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
No abstract has been registered
Authors
Svein Solberg Andreas Brunner Kjersti Holt Hanssen Holger Lange Erik Næsset Miina Rautiainen Pauline StenbergAbstract
In this study we demonstrate how airborne laser scanning (ALS) can be applied to map effective leaf area index (LAI(e)) in a spruce forest, after being calibrated with ground based measurements. In 2003 and 2005, ALS data and field estimates of LAI(e) were acquired in a Norway spruce forest in SE Norway. We used LI-COR's LAI-2000 (R) Plant canopy analyzer ("LAI-2000") and hemispherical images ("HI") for field based estimates of LAI(e). ALS penetration rate calculated from first echoes and from first and last echoes was strongly related to field estimates of LAI(e). We fitted regression models of LAI(e) against the log-transformed inverse of the ALS penetration rate, and in accordance with the Beer-Lambert law this produced a linear, no-intercept relationship. This was particularly the case for the LAI-2000, having R-2 values > 0.9. The strongest relationship was obtained by selecting ALS data from within a circle around each plot with a radius of 0.75 times the tree height. We found a slight difference in the relationship for the two years, which can be attributed to the differences in the ALS acquisition settings. The relationship was valid across four age classes of trees representing different stages of stand development, except in one case with newly regenerated stands which most likely was an artifact. Using LAI(e) based on HI data produced weaker relationships with the ALS data. This was the case even when we simulated LAI-2000 measurements based on the HI data. (C) 2009 Elsevier Inc. All rights reserved.
Authors
Peder GjerdrumAbstract
This report is an output from the Northern Periphery Programme project “Developing the Scots Pine Resource”. The overall aim of this project is to stimulate the development and optimal utilisation of the Scots pine resource as a basis for sustainable, competitive, small- and micro-scale rural industries. Describing and analysing existing markets is part of this task, and the objective of this report. The report covers the Scots pine roundwood trade in the northern parts of Scotland, Norway, Sweden and Finland, the area covered by the InterReg Northern Periphery Programme (NPP, www.northernperiphery.eu). It consists of four papers, one for each country, which have been prepared by the relevant project partners. Together they give a thorough overview of the Scots pine timber trade in north-west Europe.
Abstract
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
Erlend Ystrøm Haartveit Leif Kjøstelsen Egil Roar RavnemyhrAbstract
Measuring logistics costs for individual products or product groups is a significant challenge. One frequently applied method is Activity Based Costing approach where costs are allocated to products according to the resources and cost they induce. The Norwegian project Woodflow has been working on measuring time consumption for logistics processes for wood products such as lumber, beams, claddings, panels and moulds. Low degree of standardisation within and between manufacturers makes it problematic to convert time and performance measures from one unit of measurement to others. Logistics costs are difficult to allocate to products and are in commonly presented for the complete material flow. The existing data could not be used for calculation of logistics costs for wood products. Different methods have been used to measure time and resources for the processes in the supply chain. Even if the process is correctly measured, it is still be a challenge to allocate costs to products, for example when a carrier contains a large number of different products. The performance measures presented have been developed for Optimera AS, a vertically integrated distributor of construction products. The company owns several distribution centres and more than 70 stores in Norway. A test of the measurements will be conducted in a small part of the distribution system. The logistics costs of supplying the stores from the distribution centre will be compared with directly transporting the lumber from the supplier to the retail outlets.
Authors
Vibeke Lind Jan Berg Lars Olav Eik Jørgen A.B. Mølmann Espen Haugland Marit Jørgensen Margrethe HerslethAbstract
Many consumers perceive lamb meat from mountain pastures to be of superior quality, a quality that may be altered if lambs are kept for a longer period on cultivated pastures before slaughtering. The objective of this experiment was to compare sensory profile and fatty acid composition in meat from lambs slaughtered directly from unimproved mountain pastures with meat from lambs raised on unimproved mountain pastures and fattened on biodiverse cultivated pastures for 26, 39 and 42 days before slaughtering. The experiment was conducted at two different locations in Norway in 2006 and 2007, with a total of 124 Norwegian Crossbred Sheep lambs. Loin samples of M. Longissimus dorsi from lambs above a body weight of 40 kg were selected and analysed for sensory attributes. Fatty acid composition was determined in the subcutaneous fat over the Longissimus dorsi. Small but significant differences were found in hardness, tenderness, fattiness, metallic and rancid flavour, and in polyunsaturated fatty acids. This indicates that to a small extent pre-slaughter fattening on cultivated pastures alters meat characteristics. (C) 2009 Elsevier Ltd. All rights reserved.
