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.
2010
Sammendrag
Measurements of heat production rate have been made on wood samples with the brown rot fungus Postia placenta at different moisture contents. The results clearly indicate that the heat production rate (a measure of respiration rate and activity) is moisture dependent. When the moisture content is decreased, less heat is produced, and when the moisture content is increased, more heat is produced. Isothermal calorimetry seems to be a measurement technique well suited to the study of rot fungal activity as a function of temperature and moisture content.
Sammendrag
One of the main challenges for new wood protection systems is to predict in a fast and accurate way service life in use class 3 (above ground) and use class 4 (in soil or fresh water contact). New environmentally benign wood protection systems are expected to have different modes of action against wood deteriorating fungi compared to the traditional preservatives, change in water sorption being one of them. Therefore it is of importance to evaluate new treated wood products in a broad range of exposure situations, also exploring the variation within use class 3 and 4. Due to the restrictions in the use of chromium containing wood preservatives, a range of studies have been published the last decade evaluating the performance of new products after laboratory or field test exposure. However, there is still a lack of studies comparing the same material in different field exposure situations. This study evaluates the efficacy of 13 novel wood protecting systems in three different above ground tests (horizontal double layer, block test and mini stakes) and two different in-ground tests (EN 252 and mini stakes). Scots pine (Pinus sylvestris L.) sapwood from the same wood source was used for all treatments. For each wood protecting system the wood specimens for all five tests were treated together in the same batch. The results after five years of field exposure are presented. In the three above ground tests no or only initial signs of decay were detected after five years (not reaching a mean rating of 1). The decay rate in soil contact was faster than above ground, but after five years only untreated wood (controls) failed in both tests. No significant difference in performance was found between the two tests in soil contact. The use of median decay rate values gave an earlier indication of performance than the use of mean decay rate values.
Sammendrag
Modified wood can provide protection against a range of wood deteriorating organisms. But we still lack information about why the modified wood is protected from microbial attack. Several hypotheses have been put forward for the mode of action against wood decaying fungi, including inhibition of action of specific enzymes, but they still need further testing. In this study gene expression of the brown rot fungus Postia placenta FPRL 280 has been monitored after 2, 4 and 8 weeks of colonization in furfurylated Scots pine (Pinus sylvestris L.) and in untreated control samples. Preliminary results are given. The main finding was that genes related to oxidative metabolic activity generally was higher in furfurylated wood compared to untreated Scots pine. Carbohydrate metabolism related expression varied. For one endo-glucanase and two β-glucosidases the expression was lower in furfurylated wood compared to untreated control, while for one glucoamylase and one glucan 1,3b glucosidase the expression was higher in furfurylated wood. The four cytochrome P450 tested, involved in breakdown of toxic compounds, gave inconsistent results between furfurylated and untreated control samples. Phenylalanine ammonia lyase and cytosolic oxaloacetase gave higher expression in control than in furfurylated samples.
Sammendrag
During the first few weeks of life, chicks of the capercaillie (Tetra urogallus) and black grouse (T. tetrix) subsist mainly on insects, of which lepidopteran and hymenopteran larvae are the main components. We studied the breeding phenology of these two species and examined how the timing of breeding was related to the temporal distribution of their larval food source. During a five-year survey, capercaillie mated and hatched consistently four to six days before black grouse. Depending on the vegetation type, the number of larvae (>= 2 mm in length) increased between five and ten times within 10 days, and hatching coincided roughly with the peaks in larval numbers. Due to body growth, however, larval abundance in terms of volume was reached later and occurred 8-9 and 13-14 days after the mean hatching dates in the two species, respectively. Slightly later development of Hymenoptera as compared with that of Lepidoptera contributed in extending the period of high larval abundances for more than one week. The timing of breeding of the two species appears, therefore, to match the temporal distribution of insect food for the fast-growing chicks as they hatch several days before the peak in larval volumes. In one year, when mating was advanced, presumably due to exceptionally warm weather before mating (yet the temporal abundance of larvae was unchanged), breeding success was higher than in years when mating occurred later.
Forfattere
Gunnhild SøgaardSammendrag
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Sammendrag
Det internasjonale biomangfoldåret er på hell. Norge har, i likhet med flere andre land, satt 2010 som frist for å ”stoppe tapet av det biologiske mangfoldet”. Som en del av dette arbeidet fikk Norge i 2009 ny Naturmangfoldlov (Lov om forvaltning av naturens mangfold). I §23 i loven heter det at ”Kongen i statsråd kan ved forskrift utpeke nærmere angitte arter som prioritert.” Dette åpner for særskilte tiltak, og skal være et virkemiddel for å ta vare på arter som har problemer med å overleve. Men hvilke av de rundt 40.000 naturlig forekommende arter av dyr, planter og sopp i Norge skal prioriteres, og hvilke kriterier skal legges til grunn for utvelgelsen av disse artene?
Sammendrag
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Forfattere
Erling MeisingsetSammendrag
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