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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.

2008

Abstract

Combined bark beetle-fungus attacks are a key factor in conifer ecosystems in the Northern Hemisphere, where they regularly cause massive tree mortality. Central to the success of the bark beetle-fungus complex is the fact that bark beetles are among the few insects that are capable of breaching the potent anatomical and chemical defenses of healthy tree stems.....

Abstract

In this study, the effect of two boric acid concentrations (1% and 2%) and four derivates of tall oil with varying chemical composition were tested separately and in combination. The tall oil derivates were chosen in a way that they consist of different amounts of free fatty, resin acids and neutral compounds. Decay tests using two brown rot fungi (Postia placenta and Coniophora puteana) were performed on both unleached and leached test samples. Boric acid showed a low weight loss in test samples when exposed to fungal decay before leaching, but no effect after leaching...

Abstract

Wood for outdoor decking has a high marked share in the Nordic and Baltic countries among private house owners. Important issues for the consumer are maintenance intervals and aesthetic appearance as well as decay resistance. Knowledge and consumer information about these aspects are required to ensure that wood can compete with alternative decking materials. In this paper an accelerated testing of decking, “stapelbäddsmetoden”, was evaluated after six years of exposure at Ås, Norway, and compared with earlier reported results after three years. Twelve different preservatives and wood modification treatments were used in addition to untreated Scots pine (sapwood and heartwood) and larch (heartwood). The samples were treated with two different surface treatments. In addition there was one set without any surface treatment. In this method for accelerated testing, discolouration and decay was evaluated. This provided new information about performance both on and above ground for a range of different combinations of preservative/modified systems and surface treatments of wood in decking for outdoor use. For example, no clear differences were found between the surface treatments and no surface treatment. The wood modifications with styrene and furfurylalcohol performed just as good, or better, than the copper containing treatments.

Abstract

Over the last decades the forestry sciences have been opened for new topics and methods. In addition to traditional forestry topics they have participated in environmental and ecosystem research. So far this type of research has been perceived as “applied”. From the modelling perspective there has been a misunderstanding among the participating disciplines of the character of knowledge being applied. Here we introduce two types of models of forest utilization and discuss their possibilities and limits for forestry sciences. The first perspective of forests is the one dominating in modelling today and in forestry sciences. It has been adopted from physics. The second perspective of forests has implicitly been adopted in the past for pragmatic reasons.

Abstract

Possible differences in gross and net feed balance and feed efficiency between two cattle breeds were studied. The “old” Black Sided Trønderfe and Nordlandsfe (STN) breed has hardly been selected for production traits the last decades due to a small population (800) while and the modern Norwegian Red (NR) breed (230 000) has been bred according to a modern breeding programme with genetic improvements in milk, growth, health and fertility. The study was done on lactating cows in three indoor feeding periods; ten cows in each breed group, fed roughage ad-lib and an adjusted level of concentrates. Feed intake, milk yield and -quality were recorded every week, and live weight was recorded every month. The gross energy balance was defined as energy intake subtracted by energy in produced milk, while the gross energy efficiency was computed by dividing energy in produced milk by energy intake. At the net energy level it was adjusted for energy loss or release from body tissue gain or loss. The results show that in spite of the large difference in production level, there were no breed differences in energy balance, neither at the gross nor at the net level. However, the NR was significantly more efficient when comparing gross feed efficiency, but there were no breed differences in net feed efficiency.