Abstract
In this study we aimed at understanding the mechanisms that affects an epidemic development of Neozygites floridana in a Tetranychus urticae population. This was done by comparing how many spores a cadaver infected with a N. floridana isolate could produce and at what distance and in which directions they could be thrown on a coverslip at temperatures relevant to the northern hemisphere (13, 18 and 23oC). The highest number of spores were produced at 13oC at a number of 1886. Numbers of spores thrown at 18oC and 23oC were 1733 and 1302 respectively. Temperature had a significant effect on sporulation. Most of the spores were thrown at a distance of 0-0.6 mm from the cadaver. Cadavers placed on the underside of a coverslip were able to throw spores back up on the coverslip surface. A whole plant bioassay was also conducted to reveal where on a plant T. urticae infected with N. floridana die and sporulate. Cadavers showed a different verical distribution on the cucumber plant compared to healthy spider mites. Most of the cadavers were located at the lower to the middle part of the plant, while healthy spider mites were more evenly distributed on the whole plant.
Authors
Kristine Solberg Rolf David Vogt Odd EilertsenAbstract
No abstract has been registered
Authors
Igor A. Yakovlev Harald Kvaalen Carl Gunnar Fossdal Øystein JohnsenAbstract
MicroRNAs (miRNAs) are endogenous small RNAs that can have large-scale regulatory effect and could participate in epigenetic regulation of gene expression in plants. We show for the first time that temperature during zygotic embryogenesis and seed maturation in Norway spruce regulates an “epigenetic memory” in the progeny, regenerated through somatic embryogenesis. The warmer the in vitro temperature applied, the later the regenerated plants formed terminal buds in the common environment the second growth season. The differences were very large, and similar in size to a provenance separation of 4 – 6 degrees of latitude (Kvaalen and Johnsen, 2008). To study a molecular mechanisms of a memory from embryo development we have prepared two concatemerized small RNA libraries representing small RNAs predominantly expressed in plants growing from seeds obtained after embryogenesis in cold environment (CEL) and warm environment (WEL) after short day (SD) treatment (going to bud set). In total we obtained 201 different small RNAs, with dominated length of 21-nt, 123 from WEL and 93 from CEL. Using multiple methods, including BLAST, sequence alignment and sequence folding we found 27 novel candidate miRNAs and only 3 earlier described. Additionally 103 small RNAs have exact matches in spruce EST database, which could be their putative targets and 67 small RNAs have no matches. We used quantitative RT–PCR to study the expression patterns of 31 chosen candidate miRNAs and monitor the occurrence stage-dependent miRNA-mediated cleavage for 4 regions of putative mRNA targets. All miRNA show difference in transcript levels after SD treatment and 12 miRNAs show constitutively differential expression in progeny from CE and WE. Kvaalen H, Johnsen O (2008) Timing of bud set in Picea abies is regulated by a memory of temperature during zygotic and somatic embryogenesis. New Phytologist 177: 49-59
Authors
Jarl-Gunnar Salin Peder GjerdrumAbstract
Wooden poles are frequently used for power and telecommunication lines. After creosote preservation the durability is secured for many decades. This study is related to a Norwegian plant where such poles are produced using Scots pine. Prior to the preservation process the poles have to be dried to a moisture content below the fibre saturation point everywhere in the pole. This is done outdoors in open stacks of poles, i.e. as air-drying. A problem is caused by the difficulties to determine when the target moisture content has been reached. The inventory of drying poles represents considerable value in a company\"s balance sheet and risk of downgrading. Knowledge of drying times during the annual seasons has been insufficient, and no efficient method is known for accurately observing the MC through the various parts of the poles.....