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
Peder GjerdrumSammendrag
Pine (Pinus sylvestris) heartwood and pine sapwood can, in several respects, be considered two different timber products. Sapwood demonstrates open structures that easily adsorb moisture and is vulnerable to bio-chemical disintegration, but also more easily painted, glued or impregnated. Heartwood, on the other hand, is less disposed to moisture fluctuations, hence, more dimensionally stable, and durable. Heartwood content is closely related to cambial age and to the progress of annual ring width. It is also the nature of pine is to grow timber of quite varying quality along the stem. Resins are more abundant near the base, and the knottiness is shifting, following certain patterns from the base upwards. Several of those traits can be identified prior to breakdown, applying specific wood technology knowledge, recent research and standard log scanner equipment. Even with this potential for producing more homogeneous board quality by including heartwood in the breakdown decision basis, one should not forget the practical implications for the sawmill. The cost of keeping separate heartwood quality classes and the risk of mistakes might easily exceed the price gain.
Forfattere
Silja Korhonen-Sande Erlend NybakkSammendrag
Det er ikke registrert sammendrag
Sammendrag
Runoff time series are known to contain long term structures on interannual to decadal time scales. Investigating spatial patterns of long term structures is a way to elucidate the relationship between external forcings and watershed properties. This would be a valuable contribution to an improved water resources management. Singular System Analysis (SSA) is a powerful technique to identify and extract significant long term components from time series. However, many observations from natural systems are prone to missing data that hamper many analysis techniques, including the SSA in its original formulation...
Forfattere
Per Otto FlæteSammendrag
The use of traditional preservative treated wood has been highly restricted in recent years, and there is a need to find environmental benign alternatives. Utilisation of naturally durable wood is commonly proposed as an alternative for wood used in above ground applications. Traditionally, heartwood of Scots pine (Pinus sylvestris L.) has been used in constructions prone to biological degradation. However, when utilising the heartwood for solid wood products, one has to consider that the stemwood of Scots pine also comprises non-durable sapwood, and that the heartwood varies with respect to decay resistance. The purpose of this thesis was to study techniques for improved utilisation of natural durability, with special focus on Scots pine heartwood. A study was conducted aiming to describe the variation of heartwood diameter in mature Scots pine...
Sammendrag
Many time series analysis methods depend on equally spaced observations with no data point missing. If this condition is met, powerful techniques are available that identify temporal structures such as trends or periodic phenomena or nonlinear dynamics. Unfortunately, most of observations of natural systems, in particular over longer periods of time such as decades, are prone to sampling errors leading to missing points in the observations. Singular System Analysis (SSA) is a powerful tool to extract the dynamics contained in time series at arbitrary temporal scales...
Forfattere
Toril Drabløs EldhusetSammendrag
Oxalate exuded constitutively by Picea abies / Laccaria bicolor may lead to rhizosphere oxalate concentrations relevant for Al resistance.
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
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Sammendrag
In this study, the effect of two boric acid concentrations (1% and 2%) and four derivates of tall oil with varying chemical composition were tested separately and in combination. The tall oil derivates were chosen in a way that they consist of different amounts of free fatty, resin acids and neutral compounds. Decay tests using two brown rot fungi (Postia placenta and Coniophora puteana) were performed on both unleached and leached test samples. Boric acid showed a low weight loss in test samples when exposed to fungal decay before leaching, but no effect after leaching...
Sammendrag
Det er ikke registrert sammendrag