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.
2001
Authors
Peder Gjerdrum M. Warensjö M. NylinderAbstract
Log sorting according to dimension and quality is the first important step during conversion from sawlog to sawn timber. Crooked logs should be rejected or sawn to reduced yield. The 3D scanner furnish detailed information about the log geometry.Based on cylindrical co-ordinates four new parameters describing the centroid were evaluated: Maximum Radial Deviation (MRD), Standard deviation of the Sweep Angle (SSA), Distance from Log End to MRD (DLE), and Residual between the Radial deviation and a skew sinusoidal Model (RRM). 56 unbarked spruce logs were sampled, representing six different crook types denoted I, J, C, V, Z and S according to their curvature.Algorithms were established by means of logistic regression models to distinguish between several crook classes. It was concluded that the 3D scanner can be programmed to effectively perform automatic crook detection and classification.
– Natural organic matter in the nordic countries
Rolf D. Vogt, E.T. Gjessing, Dag Olav Andersen, ...
Authors
Rolf D. Vogt E.T. Gjessing Dag Olav Andersen Nicholas Clarke T.C. Gadmar K. Bishop U.S. Lundström Michael StarrAbstract
In the Total Organic Carbon (TOC) intercalibration sub-project a set of 10 synthetic and natural samples as well as non-labile reverse osmosis isolates were sent to 25 laboratories for the analysis of TOC and dissolved Organic Carbon (DOC).The outcome of the statistical treatment of the results from this intercalibration and the information regarding the participants instruments and standard operational procedures is that:Synthetic samples provide apparent better precision than natural samples. This fact, together with the good experience from the use of non-labile Reverse Osmosis (RO) and freeze dried isolates of dissolved organic carbon (DOM) in the intercalibration, lead us to recommend the use of RO isolates as material for the preparation of house standards and for determination of methods merits.The intra laboratory precision (relative standard deviation) varied from 5 to 16%.The fractionation of the DOC by 0.45um membrane filtering causes in some cases a contamination of carbon to the sample.A specific construction in a brand of the TOC analysers give poor results in samples with high TOC concentrations and that are of refractory material. The five selected sampling sites have proven, on the basis of their soil and water chemistry, to be well suited for studying the effect of climate and S-deposition on the characteristics of DOM. 163 water samples from two seasons (fall and spring) and 20 soil samples are collected and analysed.Most water samples are determined for all major charge contributing species, DOM fractions, and several other parameters. The DOM in the surface waters have been isolated both using reverse osmosis and hydrophobic resin (XAD8). The original surface water, reconstructed water by RO isolates as well as the XAD8 fractionated DOM have been characterized by a number of methods ranging from optical properties to pH and metal titration.The RO isolates have been provided to 14 scientific research groups in Europe and North America that are in the process of using their analytical technique to characterize the DOM.The soils have been determined for key explanatory variables as pH, cation exchange capacity and C/N ratio. The main findings from the characterisation of DOM is that:Generally the hydrophobic acid fraction (HPO-A) was the main DOM fractions in all water compartments and sites.Seasonal variation in the DOM fractionation is found to be greater than the variation between the sites and water compartments. The DOM fractionation is therefore not a fingerprint of the site.According to a batch titration experiment the aluminium complexing ability of the HPO-A and hydrophilics (HPI) DOM fractions (fractionated using only the XAD8 resin) was indistinguishable.The HPI fraction has generally a higher site density of weak acids (WA).The reverse osmosis (RO) isolates represent the total DOM in the original sample.NMR spectres of the RO isolates show that the main difference between the sites lie in the amounts of carbohydrates and aromatic compounds.The RO isolates produce reconstructed water with DOM that have similar optical properties.PCA analysis suggest that as the S-deposition is decreasing we should expect relatively more hydrophobic character of the DOM.The spring sample from Svartberget differs from the rest of the samples in that there was a small rainstorm causing a hydrologic episode during the sampling. This led to the lowest pH, highest TOC and organic charge (A-) among the surface water samples. In terms of DOM characteristics this temporal variation in flow regime led to the highest HPO-N DOM fractions, lowest intensity of the NMR spectre and low ash content and lower density of WA then expected. This expresses the importance of temporal variation during hydrologic episodes.
