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.
2011
Authors
Bernt-Håvard ØyenAbstract
Sitka spruce (Picea sitchensis (Bong.) Carr) is native to the Pacific North West of America and was introduced to Western Europe in the early 19th century. It is now an important commercial species along the extreme western seaboard of Europe – namely Ireland and Great Britain – and this is where most progress has been made in the area of selection and breeding. Sitka spruce has been the subject of more limited selection and breeding work in some other European countries where it is of secondary or minor significance - Denmark, France, Germany, and Norway. These programmes have now effectively come to a close due to perceived lack of importance. In Sweden Sitka spruce is being planted at an increasing rate and is seen as a species of great potential in the light of climate change. This monograph presents details and statistics relating to Sitka spruce breeding across Europe. It summarises the work carried out to date (plus trees, field testing, orchards), the gains achieved, knowledge of genetic relationships between selection traits, and acts as a conduit to further references for the interested reader.
Authors
Merete Wiken Dees Arild Sletten Ricardo Holgado Eldrid Lein Molteberg Tor J. Johansen May Bente Brurberg Vinh Hong Le Ragnhild Nærstad Arne HermansenAbstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
The Norwegian National Forest Inventory (NNFI) provides estimates of forest parameters on national and regional scales by means of a systematic network of permanent sample plots. One of the biggest challenges for the NNFI is the interest in forest attribute information for small subpopulations such as municipalities or protected areas. Frequently, too few sampled observations are available for those small areas to allow an estimate with acceptable precision. However, if an auxiliary variable exists that is correlated with the variable of interest, small area estimation (SAE) techniques may provide means to improve the precision of estimates.
Authors
Arnstein ØvrumAbstract
No abstract has been registered
Authors
Peder GjerdrumAbstract
Scaling accuracy is of utmost importance to obtain optimal yield in log breakdown. In this paper we have combined sawmill experience, a review of available publications and supplementary observations to analyse the accuracy of roundwood scaling for Norway spruce and Scots pine. The influence of ovality, bark thickness variation and bark damage were analysed for scaling in one-directional and two- directional shadow scanners, and for three-dimensional (3D) reflected beam scanners. The overall accuracy for diameter under bark can be calculated by adding the variances for each independent term. For unbarked logs, shadow scanners with two perpendicular directions are most accurate. Results show that 3D scanners are most accurate, provided used for barked logs. For a case study, transferring from scaling unbarked logs in a two-dimensional shadow scanner to a full 3D scan of barked logs reduced annual roundwood consumption by 2.0%.
Abstract
No abstract has been registered
Authors
Arnold ArnoldussenAbstract
Publiced earlier in English in 2006. In 2011 revised and translated into Chinese.
Abstract
No abstract has been registered