Publikasjoner
NIBIOs ansatte publiserer flere hundre vitenskapelige artikler og forskningsrapporter hvert år. Her finner du referanser og lenker til publikasjoner og andre forsknings- og formidlingsaktiviteter. Samlingen oppdateres løpende med både nytt og historisk materiale. For mer informasjon om NIBIOs publikasjoner, besøk NIBIOs bibliotek.
2008
Forfattere
Wenche E. Dramstad Frauke HofmeisterSammendrag
Det er ikke registrert sammendrag
Sammendrag
Over the last decades the forestry sciences have been opened for new topics and methods. In addition to traditional forestry topics they have participated in environmental and ecosystem research. So far this type of research has been perceived as “applied”. From the modelling perspective there has been a misunderstanding among the participating disciplines of the character of knowledge being applied. Here we introduce two types of models of forest utilization and discuss their possibilities and limits for forestry sciences. The first perspective of forests is the one dominating in modelling today and in forestry sciences. It has been adopted from physics. The second perspective of forests has implicitly been adopted in the past for pragmatic reasons.
Forfattere
Bjørn ØklandSammendrag
In recent years several forest insects have been recorded as newcomers or as more abundant than before towards northern latitudes and higher elevations in Norway. Such observations are from different groups of forest insect, including herbivorous geometrids, phloeophagous bark beetles and insects in cone seed .......
Forfattere
Peder GjerdrumSammendrag
Moisture content, volatile in nature, is an important trait for any timber customer. Commercial board samples were observed to yield formulas for EMC reduction by kiln temperature, for hysteresis by board length, and for MC sorption dynamics by temperature. Industrial kiln practice lowers the EMC to approximately 95% of tabulated values. In this work, hysteresis was verified, and the most significant impact in natural ambient is that moisture migration to the board center appears to catch up with surface adsorption, reducing the influence of temperature and surface resistance. A concluding procedure for estimating MC dynamics for timber boards on stickers is outlined.
Sammendrag
Rural communities in Norway have been under great economic stress in recent years. There has been an increasing debate about how to utilize the large potential in a growing tourism industry to promote rural employment and income. This study is based on the institutional view of innovation with a focus on institutions that are important for stimulating innovations. The objectives are: 1) to determine if networking is positively related to innovativeness and if innovativeness is positively related to performance in the nature-based tourism industry in Norway and 2) to develop an in-depth understanding of how different actors trigger a member of the industry to change, create, or otherwise innovate. An email survey was conducted of companies across the country followed by a qualitative study in one Norwegian municipality. Results indicate that there is a positive connection between networking and innovativeness, and between innovativeness and performance. A qualitative case example illustrates the interaction among actors and the resulting impacts on the innovation process.
Forfattere
Tor MykingSammendrag
An international EU/Interreg III Kolarctic project `Development and implementation of an environmental monitoring and assessment program in the joint Finnish, Norwegian and Russian border area`, was carried out during 2003–2006 as a joint undertaking between Norwegian, Finnish and Russian research institutes and environmental authorities. The aim of the terrestrial ecosystem sub-project of the Pasvik project was to develop and implement a monitoring and assessment programme for terrestrial ecosystems in the joint Finnish, Norwegian and Russian border area...
Forfattere
Peder GjerdrumSammendrag
Cost and revenue related to kiln drying are described. A calculation model compatible with a sawmill\"s profit and loss account is suggested. Typical cost items for a Scandinavian sawmill and from European litterature are reported. Cost for shrinkage/distortion/quality losses and investment/depriciation and maintenance for kilns and other technical equipment. It is claimed that better models and intensified calculation will improve sawmill profitability.
Sammendrag
In Norway, exterior wood structures have traditionally, nearly exclusively been made of untreated Norway spruce (Picea abies (L.) Karst) and pressure treated Scots pine (Pinus sylvestris L.). In recent years there has been a tendency that other wood species, like various Norwegian hardwoods or imported species, have been used in exterior above ground applications, often not surface treated. For several wood species, especially hardwoods, information regarding the durability in use class 3 is limited. Most information given in EN 350 part 2 is based on testing of the heartwood in ground contact. The test procedures for above ground test prescribed in European standards, both laboratory and field tests, have some weaknesses regarding natural durability testing. Hence, some new methods for accelerated above ground testing have been put forward. The main objectives of this project are to evaluate natural durability of Norwegian and some imported wood species for above ground applications, and to study various methods for assessing decay in wood. The project material and methods used in the project, and the results from double layer tests after one year of exposure has earlier been described, Flæte et al. (2006). This paper presents the results of the weight and MOE loss in small samples after about 3 years exposure above ground.
Forfattere
Peder Gjerdrum Olav Albert HøibøSammendrag
A huge effort has been put into modelling wood quality the last few decades. Predicting knot size has been the centre of interest, either for timber quality, for tree growth models, or related purposes. The main objective of this paper is to analyse the stochastic features connected to knot distribution inside the three-dimensional volume of a tree\"s trunk. Four large Alpine spruce trees were sampled; age 150 years, DBH 30 to 70 cm, total volume 14.5 m3. To open a possibly large part of the stems, they were cross-cut to 31 logs and sawn to 193 unedged boards. On each unique board surface all perceptible knots were observed and localised in polar coordinates; origin in the stem base, along the pith and in the north direction. A total of 6200 knot intersections were observed in the 283 m2 sawn surfaces; however, most knots were observed several times in consecutive sawn surfaces. In order to obtain stationary variable, knot size was transformed by dividing by the square root of radial distance, and radial distance was transformed by dividing by log radius at the given location. Relative size, knot quality and spatial distribution were largely random and not correlated to each other in a tree. Thus, knots demonstrate a double nature, one part obeying the physiological laws, and another part stochastic.
Forfattere
Peder Gjerdrum Mauro BernabeiSammendrag
The grain direction along an arbitrary radius is known to change at a constant rate during the life-span of a tree. A wide variety of professions involve in analysing and understanding GA, included searching new technology for automated detection and significance for wood application. The objective of the study presented in this paper has been to identify a joint, three-dimensional model for grain angle in stems of Norway spruce. Five possibly large spruce trees, DBH at least 40 cm and height ca. 30 m, were sampled near Ås, Norway. 10 cm thick transverse discs were extracted at intervals of ca 5 m along the stem, split through the pith along the north-south diameter with a blunt knife, and grain angle and cambial age observed at regular intervals of 15 mm along the north radius. Pith observation was set to zero; left-handed (clock-wise) angles were denoted as positive, and vice versa. A The grain direction along an arbitrary radius is known to change at a constant rate during the life-span of a tree. A wide variety of professions involve in analysing and understanding GA, included searching new technology for automated detection and significance for wood application...