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
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Dette er fyrste artikkelen i ein serie på tre artiklar om soppsjukdomar på gran. Artikkelen tek for seg rotkjuke og honningsopp på gran og eggsporesoppen Phytophthora på edelgran.
Sammendrag
Environment Synthesis) family of crop models predicts cereal growth, development, and yield. CERES simulates nitrogen (N) as a yield"limiting macronutrient. Because N leaching is an economic and environmental concern, this study evaluated if CERES can be used to predict N leaching under different N management scenarios: background leaching in unfertilized corn (Zea mays L.), alfalfa (Medicago sativa L.) residue mineralization, and till versus no"till management. Data were collected during a 7"yr field experiment on tillage practices in a maize"alfalfa"maize succession. Sensitivity analyses were performed for decomposition rates of the different residue pools and the relative proportions of carbohydrate, cellulose, and lignin in the residues. During the last 5 yr, under corn, CERES accurately simulated nitrate leaching from the no"till lysimeters. Nitrate leaching was underestimated in the tillage treatments, possibly because CERES does not simulate tillage. The model is not very sensitive to the decomposition rates and to the composition of the residues
Forfattere
Anne Kjersti Bakken Helge Bonesmo Anne LangerudSammendrag
A decision support tool predicting quality and yields in swards with timothy is described and evaluated by comparing predicted and recorded rates of phenological development, yields and yield NDF-content.
Forfattere
Anne Kjersti Bakken Olav Harbo Tor LunnanSammendrag
Timothy were grown in mixed swards with red clover and meadow fescue at three different sites under different two- and three-cut regimes in which most first cuts were taken at rather early developmental stages. Different second and third cuts were timed according to heat sum units and precisely documented according to Mean Stage by Count. The objective was to investigate how the competitiveness of timothy versus the other species was related both to the developmental stage at first cut and the timing and number of successive cuts. The responses varied between sites, and it can not be conclude that timothy never sustains harvesting regimes with early first cuts.
Forfattere
Helge Bonesmo Stein Rune Karlsen Anne Kjersti Bakken Kjell-Arild HøgdaSammendrag
Seasonal growth and minimum and maximum N content of timothy swards were calculated on the basis of soil and weather data for five sites and five years in Norway. The five sites covered a wide range of the climatic variation among regions with agricultural grass production. For each of the sites and years the daily estimated grass growth was related to the Normalized Difference Vegetation Index (NDVI) obtained from the MODIS satellite data, and on pixel-by-pixel basis threshold values of the NDVI for grass growth cessation was assessed. On the basis of the threshold values a colour map of the whole country was made, where different colours symbolized altogether four time intervals for suggested/simulated growth cessation of local timothy swards. Finally, minimum and maximum N uptake of timothy swards in the period close to growth cessation was calculated as a basis for the recommendation of local final dates of surface application of cattle slurry.
Forfattere
Anne Kjersti Bakken Helge Bonesmo Tor Lunnan Olav HarboSammendrag
With the overall aim of improving the phenological function of a decision support tool support for predictions of grass yield and fodder quality , we have tested how appropriately the scale Mean stage by count describes the continuum of phenological events in timothy. Further adaptions to the presented equations describing the functional relationships between temperature and development are suggested.
Sammendrag
Effects of composting on survival and reproduction of the potato cyst nematode (PCN) Globodera rostochiensis were investigated in 150-liter pilot scale reactors. Small bags containing cysts of PCN were incubated in organic waste and composted for 8, 15 or 29 days. Temperatures in the areas close to the cyst bags were monitored. Survival, measured by hatching, was reduced by 99.9% already after 8 days of composting and at 29 days no hatching was recorded. A few eggs, however, still hatched after being composted for 15 days and exposed to temperatures higher than 60°C for several days. Maximal temperatures and thermal exposure time as such could not explain the hatching pattern of PCN, so other factors are likely to be involved in causing lethality. PCN failed to reproduce after 8 days of composting with temperatures reaching a minimum of 50°C during the period. Hence, eight days of composting where all material have reached a temperature of minimum 50°C during the period, could be regarded as a satisfactory method for sanitation of PCN.
Forfattere
Hans Olav EggestadSammendrag
Tilskudd til endret jordarbeiding blir gjerne prioritert til arealer med høy erosjonsrisiko. Men også drensvann fra flate arealer kan være tydelig påvirket av partikler i avrenningsepiosder. Erosjon på flate arealer er imidlertid lite undersøkt i Norge. Det ble derfor satt igang et forprosjekt for å studere hvordan partikkelinnholdet i drensvann varierer med topografi (flatt og helning) og arealtilstand (stubb, pløyd, høstkorn). 18 lokaliteter i Ørje ble valgt ut og stikkprøver ble tatt under 4 nedbørepisoder høsten 2004 og 2005. Det ble funnet større innhold av partikler i drensvann fra jordarbeidet areal enn fra stubb også på flate arealer. Konsentrasjonene var imidlertid høyere fra areal med helning kontra flate arealer. På høstkornarealer er tilveksten av høstkornet avgjørende for partikkelkonsentrasjonen i drensvannet. Ved liten tilvekst var konsentrasjonene på nivå med pløyd areal, mens ved svært frodig vekst (høsten 2005) var det på nivå med stubbarealene. Det var store variasjoner og det er stor usikkerhet knyttet til slik stikkprøvetaking. For å undersøke reelle forskjeller i partikkeltap.