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
Forfattere
Leif Ollila Martin E Smith Steinar Wikan Paul E Aspholm Hans Geir EikenSammendrag
In recent years there have been an increaseing number of observations of brown bear in the Pasvik Valley, Northern Norway. Based on observation from general public, a study of sighting of bear close or distant human instatlation from correlated to the development of the bear population, has been carried out to reveal if there has been a shange in the brown bear appearence close to human instatlation.
Forfattere
Hugh RileySammendrag
Resultater for 1998-2004 er rapportert fra fire langvarige (25-28 år) jordarbeidingsforsøk, der konvensjonell høstpløying er sammenlignet med redusert jordarbeiding, som regel grunn harving bare om våren. Results for 1998-2004 are reported from four long-term (25-28 years) tillage trials, comparing conventional autumn ploughing with reduced tillage, normally spring harrowing only. Plant residues were retained during the period studied. The weather was somewhat wetter than the 1961-1990 normal. Results with reduced tillage were mostly similar to those seen in earlier trial periods. In Trial 1, mean grain yield was 95% with spring harrowing only versus autumn ploughing, 96% when harrowing in autumn was performed as well and 97% when the soil was ploughed every third year. In Trial 2 positive crop rotation effects were found both with and without ploughing, and reduced tillage gave 5% lower grain yield in this trial also. In Trial 3, tillage system did not affect yields of cereals grown in rotation with potatoes, but reduced tillage gave 12% lower potato yield than ploughing. Little difference in response to N fertilizer was found. In Trial 4, reduced tillage on large-scale (0.7 ha) plots gave 11% lower grain yields than annual ploughing, partly due to shallow sowing depth. No long-term trend in the yield responses to tillage was discernible in any trial, and between-year variability was similar with both ploughing and reduced tillage. Percentage yields with reduced tillage relative to annual ploughing correlated positively with rainfall in May and with mean air temperature in August. It is concluded that the reduced tillage systems studied are sustainable in terms of productivity, relative to labour, machinery and energy inputs. Likely benefits of such systems include higher levels of organic matter and aggregate stability in surface soil horizons, but a disadvantage is the need for frequent herbicide use to control perennial weeds.
Forfattere
Guro BrodalSammendrag
A survey of the loose smut frequencies in certified barley seed lots in Norway during 1997"2002 showed that the disease has become more prevalent and has occurred at higher infection frequencies in recent years. Laboratory analyses (embryo method) of barley seeds harvested in 2001 and 2002, including both certified and farm saved seed, showed a large number of infected seed lots with higher than expected infection frequencies. One lot of farm saved seed (cv. Otira) from 2002 had 32% seed infection. Unexpectedly high loose smut infection frequencies recorded in fields sown with carboxin treated barley seed suggest a reduced effectiveness of the fungicide. A seed treatment experiment was conducted in 2002 using both greenhouse and field trials with two infected seed lots (cv. Otira with 14.4% and cv. Fager with 6.9% infected seeds) to evaluate and compare the effect of Fungazil C (carboxin + imazalil) and Premis Robust (triticonazol + imazalil) against loose smut. Fungazil C at normal rates reduced loose smut frequencies by approximately 50% or less. At twice the normal rate, loose smut symptoms were reduced by 60-80%. Premis Robust showed more effective loose smut control, but did not confer complete control.
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Brita Toppe Maria HerreroSammendrag
Hovedmålsettingen for et nytt brukerstyrt prosjektet (2006-2009) er økt kvalitet og bedre produktivitet i norske prydplanter ved reduksjon i angrepet av rotsjukdommer. Prosjektet er et samarbeid mellom ulike bedrifter og forskingsinstitusjoner, og det blir gjennomført blant annet med støtte fra Norges Forskningsråd og midler over jordbruksavtalen.