Authors
Carl Gunnar Fossdal Lars Sandved Dalen Jørgen A. Mølmann John Beck JensenAbstract
To find interesting gene products and to study gene expression in the green parts of Norway spruce we have sequenced 1101 cDNA clones based on mRNA isolated from needles. Here we present some preliminary findings describing the frequency of different Expressed Sequence Tags (ESTs), the ratio of similarity to known and unknown sequences present in GenBank and sequences not previously reported from Norway spruce. In addition we have tried to place the ESTs into major categories based on putative function
Authors
John Beck Jensen Jørgen A. Mølmann Jorunn Elisabeth Olsen Lars Sandved Dalen Olavi Junttila Øystein Johnsen Anders Lönneborg Carl Gunnar FossdalAbstract
To find interesting gene products and to study gene expression in the greenparts of Norway spruce we have sequenced 1101 cDNA clones based on mRNA isolated from needles. Here we present some preliminary findings describing the frequency of different Expressed Sequence Tags (ESTs), the ratio of similarity to known and unknown sequences present in GenBank and sequences not previously reported from Norway spruce. In addition we have tried to place the ESTs into major categories based on putative function
Abstract
Epiphytic lichen vegetation on birch stems was studied in the border areas between Norway and Russia. The area is heavily influenced by sulphur dioxide pollution emitted from Russian nickel smelters.Hypogymnia physodes and Melanelia olivacea were the two most abundant lichen species on birch stems in the investigated area. However, the coverage of H. physodes and M. olivacea was clearly reduced in parts of the investigated area. The lichen vegetation increased with increasing distance from the pollution source, i.e. from a lichen desert to normal background levels. A different pattern of occurrence of the two lichen species was observed.
Authors
Gunnar Ogner Guro Randem Torild WickstrømAbstract
Analyses of forest soils are widely used to monitor the effects of human activity on our environment. The overall quality of analytical data must, therefore, be sufficient to answer questions with regard to environmental changes taking place throughout several decades.Three horizons of an air-dried forest soil, was stored at 22 3 C, 3 C and 21 C for up to 1842 d to monitor its stability during storage. At room temperature, soil acidity increased and soil pH in water decreased by 0.1 to 0.3 pH units depending upon the soil horizon.The amount of C, P, and S extracted by 1M ammonium nitrate increased by 94%, 62% and 68%, respectively, after 1842 d. A corresponding increase in exchangeable cations [aluminium(Al), barium(Ba), calcium (Ca), magnesium (Mg), manganese (Mn), strontium (Sr), and zinc (Zn)] ranged from 11 to 23%. Storage at 3 C resulted in a decrease in pH only for mineral soil (10-15 cm layer). At 21 C, no changes in any of the soil-extractable components were found.
Abstract
No abstract has been registered
Authors
Malin Elfstrand Carl Gunnar Fossdal Gunilla Swedjemark David Clapham Olof Olsson Folke Sitbon Praveen Sharma Anders Lönneborg Sara von ArnoldAbstract
In this study we have investigated whether the defensin-like gene spi 1, isolated from Norway spruce, contributes to quantitative disease resistance and is a suitable candidate for utilisation in Norway spruce breeding programmes. The following questions have been raised: (1) Can the putative defense gene, spi 1, improve the defense towards microbial pathogens in a model plant species, tobacco? (2) Is it possible to produce transgenic plants of Norway spruce that overexpress spi 1 and are less susceptible to the pathogenic fungus Heterobasidion annosum? Compared to control plants, tobacco plants expressing spi 1 under an enhanced CaMV 35S promoter permitted less growth of the bacterial pathogen Erwinia carotovora. Embryogenic cultures of Norway spruce were transformed with a similar construct. The general phenotype of regenerated transgenic plants was normal, although it was difficult to maintain certain sublines in culture owing to poor initial growth. Among the transformed plants those with the highest content of SPI 1 displayed reduced fungal growth in the sapwood after inoculation with H. annosum. In conclusion, the spi 1 gene increases resistance in both homologous and heterologous systems.
Authors
Birger VenneslandAbstract
The connection between rural economic development policy and forest policy in Norway during the past decades is discussed. Because of this connection it is debatable whether it is reasonable to maintain a strong focus on timber supply in Norwegian forest policy in the future. By analyzing studies related to forestry in the context of rural development, the lack of combined rural development research and forestry research is shown. It is argued that rural policy/research and forest policy/research should be combined in the future regarding topics related to forestry in the field of rural development.
Authors
Isabella BørjaAbstract
No abstract has been registered