Publications
NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.
2002
Abstract
Patrolling with livestock guard dogs in mountain rangelands in Norway was evaluated as a method to prevent predation in areas with widely dispersed sheep. In contrast to the traditional use of guard dogs, patrol dogs are closer socially bonded to people and follow a range inspector around. Range inspection was performed in 5 h bouts during three nights per week. The method was tested during three summer seasons in a total of eight sheep flocks grazing in three different mountain ranges. In total, three inspectors and four dogs were involved. Significant reductions in the number of sheep lost were achieved in one of the study areas. Lack of significance in the other areas were mainly due to the size of the area and qualities of the dogs: the range to be patrolled by one man/dog unit should not exceeed 10-12 km2, and the dogs should be experienced guard dogs, which are properly socialized for this method.
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Authors
Leif Jarle Asheim Lars Olav Eik Ivar MysterudAbstract
No abstract has been registered
Authors
David Wei Zheng M. Freeman J. Bergh Ingvald Røsberg Petter NilsenAbstract
A process-based model was used to simulate biomass production of Norway spruce under both current climate and climate change scenarios. The model was parameterized for Nordmoen in south-east Norway using real climate data for the period 1987-1989. The model was applied to predict the biomass production responses to three climate change scenarios.The results showed that net primary production (NPP) increased by 7% under an elevated annual mean air temperature of 4C from the current 10.1 t dry mass ha-1 yr-1. A doubled current ambient CO2 concentration significantly increased NPP by 36%.The scenario of both elevated temperature and elevated CO2 concentration led to an increase in the NPP of 49%, higher than the sum of the two effects acting singly. The results also showed that forest production responses to climate change depend on the conditions of climate used for reference.
Abstract
The project reported here was a co-operation between the National Focal Centers for four of the ICPs in Norway: ICP Mapping and Modeling, ICP Waters, ICP Forest and ICP Integrated Monitoring. Dynamic modeling was carried out using data from several sites in the ICP networks, with the aim of making predictions on the future acidification status for surface waters, forest and soils in Norway. Predictions are made for three different deposition scenarios. At two of the sites, the model predictions suggest that the Current Legislation scenario will not promote water qualities sufficient for sustainable fish populations, while the scenario seems sufficient for the others. Under the Maximum Feasible Reduction scenario one of the sites still will not reach a sufficiently high ANC. In general, the modeling results for forest soils agree with results from previous investigations stating that surface water acidification is more severe than the soil acidification. However, the results suggest that there has been soil acidification at all sites as a result of acid deposition and that the base saturation will not be built up again to pre-industrial levels during the next 50 years at any of the sites, not even with the Maximum Feasible Reduction Scenario.
Authors
Harald Kvaalen Ola Gram Dæhlen Ulrika EgertsdotterAbstract
No abstract has been registered
Abstract
No abstract has been registered
Academic – Quality seed – a factor for sustainable progress
JG Hampton, NM de Carvalho, M Kruse, ...
Abstract
No abstract has been registered
Abstract
Determining the level of pathogenic fungi and other microorganisms during colonization of the host is central in phytopathological studies. A direct way is to monitor fungal hyphae by microscopic examination, but indirect chitin and ergosterol-based assays have been among the most applied methods in determining fungal biomass within host tissues. Recently real-time technology is increasingly receiving attention as a way to follow infection agents in host tissues.We study the molecular basis of host defense responses, using the coniferous host Norway spruce (Picea abies) infected with the basidomycete Heterobasidion annosum as the experimental system. This basidiomycete is the major root rot causing pathogens in conifers of all age classes.In order to screen host material for differential resistance towards H.annosum for both scientific and commercial reasons, it is a necessity to reliably quantify the fungal colonization of the host tissues. Therefore, the aim of this study was to develop and compare the sensitivity of a real-time PCR assay to an ergosterol based method for determining the rate of colonization by H.annosum in inoculated spruce material. We also applied the methods to rank the infection level of the pathogen on the spruce tissue culture clones.We were able to develop a quantitative multiplex real-time PCR procedure that reliably detecting down to 1pg H.annosum DNA and 1ng host DNA in DNA extracted from infected tissues. There was a very high correlation between the fungal-biomass/total-biomass and fungal DNA-total DNA rankings obtained with ergosterol and real-time PCR respectively, strengthening the credibility of both methods.Based on both ergosterol and real-time PCR, it was clear that some spruce clones were faster and more heavily infected than others. These results indicate that both ergosterol and this real-time procedure can be useful methods to screen different spruce material for their relative resistance to the pathogen H.annosum.