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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.

2018

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Earlywood samples of unmodified and acetylated radiata pine were exposed to the brown-rot fungus Rhodonia placenta for 1, 2, 3 and 4 weeks for unmodified samples and 10, 16, 24 and 28 weeks for acetylated samples. Longer incubation periods were used for acetylated samples based on the hypothesis that given enough time under favourable conditions the fungus would eventually degrade the wood. After exposure, samples were weighed and chemically characterized by ATR-FTIR analysis, acetyl content by saponification, and hydroxyl (OH) accessibility by deuterium exchange. Longer incubation times for acetylated samples led to comparable levels of mass loss between unmodified and acetylated wood. Initial brown-rot decay in acetylated wood exhibited a different trend compared to unmodified wood, with an increased OH accessibility and a significant reduction in acetyl content. This was followed by a stable, low OH accessibility and plateau in acetyl content above 10% mass loss in acetylated wood. In unmodified wood, the OH accessibility was nearly constant throughout decay, while the initially low acetyl content decreased linearly with mass loss. ATR-FTIR analysis confirmed the differences in acetyl removal between unmodified and acetylated wood. Wood-water relations before and after brown-rot decay were determined with low-field nuclear magnetic resonance (LFNMR) relaxometry on water saturated samples. For the decayed acetylated wood, the behaviour of the water corresponded well with de-acetylation observed by chemical characterization. The results show that after removal of acetyl groups, degradation of acetylated wood by R. placenta occurred at a similar rate to that of unmodified wood.

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Aim:Macroecological scales of species compositional trends are well documentedfor a variety of plant and animal groups, but remain sparse for fungi, despite theirecological importance in carbon and nutrient cycling. It is, thus, essential to under-stand the composition of fungal assemblages across broad geographical scales andthe underlying drivers. Our overall aim was to describe these patterns for fungiacross two nutritional modes (saprotrophic and ectomycorrhizal). Furthermore, weaimed to elucidate the temporal component of fruiting patterns and to relate theseto soil carbon and nitrogen deposition. Location:Central and Northern Europe.Methods:A total of 4.9 million fungal fruit body observations throughout Europe,collected between 1970 and 2010, were analysed to determine the two main envi-ronmental and geographical gradients structuring fungal assemblages for two mainnutritional modes, saprotrophic and ectomycorrhizal fungi. Results:Two main gradients explaining the geography of compositional patternswere identified, for each nutritional mode. Mean annual temperature (and relatedcollinear, seasonal measures) correlated most strongly with the first gradient forboth nutritional modes. Soil organic carbon was the highest correlate of the second compositional gradient for ectomycorrhizal fungi, suspected as an indicator of vege-tation- and pH-related covariates. In contrast, nitrogen deposition constituted asecond gradient for saprotrophic fungi, likely a proxy for anthropogenic pollution.Compositional gradients and environmental conditions correlated similarly whenthe data were divided into two time intervals of 1970–1990 and 1991–2010.Evidence of compositional temporal change was highest with increasing elevationand latitude. Main conclusions:Fungal assemblage patterns demonstrate clear biogeographicalpatterns that relate the nutritional modes to their main environmental correlates oftemperature, soil organic carbon and nitrogen deposition. With respect to globalchange impacts, the highest rates of compositional change by time suggest targetinghigher latitudes and elevations for a better understanding of fungal dynamics. We,finally, suggest further examination of the ranges and dispersal abilities of fungi tobetter assess responses to global change.