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.
2010
Authors
Andreas TreuAbstract
Wood modification with furfuryl alcohol is an extensively investigated process and already produced commercially. Furfurylated wood is in the focus of a European project on its use for the production of high performance windows. Different wood species were treated with furfuryl alcohol and tested on water uptake, dimensional changes, leaching in water, resistance to fungal degradation, and ecotoxicity. The results show a reduced water uptake and a reduced swelling of the furfurylated wood samples. A high resistance against fungal attack of the treated wood samples can be shown. A low amount of furfuryl alcohol was leached out and the water samples of two different leaching tests showed in general low toxicity. Southern yellow pine showed good results in all of the tests and has potential for the production of window frames according to the tests performed.
Authors
Andreas TreuAbstract
Furfurylation of wood samples can lead to different outcome (different chemistry) and product properties depending on parameters such as pH-value, catalyst, amount of water, time and temperature. Changes in the furfurylation process can even lead to a deterioration of product performance, such as lower durability in comparison to other furfurylated products. How is it possible to detect these changes in chemistry of a furfurylated wood product? To answer this question confocal laser scanning microscopy was used. The expectation was to detect different emissions of the auto fluorescent furfuryl alcohol if differences in chemistry exist. Additionally to the differences in emitted wavelength, the area in the wood structure of different emissions was under investigation. It was the aim to detect whether different product performance of a furfurylated product or different furfurylation processes could be related to changes in chemistry and this was expected to be visualized by CLSM.
Abstract
The furfurylation process is an extensively investigated wood modification process. Furfuryl alcohol molecules penetrate into the wood cell wall and polymerize in situ. This results in a permanent swelling of the wood cell walls. It is unclear whether or not chemical bonds exist between the furfuryl alcohol polymer and the wood. In the present study, five different wood species were used, both hardwoods and softwoods. They were treated with three different furfurylation procedures and leached according to three different leaching methods. The present study shows that, in general, the leachates from furfurylated wood have low toxicity. It also shows that the choice of leaching method is decisive for the outcome of the toxicity results. Earlier studies have shown that leachates from wood treated with furfuryl alcohol prepolymers have higher toxicity to Vibrio fischeri than leachates from wood treated with furfuryl alcohol monomers. This is probably attributable to differences in leaching of chemical compounds. The present study shows that this difference in the toxicity most likely cannot be attributed to maleic acid, furan, furfural, furfuryl alcohol, or 2-furoic acid. However, the difference might be caused by the two substances 5-hydroxymethylfurfural and 2,5-furandimethanol. The present study found no difference in the amount of leached furfuryl alcohol between leachates from furfurylated softwood and furfurylated hardwood species. Earlier studies have indicated differences in grafting of furfuryl alcohol to lignin. However, nothing was found in the present study that could support this. The leachates of furfurylated wood still need to be investigated further to identify the chemical differences between wood furfurylated with furfuryl alcohol monomers and furfuryl alcohol prepolymers.
Abstract
No abstract has been registered
Authors
Per Gundersen Ari Laurén Lena Finér Eva Ring Harri Koivusalo Magne Sætersdal Jan-Olov Weslien Bjarni D. Sigurdsson Lars Högbom Jukka Laine Karin HansenAbstract
Riparian forests (RF) growing along streams, rivers and lakes comprise more than 2% of the forest area in the Nordic countries (considering a 10 m wide zone from the water body). They have special ecological functions in the landscape. They receive water and nutrients from the upslope areas, are important habitats for biodiversity, have large soil carbon stores, but may emit more greenhouse gases (GHG) than the uplands. In this article, we present a review of the environmental services related to water protection, terrestrial biodiversity, carbon storage and greenhouse gas dynamics provided by RF in the Nordic countries. We discuss the benefits and trade-offs when leaving the RF as a buffer against the impacts from upland forest management, in particular the impacts of clear cutting. Forest buffers are effective in protecting water quality and aquatic life, and have positive effects on terrestrial biodiversity, particularly when broader than 40 m, whereas the effect on the greenhouse gas exchange is unclear.
Authors
Signe Nybø Gregoire Certain Olav Skarpaas Jarle W. Bjerke Erik Framstad Markus Lindholm Jan-Erik Nilsen Ann Norderhaug Eivind Oug Hans Christian Pedersen Ann Kristin Schartau Ken Olaf Storaunet Gro Ingleid van der Meeren Iulie Aslaksen Steinar Engen Per Arild GarnåsjordetAbstract
No abstract has been registered
Abstract
Dormancy release as influenced by duration of outdoor winter chilling in Florence (Italy) was studied under different photoperiodic and temperature treatments in collected twigs of two European (Ulmus glabra Huds. and Ulmus minor Mill.) and four Asian (Ulmus pumila L., Ulmus parvifolia Jacq., Ulmus macrocarpa Hance and Ulmus villosa Brandis) elm clones. Photoperiod had no effect on dormancy release, and there was no evidence that photoperiod affected bud burst during quiescence in the studied elm clones. Thermal time (day degrees >0 °C) to bud burst decreased in all the clones with increasing outdoor chilling. Although all the clones exhibited a rather weak dormancy, they significantly differed from each other. Dormancy was released earlier in the Asian than in the European clones, and the clones could be ranked from the U. pumila clone (very weak and short dormancy) to the U. minor clone (relatively stronger and longer dormancy), the other clones being intermediate. In all the clones except U. minor, the observed decrement in thermal time to bud burst was efficiently explained as an inverse exponential function of the number of chill days ≤5 °C received outdoor in autumn and winter. Endodormancy, as measured by the single-node cuttings test, was weak and short in all the clones. The latter result suggests that correlative inhibitions were largely responsible for preventing bud burst during winter in these elm clones.
Abstract
The Nordic region is characterized by simple, non-bureaucratic exchange of forest genetic resources (FGR) between countries that is strongly associated with the everyman\"s right legislation within the individual countries. The regime for international exchange of FGR is smooth and regarded as being very valuable for the forestry sector across the Nordic country borders as it secures the unrestricted availability of seeds and breeding material.
Abstract
There is great ecological, economic and social value within forest genetic resources – that is a fact. But so far, the true legal status of this resource has not been defined. This was the background for a meeting held in Vienna on 13 September 2010 which assembled forest and legal experts to discuss preliminary outputs from a NordGen project (2009-2010), initiated by representatives from Denmark, Finland, Norway and Sweden....
Abstract
Degelia cyanoloma (Schaer.) H. H. Blom & L. Lindblom is resurrected from synonymy and elevated from varietal rank to species. The taxon was earlier referred to D. plumbea (Lightf.) P. M. Jørg. & P. James, however, several discontinuous character states distinguish the two species. Degelia cyanoloma is characterized morphologically by having a large thallus that is pale greyish when dry, lobes that are composed of consecutive trough-shaped segments with an upper surface without squamules, no isidia or soredia, and apothecia discs that are dark reddish brown to blackish. Degelia cyanoloma has a euoceanic distribution and is known from western Europe (Norway, France, Great Britain, Ireland, Portugal, Spain). Based on results from studies of morphology, we hypothesize that D. atlantica (Degel.) P. M. Jørg. & P. James is the closest relative of D. cyanoloma among the European species of the genus whereas D. plumbea is closely related to D. ligulata P. M. Jørg. & P. James.