Forfattere
Anne Falk ØgaardSammendrag
Det er ikke registrert sammendrag
Forfattere
Tor Håkon SivertsenSammendrag
An interpretation of the scientific principle ( as this is used in the context of agro meteorology ) is presented and discussed, containing the concepts of classification of meteorological and biological phenomena, parameterization, testing and use of models. The ideas of pure and applied science are presented, and then the concept of scope of the scientific principle is discussed. Both the use of science for understanding nature, the use of science for implementing applications, and the use of science for understanding the consequences of the use of applications are contained in this discussion. The views and discussion are also extended towards society, and what should be the content of sustainable agricultural production. The concept of the relations of human beings to othe biological organisms and to past and future generations is a part of this discussion. References: Philip, J.R, (1991), Soils, natural science, and models, Soil science. 151:91-98 Addiscott, T.M., (1993), Simulation modelling and soil behaviour, Geoderma, 60: 15-40 Sivertsen, T.H.,(2004) Invitation to Conceptual Discussions Concerning the Scope of the Scientific Method and Classification of Meteorological Phenomena and Meteorological Parameters, P 185-190, Selected Papers of the International Conference `Fluxes and Structures in Fluids", St. Petersburg, Russia, June 23-26, 2003, Moscow, IPM RAS, 2004 Sivertsen T.H., 2005, Discussing the scientific method and a documentation systems of meteorological and biological parameters, Physics and Chemistry of the Earth Special Issue: Agrometeorology 2003, Vol 30/1-3 pp 35-43 Sivertsen, T.H., 2005, Discussing scientific methods and the quality of meteorological data, in `Use and Availability of Meteorological Information from Different Sources as Input in Agrometeorological Models", COST ACTIONS 718 `Meteorological Applications for Agriculture", Edited by G. Maracchi, A. Mestre, L. Toulios and B. Gozzini. Sivertsen, T.H, 2005, ", Reflections on the Theme of Classifying, Documenting and Exchanging Meteorological Data", Atmospheric Science Letters, Vol.6 , Issue 3, p 171-175, John Wiley & Sons
Forfattere
L.H. Pardo P.H. Templer C.L. Goodale S. Duke P.M. Groffman M.B. Adams P. Boeckx J. Boggs J. Campbell B. Colman J. Compton Bridget A. Emmett Per Gundersen O. Janne Kjønaas G. Lovett M. Mack A. Magill M. Mbila M.J. Mitchell G. McGee S. McNulty Knute J. Nadelhoffer S. Ollinger D. Ross H. Rueth L. Rustad P. Schaberg S. Schiff Patrick Schleppi J. Spoelstra W. WesselSammendrag
N saturation induced by atmospheric N deposition can have serious consequences for forest health in many regions. In order to evaluate whether foliar d15N may be a robust, regional-scale measure of the onset of N saturation in forest ecosystems, we assembled a large dataset on atmospheric N deposition, foliar and root d15N and N concentration, soil C:N, mineralization and nitrification. The dataset included sites in northeastern North America, Colorado, Alaska, southern Chile and Europe. Local drivers of N cycling (net nitrification and mineralization, and forest floor and soil C:N) were more closely coupled with foliar d15N than the regional driver of N deposition. Foliar d15N increased non-linearly with nitrification:mineralization ratio and decreased with forest floor C:N. Foliar d15N was more strongly related to nitrification rates than was foliar N concentration, but concentration was more strongly correlated with N deposition. Root d15N was more tightly coupled to forest floor properties than was foliar d15N. We observed a pattern of decreasing foliar d15N values across the following species: American beech>yellow birch>sugar maple. Other factors that affected foliar d15N included species composition and climate. Relationships between foliar d15N and soil variables were stronger when analyzed on a species by species basis than when many species were lumped. European sites showed distinct patterns of lower foliar d15N, due to the importance of ammonium deposition in this region. Our results suggest that examining d15N values of foliage may improve understanding of how forests respond to the cascading effects of N deposition. Introduction Nitrogen saturation is the process by which chronically elevated N inputs alter forest ecosystems, ultimately resulting in increases in ecosystem N loss (Aber et al. 1989; 1998). N saturation can result in detrimental plant responses and have serious consequences for forest health (Nihlgard 1985; Aber et al. 1989; Schaberg et al. 2002) and may impact forests in many regions (Dise et al. 1998; Aber et al. 2003). Therefore, developing indicators useful for determining whether a forest is at N saturation and for predicting when a forest is nearing N saturation is valuable. Such indicators would facilitate both forest management and understanding of N cycling in forest ecosystems.
Forfattere
Linda H. Pardo P. H. Templer C. L. Goodale S. Duke P. M. Groffman M. B. Adams P. Boeckx J. Boggs J. Campbell B. Coleman J. Compton Bridget A Emmett Per Gundersen O. Janne Kjønaas G. Lovett M. Mack Alison Magill M. Mbila Myron J. Mitchell G. McGee Steven McNulty Knute Nadelhoffer S. Ollinger D. Ross H. Rueth Lindsey Rustad P. Schaberg Sheryl Schiff Patrick Schleppi J Spoelstra Wim WesselSammendrag
N saturation induced by atmospheric N deposition can have serious consequences for forest health in many regions. In order to evaluate whether foliar d15N may be a robust, regional-scale measure of the onset of N saturation in forest ecosystems, we assembled a large dataset on atmospheric N deposition, foliar and root d15N and N concentration, soil C:N, mineralization and nitrification. The dataset included sites in northeastern North America, Colorado, Alaska, southern Chile and Europe. Local drivers of N cycling (net nitrification and mineralization, and forest floor and soil C:N) were more closely coupled with foliar d15N than the regional driver of N deposition. Foliar d15N increased non-linearly with nitrification:mineralization ratio and decreased with forest floor C:N. Foliar d15N was more strongly related to nitrification rates than was foliar N concentration, but concentration was more strongly correlated with N deposition. Root d15N was more tightly coupled to forest floor properties than was foliar d15N. We observed a pattern of decreasing foliar d15N values across the following species: American beech>yellow birch>sugar maple. Other factors that affected foliar d15N included species composition and climate. Relationships between foliar d15N and soil variables were stronger when analyzed on a species by species basis than when many species were lumped. European sites showed distinct patterns of lower foliar d15N, due to the importance of ammonium deposition in this region. Our results suggest that examining d15N values of foliage may improve understanding of how forests respond to the cascading effects of N deposition.