange capacity increased on two farms. This may indicate increased amount of expanded clay minerals caused by K-depletion. On self-sufficient organic dairy farms, purchased nutrients will be required by low soil nutrient reserves to avoid seriously decreased yields and quality of crops.
Sammendrag
Et prosjekt som har som mål å studere for seinere å kunne minimere N-tap fra grønngjødsling er beskrevet. Prosjektet er del av et større arbeid (strategisk instituttprogram) i Planteforsk som går på økologisk korndyrking.
Forfattere
P.I. KraftSammendrag
Det er ikke registrert sammendrag
Sammendrag
Areas near the Norwegian-Russian border are being strongly contaminated by heavy metal emissions from copper-nickel smelters in the Kola peninsula. The present report presents data for the four elements arsenic, chromium, cobalt, and selenium in vegetation sampled in eastern Finmark, obtained by neutron activation analysis. It is no doubt that the smelters in Nikel and Zapolyarny, constitute the main source of these elements in this area. Some chromium comes from local domestic sources. Still, however, the concentration of these elements in soil and vegetation are probably too low as such to represent any harm to the ecosystem.
Forfattere
Espen Govasmark Turid Strøm Arvid Steen Anne Kjersti Bakken Sissel HansenSammendrag
Innholdet av et utvalg sporstoffer er analysert i planteprøver fra 28 norske økologiske husdyrbruk. Innholdet er diskutert opp mot jordforhold, artssammensetning i enga, geografisk beliggenhet og husdyras behov.
Forfattere
Mekjell MelandSammendrag
Biennial bearing is a major problem for the Norwegian apple industry. Due to over-cropping one year where fruit size and quality are reduced, the trees are likely to turn into a pattern with high and low yield every second year. This inconsistent yield pattern provides problem for both the growers and the market. Commercial practise is to remove the excessive flowers or fruitlets by chemicals or by handthinning. The only officially registered agents for apple thinning are ethephon and ammoniumthiosulphat. The growers find them unpredictable in use and more knowledge is wanted in order to give more precisely thinning recommendations. Founded by the Norwegian Research Council and The Norwegian Industrial and Regional Developments Funds, a new project started at Ullensvang Research Centre in 2003. This project will focus on optimising the crop load and test different thinning agents under bloom and at different fruitlet stages on commercial important apple cultivars. Different crop levels will be established during and after bloom by hand adjusted by trunk cross sectional area. The experimental trees will be monitored during a 3-year period. Traditional pomological observations will be registered included storage of the fruits where fruit quality will be measured. In addition the response of leaf net photosynthesis to increasing irradiance levels to determine the photosynthetic light saturation using an infrared gas analyser will be registered. Leaf areas per tree will be calculated using an area meter. Percent tree light interception in mid-season will be calculated of above-canopy incident irradiance and of light transmissions measured in a defined grid pattern below the canopy using a lightmeter. In addition different thinning chemicals will be tested according the program to the working group of European Fruit Research Institute Networks. Emphasis will be put on concentration and thinning periods of the agents ethephon, ammoniumthiosulphat and compounds that could be approved for organic growing like colza oil. Similar observations will be recorded like in the crop load study.
Forfattere
Morten Ingerslev Inge Stupak Møller Karsten Raulund-Rasmussen Ingeborg Callesen Vivian Kvist JohannsenSammendrag
Det er ikke registrert sammendrag
Sammendrag
Seven field trials were carried out on loam soil in the period 1999-2001 to assess optimum levels and timing of N application, and to obtain data on critical N% in plants. Measurements of N content were made in both harvested products and crop residues. The results showed no benefit of increasing N supply beyond 150 kg ha-1 in broccoli or white cauliflower, but 250 kg ha- 1 gave highest yield of green cauliflower (Romanesco). The latter crop had a longer growth period, and may have experienced greater leaching. Split application of N fertilizer was beneficial to all three crops, relative to giving all at planting. N recoveries declined with increasing N supply in all crops, and were lowest in green cauliflower. Split application gave only slightly increases in N recovery. Much of the N taken up by plants remained in the crop residues after harvest (normally 50-75%). In these trials the N concentration in the whole plant at harvest was, on fertilized plots, slightly higher than the critical N% for arable crops, but considerably below that which has been proposed specifically for brassica crops (Greenwood et al.1996). In other trials N concentrations measured at frequent intervals in the growing season, were seen to follow the critical N curve for arable crops when fertilizer was applied only at planting, but to be intermediate between the two critical N curves when N application was spread over a six week period. There may be some justification for recommending higher plant N levels in flowering brassicas than in leafy ones such as cabbage, but the topic requires more research. Increasing the N supply reduces its use efficiency under all conditions.
Sammendrag
Utvikling av bærekraftige produksjonssystem i landbruket sett ut frå omsyn til miljø og økonomi er eit viktig mål i landbrukspolitikken og har høg prioritet i landbruksforskinga verda over. I denne presentasjonen brukar vi resultat frå den første omløpsperioden (1990-1997) i dyrkingssystemprosjektet på Apelsvoll til å diskutere verknader av ulike dyrkingssystem og drifta av desse, på miljø, jorda sin næringsstatus, avling og økonomi, og korleis denne kunnskapen kan brukast til å utvikle eit meir bærekraftig landbruk. Alt i alt gav integrert og økologisk landbruk minst miljøskader, og med noverande subsidiar gav dyrkingssystema med forprodukson til hudyr og dei økologiske planteproduksjonssystema best økonomisk utbytte. Negativ næringsbalanse er eit alvorleg problem, som ein må ta nødvendig omsyn til i den vidare utviklinga av økologisk landbruk.
Sammendrag
I 2001 vart det funne ein ny soppsjukdom på barlind (Taxus baccata) i parken ved Norges Landbrukshøgskole (NLH). Soppen er identifisert til Cryptocline taxicola. The fungus Cryptocline taxicola was found for the first time in Norway on English yew (Taxus baccata) in 2001.