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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.

2012

Abstract

Phytosociological studies can be an important tool to detect temporal vegetation changes in response to global climate change. In this study, we present the results of a resurvey of a plot-based phytosociological study from Sikkilsdalen, central Norway, originally executed between 1922 and 1932. By using a detailed phytosociological study we are able to investigate several aspects of elevational shifts in species ranges. Here we tested for upward and downward shifts in observed upper and lower distribution limits of species, as well as changes in species optima along an elevational gradient, and related the observed range shifts to species traits that could explain the observed trends. More species shifted upwards than downwards, independently of whether we were investigating shifts in species\" upper or lower distribution ranges or in species optima. However, shifts in species upper range margins changed independently of their lower range margins. Linking different species traits to the magnitude of shifts we found that species with a higher preference for prolonged snow cover shifted upwards more in their upper elevational limits and in their optima than species that prefer a shorter snow cover, whereas no species traits were correlated with the magnitude of changes in lower limits. The observed change in species ranges concord both with studies on other mountains in the region and with studies from other alpine areas. Furthermore, our study indicates that different factors are influencing species ranges at the upper and lower range limits. Increased precipitation rates and increased temperatures are considered the most important factors for the observed changes, probably mainly through altering the pattern in snow cover dynamics in the area.

Abstract

The objective of the project Winfur (within WoodWisdomNet) was the industrial application of furfurylated wood in the window market. Because of promising results concerning the wood species European beech, common ash, radiata pine and Southern yellow pine it was decided to evaluate material from these species.The material exhibits promising wood water related behaviour. Coating tests showed the coatability with selected commercial products. Additionally, outdoor weathering tests were performed. It is also possible to produce 3-layer scantlings with common gluing systems like PVAc. The resistance against wood destroying fungi increased in a way that the material is suitable for the window application. Different investigations were performed to test the furfurylated material and the results are satisfying.The last step in the project was the production of prototypes for different investigations. The window companies reported no differences between using furfurylated wood compared to untreated wood within the production of the windows. The tests of full scale window prototypes according to seven test standards, e.g. repeated opening and closing and water tightness against driving rain were performed.The production and standardised testing of full-scale window prototypes indicates that the use of furfurylated wood will not cause any problems with fulfilling the criteria for the Scandinavian P-mark and the German RAL certificate. The overall conclusion is that furfurylated wood material is suitable for the window production.

Abstract

Damage by cone and seed insects is a severe impediment to those producing conifer seeds in seed orchards. The SNS-supported network `Nordic cone and seed insects` has been cooperating to address this problem since 2007. One of the outcomes is the coordinated monitoring of the most important insect species. The data collected form a basis for establishing strategies for pest management.

Abstract

Brown-rot fungi such as Postia placenta are common inhabitants of forest ecosystems and brown rot fungi are also largely responsible for the destructive decay of wooden structures. The aim of this study was to compare two commonly used strains of Postia placenta MAD-698-R and FPRL 280. Scots pine sapwood samples were exposed for two and eight weeks to both fungal strains. The following was investigated: mass loss, fungal gDNA content and gene expression.A significant difference was found in mass loss after eight weeks between the P. placenta strains MAD-698-R and FPRL 280. MAD-698-R gave higher mass loss than FPRL 280. However, MAD-698-R seems to have a slightly slower growth rate than FPRL 280, reflected in lower gDNA content after two weeks.After eight weeks of exposure the gDNA content dropped and no significant difference was found between MAD-698-R and FPRL 280. We observed differences in mass loss, colonization-rate and gene expression between the two Postia strains. Results suggest significant differences in the regulation of key lignocellulose degrading enzymes between MAD-698-R and FPRL 280.