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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.

2011

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Abstract

The use of logging residues for bioenergy is encouraged in many countries, due to an increasing demand for renewable energy. However, there is concern that removal of logging residues may cause a long-term reduction in soil nutrient availability, reducing forest growth in the remaining stand. To quantify the growth response of Norway spruce and Scots pine to whole-three harvesting at first thinning a series of eight field experiments was set up in SE Norway in the seventies. Results after 25 years showed that whole-tree thinning lead to a decrease in forest growth. The effect was present more or less immediately after thinning, and was still present after 25 years. The average reduction in growth was around 10 % after 25 years in the spruce stands, while in the pine stands a non-significant average growth reduction of 4 % was found. The results are generated under experimental conditions, and in practice a share of the residues is left on site, decreasing the nutrient loss.

Abstract

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.

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.