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
Anna Martha Elgersma Shivcharn S. Dhillion Arnold Arnoldussen Josef Fanta Eva BoucníkováSammendrag
Det er ikke registrert sammendrag
Forfattere
S. Craig DeLong Glenn D. Sutherland Lori D. Daniels Ben H. Heemskerk Ken Olaf StoraunetSammendrag
Patterns of tree mortality, rates and type of tree and snag fall, and relationships between snag characteristics and potential wildlife habitat value were estimated for hybrid spruce (Picea glauca (Moench) Voss x engelmannii Parry ex Engelm.) and subalpine fir (Abies lasiocarpa (Hook.) Nutt.) in eastcentral British Columbia in order to provide important parameters for deadwood modelling. We sampled 172 snags (52 spruce and 120 fir) for species, size, morphological, and habitat attributes, and used dendroecological techniques on a subsample of these (n = 158) to estimate year of death. Input of snags appeared to occur at a nearly constant rate in these stands. Estimated annual tree fall, including live trees and snags, was 5.3% for hybrid spruce and 6.1% for subalpine fir and stem breakage was more frequent than uprooting. Long-term annual snag fall rates were 4.6% for hybrid spruce and 2.9% for subalpine fir. Discriminant analysis based on time since death correctly classified snags into three decay classes for 85% and 72% of spruce and fir, respectively. Snags that potentially could provide important functions for wildlife habitat were more prevalent in fresh and intermediate classes for hybrid spruce and in intermediate and old classes for subalpine fir. The results provide valuable parameters for further development of deadwood models, which are an important tool for development of best practices for deadwood management.
Forfattere
Daniel Kwaku A. Asante Anne-Katrine Ree Rosnes Anna Holefors Ragnhild Nestestog Stein E. Lid Jørgen A. Mølmann Jorunn Elisabeth Olsen Øystein Johnsen Olavi Junttila Carl Gunnar FossdalSammendrag
Studies have implicated the involvement of the phytochrome light receptors in adaptation of trees to light climate, but the molecular basis of this in gymnosperms is less understood. The promoter regions of plant genes are modular and contain a number of cis-acting elements, each of which may contribute to one or more aspects of a complex expression profile. As a step towards characterization of Norway spruce phytochromes at the transcript level, we isolated fragments (between 700-1500 bp upstream of their putative ATG translational start) of phytochrome N, O and P promoters...
Forfattere
Daniel Kwaku A. Asante Igor A. Yakovlev Carl Gunnar Fossdal Anna Holefors Lars Opseth Jorunn Elisabeth Olsen Olavi Junttila Øystein JohnsenSammendrag
Short days (SD) trigger cessation of elongation growth and transition from an actively growing apex to a terminal bud in woody plants of the temperate and boreal zones. The molecular basis behind this is not well understood in gymnosperm forest trees such as Norway spruce. By combining suppression subtractive hybridization (SSH) libraries and monitoring of gene expression using quantitative RT-PCR analysis, we aimed to identify genes involved in photoperiodic control of growth cessation and dormancy induction in Norway spruce. The gene expression patterns described here will be useful for future detailed functionalanalyses.
Forfattere
Jørund Aasetre Vegard GundersenSammendrag
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...
Forfattere
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 SperisenSammendrag
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...
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
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
Forfattere
Erik ChristiansenSammendrag
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.
Forfattere
Erik ChristiansenSammendrag
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