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.
2015
Authors
Mark Hughes Callum Aidan Stephen Hill Alexander PfriemAbstract
The mechanical properties of thermally modified wood are discussed with regard to toughness. The molecular origins of the mechanical properties and, in particular, the role of the hemicelluloses are considered. The important role of water and its interaction with the cell wall components is also examined. The properties are discussed from the point of view of composite theory, with the three main macromolecular components acting as reinforcement, matrix and interfacial coupling agent. The important role that hemicelluloses play as a coupling agent between the cellulosic microfibril reinforcement and the lignin-rich matrix is highlighted. Destruction of the hemicelluloses during the thermal modification process has a profound effect upon the mechanical behaviour.
Authors
Magdalena Broda Bartłomiej Mazela Katarzyna Królikowska-Pataraja Callum Aidan Stephen HillAbstract
The archaeological wooden oak piles of medieval "Poznan" bridge, situated at the bottom of Lednica Lake in Greater Poland, are a valuable relic of the beginnings of the Polish country. The assessment of the state of wood preservation will allow to propose the most appropriate conservation agents and methods in order to save this cultural heritage. The aim of the study was to evaluate the degree of degradation of waterlogged piles by using traditional and non-destructive testing methods and to estimate the usefulness of non-destructive FT-IR and computed tomography techniques in such an assessment. The applied traditional, destructive methods, like chemical and physical, as well as non-destructive ones, like X-ray CT or FT-IR, showed that the archaeological oak wood elements are quite well preserved, especially their heartwood part. The obtained results clearly confirm that the modern X-ray CT measurement and FT-IR analysis can be very useful in archaeological wood research, giving a good insight into wood structure.
Authors
Hans Ragnar NorliAbstract
No abstract has been registered
Authors
Lise GrøvaAbstract
No abstract has been registered
Authors
Lise GrøvaAbstract
No abstract has been registered
Authors
Dag Fjeld Bruce TalbotAbstract
No abstract has been registered
Abstract
Ten saplings of European ash (Fraxinus excelsior L.) naturally infected by the invasive ash dieback pathogen Hymenoscyphus fraxineus were collected in Ukraine and Norway and examined for bark necrosis and extension of discoloration in sapwood and pith in a stem region. Tissue-specific colonization profiles were determined by spatial analyses of symptomatic and visually healthy stem tissues using a H. fraxineus-specific qPCR assay and light microscopy. Our data suggest that hyphal growth in the starch-rich perimedullary pith is of particular importance for both axial and radial spread of H. fraxineus, but that most of its biomass accumulates in sapwood parenchyma. The study confirms the results from earlier work and presents new information that refines the current stem invasion model.
Abstract
Predicting how human induced vegetation changes affect ecosystems and their biological communities is one of the most urgent tasks in ecology. In Norwegian lowlands one of the main threats to biodiversity is abandonment of low intensive land-use areas. Effects of changed land-use on vegetation are generally made by assessing the effect on the number of species as indicators of biodiversity. However, community structure changes and ecosystem processes are not necessarily well described by this biodiversity indicator only. Functional trait responses might better predict structures and processes than species richness. Therefore, studies of functional traits and biodiversity indexes of these might provide deeper insight. In addition, to predict reliable future vegetation changes, multifactorial determinants have to be considered as vegetation is not driven by one determinant only.
Authors
Anette Tjomsland SpillingAbstract
Researchers will genetically modify tobacco plants to produce enzymes that can break down biomass from forest raw materials. This may lead to a more effective, economic and sustainable production of biofuels.
Authors
Susan E. Chen Anke Möser Rodolfo M. Jr. NaygaAbstract
No abstract has been registered