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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.

2011

Sammendrag

Wood protection in the last century has mainly been based on chemical treatments. Additionally, the type of construction of wooden buildings and the choice of wood species play an important role. Degradation of wood is not only caused by fungi or bacteria but also by insects. Termites have been a potential risk to wooden structures not only in the warmer regions of our continents but also beyond the regions of their natural habitat due to transport of wood. A new treatment, Electro osmotic pulsing technology (PLEOT), has been tested in lab termite tests and fungi tests. The two choice and non-choice termite tests were carried out using different duration of exposure and different initial wood moisture content. The results show growth of mould fungi on untreated wood samples with high initial wood moisture content after 4 weeks of termite testing whereas PLEOT treatment strongly reduced the development of moulds. Termite mortality was high on untreated wood samples with high initial moisture content but not on wood samples with low initial moisture content. This is explained by mould growth on the wetter samples, which termites don\"t tolerate in large amounts. The loss of wood mass due to termite attack could be reduced by using PLEOT. The mortality of termites was higher in test systems with protected wood samples than untreated samples. PLEOT could be used successfully against fungal attack. The treatment reduced on the one hand mould growth in a termite test and on the other hand reduced strongly the attack of brown rot fungi in a lab test.

Til dokument

Sammendrag

A combined wood impregnation process including impregnation with a chromium-free wood preservative and oil treatment was evaluated with regard to leaching of copper during the oil process. Two different experimental setups make up the balance of copper content in oil, wood samples and condensate water, also taking different fixation times and process durations into account. Copper is sufficiently fixed after 24 hours, and leaching of copper into the oil is low. Increasing the oil process time does not lead to increased leaching. The hot oil treatment of impregnated wood under vacuum atmosphere is a fast drying method without major negative consequences for the impregnated copper.

Sammendrag

Timber constructions are often built in combination with other materials such as concrete. These materials can influence the timber construction. Moist concrete can e.g. lead to development of molds which creates an unhealthy living area for people. Furthermore, moisture in wood buildings can negatively affect the wood material, which can lead to negative biological activity in timber and possible reduction of strength properties of timber constructions. The present paper introduces a new innovative method of timber protection and describes the influence of moisture on wood and concrete. The new environmental friendly system for protection of timber has been tested on wood destroying fungi and termites. It can be shown that wood protection by means of electro osmotic pulsing technology can preserve wood in laboratory trials. The wood moisture content is reduced when the protection system is installed. Trials on protected wood against subterranean termites showed lower wood moisture content after test of protected samples compared to untreated samples. However, termite activity could not be reduced to a larger extend as the termite living surroundings were not included. It could be shown that humidity in pores of concrete in cellar walls is reduced using electro osmotic pulsing. The drying of concrete when combined with timber constructions can additionally help to reduce timber degradation as all protection measures that lead to a drier building are positive for fungi and subterranean termite control.

Sammendrag

A new protection system has been tested which protects wood without treating it - by installing a low pulsing electric field. This electro-osmotic pulsing technology on wood, called PLEOT, has been tested in lab trials. Wood has a low specific conductivity and is considered as a dielectric material. Water plays therefore an important role. With increasing wood moisture content, a favorable environment for fungi development is created. At the same time, increasing wood moisture content increases the conductivity in wood and PLEOT can protect the material. Wood can be considered as naturally protected against fungal attack at a wood moisture content <20 %. It could be shown in lab tests, that a protection by means of PLEOT can be achieved at higher wood moisture content....

Sammendrag

Frøplantasjefrø av gran blir stadig mer pupulært og utgjør nå 75% av skogen som plantes i Sørøst-Norge. Enkelte steder er andelen opp i 90%. Dette bidrar til økt overlevelse og en markert produksjonsforbedring av skogen i forhold til bestandsfrø. Men hva vet vi om den genetiske variasjonen i plantasjefrø, som produseres under helt andre betingelser enn frø i vanlige bestand?

Sammendrag

1. Surrogate species measures of biodiversity (SSB) are used worldwide in conservation prioritisations. We address the important question whether the ideas behind SSB are consistent with current knowledge on distribution patterns of species, as reflected in theories of community assembly. 2. We investigated whether assumptions necessary for successful functioning of SSB (nested species assemblages, cross-taxon congruence, spatio-temporal consistency) were supported by predictions from either niche or neutral community models. 3. We found a general mismatch between ideas behind SSB and ecological community theory, except that SSB based on complementarity may be consistent with niche-based theory when gradients in species composition are strong. 4.  Synthesis and applications. The lack of a necessary scientific foundation may explain the disappointing results of empirical tests of SSB. We argue that site selection should be based on costs and opportunities within complementary environmental/land units, rather than expensive inventories of unfounded surrogate species.