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.
2003
Authors
Harald Kvaalen Ola Gram Dæhlen Ulrika EgertsdotterAbstract
No abstract has been registered
Authors
Erlend Ystrøm Haartveit Dag FjeldAbstract
Efforts to improve efficiencies in the forest industries have mainly focused on problems within the borders of the company. Thus, there is an unexploited potential for increased efficiency through integrating and coordinating activities between companies. This poster presents games that mimic the forest industry and demonstrate to...
2002
Authors
Harald Kvaalen Ola Gram DæhlenAbstract
No abstract has been registered
Authors
Kjell Andreassen Bernt-Håvard ØyenAbstract
Six experimental sites in the coastal spruce (Picea abies L. Karst.) forest of central Norway were investigated. A comparison of different silviculture systems was performed based on the present situation of mature stands, and a single tree selection system, a group system and a clearcutting system were studied. The diameter distribution shows the classical inverse J-shaped curve at five of six sites. The mean tree volume removed in the selection system was 0.6 m3, and about 0.3 m3 for the other two methods. The harvesting cost was about 14 Euro/m3 for clearcutting, and about 10% higher for the group and selection systems. In simulations of all future revenues and expenses based on the observed stand conditions, cutting and extraction costs, the net present value (NPV) was app. 15% lower for the group and selection systems compared to clearcutting. A lower stem volume production in uneven-aged stands and higher administration and harvesting costs had only a minor influence on the NPV. One percent higher interest rate lowered the NPV of the group and selection systems to 75% of the clearcutting method.
Authors
Erlend Ystrøm Haartveit Dag FjeldAbstract
Two games, called “Wood Supply Games”, are developed based on the structure and dynamics of the Beer Game. The games are intended as student exercises in forestry logistics courses. By introducing divergent and convergent flows in the supply chain, the relevance to the forest sector is increased. Results from pilot experiments of the games are presented and discussed in terms of how different degrees of complexity in supply chain structures may affect their efficiency. Measures of efficiency are accumulated costs, amplification of demand and the sample variance of order rates. Results indicate that supply chain performance is negatively affected by increasing rigidity of constraints at points of divergence. Furthermore, lower degrees of efficiency and predictability are observed as complexity of supply chain structure increases. Testing of results and proposed hypotheses can be accomplished by running numerous replications of the games, or alternatively, by development of appropriate simulation models.
Authors
Harald Kvaalen Ola Gram Dæhlen Ulrika EgertsdotterAbstract
No abstract has been registered
2000
Authors
M.J. Latkowska Harald Kvaalen M. AppelgrenAbstract
The influence of light quality on the proliferation of embryogenic tissue of three genotypes of Norway spruce (Picea abies [L.] Karst), with different capacities for mature somatic embryo production, was studied.The proliferating tissues were subjected to light from commercially available light sources: Philips TLD Warm White 36W/29, Philips TLD Blue 18W/18, Philips TLD Red 36W/15, Osram L Fluora 36W/77 and Sylvania Far Red 7080, for 18 h a day with the photon flux (PAR) at 30 mol m-2 s-1.The effect of light quality on the growth of embryogenic tissue was strongly genotype dependent. In genotype 164-4 tissue proliferation was strongly inhibited by blue and red light. Genotype 86:52 reacted in a similar way, but not as strongly as 164-4, whereas the tissue of genotype 186-3 was almost insensitive to light quality and grew fast in all light conditions.
Authors
Erlend Ystrøm Haartveit Dag FjeldAbstract
Structural changes in the sawmilling industry imply more wood transport as distance between sawmills is increasing. One of the factors that determines the potential for economies of scale is the trade-off between reduced production costs and increased transport costs. The methods used in this study are based on geometric properties of wood procurement areas.The effects of the distribution of forest (area coefficient) and the road net (winding coefficient) upon average transport distance was explored, and considerable regional variation was found.The transport net factor (t) is the product of the area coefficient (a) and the winding coefficient (w) and gives a relative measure of the potential for efficient procurement logistics with respect to the distribution of productive forest area and the road net. The transport net factor is estimated for two wood procurement areas in each of four regions.When studying the sawlogs procurement in regions with different density of sawlogs buyers, average transport distance increases relatively more in areas where several buyers are competing for a limited timber supply than in areas with few competitors.
1999
Authors
C. Walter L.J. Grace S.S. Donaldson J. Moody J.E. Gemmell S. van der Maas Harald Kvaalen Anders LönneborgAbstract
An efficient Biolistic transformation technology was developed to stably transform Picea abies (L.) Karst. Several embryogenic tissue lines were tested for proliferation on standard embryogenesis media. Transient transformation studies with these lines were performed to optimize the parameters for genetic transformation. Selection conditions for transgenic tissue based on the nptII resistance gene in combination with the antibiotic geneticin were defined such that only transgenic P. abies lines were able to develop. Nontransgenic tissue was completely inhibited under these conditions. Stable integration of a uidA reporter gene and a nptII resistance gene into the genome of P. abies was achieved and more than 200 mature embryos were regenerated for every transformation event. Histochemical and fluorometric analysis indicated strong expression of the uidA gene in transgenic material. ELISA studies to detect and quantify the nptII gene product as well as polymerase chain reaction and Southern blotting confirmed the presence and integration of uidA and nptII genes into the P. abies genome. Transgenic P. abies plants from nine independent transformation events were recovered and are currently growing in a greenhouse for genetically modified organisms, awaiting field release.
Authors
M.J. Latkowska Harald Kvaalen M. AppelgrenAbstract
No abstract has been registered