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.
2008
Authors
Sebastian EiterAbstract
Anmeldt bok: Price, Martin F. editor, 2007. Mountain area research and management: integrated approaches. Earthscan, Sterling, Virginia. xiv + 302 p. $95.00, ISBN: 978-1-84407-427-3.
Authors
Kerry O'Donnell Todd J. Ward Dereje Aberra H. Corby Kistler Takayuki Aoki Nathane Orwig Makoto Kimura Åsmund Bjørnstad Sonja KlemsdalAbstract
No abstract has been registered
Authors
Tove Maria Østensvik Petter Nilsen Kaj Bo VeierstedAbstract
The goal of this cross-sectional study was to investigate the impact of different physical work station designs, expressed in two different brands of forest vehicles, on the muscle activity patterns in the neck and upper extremities among the vehicle operators. Surface electromyography (sEMG) was continuously recorded bilaterally on the trapezius (TM) and the extensor digitorum muscles (EDM) during one working day among operators driving Timberjack and Valmet vehicles, either as harvesters (n = 7 and 6, respectively) or forwarders (n = 9 and 9, respectively). Both the construction of the crane in relation to the chassis and the design of the control levers vary between the Tim-berjack and Valmet vehicles, which demand different ergonomic performance by the operators. The operators mostly handle control levers in the harvesters or forwarders, the latter with a more varied work load, in a fixed, seated working posture in the cabin for long hours with little rest. The sustained low- level muscle activity was quantified by periods with muscle activity above 0.5 percent EMGmax into 10 predetermined duration intervals from 1.6 to 5 s up to above 20 min (SULMA periods). These SULMA periods were analyzed both for number in the different intervals and cumulated periods above the predefined values. Amplitude and frequency parameters were analyzed and the number and total duration of muscle rest periods were calculated. The operators driving Valmet harvesters had a significantly higher number of long cumulated SULMA periods above 10 min in the left TM, and showed a higher level of static muscle activity and less total duration of muscle rest in TM bilaterally. The operators driving Timberjack forwarders had a significantly higher number of SULMA periods between 10 and 20 min in the right TM. No difference was found between the operators in the EDM activity pattern. The results of our study showed that operators driving Valmet harvesters had more sustained low-level activity in the neck than those driving Timberjack, including a higher number of long cumulated SULMA periods, higher static level, and less muscle rest. Despite a small sample, the results in muscle activity pattern raise the question of needs for improvements of the forest vehicle workstation design.
Abstract
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.
Abstract
Three unsprayed coffee farms (farm 1, 2 and 3) were studied for the natural occurrence of the insect pathogenic fungus Beauveria bassiana in Hypothenemus hampei populations throughout the rainy season of 2004 (July-November) and 2005 (July-December). B. bassiana infections were found during most sampling dates in both years, on all three farms. The B. bassiana infection levels were higher in 2005 than in 2004 with mean prevalence of 12.1 % and 2.7%, respectively. No consistent significant differences in infection level between farms were found in any of the years. B. bassiana infection levels fluctuated widely throughout the season, and peaked at 13.5% on farm 3 in 2004 and at 44.0% on farm 1 in 2005. The H. hampei population was significantly higher in 2004 than in 2005, with 6.9% of the berries infested in 2004 and only 0.7% in 2005. In both years, the H. hampei infestation level was significantly higher on farm 2. No consistent significant differences in H. hampei infestation levels were found between sampling dates on any of the farms. H. hampei infestation levels fluctuated throughout both seasons, and peaked at 15.3% on farm 2 in 2004 and 2.2% on farm 2 in 2005. No consistent density dependent correlation between H. hampei infestation level and B. bassiana infection level was found. Correlations between climatic conditions and R bassiana or H. hampei were not found. (C) 2007 Elsevier Inc. All rights reserved.
Authors
Erlend Ystrøm Haartveit Per Otto FlæteAbstract
Wood from different tree species is commonly similar in visual appearance but still have considerable differences in machining and wood properties. Even heartwood and sapwood from the same tree species may be difficult to separate visually, but the wood properties important for the quality of the final products may differ. Hence, within the forest products industry there is a great need to non-destructively evaluate wood quality prior to and during manufacturing in order to ensure effective allocation of raw material, and to obtain consistent and well defined quality of the end products. Near infrared spectroscopy is a promising technique because it requires minimal, if any, sample preparation and provides results rapidly, even when used on intact, opaque biological samples. In this paper we use near infrared spectroscopy combined with multivariate statistical analyses for classification of wood types. Case I considers heartwood and sapwood from Scots pine. On freshly cut wood heartwood and sapwood are visually similar, but the wood properties differ. Case II considers wood from tree different species of spruce, Norway spruce, Sitka spruce and Lutz spruce. The species have differences mechanical and machining properties. NIR spectra were recorded directly on solid wood surfaces. The multivariate statistical analyses were based on partial least squares methodology and resulted in successful classification of wood types in both cases. All models were validated using test set validation. In both cases the result showed that near infrared spectroscopy and multivariate statistics can be used to develop well-performing prediction models for classification of visually similar wood types.
Abstract
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 e-mail 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.
Abstract
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.
Abstract
Studies regarding the environmental impact of engineered nanoparticles (ENPs) are hampered by the lack of tools to localize and quantify ENPs in water, sediments, soils, and organisms. Neutron activation of mineral ENPs offers the possibility of labeling ENPs in a way that avoids surface modification and permits both localization and quantification within a matrix or an organism. Time-course experiments in vivo also may be conducted with small organisms to study metabolism and exposure, two aspects currently lacking in ecotoxicological knowledge about ENPs. The present report explains some of the prerequisites and advantages of neutron activation as a tool for studying ENPs in environmental samples and ecologically relevant organisms, and it demonstrates the suitability of neutron activation for Ag, Co/Co3O4, and CeO2 nanoparticles. In a preliminary experiment with the earthworm Eisenia fetida, the dietary uptake and excretion of a Co nanopowder (average particle size, 4 nm; surface area, 59 m(2)/g) were studied. Cobalt ENPs were taken up to a high extent during 7 d of exposure (concentration ratios of 0.16-0.20 relative to the ENP concentration in horse manure) and were largely retained within the worms for a period of eight weeks, with less than 20% of absorbed ENPs being excreted. Following dissection of the worms, Co-60 was detected in spermatogenic cells, cocoons, and blood using scintillation counting and autoradiography. The experimental opportunities that neutron activation of ENPs offer are discussed.
Abstract
The European pine sawfly Neodiprion sertifer is a widely distributed defoliator of pines that can cause substantial growth losses over extensive areas. It attacks most species of twoneedle pines in its distribution area, and have occasional short-lived outbreaks that may cover up to 200.000 ha. In Norway we have had outbreak populations in the eastern part of the country since 2004, and in an ongoing research project we are evaluating aerial application of the Neodiprion sertifer nuclear polyhedrosis virus (NsNPV) to control Neodiprion sertifer....