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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.

2023

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Sammendrag

Key message This study compares the measured radial variation in wood stiffness, strength, and density of noble fir, Norway spruce, western hemlock, and western red cedar by developing mixed-effects models for each property using age as the explanatory variable. These models could be used to simulate the effect of rotation length and species choice on sawn wood properties. Context Timber production in Great Britain relies primarily on Sitka spruce. The use of multiple species is desirable to mitigate against biotic and abiotic risks posed to a single species. When considering alternative species, quantifying and modeling radial variation in wood properties is important to determine the potential for sawn timber production at a given rotation length. Aims To build empirical models for the radial variation in wood properties that can account for species. Methods Clear-wood samples were produced along radial transects in trees from four conifer species: Abies procera Rehder, Picea abies (L.) Karst, Tsuga heterophylla (Raf.) Sarg., Thuja plicata Donn. ex D.Don. Modulus of Elasticity, Modulus of Rupture, and density were measured on each species according to established standards. Mixed-effects models were built using ring numbers from the pith and species as explanatory variables. Results The same model forms could be used across the four species. Nonlinear models were developed for the Modulus of Elasticity and density. For the Modulus of Rupture, a linear model was most appropriate. The effect of species in the models was significant. Conclusion At similar rotation lengths, noble fir, Norway spruce, and western hemlock can produce timber with comparable properties to Sitka spruce. Overall, western red cedar would have worse properties for structural use. Keywords MOE, MOR, Radial variation, Tree growth, Alternative species

Sammendrag

An expert workshop on C and N interactions was held online 6 – 7/11 2023, within project Kvävebegränsningar för kolbindning i skandinaviska skogar/Nitrogen constraints to carbon sequestration in Scandinavian forests, financed by the Nordic Working Group for Climate and Air (NKL). The workshop was organized in two half-day sessions. Sweden, Finland, Norway and Denmark were represented by experts involved in national reporting to the UNECE Air Convention (CLRTAP) and to the UN Climate convention (UNFCCC). This workshop report was prepared by the workshop organizers at IVL Swedish Environmental Research Institute, with contributions from all workshop participants.