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.
1999
Forfattere
Maria Herrero Sonja KlemsdalSammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Populærvitenskapelig – Igangsatte pyntegrønt-prosjekter på 1990 tallet
Tormod Stavrum, Jan-Ole Skage
Forfattere
Tormod Stavrum Jan-Ole SkageSammendrag
De fleste produsenter av juletrær og klippegrønt har fra tid til annen hørt og lest om forskjellige prosjekter med relevans til næringen som er igangsatt, eller ønskes igangsatt.Fra enkelte hold er det kommet ønske om at det gis en mest mulig samlet oversikt over det som gjøres og har blitt gjort. I det følgende vil en derfor forsøke å gi en statusrapport for de prosjektene som har et nasjonalt preg
Forfattere
Erik Trømborg Joseph Buongiorno Birger SolbergSammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Espen Haugland R.J Froud-WilliamsSammendrag
1. In order to investigate the factors influencing the establishment of seedlings in permanent grassland, the influence of soil moisture and nitrogen fertilisation on competition between established Lolium perenne and seedlings of Phleum pratense or Trifolium pratense was studied in two experiments under greenhouse conditions using the `split-box"-technique. 2. There was no difference in the production of plant dry matter of P. pratense or T. pratense between 30 % volumetric soil water content (-0.005 MPa) and 22 % (-0.04 MPa), but 15 % soil moisture (-0.33 MPa) reduced plant growth. L. perenne yields were linearly reduced by reduced soil moisture content. 3. Shoot competition from L. perenne reduced the plant dry matter yield of P. pratense and T. pratense more than did root competition in these experiments. When shoot competition was present, differences between moisture contents were not detected, indicating that light was probably the limiting resource under such conditions. No significant interaction between root competition and soil moisture were observed for plant weight. 4. Root competition was not prevented even though sufficient water and nitrogen were supplied. This indicated either that some other growth factor was limiting or the plants competed for resources at the root hair level even though sufficient resources were supplied at the pot or field scale. Therefore, in the situation of direct drilling of species during grassland renovation, it may be difficult to alleviate competition by adequate provision of water and nitrogen.
Forfattere
O. Janne KjønaasSammendrag
Det er ikke registrert sammendrag
Forfattere
O. Janne KjønaasSammendrag
Mixed bed ion exchange resin bags have previously been used in studies of soil N transformation rates with NH4-N and NO3-N being adsorbed from the solution percolating through the incubated soil core. An evaluation of the in situ adsorption efficiency of mixed bed resin bags was performed by comparing dissolved inorganic nitrogen (DIN, sum of NH4-N NO3-N) accumulated in resins with DIN fluxes in throughfall (TF) and with DIN concentrations in soil water. A significant correlation was found between DIN fluxes in TF and accumulated DIN in resins placed at the soil surface (r2= 0.92 for NO3-N, r2=0.86 for NH4-N, p0.001). The ratio of accumulated DIN in resins to DIN flux in TF was significantly affected by season. A low but significant correlation was found between NO3-N concentrations in soil water and NO3-N contents in resins deployed in the bottom of soil cylinders (r2=0.34, p0.01), however, when only the winter periods were taken into account, the correlation improved (r2=0.72, p0.001). As little water and few nutrients are removed from the soil water by the vegetation during the dormant season, the conditions inside and outside the core were more comparable. For NH4-N there was no correlation between accumulated amounts in the resins and concentrations in soil water sampled at 13 cm and 20 cm depth, respectively, probably due to the strong depth gradient in the NH4-N concentrations of the soil. Although the resin bags were unable to adsorb all the incoming DIN, they gave valuable information on small scale input of N and small scale differences in NO3-N leaching.
Forfattere
A. FriesSammendrag
Det er ikke registrert sammendrag
Forfattere
Kari Anne Sølvernes Gunnar OgnerSammendrag
The impact of climate change on a mini forest ecosystem was studied for three years in an open-top chamber (OTC) experiment with an outside control plot. Clones of Silver birch (Betula pendula Roth.) and Norway spruce (Picea abies (L.) Karst) were grown in monolithic lysimeters containing undisturbed profiles of podsolic forest soil. The original understory was also present.The soil temperature was increased with 2-3 C. The atmospheric CO2 concentration in the OTCs was ambient (380mol mol-1 CO2), approximately 500 and 700 mol mol-1 CO2. The leachates from the lysimeters was collected, and the solute concentration was analysed monthly.Increased soil temperature increased the mineralisation of soil organic matter, and large amounts of nitrate, dissolved organic nitrogen (DON) and aluminium were released. In the leachates from the 500 mol mol-1 CO2 birch lysimeters, high concentrations of Al were recorded during the second and third growth seasons.The high concentrations of Al were correlated with high concentration of total organic carbon (TOC) and increased pH. Large amounts of Al was organically bound in these leachates. The origin of the organic ligands could have been products of the birch roots, e.g. root exudates.