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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.

2009

Abstract

In forestry, it is important to be able to accurately determine the volume of timber in a harvesting site and the products that could potentially be produced from that timber. We describe new terrestrial scanning technology that can produce a greater volume of higher quality data about individual trees. We show, however, that scanner data still often produces an incomplete profile of the individual trees. We describe Cabar, a case-based reasoning system that can interpolate missing sections in the scanner data and extrapolate to the upper reaches of the tree. Central to Cabar’s operation is a new asymmetric distance function, which we define in the paper. We report some preliminary experimental results that compare Cabar with a traditional approach used in Ireland. The results indicate that Cabar has the potential to better predict the market value of the products.

Abstract

A catchment provides ecosystem data along with (relatively) simple, operationally defined boundaries. In addition runoff is an integrated measure of the hydrochemical ecosystem response, which can be represented by fluxes at the weir. Integration at the weir occurs first of all with respect to spatial scales. Almost all fluid output leaves a (tight) catchment at this point. Evaluation of the runoff dynamics (quantity and quality) is primarily concerned with temporal scales. The Lange Bramke catchment study with its four runoff series from forested catchments (spring and weir at Lange Bramke, weirs at Dicke Bramke and Steile Bramke) provides an exceptionally comprehensive data set. The following scales and processes can be considered, when interpreting temporal variations in runoff data: above the time scale of forest rotation (species composition, biomass accumulation, timber export, soil nutrient pools) at decadal time scales up to a full forest rotation of about 100-120 years (changes in forest growth rate, changes in deposition, climate change, insect outbreaks) at annual time scales (uptake, transpiration) at hourly to weekly time scales of hydrological events (precipitation, runoff, dilution effects of solvents).

Abstract

Long-term monitoring meteorological, hydrological and hydrochemical data from small catchments are irreplaceable witnesses of past environmental conditions. This insight shaped the formation of the Long-Term Ecological Research Network (LTER) in the US, but European as well as German siblings are under preparation. Among the European forested monitoring sites, the Bramke catchments in the Harz mountains present a particularly well-documented case, with daily runoff measurements starting after World War II-related reparation cuts in 1948, and surface water chemistry being observed since the 1970ies. Originally powered by research on erosion, then by acid rain research and the then-prominent “forest decline”, a large set of hydrochemical variables (major ions) is available now with basically weekly resolution. Previously tightly connected to academic research at the University of Göttingen, routine measurements are by now performed by local forest authorities, ensuring forthcoming continuity even when public attention should shift away again from climate change research.

Abstract

This paper examines the relationship between external relations and innovation in small, knowledge-intensive Norwegian firms. Our findings indicate that external relations are beneficial for innovation. The analysis shows that it is necessary to treat innovation as more than a concept. Our independent variables related differently to product innovation, process innovation, and market innovation. We found that market participation in product development has a positive impact on product, process and market innovation. We also found that top management interaction with other firms had a positive effect on market innovation and that top management interaction with external R&D had a positive effect on product innovation. This finding probably indicates that access to R&D resources is vital for product development in the context of knowledge-intensive products. The results also show that participation in conferences and courses positively influences process and market innovation and that systematic environmental scanning positively influences product innovation.

Abstract

Wood is a traditional building material but in general it underlies restrictions in outdoor applications due to its respective durability against microbiological decay. To face this problem, different impregnation systems are applied to enhance the materials\" servicelife. Scots pine (Pinus sylvestris) is the most widely distributed pine in Eurasia and hence easily available. Despite of the previously defined good treatability of Scots pine sapwood, large differences in treatment performance are reported from industry. As process parameters are always adjusted to the material most difficult to treat, permeability variations in wood material are an economical problem. Therefore, it is important to understand the material in order to make a more reasonable material selection possible.....

Abstract

The durability of wood in exterior use is limited by to climatic factors and wood deteriorating organisms. The natural durability of the Nordic wood species is generally regarded as low, and for e.g. decking and use in soil contact wood protection is needed. Within the last years, new non-biocidal treatments, like wood modification systems, have been developed to improve the biological resistance of wood. For information about the decay resistance of untreated and modified wood, natural outside exposure is necessary. European standard EN 252 is the main field test method for use class 4. In use class 3 the need of new or improved test setups has been put forward. Traditionally evaluation of field trials has mainly been based on visual evaluation and pick-test. However, to get in depth knowledge about: 1) different field trial methods and 2) fungal colonization of new wood protection systems, additional assessment methods can be used. Hence, comparative studies are needed.....

Abstract

Information given in EN 350-2 on natural durability of different wood species against wood destroying fungi is mainly based on heartwood tested in ground contact. The objective of this study was to test and compare durability of many different wood species in a field test in ground contact. The material consisted of Norwegian wood species able to give sufficient sawn wood dimensions (commercial and less utilised species, indigenous and introduced species) and imported species (Larch from Russia; Oak, Douglas fir and Western Red Cedar from North America; Merbau and Teak from Asia). Additionally, modified wood (thermally modified and tall oil treated) and preservative treated wood (CCA- and Cu-preservative) were included in the test. The wood types, 31 in total, were tested according to EN 252 and EN 350-1 at NTIs test site in Sørkedalen, Norway. Results after five years exposure show that most of the Norwegian grown wood species have low durability. This study also provides information on durability of four species not included in EN 350-2: Juniperus communis, Salix caprea, Sorbus aucuparia and Populus tremula.

Abstract

One of the biggest drawbacks of using European native wood species as a construction material is its tendency to degrade by fungal attack. This has lead to the development of different systems for wood preservation. Many of these systems suffer the disadvantage that they contain biocides, which can leach from the wood into the environment and damage organisms. In this project ten silanes, 3-(2-Aminoethylamino)propyltrimethoxysilane, 3-[2-(2- aminoethylamino)ethylamino]propyltrimethoxysilane, 3-Aminopropyltrimethoxysilane, Diethoxydimethylsilane, Dodecyltriethoxysilane, Hexadecyltrimethoxysilane, NTrimethoxysilylpropyl- N,N,N-trimethylammoniumchloride, Octyltriethoxysilane, Octyltrimethoxysilane and Phenyltrimethoxysilane, have been investigated for their ability to increase the hydrophobicity of wood and decrease shrinking and swelling, and thus increase its ability to withstand attack by fungi. In the initial phase of the project two solvents, ethanol and water were investigated to find out which of these that gave the best result for surface modification with silanes. The results showed that water as solvent gave a surface with higher hydrofobicity than when ethanol was used as solvent....

Abstract

A range of studies the last decade has shown that modified wood can provide excellent protection against a range of wood deteriorating organisms, including decay fungi. However, we still lack information about why the modified wood is protected from microbial attack. An understanding of the mechanisms utilized by decay fungi when exposed to modified wood is important for further optimisation of new modified wood products. Several hypotheses have been put forward, but they still need testing. The aim of this study was to summarize our earlier studies using molecular methods as a tool for better understanding of the mode of action of decay fungi in furfurylated wood. The studies include laboratory and field evaluations of decay colonisation patterns and gene expression....