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.
2005
Forfattere
Espen Govasmark Arvid Steen Anne Kjersti Bakken Turid Strøm Sissel Hansen Aksel Bernhoft Espen GovasmarkSammendrag
På norske økologiske husdyrgardar var innhaldet av og balansen mellom koppar, molybden og kobolt i grovfôret ikkje god nok til å møte dyra sine behov. Mineralblandingar eller kraftfor tilsett koppar og kobolt må brukast til dyra for å sikre dei ei god forsyning.
Forfattere
Govasmark, Espen Steen, Arvid Bakken, Anne Kjersti Strøm, Turid Hansen, Sissel Bernhoft, AkselSammendrag
To evaluate the animal nutritional status of copper, molybdenum and cobalt on Norwegian organic farms, soil, herbage and animal blood samples were collected from 27 dairy and sheep farms and analysed for Cu, Mo and Co. The herbage median (10th - 90th percentile) Cu,Mo, and Co concentrations (mg/kg DM) and the Cu: Mo ratio in the first cut were 5.3 (3.9 - 6.8), 1.5 (0.6 - 4.8),
Sammendrag
We investigate a data set of 160 river runoff time series at daily resolution from catchments in Southern Germany. Our aim is to seek spatial patterns for best parametrization of extreme value distributions to these data sets on one hand, and to analyze temporal instationarities of parameter estimates and extreme value attributes on the other. Conventional extreme value statistics and the calculation of return periods implicitly assume that the most extreme events are statistically independent. We demonstrate that this assumption is invalid, and that correlations, temporal as well as spatial, of arbitrary extent prevail instead. An important consequence is that the concept of return periods is obsolete. In order to find explanatory variables for the observed patterns, features of the waiting time distribution at a given relative threshold are correlated to catchment properties, such as size, mean runoff volume, elevation, and others. Finally, the effect of varying temporal resolution on the duration periods is exhibited. http://www.cosis.net/abstracts/EGU05/03192/EGU05-J-03192.pdf
Forfattere
Jon Frank Ingvald Røsberg Petter NilsenSammendrag
Project report to SNS project. Describes the methods for calculating C storage in Norwegian forests. Overview of the C-storage in forests and changes over time. Describing projects that can influence the Norwegian LULUCF reporting.
Sammendrag
In spring 2002, extensive damages were recorded in southeast Norway on nursery-grown Norway spruce seedlings that had either wintered in nursery cold storage or had been planted out in autumn 2001. The damages were characterised by leader shoot dieback and necroses on the upper or lower part of the 2001-year-shoot. Gremmeniella abietina and Phomopsis sp. were frequently isolated from the diseased seedlings. RAMS (random amplified microsatellites) profiling indicated that the G.abietina strains associated with diseased nursery seedlings belonged to LTT (large-tree type) ecotype, and inoculation tests confirmed their pathogenicity on Norway spruce. Based on sequence analysis of the internal transcribed spacer (ITS) regions of ribosomal DNA, the Phomopsis strains associated with diseased seedlings do not represent any characterized Phomopsis species associated with conifers. Phomopsis sp. was not pathogenic in inoculation tests, this implying it may be a secondary colonizer. ITS-based real-time PCR assays were developed in order to detect and quantify Gremmeniella and Phomopsis in the nursery stock. We describe here the Gremmeniella - associated shoot dieback symptoms on Norway spruce seedlings and conclude that the unusual disease outburst was related to the Gremmeniella epidemic caused by the LTT type on large pines in 2001.
Sammendrag
About eighteen percent of the conventional dairy and cash crop farmers in Norway are considering to, and four percent are planning to convert to organic farming during the next five years. These two farmer groups can be considered as the potential for conversion to organic farming in Norway. In a questionnaire survey, this group rated attitudes on organic and conventional farming more similar to organic farmers than other conventional farmers did. For farmers considering or planning to convert, additional organic farming payments, organic farming laws and regulations and price premiums for organic products were more important sources of risk than for other conventional farmers. Most of these mentioned factors are influenced by agricultural policies, which thus represent an important factor for farmers? decision regarding the conversion to organic farming.
Sammendrag
About eighteen percent of the conventional dairy and cash crop farmers in Norway are considering to, and four percent are planning to convert to organic farming during the next five years. These two farmer groups can be considered as the potential for conversion to organic farming in Norway. In a questionnaire survey, this group rated attitudes on organic and conventional farming more similar to organic farmers than other conventional farmers did. For farmers considering or planning to convert ...
Sammendrag
Adaptive traits in Picea abies (Norway spruce) progenies are influenced by the maternal temperatures during seed production. Here, we have extended these studies by testing the effects of maternal photoperiod and temperature on phenology and frost hardiness on progenies. Using eight phytotron rooms, seeds from three unrelated crosses were made in an environmental 2 x 2 factorial combination of long and short days and high and low temperatures. The progenies were then forced to cease growth rapidly at the end of the first growing season. An interactive memory effect was expressed the second growth season. Progenies from high temperature and short days, and from low temperatures and long days, started growth later in spring, ceased shoot growth later in summer, grew taller and were less frost hardy in the autumn than their full siblings from low temperatures and short days, and from high temperatures and long days. Norway spruce has developed a memory mechanism, regulating adaptive plasticity by photoperiod and temperature, which could counteract harmful effects of a rapidly changing climate.
Forfattere
Carl Gunnar Fossdal Ari M. HietalaSammendrag
The root-rot causing fungus Heterobasidion annosum can attack both spruce and pine trees and is the economically most damaging pathogen in northern European forestry. We have monitored the Heterobasidion annosum S-type (fairly recently named H. parviporum) colonization rate and expression of host chitinases and other host transcripts in Norway spruce material with differing resistances. Transcript levels of three chitinases, representing classes I, II and IV, were monitored with real-time PCR. We have also transferred a Class IV chitinase to Arabidopsis as well as its promotor in GFP and YFP reporter constructs. Ramets of two 33 -year-old clones differing in resistance were employed as host material and inoculation and wounding was performed. Multiplex real-time PCR detection of host and pathogen DNA was also performed to follow the colonization of the host tissues by the pathogen and the collapse in host DNA levels in infected regions. Host defense transcript levels, as an indicator of the host defense response, were monitored with singleplex real-time PCR. Three days after inoculation, comparable colonization levels were observed in both clones in the area immediately adjacent to inoculation. Fourteen days after infection, pathogen colonization was restricted to the area immediately adjacent to the site of inoculation for the strong clone (589), but had progressed further into the host tissue in the weak clone (409). Transcript levels of the class II and IV chitinases increased following wounding or inoculation, while the transcript level of the class Ichitinase declined following these treatments. Transcript levels of the class II and class IV chitinases were higher in areas immediately adjacent to the inoculation site in 589 than in similar sites in 409 three days after inoculation, suggesting that the clones differ in the rate of pathogen perception and host defense signal transduction. This an earlier experiments using mature spruce clones as substrate indicate that it is the speed of the host response and notmaximum amplitude of the host response that is the most crucial component in an efficient defense in Norway spruce toward pathogenic fungi such as H. annosum.
Sammendrag
Det er ikke registrert sammendrag