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
Jørund Aasetre Vegard GundersenAbstract
Almost 80 % of Norwegians live in urban areas, making urban forests highly valuable. The multitude of values assigned to those forests creates conceptual challenges, especially incorporating humanistic and existentialistic views of man. The aim of this presentation is to propose a value taxonomy for urban forests that takes such views of man into consideration, and to suggest how this can be useful to managers. Methodologically the taxonomy is developed through a literature review of environmental philosophical and recreation management literature, and then tested through qualitative interviews with selected stakeholder groups in urban forests near Trondheim, Bergen and Oslo. Through the literature review demand values, instrumental values and constitutive values were identified as key categories. Demand values are utilitarian values appreciated for their own sake, while instrumental values are valued as means to get other values. Such concepts are used in philosophy by Ariansen (1997) and psychology by Rokeach (1973). Constitutive values are genuine non-utility values contributing to our deep felt self understanding, often subdivided into ethical, cultural identity and religious – spiritual values. Introducing constitutive values may help avoiding the trap of the `commodity metaphor` in the often utilitarian oriented management literature...
Authors
Mari Mette Tollefsrud Roy Kissling Felix Gugerli Øystein Johnsen Tore Skrøppa Rachid Cheddadi W.O. van der Knaap Magorzata Lataowa Ruth Terhürne-Berson Thomas Litt Thomas Geburek Christian Brochmann Christoph SperisenAbstract
Norway spruce (Picea abies [L.] Karst.) is a broadly distributed European conifer tree whose history has been intensively studied by means of fossil records to infer the location of full-glacial refugia and the main routes of postglacial colonization. Here we use recently compiled fossil pollen data as a template to examine how past demographic events have influenced its modern genetic diversity...
Abstract
No abstract has been registered
Abstract
New restrictions draw governments, industry and research towards new and environmental benign wood protective agents. These agents often come from a natural source, and are also a waste product. One of these is chitosan. Chitosan is a derivative from chitin, mainly found in the exoskeleton of crustacean. Some research has been conducted on chitosan and wood. Chitosan has earlier proven good antifungal effectiveness, but to achieve a good protection, a 5 % concentration is needed, which makes the end product quite expensive. In recent research, a way to make chitosan treated wood hydrophobic has been invented. The objective of the research presented in this paper, is to describe the effectiveness of the following compounds: Chitosan, chitosan/copper, chitosan/boron and chitosan/Scanimp (a commercial wood preservative). Results show that chitosan works well alone, but has a fixation problem. Chitosan and boron give good fixation, and reduced amounts of chitosan and together give good protection against wood destroying fungi. The fire protection agents are promising, but needs higher concentration and/or better fixation to give a sufficient protection against wood destroying fungi
Authors
Erik ChristiansenAbstract
Hylobius abietis L. feed on the stem bark of conifer seedlings. In the absence of appropriate control measures, the damage may reach a level that rules out planting as a means of conifer regeneration. It is distributed throughout the coniferous forests of northern Eurasia, including the British Isles and Japan. Other Hylobius species cause damage of a similar type, both within this area, and in North America. Soon after the introduction of clear felling systems in Central Europe, damage by H. abietis became wide-spread.
Authors
Erik ChristiansenAbstract
Among thousands of bark beetle species worldwide, only a handful is able to attack and kill trees on a large scale. One of these is the 8-toothed spruce bark beetle, Ips typographus L., indigenous to the Palaearctic forests and recently introduced into North America. In Europe, the main host is the Norway spruce, Picea abies (Linnaeus) Karsten; in Eastern Asia, including Japan, the main hosts are spruces of the P. jezoensis group. In unmanaged forests, these beetles play an important ecological role by killing old trees and stands, thus promoting biomass recycling and ecosystem rejuvenation. Foresters who are faced with extensive tree mortality do not, however, welcome this activity: managed forests of Europe have lost hundreds of millions of trees in recurring outbreaks
Authors
Peder Gjerdrum Anna BarszczAbstract
The present research concerned selected characteristics of knottiness of large-dimensioned spruce timber (of trees with the minimum breast-height diameter of 40 cm over bark) from three stands, over one hundred years old, located in south-eastern Norway. Fourteen sample trees were felled and measured, and knots which occurred in them were classified into three categories of healthiness and three categories of tightness with the surrounding wood. Sound and tight knots were dominant in the timber under analysis. All categories varied significantly in relation to average diameters, relative diameters (related to stem thickness at the points where the knots occurred) and the relative height of location along merchantable boles. The researches analysed the significance of relations of diameters or relative diameters of knots with the relative height of their location along merchantable boles...
Authors
Nicola La Porta Paolo Capretti Iben Margarethe Thomsen Risto Kasanen Ari M. Hietala Kim von WeissenbergAbstract
Most atmospheric scientists agree that climate changes are going to increase the mean temperature in Europe with increased frequency of climatic extremes, such as drought, floods, and storms. Under such conditions, there is high probability that forests will be subject to increased frequency and intensity of stress due to climatic extremes. Therefore, impacts of climate change on forest health should be carefully evaluated...
Authors
Clemens Reimann Belinda Flem Arnold Arnoldussen Peter Englmaier Tor Erik Finne Friedrich Koller Øystein NordgulenAbstract
Le Roux et al. consider the approach that led to the above article as trend-setting. However, according to Le Roux et al. the data are unfortunately ‘‘inappropriately interpreted”. It is appreciated that le Roux et al. took the effort to study the original data and attempted a re-interpretation along the lines of an impressive list of publications which they claim have been ignored by Reimann et al. (2008). Here the achievements and shortcomings of their alternative interpretation will be discussed in view of the facts substantiating the conclusions of the original article......
Abstract
The inhibitory effect of methanol bark extracts from six deciduous and three coniferous European tree species were bioassayed against eight fungi from the different damage categories, brown rot, white rot, canker and blue-stain. This is the first report providing data on the antifungal activity of several Europaen tree species against fungi within these damage categories. Generally the decay fungi were more inhibited by the bark extracts than the blue-stain fungi, while the lowest inhibition was found among the cancer fungi. The main pattern found between the fungal groups in relation to the bark extracts in this study is believed to be caused by the route of ingress. Acer platanoides bark extract proved to be the most effcient bark extract tested, significantly reducing the growth rate of all tested fungi. Betula pubescens bark extract generally gave the weakest reduction in growth rate. In this study, the conifer bark extracts were in general more active against the canker and blue stain ascomycete fungi than the deciduous trees extracts.